This Landsat 8 image from May 24, 2017, shows an enthralling New Zealand landscape. Tongariro National Park surrounds snow-capped Mount Ruapehu on the right, and the boundary of forested Egmont National Park forms a nearly perfect circle on the left. Mount Taranaki marks the center of the park, which is surrounded by green farmland. The white running through the middle of the scene is fog accompanying the Whanganui River.

The scene was downloaded on March 9, 2020, one of over 29,000 Landsat scenes downloaded worldwide that day.

But this scene is special.

The picturesque view of New Zealand’s North Island marks the 100 millionth downloaded from the archive at the USGS Earth Resources Observation and Science (EROS) Center since Landsat data became freely available on October 1, 2008.

That’s one scene every 3.6 seconds since the open policy began. Ok, we know some of you download gobs of data all at once—that’s just an average.

And it’s a number that wouldn’t be possible if the data weren’t free and open.

These downloads help researchers conduct countless land change studies and provide essential information to help land managers and policy makers make wise decisions about our resources and our environment.

Landsat 7, launched in 1999, and Landsat 8, launched in 2013, together acquire over 1,200 images each day. With the launch of Landsat 9 on the horizon, the amount of acquired data will increase to about 1,500 images each day.

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Landsat 7, which launched on April 15, 1999, has been continuing to acquire land images worldwide for 16 years. Landsat 5 may hold the Guinness World Record for longest Earth-observing satellite at 28+ years, but Landsat 7 also has an impressive track record. In fact, Landsat 7 has now acquired over 2 million images. They are all freely available online at USGS GloVis or EarthExplorer.

Landsat 7 and Landsat 8 acquire over 1,200 new images per day. This is more data than at any other time in the history of the Landsat program.

The 2 millionth Landsat 7 scene includes a portion of northwestern Madagascar, acquired on September 11, 2015. The dark region in the lower left is the Ankarafantsika Nature Reserve. This large area of deciduous forest, savannah, and wetland is protected as a national park. On the left edge of the scene is Mahajamba Bay. This shallow bay contains Madagascar’s largest mangrove ecosystem, with tidal mudflats along the edges of the mangroves.

On December 26, 2004, a massive 9.1 magnitude earthquake struck off the west coast of northern Sumatra, Indonesia.

The third largest earthquake ever recorded lifted the sea floor several meters, causing tsunami waves to ripple out in all directions and race across the ocean.

Banda Aceh bore the brunt of the waves just 15 to 20 minutes after the earthquake. Waves in some locations along the Sumatra coast were reported to be 30 meters high.

Images from Landsat 5 show the coastline before and after the tsunami struck, revealing where vegetation was stripped from the land.

Landsat provides rapid assessments of damage to land resources after natural disasters such as tsunamis, and continues to monitor recovery years later.

Scientists observed rifts in Petermann Glacier throughout the first decade of the 2000s. The rift that caused the 2010 break was first spotted in satellite imagery in 2001. See below for the location of this rift in a 2001 Landsat image.

The massive calving event in 2010 removed 28 kilometers of the ice shelf. The result was an ice island four times the size of Manhattan, about 270 square kilometers. It was the largest iceberg to form in the Arctic since 1962.

The last image displayed in this section shows a size comparison of Manhattan Island (yellow outline) to the iceberg.

(Black stripes run through the images because of the Scan Line Corrector failure on Landsat 7 in May 2003.)

Just two years later, another large iceberg broke off Petermann Glacier. This one was estimated at 130 square kilometers—about half the size of the 2010 iceberg. But this calving broke off the glacier tongue farther upstream and moved the front end of the glacier farther inland than has been observed since 1876, the first reported measurements of the glacier.

The floating ends of glaciers like Petermann are known as ice shelves. They act as doorstops. When these ice shelves suddenly splinter and weaken, the glaciers that feed them speed up. The result is more ice flowing into the ocean, which could raise global sea levels.

The development of these icebergs is a natural process; however, when there are two major breaks in two years, scientists must take notice. Even large breaks do not amount to a collapse of the floating extension; nevertheless, they are important events.

(Black stripes run through the images because of the Scan Line Corrector failure on Landsat 7 in May 2003.)

The 2014 Fédération Internationale de Football Association (FIFA) World  Cup began on June 12, 2014, and has been taking place at numerous venues across Brazil. The final match is on Sunday, July 13, at the Maracanã Stadium in Rio de Janeiro.

This Landsat 7 image was acquired on June 26, 2014. The main image  shows the spectacular setting of the city of Rio, with its high mountains, islands, and famous long beaches that follow the coastline. The smaller image shows the location of the stadium (white circle) where the 2014 World Cup final match will take place. 

These “pan-sharpened” images use Landsat’s panchromatic band (15-m resolution) in combination with the 3-band multispectral information (30-meter resolution). This technique is often used by scientists and  analysts when it is necessary to show more details within the Landsat image than would be visible using the multispectral information alone.  

 

A magnitude 7.8 earthquake struck Nepal on April 25, 2015. Along with damage due to shaking, the earthquake and its aftershocks triggered many large and small landslides throughout the region. As of early May, over 3,000 individual landslides had been identified, based on analysis of hundreds of satellite images collected after the earthquake.

The background image above is a Landsat 8 mosaic of the entire region, produced by stitching together Landsat images acquired from 2013–2014.

The insets show an image pair acquired by WorldView-2 and WorldView-3 over one example location near the town of Namrung, Nepal. Comparing the image acquired shortly after the earthquake with an image from a previous date allows scientists to map the exact locations and extent of local changes caused by the landslides. Here, the post-event (May 8) WorldView-2 image shows one major landslide, as well as many smaller-scale slides that also occurred along the river valley after the earthquake. The image also shows a new lake that formed behind the largest landslide, as a result of damming of the Tom Khola River.

This inset image pair shows just one location, and these changes have occurred across the landscape, especially in the mountainous regions.  

Scientists will continue to monitor the region with various satellite data. As post-event images become available, earthquake damage and landslide maps are being created and updated. For more information (including earthquake damage assessments and a landslide inventory map) see the International Charter ‘Space and Major Disasters’ home page: https://www.disasterscharter.org.  

 

A new rift formed on Petermann Glacier in 2017. An older crack to the right of the new rift also extends toward the glacier’s center. By 2020, this new rift had met up with the older crack. If an iceberg breaks off, it would be Petermann’s third massive iceberg calving since 2010. It also could place the new calving face much farther upstream than the 2010 break.

Close-up images from Sentinel-2 take advantage of its 10-meter spatial resolution to show the new rift in greater detail. Landsat 8 and Sentinel-2 complement each other by imaging glacial movement and possible calving events.

The prominent vertical line could be from deformation of the ice as it flows over the bedrock farther upstream. The irregular topographic surface of the underlying bedrock could have caused the ice to develop this longitudinal crevasse as it moved over bedrock, resulting in a line being drawn the length of the glacier as it flows. Besides the new rift, other bumps and lines extend from this longitudinal line, which are stress fractures from the glacial movement.

Along with becoming longer, notice that the rifts are also moving downstream between 2017 and 2022 as the glacier flows.

On April 30, 2018, rapid changes in the East Rift Zone were detected. The Pu‘u ‘Ō‘ō crater floor collapsed. Ground deformation toward the east indicated magma intrusion approaching the Leilani Estates neighborhood, 20 km from Pu‘u ‘Ō‘ō.

Based on numerous geological, geochemical, and geophysical instruments, the USGS Hawaiian Volcano Observatory and other scientists determined that magma had drained from below Pu‘u ‘Ō‘ō crater. It then intruded through underground tunnels and emerged at eruptive vents, or fissures, in the lower East Rift Zone.

On May 3, the first of 24 fissures along a 6-km line opened within Leilani Estates. Fissure 8 became the dominant vent on May 28. It shot lava tens of meters into the air and sent a vigorous flow toward the coast, ultimately entering the ocean near the eastern tip of the island.

This series of images shows the progression of the lava flows throughout the summer of 2018. Clouds often obscure views of the island, but numerous observations from Landsat, Sentinel-2, and Resourcesat offered peeks through the clouds to the location of fresh lava. Some of the images also show “laze.” When lava mixes with seawater, it creates a noxious gas plume that looks like clouds or smoke. The word is a blend of the words lava and haze. Laze can cause skin and eye irritation and breathing difficulties.

This flow ended abruptly on August 4, 2018. By this time, lava had destroyed more than 700 structures, covered 13.7 square miles (35.5 km²) of land, and added about 741 acres (300 hectares) of land to the island. Lava was a couple hundred meters thick in some places.

A wet 2018–2019 winter caused extra plant growth on Maui, and thus extra fuel, and was followed by drought and record-breaking heat in summer 2019. That set up conditions for an intense fire season. Firefighters reported the unusual weather conditions that made the fires worse: above normal temperatures and below normal humidity.

In summer 2019, at least 19,300 acres burned across Maui, nearly all of it in the former cane fields. The dry grasses that largely replaced the cane fields are especially vulnerable to fire. Notice that the fire scar visible in the July 27, 2019, image didn’t last long, evidence that, unlike a forest fire burn scar, nonnative grass recovers rapidly and outcompetes native grasses after a fire.

These images show a portion of the Texas Panhandle where it meets the western border of Oklahoma. The area is part  of the “Granite Wash” region, which contains over 3,600 wells that mine oil and natural gas from as deep as 17,000 feet  (5,182 meters) underground.



When comparing Landsat imagery from 1986 (left) and 2014 (right), many changes can be seen on the landscape. The large number of white spots in the second image indicates an overall increase in the number of oil wells. The reduced overall greenness (vegetation) in the second image was caused by several recent years of drought. Other visible changes include additional center-pivot irrigation systems (dark circles). There are also several new burn scars from wildfires that occurred  in March 2014.



As the Landsat archive grows, its imagery can be used to record and monitor many different types of landscape changes through time.

The shoreline area of Incheon, South Korea, has been changing dramatically over the past 32 years, as depicted by these Landsat images acquired in 1981 and again in 2013. Previous marsh areas have been turned into usable land through land reclamation. Urban growth has also expanded.



In the center of these images, previously separate islands have been joined together as reclaimed land to become home to Incheon International Airport. The airport opened in 2001 and is now one of the largest and busiest in the world. The new Incheon Bridge (also called the Incheon Grand Bridge) can also be seen in the second image; it opened in October 2009.  



The Landsat archive contains 40 years of data, which allows users to see changes as they are occurring throughout the Earth’s landscape.

The violent eruption of Mount St. Helens 35 years ago permanently changed the mountain and surrounding forest. The volcanic blast on May 18, 1980, devastated more than 150 square miles of forest within a few minutes. In these Landsat false-color images, forest appears as bright red interspersed with patches of logging. Snow appears white, and ash is gray.

Before the eruption, Mount St. Helens towered about a mile above its base, but when the volcano erupted, its top slid away in an avalanche of rock and debris. When measured on July 1, 1980, the mountain’s height had been reduced from 9,677 feet to 8,364 feet—a difference of about 1,300 feet.

The 2014 Landsat image shows vegetation regrowth, as light red and pink, in the devastated area. However, the gray around the mountain is still evident, and the volcanic crater is still prominent as an “amphitheater,” where the peak of the mountain slid away.

Scientists are using this opportunity to witness the recovery process, both with satellites and on the ground. With its 40-plus years of consistent imagery, the Landsat archive is perfect for studying the landscape changes caused by natural disasters and the gradual recovery process.

The Landsat archive, the world’s longest continuously acquired collection of space-based, moderate-resolution land remote sensing data, has now surpassed 7 million scenes since Landsat 1 first began collecting data in July 1972. This Landsat 8 image acquired on June 27, 2017, represents one of those millions of scenes to be added to the archive.

Across the lower portion of this image in northeastern Alaska, clouds cover the Franklin Mountains area of the Brooks Range. Several rivers flow north from the mountains into the Beaufort Sea. The Canning River marks the western border of the Arctic National Wildlife Refuge, a largely primitive and undisturbed region.

The prominent mountain range in the center of the image running east to west is the Sadlerochit Mountains. North of the mountains, the land becomes a flat-to-hilly treeless area called the North Slope coastal plain tundra. Off the coast, sea ice floats on the Beaufort Sea, and dark represents open water in this summer scene.

Northern Alaska receives sunlight 24 hours a day this time of year. Landsat normally acquires imagery only during the day on the descending part of its polar orbit, when the surface of the Earth is in sunlight. But at these high latitudes, Landsat 8 takes the opportunity during summer to acquire imagery during the ascending “nighttime” part of its orbit.

The day-lit ascending campaigns in high latitude regions increase the Landsat coverage in these persistently cloudy areas. The sun angle is different from a typical Landsat scene, providing a twilight glow to the scene.

The 7+ million Landsat scenes are available for download at no charge from EarthExplorer, GloVis, and the LandsatLook Viewer. Follow the Landsat Program on Twitter @USGSLandsat or Facebook @NASA.Landsat.

The Landsat archive has added its 8 millionth scene.

This stunning image was captured by Landsat 8 on July 28, 2018. It shows the coastline of Nordaustlandet, the second-largest island in Norway’s Svalbard archipelago.

Most of the island is covered by massive white ice caps. The exposed rocky coast appears in reddish brown, peppered with blue and black lakes and flecks of white.

The tiny island of Storøya is visible to the east. More than half of Storøya is also covered in ice.

More than 1,100 Landsat scenes are added every day to the archive at the USGS Earth Resources Observation and Science (EROS) Center in Sioux Falls, South Dakota.

The archive added its 7 millionth Landsat scene just over one year ago, in June 2017. The image of northeastern Alaska shows part of the Brooks Range, the western border of the Arctic National Wildlife Refuge, and a treeless coastal plain.

Both Landsat images are part of the Earth’s longest continuously-acquired collection of space-based, moderate-resolution land remote sensing data. The first Landsat scenes were collected in 1972.

Landsat data are available for download at no charge from EarthExplorer, GloVis, and the LandsatLook viewer.

The high-water marks set by the Big Sioux River in cities across southeastern South Dakota have threatened to overtake records set 50 years ago, when the Army Corps of Engineers led missions to document the damage through hundreds of aerial photographs.

This shot from April 10, 1969 shows black flood waters stretching north and south of just one of those cities: Dell Rapids, South Dakota. The Big Sioux had topped 16.47 feet the day before – a foot and a half higher than major flood stage.

The river reached nearly 16 feet in March of 2019. This natural color Landsat 8 image was captured a day before the crest, and shows floodwaters fanning out in patterns remarkably similar to those observed 50 years before.

The flooding footprint was still clear two months later, as plots of green vegetation begin to emerge.

Taking a closer look at Garden City shows the expansion in area the city experienced since 1972. They also show the proximity of the city to those center-pivot irrigation circles. Four of these circles take up almost 1 square mile, or one section, of land.

Southwest of Garden City is an area absent of irrigated crops. This marks the location of the Sandsage Bison Range Wildlife Area, a reserve for many Plains natives, including an American bison herd.

Another gap in irrigated cropland is a bit to the west of the game refuge. Marked by light spots is Holcomb Station, a coal-fired power plant operated by the Sunflower Electric Power Corporation. The plant opened in 1983, so it does not appear in the 1972 Landsat image. The 362-megawatt station uses coal mined in Wyoming's Powder River Basin.

The coastal wetlands of Senegal are centered on the Saloum River and a myriad of estuaries and tidal flats that make up this complex ecosystem. The estuaries are generally bordered by dense, vigorous stands of mangroves (dark red tones in the Landsat images). Part of this ecosystem is protected in Saloum Delta National Park. The wetlands are critical habitats for wintering Palearctic birds, as well as many species of fish and mollusks.

The mangrove vegetation is made up of several species. Some mangrove species form low canopies, but others of the Rhizophora genus are among the tallest in the world, attaining heights of up to 40 meters. Mangroves grow in habitats that are periodically flooded by seawater (tidal influence) and river water. They are halophytes, plants that grow in salty environments.

Since the late 1960s, it has become apparent that many of the mangrove forests are dying. One theory is that there is a serious mangrove disease that is systematically wiping them out. However, most evidence indicates that the mangrove die-off is related to the widespread Sahelian drought, which has plagued the region since 1968. The lack of rainfall has led to an accumulation of salts, exceeding the tolerance levels of the mangroves.

The die-off is particularly acute in the northern half of the Saloum River wetland complex (note the change in tone on the Landsat imagery, from dark red to dark gray). Today, there are vast areas of standing dead mangrove carcasses; many of these areas have been reduced to barren mud flats. The southern reaches of the wetland complex, however, still has healthy stands of mangrove forests.

New fissures opened up on Hawaii’s Big Island in early May 2018, spouting lava that destroyed homes in the Leilani Estates neighborhood. The new activity from the Pu’u ‘O’o Crater of the Kilauea volcano is a reminder that the volcano has been very active in recent decades.

Landsat has been recording the lava flows on the Big Island since the latest eruption began in 1983. The most current image shown is from India’s Resourcesat-2 satellite, which spotted the lava flow in Leilani Estates despite the cloud cover.

In these images, green vegetated land is repeatedly covered with dark lava flows, and infrared imaging shows bright orange spots where there is the most heat.

Eruptions from the Pu’u ‘O’o Crater have a history of burying towns. The 1991 image shows a new lava flow extending toward the east along the coastline. This lava flow buried the entire community of Kalapana in 15–25 meters of lava in 1990. The narrower flow that extends to the northeast occurred between 2014 and 2016, and approached the community of Pahoa.

The image series also shows how the coastline of the island has changed as various lava flows reached the ocean. Landsat and other Earth-observing satellites continue to monitor the rapidly changing landscape of the island.

The Cheyenne Bottoms are on the North American Central Flyway, kind of a bird highway for migration. The vast, diverse marsh provides food and water for a multitude of migrating bird species during both spring and fall migrations. Most of Kansas is too dry for such a stopover, and reservoirs are too deep. Birds need shallow water and long shorelines.

Summer 2022 had below normal precipitation statewide and above normal temperatures. No water was available from Wet Walnut Creek to divert into the Bottoms. By November 2022, the U.S. Drought Monitor showed that a third of Kansas was in exceptional drought. Landsat images from October 2021 and October 2022 show that birds had nothing to stop for in fall 2022.

This summer in central India, a mystery in color emerged.

In the space of just days, the surface of Lonar Lake turned bright pink, then returned to green.

As scientists study the cause of the event, other lakes around the world offer clues.

Australia's salty Lake Hillier is filled with microscopic pink organisms, as well as algae that turn red when stressed to help absorb light. The same type of algae is prevalent in Senegal's Lake Retba, where red hues are clearest during the dry season. Lake Urmia in Iran turns red when water levels drop and salinity spikes. Similar salinity fluctuations have been observed in Lonar Lake.

Maybe the lake will blush again, or maybe this was a one time event. Satellites like Landsat and Europe's Copernicus Sentinel-2 will be watching.

Throughout 2016, Indiana has been celebrating its 200th anniversary of statehood. Joining the Union on December 11, 1816, as the 19th state, Indiana was the second state admitted from what was once known as the Northwest Territory.

This satellite mosaic of the Hoosier State was created from several Landsat scenes stitched together to create one seamless image. Data from the National Elevation Dataset (NED) is also incorporated into the image. The names of major cities and county boundaries have been added.

The Landsat images used for this mosaic were from summer months, so it shows the state at the height of the growing season. Since farmland makes up about 70% of the state’s land, much of the state appears green. By contrast, urban areas appear in shades of lavender. The large spot in the middle of the state marks the location of Indiana’s capital and largest city, Indianapolis.

The Wabash River, the official state river, flows west across the northern part of the state and turns south to form part of the border with Illinois.

Poster-sized images of all 50 states, plus Puerto Rico, are available for download at no charge at http://eros.usgs.gov/imagegallery/landsat-state-mosaics.

Floods are examples of short-term environmental change. They cause substantial damage and change for only a short time, such as a couple of weeks. The damage done to crops can last for an entire growing season, but in most cases, the landscape goes back to normal after the floodwaters recede. In some cases, however, a flood can cause more lasting change.

This flood changed the course of the Wabash River just above where it flows into the Ohio River. We have to go to a different Landsat image to see this happen, the one just south of the scene we’ve been examining. Images show a new cutoff that was formed from this flooding. About 2,200 acres of the land was rendered inaccessible by the new cutoff and shortened the river by about 7.5 miles.

An iceberg the size of Houston broke from the Brunt Ice Shelf Antarctica on January 22nd, 2023. Landsat images show the area one day before the break and several days after. A feature named Chasm 1 had been lengthening for years, and it finally reached all the way across the shelf. Landsat will continue to track the new iceberg, named A-81, as it floats into the Weddell Sea.

More than 10,000 thermal features pepper the landscape of Yellowstone National Park.

Most of the hot springs, geothermal vents, and geysers are clustered around 120 distinct thermal areas. Scientists with the USGS Yellowstone Volcano Observatory use satellite and aerial imagery to map them as they expand and contract.

They recently found an entirely new thermal area.

It emerged quietly over 20 years, miles from the nearest trailhead but close to an existing hot zone.

Landsat 8's thermal infrared sensors captured the change in a nighttime image from April of 2017. Heat signatures are clearest at night, when unheated ground is cool.

Aerial images told more of the story. Forest covered the area in 1994, but the emergent thermal zone had begun to fry trees by 2006. Before long, the hot spot was unmistakable, with felled trees piled like toothpicks in a patch of land roughly the shape of a thumbprint.

Scientists rely on both satellite and high-resolution airborne imagery archived with the Earth Resources Observation and Science (EROS) Center to monitor Yellowstone.

The Landsat images that are shown on Earthshots are combinations of three different wavelengths of the electromagnetic spectrum. Typically, the images show a combination of visible and infrared light; therefore, they are false color images. When these wavelengths, or bands, are shown individually instead of combined, different details sometimes emerge.

In the case of this Selkirk Karman vortex street scene, Landsat 7’s band 5 hints at a feature not visible in the image featured in the first section, which is a combination of bands 5, 4, and 3. Do you see it? Band 7 shows it even better. Northeast of the island, just east of the vortices, there is a bright spot and a bright plume trailing from it to the northeast. This may be a westbound ship, the effect of the ship’s exhaust shown in the clouds.

Algal blooms occur annually on Milford Lake in the summer and can be harmful to fragile wetland ecosystems. The USGS Kansas Water Science Center uses multispectral sensors on board drones to identify harmful algal blooms and study how they affect local businesses and human and animal health.

The deep purple in the lower right spreads out into a few channels before fading into a multitude of colors. These channels are remnants of an ancient drainage network in Kenya. The beauty of the colors actually hides a stark reality for hundreds of thousands of people. The dark spots at the top center of the image are refugee camps.

A series of powerful earthquakes tore and shifted the sandy Earth of California’s Mojave Desert in early July.

A magnitude 6.4 earthquake struck near Ridgecrest, California, on July 4, followed a day later by a 7.1-magnitude quake to the north.

The second event created a surface rupture 30 miles long that cut through Naval Air Weapons Station China Lake, a 1-million-acre military installation.

Sentinel-2B images show not only the rupture, but movement of the land itself. The ground west of the epicenter moves slightly northwest as the eastern side moves in the opposite direction. The pattern aligns with a radar analysis from NASA’s Jet Propulsion Laboratory estimating that each side of the fault had shifted two feet or more from its original position. a shift of two feet or more on either side of the fault line.

Government and commercial satellite data will be used by the USGS and other agencies as they work to fully assess the impact of the California earthquake sequence.

Like many lakes in northern Minnesota, Mille Lacs near Brainerd experienced an uncommonly warm winter this year, with lower than average snowfall.

Mille Lacs is Minnesota’s second largest lake, and a popular tourism destination year-round.

Typically in February, the lake is covered with plowed roads used by ice anglers and other adventurers. This year, winter activities were slow to start. The official "ice in" date was much later, and the "ice out" date much earlier.

Natural color Landsat images from the past ten Februarys are shown here, revealing the stark change in 2024.

February's average temperature of 28 degrees Fahrenheit was the highest of the past 10 years.

Landsat's 50 year archive is just one of many important resources used by scientists around the world to study snow and ice trends like these.

In southern Germany, autumn is synonymous with beer.

Around six million people visit the Bavarian city of Munich each year for Oktoberfest, a celebration of suds that coincides with the hops harvest.

The world’s largest continuous hops-growing region by area is Hallertau, just north of Munich. More than 80 percent of Germany’s hops come from this 42,000-acre stretch of fertile loess soil.

The fields of Hallertau appear in green and brown between deep green patches of forest in this Landsat 8 image from August of 2017.

Hallertau might be the largest hops-growing region, but the largest producer is 5,200 miles away. The Yakima River Valley grows around 77 percent of the hops in the United States, which harvests more than any country in the world.

Fields of green fan out along the Yakima River in this Landsat 8 image from July of 2018. The river provides irrigation for the semiarid region, which is also known for it’s vineyards and apple orchards.

It soon became too dark to see A-74, which covered 1,270 km², as the Antarctic winter set in. But Landsat 8 continued imaging with its Thermal Infrared Sensor (TIRS). The imagery is visibly dark, but TIRS detects temperature on the surface.

TIRS shows relatively cooler temperatures darker than warmer temperatures, so the iceberg and ice shelf appear black. Clouds are relatively warmer than ice, so clouds sometimes cover the ice with swaths of gray.

TIRS reveals what could not be seen in the darkness. The iceberg separates from the ice shelf, moves away, then bumps back into it before drifting south. In August 2021, in a timeframe of less than 2 weeks, the berg spun around the tip of Brunt Ice Shelf, brushed past it, rotated counterclockwise, and continued south. Landsat 8 spotted it with its visible bands in February 2022 much farther south along the Antarctic coast.

It’s unknown exactly how the ice shelf will respond to the 2021 North Rift calving. The situation is being monitored closely by Landsat along with Sentinel, WorldView, ground-penetrating radar, drone imagery, and a network of GPS stations.

Near the common borders of Ukraine, Belarus, and Russia, the Chernobyl Nuclear Power Plant lies near the Pripyat River at the northwestern end of a cooling pond. The pond is 12 km long; during normal operation the plant discharged warm water counterclockwise around the pond, taking in cool water near the north end. Just northwest of the plant is the city of Pripyat. The smaller town of Chernobyl lies south of the cooling pond.

The 1986 and 1992 images clearly show farm abandonment. Agriculture appears as a collage of bright green (growing crops) and tan (highly reflective bare ground). Many of these areas appear a flat gray-green in 1992, indicating natural vegetation that has taken over the abandoned fields. The 2011 and 2018 images show that this land change persists.

While the reactor was still on fire, all settlements within 30 km were evacuated, including Pripyat (1986 population 45,000), Chernobyl (1986 population 12,000), and 94 other villages (estimated total population 40,000). This area remains almost completely abandoned and is called the Chernobyl exclusion zone. The area is a mixture of former agriculture, forest, and marshland. It has been mostly free from human intervention since 1986.

Radiation contamination later forced abandonment even outside the 30-km zone. High levels of cesium-137 detected years later caused further abandonment. In all, more than 120,000 people from 213 villages and cities were relocated outside contaminated areas.

In 2011, the director of the Chernobyl power plant, Ihor Gramotkin, was asked when the area would again be inhabitable. He responded, “At least 20,000 years” (Harrell and Marson).

All of the water that keeps the Mesopotamian Marshes alive comes from the Tigris and Euphrates rivers. Those rivers originate from precipitation in the Anatolian highlands of Turkey and the Zagros highlands of Iran, which occurs mostly in winter as snow. The snowmelt then provides—historically, at least—a flooding pulse downstream every spring. The land flattens out in southern Iraq, where the rivers slow and drop sediment, meander, and split into branches before flowing into the Persian Gulf.

The Mesopotamian marshlands absorb the excess water and expand in the spring, then shrink in the summer. That’s the normal seasonal pattern.

In the 1960s, the estimated spring extent of the marshes was 15,000–20,000 square kilometers. The vast marshland is vulnerable to drought and international conflict.

Clouds can be a real headache when it comes to satellite imaging. Thin, almost transparent cirrus clouds are often difficult to spot, leaving scientists scratching their heads when data from pixels beneath them come out slightly skewed.



But Landsat 8 has an answer for that.



The newest spacecraft in the Landsat family – which has been acquiring data since February 2013 – contains a spectral band on its Operational Land Imager (OLI) that identifies the high-altitude clouds that are not otherwise apparent in other bands.



These images show that well. On the left, cirrus formations drift above the landscape. On the other hand, cirrus clouds are difficult to discern in the natural-color composite Landsat 8 image on the right, looking down on Columbia, S.C., and across the border north to Charlotte, N.C.



Scientists are using the cirrus band to flag images that are heavy with cirrus cloud contamination. Landsat’s newest band makes that easy to detect, thus allowing for the most accurate data possible.

 

The home of the Landsat satellite archive is surrounded by corn and soybean fields. The archive is kept at the USGS Earth Resources Observation and Science Center (EROS) located near Sioux Falls, South Dakota. EROS is celebrating its 50th anniversary this year.

The vast archive at EROS also includes aerial photography. A 1958 image shows the farmland before EROS was built. A 1976 photo shot during a flyover shows the center, entrance and exit roads, and a parking lot. A water tower and wastewater ponds supported the large amount of photo and film processing needed for the earliest remotely sensed imagery.

A 1979 photo captured the clearing of land north of the building for the installation of a solar panel array, which heated water for photo processing. The project was completed the following year.

In 1990, a second antenna was added in front of the building. It still functions today as backup reception for NOAA's weather satellites. The first antenna was Domsat, which received Landsat data directly from Goddard Space Flight Center.

1994 reveals the start of construction on the building addition, which was completed in 1996. The Domsat antenna has been removed.

The next year, a 10-meter antenna was placed east of the building for reception of data from the upcoming Landsat 7. This photo, however, was taken shortly after baseball-sized hail damaged it. That storm also destroyed the solar panels. The antenna was replaced in time to receive data from Landsat 7. The addition of a radome makes it appear even more prominently in the 2002 photo. A 5.4 meter back up antenna was added a short time later.

A 2022 image brings us up to date on the history of this half-section of land housing the USGS remotely sensed image archive that supports studies of land change over time. It can even take us back to the past for documenting change.

Africa, the second largest continent, is a mix of steamy rainforests, vast grasslands, and arid deserts. It has no long mountain ranges, but is home to the world's largest hot desert, the Sahara, and its longest river, the Nile. The featured area is the central South Atlantic coastal region of Namibia, including the cities of Walvis Bay and Windhoek.

Large-scale draining of the marshes began in earnest after the Gulf War of 1991. Water from the Tigris and Euphrates rivers was redirected to bypass the marshes. A west-east canal, 40 kilometers long and 1–2 kilometers wide, connected to the north-south Prosperity River, the prominent canal in the middle of these images. Even wider than the west-east canal, the Prosperity River is basically a massive moat that captures water from the rivers and tributaries and prevents it from flowing into the marshes.

Throughout the 1990s, the marshes declined dramatically. The loss of vegetation and water is widespread and clear to see in the images. The extent of the marshland was reduced by about 85% by 2000.

The Agno River is located on the island of Luzon and is the fifth largest river system in the Philippines. Over 2 million people live in the Agno River Valley. The first image was acquired by Landsat 8 in June 2013. The second image (Landsat 7) shows the November 2013 flooding caused by Typhoon Haiyan (Yolanda).

The Landsat satellites collect imagery worldwide on a daily basis, and can help measure and monitor the landscape changes caused by devastating storms.

These two Landsat images show the expansion of agricultural fields along the Chira River in northern Peru. The green of irrigated fields contrasts against the arid background of the land in this coastal region. The main crops in this region include rice, cotton, maize, mangoes, and lemons.

The new agricultural areas in the second image (2014) are supported by irrigation from the Chira River and Poechos Reservoir in the upper right portion of the images. The reservoir and its system of dams were developed to generate electricity, control flooding, and support local irrigation needs.

Landsat imagery is often used to monitor the status and changes of agricultural land use and water resources over time.

Irrigated agriculture in the valley, shown by the red field patterns, has increased. This agriculture depends on rainfall captured in the mountains and channeled to the valley floor, as well as nearby rivers and drilled wells.

The area of vegetation just outside the delta northwest of Cairo is new agricultural development, with some of the crops irrigated through center-pivot irrigation. The most common crops grown are cotton, rice, corn, potatoes, oranges, and wheat. Although areas at a distance from the Nile often are not able to be irrigated, land that does support crops produces high yields and is harvested two or three times in many years.

Food shortages have been documented for thousands of years in Egypt, and they can still cause problems. As the Egyptian population grows, producing enough food has become more difficult, so the government subsidizes food to make comfortable life possible. One staple food highly subsidized in Egypt is bread. The "bread riots" in 1977 and 2008 were the result of a reduction in those subsidies.

Despite government regulation that keeps the production of non-food crops like cotton low, Egypt still imports much of its food, especially wheat. This can increase the price of food even higher.

Dams being built on the Nile River and its tributaries upstream from Egypt could affect the amount of water making its way to Egypt.

The fertile muck soils along the south shore of Lake Okeechobee in the Everglades Agricultural Area are intensively farmed. Tomatoes, beans, squash, peppers, and other crops are grown during the winter and shipped north. Sugarcane is the main crop there from spring through the fall.

The bottom center of the later images reveals the location of Stormwater Treatment Area (STA) 3/4, one of six STAs mandated by the State of Florida’s Everglades Forever Act, passed in 1994. STA 3/4 is distinct from the polygons of the agricultural area. Just to its west is Holey Land Wildlife Management Area.

These constructed wetlands are designed to remove phosphorus that comes from agricultural runoff. Under previous agricultural practices, phosphorus from fertilizers was allowed to run off into the Everglades. Phosphorus is an essential nutrient, but too much of it alters the Everglades’ natural habitats.

These treatment areas channel runoff through shallow marshes filled with plants that absorb phosphorus, reducing the amount that flows into the Everglades. The plants include cattail, southern naiad, hydrilla, and algae. These plants continue to absorb phosphorus even after they die and decompose. The underlying limestone layer then holds the phosphorus, providing long-term storage.

Besides helping to restore the Everglades, these treatment areas have become a great home for wading birds, ducks, and alligators. Florida offers hunting and other recreational opportunities at many of these treatment areas.

Akpatok Island lies in Ungava Bay in northern Quebec, Canada. Accessible only by air, Akpatok Island rises out of the water as sheer cliffs that soar 500 to 800 feet (150 to 243m) above the sea surface. The island is an important sanctuary for cliff-nesting seabirds. Numerous ice floes around the island attract walrus and whales, making Akpatok a traditional hunting ground for native Inuit people.

Southeast of Riyadh, irrigation has clearly increased over time, particularly around the city of Al Kharj. The red circles are fields with center-pivot irrigation systems, drawing water from Saudi Arabia’s aquifers. This irrigation development resulted from the investment of part of Saudi Arabia’s oil revenues in an effort to modernize agriculture.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Alabama is the only state in the country that contains all of the major natural resources needed to make iron and steel. It is also the largest supplier of cast-iron and steel pipe products.

One of the factors that improves on Landsat sensors over the project’s history is the quality of the data. For example, compare these images of glaciers in Alaska’s Chitina River Valley from 1980. There is more background noise in an RBV image than there is in the MSS image. The RBV on Landsat 3 had a slightly higher spatial resolution, but the low signal-to-noise ratio makes it harder to pull out surface detail.

The 2018 image from Landsat 8’s Operational Land Imager has even better signal-to-noise ratio and higher resolution than both early sensors. The image reveals more detail about the roughness and flow of the ice. Landsat 8’s shortwave infrared bands provide a better distinction between ice and rock or soil.

High-quality data is needed in studying glaciers. Glaciers reflect visible light and appear bright white in natural color satellite images. But a glacier absorbs near-infrared light. The near-infrared and shortwave infrared imaging on later Landsats show the difference between snow and bare ground more clearly.

However, glaciologists still found RBV useful for mapping arctic regions. In high latitudes, images acquired at low sun angles helped enhance local topographic relief. The high resolution of the RBV on Landsat 3 supplemented MSS imagery.

In the RBV image of the Chitina River Valley, the brightest wavy streaks are glaciers. Note that they extend farther downstream in 1980 than they do in 2018. In the Landsat 8 image, wavy blue streaks indicate glaciers. They are generally in the same location as in the 1980 image, just diminished.

While RBV might not be exactly what is needed or have the ideal attributes for a study or for mapping forests, glaciers, and other land covers, perhaps it’s one more tool to add to the collection in studying land change. It’s at least worth another look. Besides, as Faundeen said, “RBV is another interesting chapter in the Landsat story.”

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Alaska has 17 of the 20 highest peaks in the United States. Denali is the highest peak in North America at 20,320 feet above sea level. Denali, the native name for the mountain, means “The Great One.”

When the Earth shook Alaska 52 years ago—on Good Friday, March 27, 1964—tsunamis wiped out entire villages. Landslides swept Anchorage neighborhoods into Cook Inlet. A collision of tectonic plates comprising the planet’s outermost layer had caused a 9.2 magnitude earthquake, the largest in U.S. history, and killed 131 people.



Aerial photographs archived at the USGS Earth Resources Observation and Science (EROS) Center capture the quake’s dramatic impact on Anchorage’s coastal boundaries. In the 1953 image, the Turnagain neighborhood west of the city’s downtown area is only beginning to emerge from the trees along the inlet. Eight years after the disaster, in 1972, the wooded shoreline has vanished, the bluffs now submerged in a sediment band created by the cataclysmic actions of the temblor. Yet extensive new development shows that Anchorage continued to expand in this area.



These are just two of the 6.5 million aerial photographs that span the last 80 years and are available on the USGS EarthExplorer Web site. Along with millions of other data files in the EROS archive that have been acquired from satellites, airborne radar, and the U.S. space program, these aerial photographs tell an important and compelling story about land cover that is ever changing, both in the United States and around the globe.

These cloud formations were seen over the western Aleutian Islands. Their color variations are probably due to differences in temperature and in the size of water droplets that make up the clouds.

Algae blooms commonly happen in summer on Lake Erie, but the blooms have been increasing in recent years. This year, north winds pushed the algae toward the water intake system for Toledo, Ohio, the urban area visible in the lower left of these Landsat 8 images.

Certain types of freshwater algae produce a toxin that can be harmful to people. Whether harmful or not, algae blooms are often large enough to appear in satellite images. This Lake Erie bloom shows up as green swirls on the surface of the water in the August 1 image.  The white spots above the land and water are clouds. The June 14 image is displayed for comparison.

Scientists often use satellite imagery (such as Landsat) along with aerial imagery and water-based sensors to monitor the algae blooms each summer. The information helps them determine the type and distribution of the algae. Furthermore, comparing the annual extent of  the blooms helps scientists monitor long-term trends and predict the impacts and movement of future algae bloom events.

What look like pale yellow paint streaks slashing through a mosaic of mottled colors are ridges of wind-blown sand that make up Erg Iguidi, an area of ever-shifting sand dunes extending from Algeria into Mauritania in northwestern Africa. Erg Iguidi is one of several Saharan ergs, or sand seas, where individual dunes often surpass 500 meters-nearly a third of a mile-in both width and height.

This abstract in browns and grays from central Algeria shows that some parts of Africa's Sahara Desert contain much more than dunes of wind-blown sand. Barren ridges and fragmented mountains (lower right) border a vast expanse of arid plains etched with a complex system of dry streambeds. The streambeds contain water for brief periods following rare, intense rains that often cause flash floods.

A vast alluvial fan blossoms across the desolate landscape between the Kunlun and Altun mountain ranges that form the southern border of the Taklimakan Desert in China’s XinJiang Province.

The Shishaldin Volcano on the eastern edge of Alaska’s Aleutian Island chain erupted with activity in January of 2020.

The eruption on the island of Unimak sent an ash cloud five miles into the sky on January 7, forcing ash alerts for aviators, mariners and residents of nearby communities.

Landsat 8 captured both day- and nighttime imagery of the event as it happened. The first image in this series shows the volcano in August of 2019, a period of relative calm after a series of low-level eruptions the previous month.

A more explosive event began shortly after the new year. The island’s northern coast is just barely visible in the cloudy daytime image from January 7, but the satellite’s infrared and shortwave infrared bands capture the intensity of the Shishaldin’s eruptive heat as a flaming burst of red.

The nighttime image collected hours earlier is even more stark. The satellite’s thermal and infrared sensors depict the crater’s heat signature as a colorful orb. Zooming in, the heat signature is apparent.

Satellites such as Landsat are valuable tools to scientists studying volcanic activity from afar.

The study of the Earth's natural life cycles is known as phenology. Scientists track the emergence of shoots and leaves, blooming flowers and pollinators as phenological signals every spring. 

Spring has sprung earlier than usual in much of the United States this year. The USA National Phenology Network notes that much of the country has seen spring come 3 to 4 weeks faster than normal. Parts of the southeast have seen their earliest blooms in 39 years. 

Phenology is tracked by a network of observers but satellites like Landsat can also highlight the impact of an early spring. This area near the border of North and South Carolina is among those seeing its earliest leaf-outs and blooms on record. There's little difference between the 2020 and 2018 images in natural color, but Landsat's infrared and red bands can tease out the change through a greenness indicator called the Normalized Difference Vegetation Index, or NDVI. The early spring shines through clearly with NDVI. Areas with middling greenness in 2018 have brighter signals in 2020. Lakes, rivers, floodplains and marshes show the most vivid change. 

This image isolates the areas that saw higher NDVI. The green gradient represents healthier plant life, with the darkest areas showing the highest spikes. Most citizens can't run satellites, but they can contribute their observations to the Phenology Network. The non-profit group welcomes contributions from volunteers of nearly any age, through its Nature's Notebook program.

Many of the world’s highest peaks are the barely tallest points of high ranges, but Kilimanjaro stands alone, 15,000 feet above the surrounding plains. It actually has three peaks from three old volcanoes: Kibo (2), Mawenzi , and Shira.

In these Landsat images, concentric rings show the vegetation zones around this unusual peak. The bare summit is surrounded by low grass and shrubs. These transition to a band of forest, protected as a reserve, which appears bright green. Below this is a densely populated agricultural area, appearing as speckled light green in the Landsat images. And at its base, the mountain turns dry again, supporting fewer plants and people.

People have farmed the lower slopes for at least 2,000 years. In the last century, the mountain’s population has grown rapidly—about tenfold between 1910 and 2000. These people raised cattle, fruits and vegetables, and coffee. Prevented from migrating upslope by the forest/wildlife preserve, people have moved out into drier areas.

Vivid colors belie the arid landscape of northern Chile where the Atacama Desert, one of the world's driest, meets the foothills of the Andes. Here salt pans and gorges choked with mineral-streaked sediments give way to white-capped volcanoes.

Play this animation to see the change in this area happen from 1975 to 2017. The animation uses a Landsat image from most of the years in this time period to demonstrate the rapid rate of deforestation. Huge areas of Rondônia's dense rain forest transform to cleared areas in only a few decades. Unseen in these images are the effects of the deforestation on wildlife habitats and local and global climate.

The coal mines in the PRB advance quickly enough to see a lot of change from year to year. Two animations available here show the annual change of the mines in the regions.

The first animation shows almost one image per year back to 1984 of both the Black Thunder and North Antelope Rochelle Complex Mines. The second one listed is a close-up of the North Antelope Rochelle Complex and covers the same time period.

The date of each image appears in the lower right corner.

1. PRB coal mines: 1984–2018
2. North Antelope Rochelle Complex Mines: 1984–2018

In the flooded season, this part of Mali’s landscape stands out as bright green against the arid brown African Sahel. The Niger River and the Inland Delta have been an important water supply in the southern Sahara for thousands of years.

The river channels, lakes, swamps, and floodplains provide the main livelihoods in the delta: livestock, fishing, and farming. The delta is also a refuge for many migrating birds. After rice farming and livestock, fishing is the most important industry of the delta. The catch varies from year to year depending on water levels. An overall decrease in available water in the delta directly affects the population in this industry.

This series of images shows that the extent of the seasonal flood can vary. For example, 1984 was a low flood year, and the green extent in the image is smaller than it is for 1999. Another low water year was 2011. Exceptionally high floods can damage habitats and irrigation, but extremely low flows like those in 1984 can be disastrous. The loss of livestock caused by the lack of water one year can have long-lasting effects.

Two main threats to the region are inadequate water management and climate change. With growing water use and a predicted decrease in rain in the Sahel, the river flow of the Niger is expected to decline. The livelihoods of the delta’s people could be at risk.

Diverting upstream water for irrigation means less water for the delta. For example, the Fomi Dam in Guinea is being planned. The two countries are working on assessing the possible risks and benefits of the dam.

(Black stripes run through the 2011 image because of the Scan Line Corrector failure on Landsat 7 in May 2003.)

Antarctica’s interior is circled by glacial ice flows that move outward from the frozen continent’s surface.

Imagery collected over Antarctica by satellites like Landsat is typically marked by highly reflective snow and ice, but isolated pockets of wind-swept glacial ice glow with a distinct blue.

This stunning Landsat 8 image was acquired on February 18, 2018. It shows the Queen Fabiola Mountains, a 50-kilometer range that slows glacial movement and pushes stagnant blue ice to the surface. Swirling, textured turquoise surrounds the peaks and snow that remain during the Antarctic summer.

Blue ice forms when air bubbles are squeezed out of compressed snow and firn layers, which are layers of partially-compacted snow left over from previous seasons.

The ice appears blue as a result of the absorption of solar radiation at yellow and red wavelengths. Deeply penetrating light is uniformly scattered at blue wavelengths by the enclosed air bubbles.

Blue ice areas are also noteworthy for their role in preserving fallen meteorites. Over time, the ice has trapped and preserved asteroid fragments, and scientists frequently scour these areas to collect them.

Antarctica has been the source for a host of fascinating satellite imagery in recent months. We've offered scenes from the southern solstice, images of icebergs adrift, and shots of pooling meltwater during some of the warmest days on record for the frozen continent. 

An international team of scientists onboard a U.S. research vessel recently made another discovery related to polar warming trends. An uncharted island.

Landsat, as it turns out, had been watching the island for years. It emerged slowly from a stretch of coast between the Thwaites and Pine Island glaciers in West Antarctica. Landsat imagery shows it fully detached in 2014. At its widest, the granite outpost measures less than 400m across.

In February, the crew of the Thwaites Glacier Offshore Research Project, or THOR for short, became the first humans to see the island for what it was. The crew dubbed it Sif Island, after a Norse goddess of Earth and wife to Thor.

It’s winter in the Northern Hemisphere. But in Antarctica, summer has just begun. The summer solstice occurred at Zucchelli Station on December 22, 2019, at 5:19 p.m. local time. The high temperature that day was a balmy 34 degrees Fahrenheit.

These images from Landsat 8 show the distinct difference in sun angles caused by the change in seasons. The September image is from close to the equinox. Shadows are longer, causing the scene to be darker overall while revealing the ruggedness of the mountains.

The December image is brighter, with shorter shadows and much less sea ice.

Landsat images are useful for monitoring changes to sea ice and glaciers on the frozen continent, at least during summertime in the Southern Hemisphere.

Antelope Valley in southern California is the western part of the Mojave Desert. The San Gabriel Mountains and the Tehachapi Mountains give the valley a triangular shape. The southern edge of the valley is the San Andreas Fault.

While farming is going on in the valley in the more traditional sense, with irrigated fields showing up as bright green circles or rectangles in these Landsat images, farming of a different kind is also going on. With average annual wind speeds of 14 to 20 miles per hour and plenty of clear, sunny days, this part of the desert is on the cutting edge of wind and solar power.

(The small burn scar seen in the 2023 image is the Danny Fire, which burned almost 1,600 acres.)

The prominent crimson streak in the center of this image represents the remains of an extensive lava and mud flow. Its source is the currently dormant Anyuyskiy Volcano orange circular shape at the right end of the streak) in northeastern Russia. Remote and largely inaccessible, the region is a rugged collection of towering volcanic peaks, steep valleys, and wild, snow-fed rivers and streams.

Mangroves in the Ayeyarwady Delta are also being replaced by aquaculture. In the southwestern part of the delta, brackish shrimp pond development is expanding. The dark blue shapes in the images represent the shrimp ponds. Not as much land is being taken up by aquaculture, but this industry is growing.

While some mangroves have been restored on the delta, the aquaculture, agriculture, and cutting activities need to be monitored so that the benefits of mangroves can be maintained. Researchers continue to use Landsat and other remote sensing information to monitor this region.

Brazil's Araca River is a tributary of the Negro River, which feeds into the Amazon.

We see a lot of change with 50 years of Landsat imagery, along with the declassified satellite imagery in the archives at EROS. The drying of the Aral Sea is likely the most dramatic change occurring over the past several decades in this imagery.

The Aral Sea once covered about 68,000 square kilometers, a little bigger than the U.S. state of West Virginia. It was the 4th largest lake in the world. It is now only about 10% of the size it was in 1960. Coastlines receded several kilometers from what were once coastal communities.

The Aral Sea is a terminal lake. Large permanent snow fields and glaciers in mountain ranges feed the two major rivers that flow into it, but it has no outlet. Syr Darya flows into the northern part of the Aral Sea. Amu Darya flows into the southern part. (Darya means river in the Turkic languages of central Asia.)

The precipitation rate over the Aral Sea is very low, less than 200 millimeters per year. However, 1,000–1,200 millimeters of water evaporates from the sea each year. Therefore, stability of the water level greatly depends on inflow from these two rivers, which has diminished over the past few decades leading to the shrinking of the lake.

The sea has in fact split into two separate bodies of water, referred to as the North Aral Sea and the South Aral Sea. The North Aral has stabilized but the South Aral has continued to shrink and become saltier. Up until the 1960s, Aral Sea salinity was around 10 grams per liter, less than one-third the salinity of the ocean. The salinity level now exceeds 100 grams per liter in the South Aral, which is about three times saltier than the ocean.

The effects of this dramatic change are far-reaching, geographically, environmentally, and economically. The subsequent sections describe how a body of water this size could nearly disappear so quickly.

The city of Aralsk is shown in the 1964 ARGON image on the coast of the sea. By 1977, the sea had retreated from the city but was still just a few kilometers away. As depicted in the 2015 image, Aralsk sits nearly 20 km from the water’s edge.

Commercial fishing in the Aral Sea peaked in the late 1950s. With the drop in water levels and rise in salinity, the fish that once thrived in the sea could not survive. As a result, commercial fishing was no longer sustainable by the early 1980s.

With the recovery of the North Aral, commercial fishing has started up again. It’s still just a fraction of what it was in the 1950s, but Aralsk is again processing fish at a new plant, established after the completion of the Kok-Aral Dam in 2005. Aralsk is not the thriving city it once was, but the return of the North Aral gives residents some hope of recovery.

Heavy rains in late December 2016 and early January 2017 are affecting soybean production in Argentina’s bread-basket provinces while impacting soy prices worldwide.



Landsat 8’s Operational Land Imager is a valuable tool for confirming weather’s impact on crop production. While rainfall is common in northeastern Argentina from December through February each year, the flooding of soybean fields in that area is dramatic in the January 2017 Landsat image, compared to a similar period in January 2015, when no such inundation covers the landscape.



The flooding in the world’s third largest soybean-exporting country caused soybean and soymeal prices to hit six-month highs in mid-January on the Chicago Board of Trade, commodity analysts said. Argentina’s Rosario Grains Exchange has reported that almost 4 million acres of soybeans in that country were damaged by this recent flooding. This image shows a portion of that inundation.



As the longest-running satellite system covering the Earth, Landsat is vital to national and international food production. The Landsat imagery not only helps verify crop damage, as it did in this case, but is also valuable to agencies like the U.S. Department of Agriculture for formulating reports on crop production, condition, progress, and projecting yields.

 

The early images show main roads cutting through the forest. Highway 421 snakes through the forest south-southwest from the city of Ariquemes, and Highway 364 runs roughly north to south through Ariquemes. More roads branch out from the main ones to create the fishbone pattern. As time goes on, a patchwork of cleared areas, forest remnants, and settlements is left behind.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Arizona is blessed with many natural wonders including the Grand Canyon, Lake Powell/Rainbow Bridge, Petrified Forest/Painted Desert, Monument Valley, Meteor Crater, and Superstition Mountain.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Arkansas, officially “The Natural State,” is a state of mountains, valleys, dense woodland and fertile plains. Its clear lakes and streams and abundant wildlife help to make tourism one of the state’s most important industries.

The bodies of water further south, east of Tampa, look completely different, because they have a much more human origin: phosphate mining.

South of Orlando lies the world's most productive source of phosphate, a critical nutrient for modern agriculture. In these images, plants look red and phosphate mines appear as a bright, high-contrast mix of white bare earth and blue-black ponds. The images show the phosphate region expanding, as more lands were put through the cycle of mining and reclamation.

Under just the right conditions, some ocean sediments (like those forming limestone) become rich in phosphorus. Ideally, an upwelling of cold, phosphorus-rich water to the shallow waters near shore stimulates all forms of sea life, from algae to animals. Their shells and bones, plus crystals of phosphorus, concentrate phosphorus on the ocean floor. Moving water—tides and currents underwater, streams and floods above sea level—sorts the heavy phosphate pebbles from the lighter sands, further concentrating the valuable nutrient.

Many glaciers around the world are losing ice mass and retreating. One such area is the Southern Patagonia Icefield (SPI) in Chile. However, one glacier in the SPI is actually defying the worldwide trend. The Pio XI Glacier is advancing, and based on scientific studies, there is no clear reason why.

Pio XI flows from the SPI toward the west then splits into two fronts. From 1998 to 2014, the southern front advanced 593 meters. The northern front, which flows into Lake Greve, advanced 107 meters in the same time period. This pair of Landsat images shows that all of the other glaciers that flow down from the SPI into Lake Greve are retreating.

The complex behavior of glaciers involves more than just measuring where the ice ends. Scientists theorize that something is happening inside or beneath Pio XI to make it advance, rather than an external factor like climate. The glacier flows from a wide accumulation area into a narrow outlet, and the depth of the lakes it flows into, along with the speed of the glacier’s flow, may also be factors.

Whatever the cause, glaciers continue to be closely monitored, and in the remote region of the SPI, that monitoring needs to be done with remote sensing. Landsat offers several observations per year in these areas and will help scientists understand the glacier’s future behavior.

The Mississippi River Delta region in southern Louisiana is losing land to sea level rise, subsidence, and hurricane damage. The mouth of the Atchafalaya River, a distributary of the Mississippi River, is an exception. It has been building two deltas for the past several decades. The Atchafalaya Delta exemplifies the importance of freshwater and sediment to maintaining and even building land in the delta region.

The Atchafalaya River branches away from the Mississippi River where the Red River joins it. The Atchafalaya takes about 30% of the combined flow of both rivers and carries the water and sediment south.

Just east of the Atchafalaya basin, land is rapidly disappearing from the Louisiana coast. Besides subsidence, sea level rise, and hurricanes, a lack of sediment input from the Mississippi River is also causing land loss, making the region more vulnerable to storms.

Besides the risk to wildlife habitats, coastal Louisiana supports more than 30% of the commercial fisheries in the United States, and five of the country’s top 20 ports are located there. Furthermore, in 2017, the USGS reported that a fifth of the country’s oil and gas is transported through the southern Louisiana wetlands.

The time series of Landsat imagery shows that the deltas do not progressively extend into the Gulf. They are affected by local conditions like tides and the timing of hurricanes and floods. So while the overall trend is extension and delta building, the deltas seem to temporarily contract at times. In the Landsat images, water is dark blue, and vegetation is green.

One of the world’s largest reserves of oil sits under the boreal forest of northwestern Alberta, Canada. The deposit covers about 142,200 square kilometers (54,900 square miles), an area a little larger than the U.S. state of Wisconsin.

Known as the oil sands region, it accounts for the largest segment of Alberta’s economy. According to Alberta Energy, proven reserves in the oil sands in 2016 were 165.4 billion barrels.

This series of imagery focuses on the largest of the three oil sands areas in Alberta, the Athabasca region. Located just north of Fort McMurray along the Athabasca River, the mining of the Athabasca region has grown dramatically over the last three decades.

These are the Anti-Atlas Mountains, part of the Atlas Mountain range in southern Morocco, Africa. The region contains some of the world's largest and most diverse mineral resources, most of which are still untouched.

Auckland is on the North Island of New Zealand along the Hauraki Gulf. The urban area (purple hues) can be seen on the left side of this image. The round island north of the city that appears darker than the others is a volcanic island (Rangitoto Island) within the Auckland volcanic field.



As one of the few cities in the world to have two harbors on two separate bodies of water, the city has grown to become the largest and most populous in the country. Manukau  Harbor is to the southwest of the city and opens into the Tasman Sea. Waitemata Harbor, along the city’s north shores, opens into the Pacific Ocean. On the right side of this image  is the Firth of Thames, a bay important for habitat and  wetland conservation.



The Landsat 8 Operational Land Imager (OLI) captured this image on September 2, 2013.

Australia is the smallest, and flattest, of all the continents. Its surface details are largely the result of erosion. Many rivers drain into the continent's harsh, arid interior, where they terminate in salt lakes that are dry for most of the year. Australia's coastal regions, however, are famous for astounding biodiversity, from the Great Barrier Reef in the northeast to Shark Bay in the west.

Within the Hamersley Iron Province in Western Australia, Landsat's shortwave infrared and near-infrared detectors highlight different types of rock. The oval in the upper center part of the image is a geological feature called Rocklea Dome. The dark meanders within the dome are channel iron deposits.

The Ayeyarwady Delta—also called the Irrawaddy Delta—is a vast alluvial floodplain. The delta spans over 35,000 km² (13,500 mi²) and was once home to an extensive tract of mangrove forests, but deforestation has changed the landscape. One scientific study estimated that the delta lost 1,685 km² (651 mi²) from 1978 to 2011. This 50-year sequence of Landsat images shows the relatively rapid loss of mangrove forest.

The most noticeable land change in these Landsat images is simply the addition of land itself. In Bahrain, a nation of 36 islands in the Middle East, the sea is shallow enough along the northern and eastern coast to make the addition of land relatively inexpensive.

The main Bahrain Island is about 990 square kilometers; however, it took less than two decades for the coastal zone of Bahrain to increase by about 40 square kilometers. All of this added land is dredged from the seabed in massive land reclamation projects.

Besides the large land additions, an obvious increase in urban areas dominates the images. Bahrain’s 1970 population was 213,000; in 2014 it was estimated to be 1,316,000. The country’s urban extent doubled between 1987 and 2013.

Even though oil is underground, Landsat images can reveal related land changes on the surface. The Bakken oil boom has made North Dakota the second leading oil producing state—behind only Texas. Evidence of this boom is apparent on the landscape.

The focus of this oil boom, which began around 2008, is on the Bakken formation of western North Dakota, northeastern Montana, and part of Canada. The Bakken formation constitutes one of the largest deposits of oil and natural gas in the United States. The Bakken is part of the larger Williston Basin, which, according to a 2013 USGS study, has 7.4 billion barrels of oil that is recoverable using today’s technology.

These Landsat images show the increasing number of oil platforms over just a few years, along with associated infrastructure changes. The overview images in this introductory section show the entire region that will be discussed in more detail in the following subsections.

The North Dakota oil industry took off in the 1950s. When oil prices dropped in the 1980s, that boom ended. Oil prices recovered by 1990, but the current boom didn’t hit until the technology of hydraulic fracturing, or fracking, came along in the 2000s. By 2008, drilling in North Dakota surged like never before and oil production increased dramatically.

The oil and natural gas within the Bakken are locked in a rock formation. Fracking uses a mix of water, salt, chemicals, and sand to fracture the rock. The fractured rock allows the oil to flow to the well.

The price of oil crashed again in 2014, halting most of the drilling. But this was only after North Dakota’s oil industry reached the milestone of producing 1 million barrels per day. In mid-2017, oil prices recovered to around $50 a barrel, stabilizing the situation in North Dakota.

The large Landsat 8 image shows the full extent of Bangong Lake, which means “long neck swan” in Tibetan. It is located partly in China and partly in the region of Kashmir that is controlled by India. The lake is approximately 155 kilometers (96.3 miles) long from east to west. It reaches only 5 meters (16 feet) wide at its narrowest point.

This lake is unique in that the eastern portion has fresh water, while the waters to the west are saline.

The two smaller Landsat images show the easternmost portion of Bangong Lake. Changes to the local shoreline can be seen by comparing the two images, acquired in 1998 and 2013. During this time period, changing conditions have expanded the lake area, particularly along the marshy southwest and northern shorelines. These shoreline changes can affect the local salinity levels, which in turn may affect the vegetation and biological balance of the area.

The 40-year archive of Landsat imagery is useful in documenting change to the Earth’s landscape.

San Juan, Argentina, nestles in a fertile valley flanked by arid mountains. Croplands and vineyards (green) abut the metropolitan area on the San Juan River. The white "teardrop" (lower left) is an ancient lakebed called Barreal Blanco. It is one of the best places in the world for carrovelismo, or landsailing, thanks to the steady winds that sweep across this flat, unobstructed expanse of hard-packed sediment.

An increasingly large gash has opened up in northern Russia’s Siberian tundra. During the past few decades, warmer summers and shorter winters have caused permafrost in this region to thaw, which then allows the warmed soils on slopes to slump and erode.

Dozens of the resultant channels and craters are spread across Siberia, but the biggest is Batagaika Crater, about 10 kilometers southeast of the town of Batagay. The Landsat image series shows the initial gash widening from a narrow channel in 1991 to a crater with steep-sided cliffs by 2017, at a resolution of 30 meters. Sentinel-2A’s 10-meter resolution in the natural color bands provides a more detailed look at the crater.

This so-called “megaslump” is being enlarged on a hillslope that leads down to the floodplain of the Batagay River. As the active soil slumps, more of the surrounding and underlying frozen soil is exposed and melts, causing the land to slump further and the extent and speed of the permafrost thawing to increase. Based on satellite image records, the crater is expanding by more than 10 meters per year.

The crater is now about 800 meters wide and up to 86 meters deep. It has exposed older frozen soil horizons that represent a history of environmental changes that span more than 50,000 years. The Landsat and Sentinel missions help track the changes to the crater as scientists study the permafrost and the environmental history now exposed.

Sometimes described as resembling a stingray or a tadpole, the Batagaika Crater is a widening chasm in Siberia and the world’s largest permafrost crater.

Multiple satellites have recorded the crater’s growth, from declassified satellite imagery collected in the 1960s to current multispectral sensor images from Landsat and Europe’s Copernicus Sentinel-2 satellite, to build a continuous view over the last 60 years.

Each exposed layer of the crater wall is like a snapshot in time, helping scientists understand the past climate. Layers of permafrost exposed at the bottom might be up to 650,000 years old. Scientists have also discovered mummified wildlife in the crater. In 2018, the remains of a 42,000-year-old foal of an extinct horse species were found.

Why this matters

As frozen permafrost soils thaw, they release carbon dioxide, methane, and nitrous oxide—greenhouse gases that fuel global warming.

Comparing the 1984 (high water level) and 2005 (low water level) images, there is a pale outline along many parts of the lake. When the water level drops, canyon walls that were once inundated are exposed again.

Referred to as the “bathtub ring,” this pale outline shows when the lake is below capacity. Calcium carbonate and other mineral compounds, many of them various salts in the water, attach themselves to the sandstone and leave behind this white mark. The top of the white mark is the high water mark. The only time the bathtub ring is not visible is when the lake is completely full.

Before 1950, the entire basin was covered by Bear Glacier and ended at a terminal moraine. By 1961, a small lake had formed, referred to as Bear Glacier Lagoon. By 1984, the size of the lagoon had doubled. It has continued to grow quickly as the glacier has retreated over time. People can now go kayaking among the icebergs on Bear Glacier Lagoon.

In August 2014, water from Bear Glacier Lagoon breached the moraine that separates the lagoon from Resurrection Bay. Lake levels dropped by 1–2 feet (0.3–0.6 meters). These glacier lake outburst floods occur regularly. The breach is visible in the extreme close-up in the 2014 Landsat image, in which different infrared wavelengths were used to make the breach more visible.

Bear Glacier is located on the Kenai Peninsula near Seward, Alaska.

This glacier represents one of over 30 glacial outflows for the nearby Harding Icefield, which covers over 700 square miles (1,800 square km).

Bear Glacier has been receding dramatically over recent decades, as shown in this series of images. The black and white aerial photograph mosaic was collected in 1950 and shows the glacier extending almost fully across the highlighted region (red outline). The satellite images (color) were acquired by Landsat 4 (1989), Landsat 7 (2001), and Landsat 8 (2013). Taken together, these images show an overall trend of glacial retreat in this area for the 63-year time period.

There are millions of aerial and satellite images held in the USGS archives, which provide important historical and current views of Earth’s changing landscape. These images are public and available for download by anyone for any location worldwide.

This glacier represents one of over 30 glacial outflows for the nearby Harding Icefield, which covers over 700 square miles (1,800 square km).  Bear Glacier has been receding dramatically over recent decades, as shown in this series of images. The black and white aerial photograph mosaic was collected in 1950 and shows the glacier covering almost the entire area within the highlighted region (red outline). The satellite images (color) were acquired by Landsat 4 (1989), Landsat 7 (2001), and Landsat 8 (2013). Taken together, these images show an overall trend of glacial retreat in this area for the 63-year time period.  There are millions of aerial and satellite images held in the USGS archives, which provide important historical and current views of Earth’s changing landscape. These images are public and available for download by anyone for any location worldwide.

Satellite images of Earth help us observe locations that can be difficult to reach in person. Glaciers are sensitive to changes in regional and global climate, so scientists want to monitor them regularly. While some scientists study glaciers in the field, the Landsat satellites allow many others to monitor glacial change from the comfort of their office.

Bear Glacier is an outlet glacier of the Harding Icefield in Kenai Fjords National Park, Alaska. Glaciers form when fallen snow compresses into an ice mass over many years; the process usually takes centuries. The ice then flows to lower elevations. Besides showing visible retreat over the past few decades, Bear Glacier has also thinned about 2.5 feet (0.75 meters) per year from the early 1950s to the 1990s. 

Since Bear Glacier and many other remote glaciers are largely inaccessible, satellite images provide important insights into how they change over time.

(Black stripes run through some of the images because of the Scan Line Corrector failure on Landsat 7 in May 2003.)

Ice covering Beaufort Sea near the Arctic Ocean typically reaches full-blown breakup by late May each year as air and water temperatures warm, and as daylight turns longer. But 2016 has been dramatically different.

This year, significant breakup and fracturing of the sea ice had occurred by mid-April, as seen in these Landsat 8 images acquired almost exactly a year apart. On April 13, 2015, the ice is largely intact, though fracturing has begun. A year later, on April 15, 2016, much more open water is visible.

Ice specialists with NASA say this year’s breakup is attributable to unusually warm air temperatures during the first months of the year, and to strong winds caused by a stalled high-pressure system over the area. The same warmth that fueled the massive Fort McMurray wildfire in northern Alberta earlier in May is part of the weather pattern affecting the Beaufort Sea.

Though the region was once covered by thicker, multi-year ice, it now has largely seasonal, first-year ice that is thinner, weaker, and more easily broken up by strong winds. While the early breakup hints to the possibility that 2016 could ultimately witness the lowest sea ice extent in the history of satellite recording, that, of course, will depend on the weather conditions in the coming months. Future Landsat acquisitions will help scientists monitor the area and visualize changes.

Earth Science reminds us that the study of Earth and its biological processes can occur anywhere—whether we realize it or not. An easy way to appreciate science is illustrated in these images vividly portraying the life cycle of vegetation and displaying seasonal change at an area within the Great Smoky Mountains National Park along the Tennessee–North Carolina border.

Earth’s constant biological changing resonates in a revolving gallery of seasonal brushstrokes across the park’s landscape. The vibrant green of forest life explodes as trees still dormant in April awaken and reach full bloom by the time summer stretches into September in these false-color images from Landsat 8’s Operational Land Imager.

By late October, senescence has begun—trees brushed in autumn colors start to shed their leaves. While the dark green of coniferous forests remains constant, as it does all year, the start of winter in December ushers back the pink hues of nature in slumber, surrounded by leafless, dormant deciduous trees.

Ponderosa pine forests in the Black Hills of South Dakota are the focus of this week’s USGS Image of the Week.

Mountain pine beetles are about the size of a grain of rice, so of course we can’t see them from space in satellite images. What is visible is what the beetles can do to a pine forest. The washed-out pink color indicates large areas of standing dead or damaged trees.

Cold winters normally kill beetle eggs and keep the population down. Recent winters have been warmer than normal. Prolonged dry conditions in the early 2000s also weakened the trees and made them easier for the beetles to attack. These factors together led to a massive epidemic.

In 2018, precipitation in the Black Hills was above normal, and the beetles have remained at normal levels. The damage is done, however, and current Landsat imagery still shows the degraded forest.

Landsat is well suited to studying forest change over large areas. The Landsat record covers more than 46 years, and its visible and near-infrared range can pinpoint the beginning of future beetle attacks.

For more details on the pine bark beetle infestation in the Black Hills, see the USGS Earthshots page.

Beijing has grown and changed remarkably in the "reform era" since 1979, in its own distinct pattern. U.S. cities, for example, are often shaped like a circus tent, with a sharp peak of skyscrapers in the center, sloping off to mid-rise buildings and then low suburbs of single-family houses. Beijing, in contrast, is bowl-shaped, with low historic buildings in its center, surrounded by many commercial skyscrapers and residential towers. Height restrictions have limited many buildings to 3 stories within 250 m of the Forbidden City, 10 stories within the Second Ring Road, and unlimited stories beyond. And single-family buildings are rare in Beijing, except in recent western-style suburbs built for foreigners.

Several distinct dynamics have shaped Beijing's growth. The state built a great deal of housing in Beijing during the 1950s, but little was built in the 1960s and 1970s, partly to discourage migration to the city. In the 1970s, many people who spent the Cultural Revolution in the countryside returned to Beijing, and others came seeking jobs. Married couples increasingly sought their own home after marriage rather than living with their parents. By the late 1970s, housing was scarce and crowded. In 1979, along with new reforms, came a boom in housing construction that was much-needed. Beijing's 2021 population is estimated at just over 19.4 million, with a population density of just over 4,600 people per square km.

In the more socialist era of 1949–1979, most Beijingers lived and worked in the same place. These "work units" included communal dining halls and infirmaries. So the city was not highly differentiated into office, shopping, industrial, and residential areas. There were few reasons to travel across town often. This has also changed in the reform era; housing is typically still tied to a job, especially for the many state employees, but this housing is not at the workplace. Many work-units buy floors of apartment buildings, or other blocks of housing, so many coworkers live together.

In the 1980s, many industrial plants were moved from the central city to outlying areas. Much of the new housing was also outside the Third Ring Road, in medium- and high-rise buildings often built on former agricultural land. In the central city, office districts and shopping districts have been built or expanded. Many new buildings serve the increasing number of foreigners doing business in Beijing.

Partly because people's daily activities now occur in separate parts of the city, traffic has increased greatly, and congestion is a major problem. An extensive subway line now operates in Beijing. By 2010, the Beijing subway network had 14 lines, 198 stations, and 336 km of track.

The Chinese government has provided a bicycle renting system in Beijing to try to relieve traffic congestion. But car use has risen dramatically in the last decade, and city planners are planning around the automobile and building expressways.

These images show the growth of Beijing from 1977 to 2022. In the images, the blue tones representing buildings and pavement spread outward, replacing the red tones of natural and agricultural vegetation. The city has now grown far beyond its traditional core around the Inner City, which is visible as a bright rectangle in the zoom-in images.

Like sweeping brushstrokes of pink and green, the Belcher Islands meander across the deep blue of Canada's Hudson Bay. The islands' only inhabitants live in the small town of Sanikiluaq, near the upper end of the middle island. Despite the green hues in this image, these rocky islands are too cold to sustain more than a smattering of low-growing vegetation.

During the aquaculture expansion of the 1980s, cropland in the fertile valley was converted to catfish ponds. After the decline, many ponds returned to cropland. Some were left unused.

The Landsat images from 1972 and 1986 show that impressive expansion. Based on the 1972 image, which is coarser resolution than the later Landsat imagery, the land was either cropland or flat wetland before the catfish ponds were constructed.

Near Belzoni, Mississippi, many ponds have partially converted to cropland. According to the USDA Cropland Data Layer, the region shown in these images has converted to cotton, corn, soybeans, and rice growing. There are also woody wetlands in the former ponds.

The 2021 images span the seasons to show which areas have converted back to cropland. Actively growing crops appear bright green in the summer images. Those fields turn a washed-out pink after harvest. The areas that remain dark green in the fall are forested. By winter, those areas, too, become a faded brown and are the first areas to green up again in spring.

Where the water disappears throughout the 2021 images may be rice fields. Places where the water persists all year are catfish ponds.

Tourism is now a major part of the local economy. Ten thousand visitors climb the mountain every year, employing local people as porters and guides. The snow and ice are part of what attracts the tourists, some of whom come as a “last chance” opportunity, believing that the glaciers will soon disappear. Scientific estimates of that date vary, and some believe the glaciers on the side slopes may survive. If the glaciers do disappear, seasonal snow will still whiten the peak, but perhaps not in the dry seasons when most tourists come. In the end, on this mountain both science and economics are always drawn back, as if by some powerful cultural gravity, to the famous white landscape on its peak.

Besides hydropower, the dam has made river navigation easier. The river is now deeper and slower, allowing larger ships to travel on the river from Shanghai, at the river’s estuary, all the way to Chongqing, over 373 miles (600 kilometers) upstream from the dam. The Landsat images show straight lines next to the dam—the lock system that raises and lowers ships past the dam.

Historically, the Yangtze River has flooded catastrophically. The floods have caused thousands of deaths and damaged agricultural land. Flood control is one of the major anticipated benefits of the dam. The overall long-term extent of this benefit can be determined in the future as a wider range of high water levels are experienced on the river. In addition to flood regulation, water from the reservoir has been used to irrigate dry farmland during drought.

However, the project came with some downsides, including the relocation of over 1 million people. Other dangers added to the project’s criticisms. For example, much less sediment now reaches the lower portions of the river, which affects the intertidal wetland habitat at the river’s delta.

The reservoir’s water level is allowed to go down in summer to accommodate floodwaters. The water level rises again at the end of summer. These periodic water pressure changes destabilize the surrounding slopes, increasing the likelihood of landslides. Furthermore, the added weight of the reservoir’s water may be intensifying local fault activity; since the reservoir filled in 2003, seismic activity has increased.

The reservoir could also affect precipitation in the region. The lake effect in this mountainous region can be enhanced; moist air is forced upward as it reaches the shoreline, adding to low stratus clouds and fog. Additionally, the enhanced evaporation because of the lake can create a microclimate with different precipitation patterns.

In Montana, wildfire swept across Flathead Lake's 30-acre Bird Island in early August of 2020.

Landsat 8 captured this imagery one day after the fire began.

The satellite's short wave infrared and near infrared bands reveal the active fire covering approximately half of the island. Smoke obscures the remainder. The same band combination highlights healthy vegetation 16 days earlier.

Landsat 8 data archived at the USGS Earth Resources Observation and Science Center is a powerful tool for monitoring the impact of wildfires in the U.S. and around the world.

The oil type mined in the Athabasca oil sands region is bitumen. This naturally occurring oil is so viscous that even at room temperature it acts like cold molasses.

The oil sand is quartz sand; each grain of sand is surrounded by a thin film of water, and then covered in the heavy oil. The bitumen is too thick to flow or to be pumped without first being heated.

Of the three oil sands areas in Alberta, only the Athabasca region has reserves shallow enough for surface mining. The Athabasca River, over tens of millions of years, eroded away the sediment that covered the bitumen, making it reachable. Surface mining causes a larger and more visible disturbance of the land surface than other types of mining. The surface mineable area there covers about 4,800 square kilometers (1,850 square miles).

We can’t see bugs from space, but we can see the effects of insect infestation in Landsat imagery. An unprecedented mountain pine beetle epidemic started in the Black Hills of South Dakota in 1996 and has damaged about 430,000 acres of forest land. The pine beetle, about the size of a grain of rice, is killing ponderosa and other pines throughout the Black Hills.

Normally, the mountain pine beetle contributes to the health of a forest by infesting and killing older and stressed trees, which helps make the forest more productive. However, the recent large outbreak is doing more harm than good. It can affect water quality. It can convert the forest from a carbon sink to a carbon source. And where insect outbreaks and forest disturbance caused by wildfire overlap, the effects can actually be both harmful and beneficial. All of the effects of an outbreak need to be monitored.

Mountain pine beetles usually live in small numbers. It’s normal for the population to boom occasionally, but the current epidemic is unprecedented. Beyond the Black Hills, pine beetle outbreaks have occurred extensively in many pine forests throughout western North America, from British Columba in Canada to New Mexico.

In these Landsat images, beetle infestation is typically indicated by a washed-out pinkish color as seen in the top center and lower right of the images. The more pronounced pink region in the lower left of these images is a burn scar from the Jasper Fire, which occurred in 2000.

In a desolate corner of Nevada, a playa surrounded by rugged mountains and described as dry, dusty, desolate, and devoid of vegetation comes to life the week before Labor Day every year for a unique arts festival.

Black Rock Playa in northwestern Nevada is part of the lakebed of ancient Lake Lahontan, a deep lake that existed as recently as 15,000 years ago. Lake Lahontan left fine sediments on the lake bottom to form the extremely flat surface. According to a detailed topographic study, the elevation of the playa varies by just 1 meter over 310 square kilometers.

The playa stretches 56 kilometers from the small town of Gerlach toward the northeast and the edge of the Black Rock Range.

Rainfall is rare during summer when daily high temperatures regularly exceed 37°C, making the surface hard-packed and dusty. Snowmelt flows into the playa in the spring to smooth out the surface. The clay minerals on the lakebed expand when wet and then contract as they dry to form a cracked pattern.

Black Rock Playa is managed by the Bureau of Land Management (BLM) as The Black Rock Desert–High Rock Canyon Emigrant Trails National Conservation Area.

The Black Thunder Mine, shown in the series of Landsat images on the left, has sent 2.2 billion tons of coal to U.S. power plants since 1977. It produces 4 tons of coal per second.

The images show the expansion of the open-pit mining operations at Black Thunder. The black lines are the coal seams, the layers of coal that formed over time and lie under the land surface. Lighter straight lines are stepped benches that allow trucks to drive in and out of the mine.

Snow covers the landscape in southwestern Minnesota just a day before the winter solstice. It may look like a stark black and white image, but it is really a natural color image. The Minnesota River flows from the upper left to the lower right.

A feathery, blood red streak cuts across the heart of this image. The translucent red paint stroke is not actually a feature of the land. It is a cirrus cloud detected by Landsat 8’s cirrus band. This cirrus cloud, which hovers over the Aral Sea in Kazakhstan, is invisible in natural color imagery.

Near the Queen Fabiola Mountains, also called the Yamato Mountains, is a classic example of blue ice in Antarctica. Blue ice emerges where wind scours glaciers clean of snow and forms when air bubbles are squeezed out of layers of partially compacted snow left over from previous seasons. The ice appears blue because red and yellow wavelengths of light are absorbed. Deeply penetrating light is uniformly scattered at blue wavelengths by the enclosed air bubbles.

The Turpan Depression, nestled at the foot of China's Bogda Mountains, is a strange mix of salt lakes and sand dunes, and is one of the few places in the world that lies below sea level.

Once a vast carpet of healthy vegetation, the Amazon rain forest is changing rapidly. This image of Bolivia shows dramatic deforestation in the Amazon Basin. Loggers have cut long paths into the forest, while ranchers have cleared large blocks for their herds. Fanning out from these clear-cut areas are settlements built in radial arrangements of fields and farms. Healthy vegetation appears bright red in this image.

The other major natural harbour on the south end of these images is Botany Bay. The runways of Sydney Airport stretch into the bay. The main north-south runway is 3,962 meters long and was built in 1963. The other runway that extends into the bay appears in the 2002 image; it was completed in 1994.

Another expansion seen in Botany Bay is Port Botany, a major shipping port for Australia. The port is in an ideal location because of the deep water channels of the bay and proximity to the open waters of the Tasman Sea. The most recent addition is seen in the 2013 image, which shows the development of 63 hectares of land.

The coal-fired Boundary Dam Power Station began operations in the early 1960s along the Souris River near Estavan, in Saskatchewan, Canada.

These three Landsat images were acquired in 1972, 1986, and 2013 and show how the landscape has been changing over the years.

The Boundary Dam and Reservoir (near the left-center of the first image) was constructed in 1957 to provide coolant for the coal-fired power station operations. The 1986 image shows expansion of coal mining operations into the surrounding area. The 2013 image shows the Rafferty Dam (upper left), which was developed in the late 1980s and early 1990s to provide additional water for the area and reduce downstream flooding along the Souris River. This image also shows further expansion of the coal mining operations, as well as the emergence of many temporary lakes which began to develop during the wet spring of 2011.

The Landsat archive contains more than 40 years of data that are useful for land change analysis, covering all areas of the globe. Landsat provides scientists and project engineers with invaluable imagery to conduct their research on how the changes affect the landscape.

Rising unexpectedly from the heart of the Namib Desert in northern Namibia, the Brandberg Massif is an exhumed granite intrusion. Unique plant and animal communities thrive in its high-altitude environment, and prehistoric cave paintings decorate walls hidden in its steep cliffs.

Two dams at an iron ore mine in southeastern Brazil broke on November 5, 2015, sending mine waste cascading into nearby valleys. The muddy floodwaters destroyed hundreds of homes in the village of Bento Rodrigues, which lies in a valley below the mining area. Natural color images from Landsat 8 compare how the area looked before the breach in the dams to how it looked one week after the incident.

The orange colors along the left side of the images are open pit iron ore mines. The dams burst from the tailings ponds, which hold mine waste. The November 12 image shows the orange sediment flowing down a valley through the dark green rain forest. This sediment may contain mining chemicals that could affect the fertility of downstream farmland. Researchers are still testing the water to get a better idea about the contents of the mine waste.

On November 5, 2015, a tailings pond dam failed at an iron mine in southeastern Brazil, sending contaminated water sediment through the nearby village of Bento Rodrigues and into tributaries of the Rio Doce (Sweet River). (See http://eros.usgs.gov/imagegallery/image-week-2#Brazil_Images) The sediment from that disaster has since moved downstream to the mouth of the Doce River.



The Landsat 8 image from September 11, 2015, shows what the mouth of the Doce River looks like under normal conditions. A Landsat 8 image acquired on November 30 shows a plume of sediment flowing into the Atlantic Ocean. This may be contaminated sediment from the dam breach. Advanced Landsat 8 capabilities, including the new coastal aerosol band and superior instrument performance, may improve monitoring the extent of sediment flow in the river.

The Breiðamerkurjökull glacier tongue, one of the largest in Iceland, flows from Vatnajökull, Iceland’s largest glacier. According to descriptions in historical accounts, this glacier tongue advanced toward the Atlantic Ocean up until the turn of the 19th century. Since about 1930, it has been in full retreat.

In these false color Landsat images, vegetated land surfaces appear red. Snow and ice are white. The Vatnajökull glacier is the bright white area in the upper left. Outlet glaciers streak away from it toward the Atlantic Ocean in the lower right. Breiðamerkurjökull is the largest glacial tongue on Vatnajökull and is featured in the center of these images.

(Black stripes run through the 2006 image because of the Scan Line Corrector failure on Landsat 7 in May 2003.)

Cities that are growing this rapidly must also show accompanying infrastructure changes. The additions of bridges, highways, railroads, and airports are intended to merge the cities of the delta into a single megalopolis.

One ambitious project is the Hong Kong-Zhuhai-Macau Bridge, which opened in 2018, to connect the three cities and cut the travel time from Hong Kong to Zhuhai from 3 hours to 30 minutes. Visible as a long, thin line across the bay, the bridge-tunnel system includes 42 kilometers of bridges over water and a 7-kilometer tunnel. The tunnel allows ships to enter and exit the bay and runs between two artificial islands. The entire system is about 15 times longer than the Golden Gate Bridge. The total cost of bridge was $7.56 billion.

Built to withstand an 8.0 earthquake, the bridge makes it easier for goods from the entire PRD to be transported to Hong Kong’s international airport for export. Speaking of the airport, a third runway was added north of the existing runways, 3,800 m long and built on 650 hectares of reclaimed land.

The natural color image from Europe's Copernicus Sentinel-2 satellite shows the bridge at 10-meter resolution. Ships are visible in the water, including the wakes behind the ships.

Building Sea City is a massive and challenging engineering project that requires constant innovation. As seen in the 1994 image from Landsat, the area is a natural estuary with tidal creeks. The design of Sea City follows these existing tidal creeks to bring water inland from the Gulf.

The first phase of construction began in 2003. The 2004 Landsat image shows the first artificial waterway. Eventually, the sea will be brought inland to the desert by about 9 kilometers on what was once desolate unusable salt marsh. The lagoons created are 3–4 meters deep on average.

The water in the lagoons needs to be flushed and kept circulating so it doesn’t become stagnant. With the Gulf’s tidal range of 2.7 meters, this flushing happens in the waterways of Sea City naturally. Farther inland, however, tidal action needs a little help. Giant gates help control the flow of the tides and ensure circulation of the entire lagoon system. It works like a natural pump. Testing of the seawater has shown that its quality is excellent.

These Karman vortices formed over the islands of Broutona, Chirpoy, and Brat Chirpoyev (Chirpoy’s Brother), all part of the Kuril Island chain found between Russia's Kamchatka Peninsula and Japan.

One of the most studied ice shelves in Antarctica has recently seen big changes. While the calving process is a normal part of an ice shelf’s lifecycle, recent rifting and iceberg calving may mean that the Brunt Ice Shelf is in a period of instability. It could also be an indicator of the future of other ice shelves in this region.

Landsat satellites have watched the ice shelf for nearly five decades. In 1971, a calving event reduced its extent. This occurred just before the first Landsat launched in 1972, so the earliest Landsat observations of Brunt came during the Antarctic summer of 1972–1973.

And now, Landsat 9 has joined Landsat 8 in observing the changing rifts on the ice shelf.

The smaller city of Buraydah, northwest of Riyadh, shows the same pattern of urban growth and agricultural development. From 1972 to 1986, the population of Buraydah almost tripled, from 60,000 to about 180,000 people. The rapid growth continued, and the population was 378,422 in 2004 and 669,000 in 2020. The 48-year increase is over 1,000%.

New roads are visible in these images, and irrigated land has increased. Buraydah and Riyadh both lie in Saudi Arabia’s central corridor of settlement and development.

After a wildland fire, scientists at the USGS EROS Center quickly begin working on preliminary soil burn severity assessments. They provide results of this work to Department of Interior (DOI) Burned Area Emergency Response (BAER) teams and other local federal land managers. BAER teams consist of an interdisciplinary group of scientists that evaluate the effects of wildland fires and develop mitigation plans to protect valuable natural resources, protect human life and property, and promote landscape recovery.

“The soil burn severity map is a critical component for many of the BAER team postfire hazard mitigation prescriptions,” says Randy McKinley, a geographer with the USGS EROS Center, who routinely maps fires on DOI-managed lands for the Bureau of Land Management, National Park Service, Bureau of Indian Affairs, and the U.S. Fish and Wildlife Service.

The burn severity map, also called a Burned Area Reflectance Classification (BARC) map, is created using digital image processing techniques developed by USGS, USFS, and other scientists. The BARC is a preliminary soil burn severity map that is field validated and refined by the BAER team. The final map provides a synoptic view of large fires that is not easily obtained in a timely manner on the ground.

The BARC map is made by comparing NIR and SWIR spectral band values. NIR light is largely reflected by healthy green vegetation. SWIR light is largely reflected by ash and bare soil. The burn map exploits the relationship between these two bands. The best way to do this is to measure the relationship between these bands prefire and then again postfire. The areas where the relationship between the two bands has changed the most are most likely to be severely burned. The areas where that relationship has changed little are likely to be unburned or very lightly burned.

For example, Landsat 8 helped map destruction caused by the Cougar Creek fire near Mount Adams, 75 miles northeast of Portland, Oregon, which started on August 10, 2015. In the three images to the left, snow appears cyan on its peak. The postfire Landsat image from September 11, 2015, shows where the previous green vegetation south and east of the mountain is now charred and appears in shades of red. In the burn severity map, dark green is non-burned, light blue is low burn severity, yellow is moderate severity, and red is high.

The timely delivery of BARC maps, generally in less than 2 days after image acquisition, would not be possible without the USGS capability to efficiently downlink, process, and distribute Landsat and other satellite data. USGS hydrologists and soil scientists routinely request BARC products to obtain a better understanding of postfire erosion and water quality issues. McKinley adds, “BARC maps have also proven to be a crucial data layer for the modeling and prediction of potentially destructive postfire debris flows.”

EROS responds to dozens of requests for burn mapping support each year. It’s not possible to get such a quick and complete assessment without satellite imagery. Landsat’s 30-m resolution is optimal for providing the detail suitable for landscape scale wildland fire mapping. When Landsat data are not available, imagery from the NASA EO-1 satellite, ESA’s Sentinel-2, and satellite sensors such as Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Moderate Resolution Imaging Spectroradiometer (MODIS) provide options for developing a complete picture of landscape change caused by wildland fire.

On August 10, 2015, the Soda Fire began burning about 8 miles northeast of Jordan Valley, OR. It spread rapidly because of high winds, parched fuels, triple digit heat, and low humidity. Over 283,000 acres had burned by August 20.



On the morning of August 22, Landsat 7 captured a postfire image (left) of the Soda Fire burn scar. This image was used along with a prefire image from Landsat 8 to derive a Burned Area Reflectance Classification (BARC) map.



The BARC map (right) was created using digital image analysis techniques developed by USGS, USFS, and other scientists, and it allows a synoptic view of fire extent and severity. The map is preliminary and has not yet been field-validated.



This type of detailed information would be difficult to obtain in a timely manner based on ground observations alone. Reflecting the amount of vegetation loss caused by the fire, the colors on this map show that the Soda Fire was mostly classified as low and moderate severity (light green and yellow), with few high severity areas (red).



EROS scientists respond to dozens of requests for burn mapping support each year. It would not be possible to obtain a rapid and complete assessment without satellite imagery, and Landsat’s 30-meter resolution provides the detail needed for rapid landscape-scale wildland fire mapping.

 

A unique event takes place every year on the playa. Burning Man is a weeklong arts and culture festival that ends on the Saturday of Labor Day weekend with the burning of a huge wooden effigy.

Part of the event is the construction of a temporary metropolis named Black Rock City. Building of the temporary town starts about 6 weeks before the event. This is the most visible product of the event in satellite images.

Besides the city’s radial roadways, the images show a pentagon surrounding the city. This “trash fence” catches wind-blown garbage to keep it from spreading throughout the playa. A major policy of Burning Man is to leave no trace. All debris must be cleaned up after the event is over. Participants must pick up all MOOP, which stands for Matter Out Of Place. The BLM, which grants the license for the event, monitors the cleanup.

A Landsat 8 image from October 16, 2018, shows not only the temporary nature of the metropolis but also that cleanup is evidently still in progress on that date.

Burning Man began in 1986 in California with 20 attendees and a 2.4-meter effigy. The festival’s first year at Black Rock Playa was in 1990, when the event had outgrown its California beach location. The temporary city that year had a population of 350 and the effigy was 12 meters tall. The 2018 event included 70,000 people. In recent years, the height of the entire effigy has exceeded 30 meters.

Usually located in the southern portion of the playa, the festival location changes slightly every year. Can you find the festival location in the 1996 image? (Look in the upper right of that image.) How about in 1999? (Extreme southwestern part of the playa.)

The city becomes easier to spot as the event grows larger. In the 2018 image, Black Rock City spans nearly 5 kilometers across. But its area covers only about 3 percent of the entire playa.

Burning Man went virtual in 2020 due to COVID-19. Its temporary city was absent from satellite imagery on Labor Day weekend for the first time in decades. After another year without a festival on the playa in 2021, Burning Man returned in 2022.

Check out this hi-resolution aerial image from the National Agriculture Imagery Program (NAIP) of Burning Man 2019.

Every year, tens of thousands of people descend upon an unforgiving windswept playa in northwestern Nevada to build a city.

Within months, the city is gone.

Burning Man is named for the wooden effigy set ablaze at the end of the weeklong celebration in the temporary metropolis of Black Rock City.

It all happens on an ancient alkali flat nestled between mountain ranges that fills with runoff after snowy winters.

Band 7 of Landsat 8’s Operational Land Imager is sensitive to moisture in and above the soil. It makes the silty water that runs through the playa on May 22, 2017 pop in bright aqua.

The city was built months later. The 7-mile pentagonal “trash fence” that catches wind-blown waste and the city’s radial roadways are clearly visible in this image from August 26.

The winding white road leading into Burning Man stands out against a light blue gray streak on the playa.

It all disappears quickly. The revelers who call themselves “burners” are expected to leave no trace as they depart. Organizers begin to tear down and haul away structures after the Labor Day finale.

By October 29, only a rough outline of Black Rock City remains.

Landsat imagery offers a unique tool to track both natural and man-made land change throughout the year.

Truly a river of ice, Antarctica's relatively fast-moving Byrd Glacier courses through the Transantarctic Mountains at a rate of 0.8 kilometers (0.5 miles) per year. More than 180 kilometers (112 miles) long, the glacier flows down from the polar plateau (left) to the Ross Ice Shelf (right). Long, sweeping flow lines are crossed in places by much shorter lines, which are deep cracks in the ice called crevasses. The conspicuous red patches indicate areas of exposed rock.

Several hundred kilometers southeast of Buenos Aires, Cabo San Antonio juts out into the Atlantic Ocean along the Argentinean coast.

As expected in the Atacama Desert, Landsat doesn’t detect much vegetation—only some green along the Río Loa and next to the city of Calama. Calama has seen a rising population because of the influx of mine workers. The images show this visible urban area expansion. Notice the airport expansion that took place between the 2010 and 2016 images.

The Caldor Fire in California started on August 14, 2021 and quickly spread in high winds. The fire continues to expand toward the Lake Tahoe area as residents evacuate.

The first image was captured on August 21, the 8th day. Landsat 8's near infrared and shortwave infrared bands reveal active fire, burn scars, and smoke.

Landsat's thermal and infrared bands also expose the fire's advancing edge at night time. The second image is from August 29th, 15 days after ignition.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

The highest and lowest points in the continental United States are located within 100 miles of each other in California: Mount Whitney (14,494 feet) and Death Valley (282 feet below sea level).

Satellites have captured views of the numerous major fires burning in California.

An image acquired on November 9, 2018, from NASA’s MODIS sensor on the Terra satellite shows smoke pouring out of two major fires, the Camp Fire and the Woolsey Fire, which both ignited the day before.

In the north, the Camp Fire quickly became the deadliest wildfire in the state’s history. Landsat 8 captured an image of the fire hours after it started, and intense northeasterly winds and dry fuels caused the fire to spread rapidly. The Camp Fire burned over 100,000 acres in just two days.

Over 6,500 homes were destroyed, most of them in Paradise, a city of 27,000 people.

In southern California, Santa Ana winds fanned the flames of the Woolsey Fire. This fire has burned over 97,000 acres.

The enormous fire scar is the maroon color between the urban areas of Los Angeles, Thousand Oaks, and Malibu. The scar from the Hill Fire is also visible to the northwest.

When it comes to forest loss on a global scale, Cambodia is notable for how rapidly its forests are being cleared.



Among countries with accelerated rates of deforestation—Sierra Leone, Madagascar, Uruguay, and Paraguay among them—Cambodia ranks above them all with an annual loss of 14.4 percent of its forests between 2001 and 2014, according to researchers at the University of Maryland, who used Landsat data to track their rates. In that time period, Cambodia lost 5,560 square miles of forests.



That loss is easily seen in these Landsat images. The Landsat 5 image captured in 1999 (left) shows vast dark green forest among a mountainous area of Cambodia. The 2017 image acquired by Landsat 8 (right) reveals areas where forest has been clear-cut. The bright green landscapes in the lower left interspersed with darker blocks are crops. The pinkish-tan areas are old, small-plot agricultural areas, and the bright green rectangles (top left) are agroforestry areas where rubber or oil palm plantations have emerged.

 

Working with Landsat data and other economic datasets, researchers at the University of Maryland have demonstrated that changes in global rubber prices and a surge in land-concession deals have helped accelerate Cambodia’s rate of deforestation. The Cambodian government leases concession lands to domestic and foreign investors for agriculture, timber production, and other uses.

Named after the ancient Mayan Province of Kimpech, the state of Campeche comprises much of the western half of Mexico's Yucatan Peninsula. Rivers in southern Campeche drain into the immense Terminos Lagoon, the entrance to which is protected by a long barrier island, Isla Del Carmen.

Look at the zoomed in images by the coast. Can you tell the peaks (that is, the ridges) from the valleys? It may seem easy, but you may be tricked by a common optical illusion in satellite images called relief inversion.

All Landsat images are designed to be morning views, so all of these images were taken in the morning. The Sun is to the east and south, so these images are lit from below and to the right. This causes the western and northwestern slopes to appear dark because they face the sun less squarely, and so are less illuminated.

However, we unconsciously expect to see images lit from above. This tricks the brain into believing that mountains are valleys or that craters are mountains. If you look at the image upside-down, with the sun angle generally from the top of the image, you will probably see the image differently.

On the east end of the largest portion of the Danjiangkou Reservoir, a bright line extends to the east and north. This canal takes water from the reservoir 1,400 kilometers to Beijing. This water will benefit over 100 million people.

Construction of this central route of the South-North Water Transfer Project began in December 2003. Beijing began receiving water from the reservoir via the canal in 2014. The entire project is the biggest interbasin transfer scheme in the world.

Historically, water flowed slowly southward through the Everglades in a wide swath. Record floods in 1947 and 1948 led to the construction of a massive flood control project. It served to prevent flooding and store water during dry periods. It also allowed for further development of the growing urban area on the Atlantic coastal ridge.

The project established three Water Conservation Areas (WCAs), one of which is the Loxahatchee National Wildlife Refuge. These areas are delineated in the Landsat images, clearly divided by the levees and canals. Also visible are the Big Cypress National Preserve, Everglades National Park, and Everglades Agricultural Area.

Another part of the project is the 100-mile-long eastern perimeter levee, a 3- to 6-meter high earthen berm built to prevent flooding of farmland and urban areas. It runs along the eastern edge of the WCAs, marking a clear separation between the WCAs and urban areas such as Miami, Fort Lauderdale, and Coral Springs.

Along with facilitating the further growth of the urban areas of greater Miami, the other upshot of the project was that the natural flow of water was interrupted, changing the hydrology of the region. The gradual sheet flow of freshwater is diminished, and instead sudden pulses of water are delivered by the canals. These sudden releases caused decreases in the numbers of fish species.

Known for its beaches and resort hotels, Cancun lies at the tip of Mexico's Yucatan Peninsula. Inland from this tourist mecca, however, lies a sparsely populated tropical scrub forest that shelters the ruins of ancient Mayan cities.

The Green River and the Colorado River meet within Canyonlands National Park in Utah. Snow-covered Mount Waas, shown in light blue on the right side of the image, overlooks the arches, canyons, and bizarre rock formations that prevail throughout this region.

Along some coastlines, long, narrow islands stand guard. These barrier islands are attractive to tourists, but they also protect the mainland coast from storm surge and are important beach, dune, and marsh habitats. Those islands do take a beating though.

These images focus on the southeastern elbow of Cape Cod, Massachusetts. Wave action, currents, winds, and tides are constantly changing the barrier islands here. Strong storms can change them quite suddenly.

In 1984, a nearly unbroken barrier island lines the Massachusetts coast at Chatham. To the south, Monomoy Island extends into the ocean like a teardrop. The other subsections of this Earthshots page show over 35 years of changes to these barrier islands as seen by three different Landsat satellites.

Marking part of the boundary between Colombia and Venezuela, the Meta River resembles an artery among capillaries within the human body. Those capillary-like features actually depict dense tree cover along the numerous streams that flow among rich tropical grassland.

The Caicos Islands (pronounced KAY-kohss) in the northern Caribbean are a popular tourist attraction, renowned for their beautiful beaches, clear waters, scuba diving, and luxury resorts. The islands lie primarily along the northern perimeter of the submerged Caicos Bank (turquoise), a shallow limestone platform formed of sand, algae, and coral reefs covering 6,140 square kilometers (2,370 square miles).

In shallow waters surrounding the Tyuleniy Archipelago in the Caspian Sea, chunks of ice were the artists. The 3-meter-deep water makes the dark green vegetation on the sea bottom visible. The lines scratched in that vegetation were caused by ice chunks, pushed upward and downward by wind and currents, scouring the sea floor.

Farming doesn’t always mean tilling the ground for crops. In the flat valley along the Mississippi River, in a distinctive region of northwestern Mississippi referred to as “the Delta,” rich soils do support agriculture. But the flat land and abundant groundwater are also suited to aquaculture. Aquaculture simply means cultivating aquatic plants or fish for food. In this part of Mississippi, it means catfish farming.

Catfish are raised in Arkansas and Alabama, but Mississippi has led the nation in catfish production since the 1980s. The farm-raised catfish eat high-protein food pellets made of soybeans, corn, wheat, vitamins, and minerals. The pellets float on top of the water, so the fish don’t eat like wild bottom-feeding catfish do. The result is healthier fish with a cleaner, milder taste.

The Mississippi River meanders down the left side of these Landsat images. Green indicates vegetation: Bright green shapes are cropland, and darker green shades are forests. Surface water is dark blue. Besides the Mississippi, other streams and oxbow lakes are scattered across the region. The catfish ponds are the distinctive blue squares and rectangles among the cropland. The washed-out pink areas are harvested fields.

The catfish industry grew rapidly in the 1980s and 1990s. The blue-tinted shapes in the Landsat images mark the ponds where the whiskered fish are raised. The ponds are built above ground with levees, and the water in the ponds is 4–6 feet deep.

Catfish pond acreage reduced by more than half from 2003 to 2013. Rising costs and low-priced imports from China and Vietnam led to the decline.

At the same time, increased productivity from technological efficiencies led to higher yields and less land needed for the ponds. Among those efficiencies was the development of a hybrid catfish species, a mix of Ictalurus punctatus (channel catfish) and Ictalurus furcatus (blue catfish).

The hybrid grows faster, is easier to harvest, and has greater tolerance to crowding, so less area is needed to grow more fish. The business term for that is “increased operational intensity.”

Other technological efficiencies reduced costs and spurred growth in the 2010s, including electric paddlewheel aerators, automated oxygen monitors, and pumps to circulate the water. Ponds are now divided into separate sections for treating wastewater and for the fish. These split ponds make treating the water more efficient.

Mississippi leads the U.S. in catfish production. The blue tinted shapes in these Landsat images mark ponds where catfish are raised.

Ponds are build above ground with levees. The ponds are 4 to 6 feet deep. Catfish pond acreage dropped by more than half from 2003 to 2013. Many ponds returned to cropland. Some were left unused. Others transitioned to woody wetlands.

Some of the dark lines in the images might look like roads. Those lines are a transportation network of sorts, just not transportation for people. They are cattle corridors that connect grazing lands (dark patches) and sometimes connect to villages. They are lined with hedges to keep the cattle out of the crops.

One line that goes all the way across these images is indeed a road. It passes through the city of Bankass. But the other lines are cattle corridors.

The diversion of water from the rivers for agricultural use is probably the most significant cause of Lake Urmia’s decline. Several dams have also been built on rivers that flow into the lake. Since 1996, droughts have further contributed to the lower lake levels.

Rainfall in 2018-19 brought water levels back up. That rainfall did not bring a permanent restoration of the lake, as the 2023 image shows.

No single fix can help the lake recover. But the continual monitoring from Landsat helps decision makers plan for the best solutions.

High-resolution imagery from the WorldView satellite and aerial photos show details that moderate resolution satellite imagery cannot. The result of the land loss and its effect on Isle de Jean Charles becomes clear in these images.

The loss of land in southern Louisiana has several causes.

• Dams Upriver, dams trap sediment that normally flowed to the delta and built it up.
• Subsidence The land in the Louisiana delta has always sunk naturally. Faults contribute to regional subsidence, and sediments naturally compress over time. Deposits flowing from the Mississippi River continually replenished and built up the land. Much of this sediment is now trapped by upstream dams, taking away the rebuilding process.
• Sea level rise The long-term gradual rise in sea level combined with that subsidence increases the land loss more than either factor alone.
• Canals 10,000 miles of canals dug through the marshland, built for oil and gas production activities, bring saltwater farther inland, which degrades freshwater marshlands.
• Hurricanes Storm surge and waves can propagate farther inland because of land loss, making matters worse. Hurricanes erode the soft land from the coast and can damage both vulnerable and healthy marshlands.

The saltwater that washes farther inland also invades the soil and has made the area no longer good for farming. As the marshland retreats, the saltwater enters bald cypress swamp and kills the trees.

Island Road
The only road into or out of the island is the 2-mile-long Island Road. When it was built in 1953, land and marsh surrounded it. Tribal members hunted and trapped on the land around the road. It now cuts across open water. It often submerges during high tide, and erosion continues to eat away at the roadbed.

On September 27, 2016, the Cedar River surged to a crest of 22 feet at Cedar Rapids, Iowa—6 feet above the river’s major flood stage designation. This inundation was a result of quick-moving storms that dropped about 10 inches of rain in the eastern part of the state recently.

 

Images from Landsat 8’s Operational Land Imager sensor show the dramatic transformation of the river as it flows toward Cedar Rapids. On July 8, 2016, the shallow river meanders into the city, surrounded by green crops in the heart of the growing season. The September 26 image shows the overflowing river at a time when magenta tones around it speak to a countryside preparing for the harvest.



Emergency crews erected nearly 10 miles of temporary flood barricades and laid 250,000 sandbags in Cedar Rapids to prepare for rising waters in the city. Authorities advised as many as 10,000 residents to evacuate as the Cedar River surged to levels exceeded only by the flood of 2008, when the water crested at a record 31.12 feet.

 

The ice surrounding the northern Canadian Spicer Islands, shown in bright red, resembles a cell, complete with ribosomes, mitochondria, and a nucleus. Even though the image was captured shortly after the first day of summer in the Northern Hemisphere, the islands are locked in ice.

If you could speed up time and watch a fast-growing city like Las Vegas change, what would it look like? From the perspective of the Landsat satellites, it’s a stunning lesson in urban growth. Watch Las Vegas’ rapid expansion in these Landsat images dating back to 1972.

In each image, bright red indicates actively growing vegetation. This makes golf courses easy to spot, and their development can be tracked along with the residential areas that surround them.

The desert landscape gradually becomes covered with streets, highways, and development as time goes on. A plot of very light tan can sometimes be seen right before a new residential area is built. This indicates a clearing of the land.

Other natural bright areas also appear around the urban development. The bright reflection indicates the presence of salts, minerals, and clays in the sediment. Water once settled in these flat, lower elevation areas and these minerals remained. The brown-tan regions surrounding the city are likely steeper slopes where flowing water rinsed out those minerals. Darker tones indicate coarser material, and lighter tones are fine material such as clays that have a higher reflectance.

Each image represents one year from 1972 to 2023. Landsats 1–5 and Landsat 7–9 are represented, which demonstrates the value of the past Landsat data along with new data for monitoring change over time. Landsat images are available to the public at no cost at the USGS Global Visualization Viewer (http://glovis.usgs.gov) or EarthExplorer (http://earthexplorer.usgs.gov).

Download a .wmv file of the animation here.

Recent activity has altered the landscape in northwestern China. Alluvial Fan, from the second Earth As Art collection, was acquired in 2002 by the ASTER sensor on NASA’s Terra satellite. It’s truly a fan favorite, often named one of the top images of the entire collection.

Around 2008, Landsat began to capture some activity on the northern end of the alluvial fan. The changes are clearly manmade, not natural phenomena.

Geographers at EROS say the change is due to a large irrigation scheme. A diversion channel now cuts across the fan and captures water from intermittent streams. The north side of that channel now features a flatter landscape rather than braided streams as the water is captured by the channel.

The dark rectangle is a water holding pond, and there are some structures near it as well. Off of the Earth As Art image to the north is a large area of irrigated farmland that was not present back in 2002. If we look closely, a pipeline extends from that holding pond to those fields.

Lake Urmia, located in northwestern Iran, was once one of the largest saltwater lakes in the Middle East. It supports an important seasonal habitat for many species of migrating birds.

In recent years, the lake has diminished dramatically. Water enters Lake Urmia primarily from rainfall and inflowing rivers. The diversion of water from local rivers for agricultural use is one likely cause of Lake Urmia’s decline. Since 1996, drought has further contributed to the lower lake levels. The lake now covers about 10 percent of the area it covered in the 1970s.

These Landsat images show the changes to Lake Urmia’s surface area over the past fourteen years. Each image was created by mosaicking several individual Landsat scenes to show the full lake area. From 2000 to 2010, some changes can be seen. In the final image (2014), the entire southern portion of the salty lakebed is now exposed.

Future Landsat imagery will continue to be a useful tool for mapping and monitoring of further changes to Lake Urmia and its surrounding areas.

The new shoreline extends east of the city all the way to the airport on the island’s tip. In the mid-1970s, the government moved the main international terminal from Paya Lebar to Changi, partly to allow more distance between the planes and new, higher skyscrapers downtown.

In the 1989 image, on the east end of the island, you can see the old and new runways, parallel and a few miles apart. Planes now land where once was only water. A further extension of the land on the eastern tip was built for Chengi Air Base, visible in the 2000 image and later.

A feature known as Chasm 1 is prominent in the Landsat imagery. This crack reactivated in December 2012 after no movement for 35 years. The Landsat images show rapid growth of the chasm, especially in 2018 and 2019, as it extended toward the McDonald Ice Rumples.

In early 2019, Chasm 1 was extending north as fast as 4 kilometers per year, and from 2012 to 2021, the rift widened almost three-fold.

On January 22, 2023, an iceberg the size of Houston finally broke off the shelf. Landsat images show the area a day before the break and a few days after. The new iceberg, named A-81, will be carefully tracked by satellites as it floats into the Weddell Sea.

The time series of images also shows Chasm 1 moving westward with the flow of the ice shelf.

The close-up Landsat images that accompany this section show an obvious checkerboard pattern in the forest. These lands are known as “O&C” lands, which stands for Oregon and California Railroad. Land granted to O&C in 1866 was every other square mile, which formed the checkerboard pattern seen in the imagery. These lands now belong to the federal government, managed by the Bureau of Land Management (BLM).

In these images, the squares that remain dark green generally are lands that belong to the BLM. In some of those squares, there is clearcutting and regrowth taking place in this time frame. Adjacent squares, however, have a more noticeable change in tan or white spots, indicating more frequent clearcuts in the logging/reforestation cycle.

View an animation of this area to see the changes as they happen.

A nuclear accident devastated the region near Chernobyl, Ukraine, on April 26, 1986. These images show the area around the nuclear power plant three days after the accident, and then years and decades after the accident.

The Landsat 5 image from April 29, 1986, was the first civilian satellite image of the accident. The data from Landsat were used to help confirm that an explosion had happened at Chernobyl and that the plant had been shut down.

Chesapeake Bay is the Nation’s largest estuary and its restoration and protection is a priority. The USGS provides scientific information to help manage this vital ecosystem. As part of that role, staff at the USGS Earth Resources Observation and Science (EROS) Center created this true color composite image. The image was created using Provisional Surface Reflectance data from five Landsat 8 scenes, acquired in October and November 2014.

Provisional Surface Reflectance processing includes atmospheric correction to reduce haze, aerosol, water vapor, and ozone effects from Landsat Level 1 processed data. The enhanced processing makes this seamless mosaic possible and provides a sharper view of the Earth’s surface, as if there were no atmosphere interrupting the view between the satellite and ground.

Chesapeake Bay is the dark shape stretching up through the center of the image. Sediment in the water appears either light blue or green. Baltimore, Maryland, and Washington, DC, are the two bright areas near the upper left. The peninsula across the Chesapeake from these cities is a patchwork of farm, forest, and protected areas.

All Landsat Surface Reflectance products are available through the EROS Science Processing Architecture (ESPA) On Demand Interface (http://espa.cr.usgs.gov) and EarthExplorer (http://earthexplorer.usgs.gov).



For more information, see http://landsat.usgs.gov/CDR_ECV.php.

 

Cheyenne Bottoms is the largest inland wetland in the United States. Water normally diverts from rivers into the vast marshland.

The wetland water level changes with precipitation and surface flows. For example, 2007 was a wet year. And 2013 was a dry year.

Heavy rains in late summer typically replenish the water levels in the marshland, making it a key stopover for thousands of migrating birds to eat and rest. In the fall of 2022, the birds found nothing to stop for. Landsat images show not only the lack of water, but also an overall lack of healthy green vegetation due to drought conditions in the region.

Cheyenne Bottoms in central Kansas is the largest inland wetland in the United States. A 41,000-acre natural basin, the wetland is a key stopover for a multitude of migrating birds to eat and rest. The Cheyenne Bottoms Wildlife Area covers nearly half of the basin.

The wetland’s water level changes with precipitation and surface flows. For example, 2007 was a wet year, and 2013 was a dry year until heavy rain in late summer partially replenished the marshland.

The lines in the basin are roads on top of dikes, built in the 1950s to impound water in five pools and manage water levels. Further subdivision of the wetland pools took place in the 1990s. Water levels in individual pools are periodically flooded or drained to control invasive vegetation (such as hybrid cattails) and promote desirable aquatic vegetation. Additionally, small grains such as Japanese millet are sometimes seeded to provide supplemental food resources, then flooded to make the food available to foraging waterfowl.

The crops surrounding Cheyenne Bottoms include alfalfa, sorghum, wheat, corn, and soybeans, along with pasture.

Two intermittent streams, Blood and Deception creeks, flow into the Bottoms from the northwest. Canals were built to divert water from the Arkansas River and Wet Walnut Creek to provide a source of supplemental water to the wetland. However, drought kept the Bottoms dry in 2022.

On the border between Chile and the Catamarca province of Argentina lies a vast field of currently dormant volcanoes. Over time, these volcanoes have laid down a crust of magma roughly 2 miles (3.2 km) thick. It is tinged with a patina of various colors that can indicate both the age and mineral content of the original lava flows.

The Atacama Desert of northern Chile has minimal vegetation. But it has ample mineral wealth: large amounts of copper, gold, silver, and other industrial metals. This includes the world’s largest open pit copper mine and the second deepest open pit—the Chuquicamata Mine.

In operation since 1910, the largest open pit at the mine measures 1 kilometer deep, 3 kilometers wide, and 5 kilometers long. New York City’s Central Park could fit inside it.

Evidence shows that copper has been extracted in the region for centuries. Indigenous people worked the copper deposits in pre-Hispanic times to make weapons and tools. The mine now produces 650,000 metric tons of copper annually.

Nouakchott was a small fishing village for hundreds of years. As recently as 1950, it had only about 200 residents. Drought throughout the 1970s brought migrants to the city, and its population swelled to about 150,000 in 1980. It now has just over 1 million people, and its urbanized area has changed from 5 km² in 1965 to 150 km² in 2016.

A 1965 close-up of Nouakchott from the Corona satellite shows the extent of the city at that time. Since then, the city’s expansion has been horizontal, spreading outward. Much of city’s urban growth occurs in informal settlements, which can be seen in the later Landsat images in the varying patterns of urban areas. Streets go in multiple directions and sprawl unevenly across the desert from the city’s center.

This may be against conventional wisdom, but this growing city in the desert is at high risk for flooding. The city is mostly below sea level and vulnerable to rising groundwater levels, seawater intrusions, porous soils, sand extractions, and heavy rains in low-lying areas.

In recent years, the number of rainy days has been increasing. The biggest problem is that a large amount of rain can fall in a short period of time. Since the groundwater level is high, and the type of soil there is not very good at absorbing even a small amount of rain water, rain cannot infiltrate into the ground. These factors lead to a city at high risk. In fact, heavy rains in August 2013 caused flooding in Nouakchott and south-central Mauritania.

A logging strategy that’s easy to spot in the Landsat imagery is clearcutting. All the trees in an area are harvested, and then replanting begins immediately. Replanting must be completed within 2 years of harvest. In Oregon, about 40 million new trees are planted each year. According to the Oregon Forest Resources Institute, the reforestation success rate is 95% on private land.

Clearcutting is a major change to the forest. Clearcuts look unattractive, and they disrupt wildlife habitat. The clearcut area can also increase streamflow in that area, and the soil can erode more quickly until reforestation occurs. Therefore, in Oregon, the size of clearcuts is limited to 120 acres. They are also limited further when near highways. Forested buffers must be maintained along streams, lakes, and wetlands. This protects against possible increased streamflow erosion and maintains wildlife habitat.

There are actually some positive effects to clearcuts. They create open space in the forest that many plants and animals need to flourish. The full sun promotes rapid regrowth of Douglas fir and other species that need full sun. Also, clearcuts are generally temporary. Oregon requires prompt reforestation.

What looks like lightning arcing through an ominous cloud is actually a dry landscape of rocky buttes in southern Utah and northeastern Arizona. Numerous rivers flow north from Arizona into the San Juan River. The light vertical feature at the top of the image is referred to as Comb Ridge, a jagged fold in the Earth's crust called a monocline.

This desolate landscape is part of the Sierra Madre Oriental mountain range, on the border between the Coahuila and Nuevo Leon provinces of Mexico.

Coastal inundation is an ongoing concern for the region near Semarang, Indonesia. This area faces several different types of flood risk, due to the potential combination of high tides, seasonal rainfall events, and river flooding. Much of this low-lying area is only 0–25 meters above sea level, and in some areas, land subsidence has also been occurring for many years. All of these factors lead to a risk of coastal flooding for local populations.

These Landsat images indicate changes in the area near Semarang City over the past 20 years. Semarang City is located at the bottom center of these images, and the differences along the coastline are particularly visible northeast of the city. In particular, the 2014 image shows coastal inundation that is encroaching on populated areas, roads, and structures.

Disaster managers and risk reduction personnel rely on satellite imagery such as Landsat to help document and mitigate flood threats as effectively as possible. The 42-year archive of Landsat imagery also provides a historical record that can be used to indicate long-term changes as they occur in coastal areas. This can help scientists and engineers understand and analyze historical trends, and assist with future planning for flood management and mitigation.

 

Landsat 8’s near-infrared and shortwave infrared imaging shows the pockmarked desert, perhaps more reminiscent of other planetary bodies than Earth. The age of the craters just about spans the entire Cold War. The first underground test was November 29, 1951; the last September 23, 1992.

Despite the hundreds of tests conducted throughout the Cold War years, only about 7% of the Nevada Test Site has been disturbed.

While nuclear explosions no longer rock the site, now called the Nevada National Security Site, nuclear weapons research still takes place there based on those tests. Computer simulations can help predict what happens during explosions.

The craters have also been used as Mars analog craters. Since access to the site is restricted, the craters are relatively undisturbed. That, along with the dry climate, helps scientists better understand craters on Mars, especially the types of craters that effectively expose near-surface material that Mars rovers and drones can study.

One of the most cratered landscapes on Earth is part of the Nevada Desert called Yucca Flat. Landsat 8's near-infrared and short wave infrared imaging shows the pockmarked surface perhaps more reminiscent of other planetary bodies than Earth.

The craters are relics from decades of nuclear tests conducted by the U.S. government since the early Cold War. An aerial photo from the USGS EROS archive shows that nuclear testing had already begun by 1952, but the largest crater had not yet appeared.

On July 6th, 1962 the Department of Energy detonated a 104 kiloton nuclear device as part of the Plowshare Program which explored the feasibility of non-combat uses of nuclear devices. The result was the Sedan Crater, shown in this declassified satellite image from 1965, and still visible in Landsat imagery today.

Find USGS aerial and declassified imagery at EarthExplorer.

Snow-capped Colima Volcano, the most active volcano in Mexico, rises abruptly from the surrounding landscape in the state of Jalisco. Colima is actually a melding of two volcanoes, the older Nevado de Colima to the north and the younger, historically active Volcan de Colima to the south. Legend has it that gods sit atop the volcano on thrones of fire and ice.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Denver, the capital of Colorado, is known as the “Mile High City.” The thirteenth step of the capitol building is exactly one mile (5,280 feet) above sea level.

On Earthshots we typically show “multispectral composites”—single-date images that combine three different wavelengths into one image. The example used in this section shows a different combination of infrared wavelengths than was used on the 2016 image from the “Interpret the Images” section. In this image, the clearcuts are pink against the bright green of the forest. This combination of infrared wavelengths makes the clearcuts that have occurred from one year to the next stand out more clearly.

We don’t often examine change over time in one image. That’s what the colorful image in this section shows. It’s a “multitemporal composite”—one image that shows three different dates combined. This image shows a combination of Landsat images from 1994, 2009, and 2016. Red shows clearcuts that were evident in the 1994 image. Green shows clearcuts that took place by 2009. And blue shows clearcuts that occurred by 2016. Darker tones are areas of forest that did not change in this time frame. This way of examining the imagery shows that logging has affected nearly the entire landscape shown, something that may not be evident when looking at a single-date image.

People derive many ecological and economic benefits from forests, and Landsat can help forest managers monitor changes to ensure these resources are available for future generations.

Some landscape changes around the world happen at glacial pace—very slowly—and have not been captured in the satellite era. However, glacial pace would not describe the changes to Alaska’s Columbia Glacier over the past few decades.

Columbia Glacier is a large tidewater glacier that flows south out of the Chugach Mountains in Alaska to Prince William Sound. Since 1980, its terminus has retreated 20 kilometers to make it one of the most rapidly changing glaciers in the world.

When it was surveyed by British explorers in 1794, Columbia’s terminus was at the northern edge of Heather Island. It stayed there until 1980, when its current rapid retreat began. A 300-meter deep fjord now replaces the portion of the valley once occupied by the glacier.

This series of Landsat images shows the rapid retreat, including an acceleration of the retreat in the early 1990s, followed by slowdowns in 1994–1997 and 2000–2006. It has picked up the pace of retreat again since 2006. Columbia has also become narrower, as shown by the expansion of bedrock areas in the images.

The false-color images use shortwave-infrared, near-infrared, and green wavelengths to highlight these changes, where snow and ice appear cyan, vegetation is green, open water is dark, and exposed bedrock is brown.

Why this matters

Land-based ice flowing into the ocean from tidewater glaciers is a leading cause of sea level rise. A 2015 study found that Columbia Glacier sent about 4 gigatons (billions of tons) of ice into the ocean every year from 1994 to 2013. An increasing rate of iceberg calving can also pose a danger to ships in shipping lanes.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Groton, Connecticut is home to the USS Nautilus, the first nuclear-powered ship and the first to reach the North Pole, a feat accomplished in 1958. The Nautilus is on display at the Submarine Force Museum.

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The satellite images presented on the Earthshots Web site are not intended to be used for scientific interpretation, only for educational purposes. Landsat data are freely available and may be downloaded from the USGS Global Visualization Viewer (GloVis) at http://glovis.usgs.gov or EarthExplorer at http://earthexplorer.usgs.gov.

Like scratches on a marble table, airplane contrails cut across the southern California Mojave Desert. The shadows from the contrails cast dark lines across the ground. Contrails form when cold, dry air mixes with warmer aircraft exhaust. Mountains and a few dry lakebeds provide a backdrop to this scene, along with bright green spots of agriculture along the Colorado River.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

The Landsat 5 image acquired before April 26 shows heated water being pumped from the plant into the adjacent cooling pond and circulating counterclockwise. Landsat 5’s thermal infrared band shows that heated water as orange, then gradually turning yellow then blue as it cools. But the image from April 29 indicates all the water in the pond is the same temperature, evidence the plant was not operating. As the first civilian satellite to image the disaster, Landsat 5 helped confirm the disaster had happened, and this was part of the evidence.

In just the past few years, the cooling pond by the former power plant began drying up. Satellite images clearly reveal a rapid decrease in water level.

Soon after the accident in 1986, radioactive material entered the pond from atmospheric fallout. The contamination went into the pond’s sediment and was shielded by the water. In 2014, the Ukraine stopped pumping water into the pond from the Pripyat River in order to save money. The consequence of this action could be to expose radioactive sediment to the air where it can be dispersed by the wind.

Often described as one of the world’s best cities to live, Copenhagen is growing steadily. That growth comes with challenges to keep it a desirable place to live.

In these false-color Landsat images, the urban areas of Copenhagen are shades of purple. Vegetation appears green, and farmland appears bright green when crops are growing and pink when the fields are fallow.

The Øresund Strait separates Copenhagen from Malmö, Sweden. The strait and other water bodies appear black.

In the time that these images span, the population of Copenhagen has grown from 478,615 in 1985 to 580,184 in 2015. But the population of greater Copenhagen in 2014 was 1,246,611, up from 1,084,885 in 2006.

The copper color in this infrared combination is the presence of lake ice in the Northwest Territories in northern Canada. The lake on the right side is Whitefish Lake, in a region with numerous glacial landforms. Bright wrinkle-like lines are eskers, ridges made of sand and gravel formed by glacial sediments deposited by meltwater rivers flowing on the ice. The blue color is land dominated by shrub tundra with some spruce stands.

To get an even more detailed view of this region, we can actually go back to satellite imagery from 1967. This pre-Landsat imagery, while black-and-white, helps to extend the record of land change on the Earth. These images are declassified reconnaissance satellite images and show detailed and informative views of the Seno Plain.

Comparing WorldView-2 with Corona shows the pattern of change that we see in Landsat, only in more detail. In the grayscale Corona imagery, bright areas are cultivated cropland. Dark gray is grass with shrubs and trees. In the natural color WorldView-2 images in 2011, much of that fallow or grassy land has converted to agriculture, indicated by light tan.

The resolution of the Corona image is 6 feet. For Landsat, it’s 30 meters. So in Corona, even single trees can be distinguished.

The more up close images show a few villages in higher detail and demonstrate that they have expanded with the growing population. The darker gray at the bottom of the 1967 image gives way to tan in 2011, which is intensive cropland. Those cattle corridors are also clearly visible in this WorldView-2 image.

October 16, 2018, marks the two-year anniversary of the Cottonwood Fire in western South Dakota. The fire consumed a large swath of grassland near the community of Wall and just north of Badlands National Park.

Thanks to low relative humidity, and high winds and temperatures, the fire spread quickly. It burned 41,360 acres by the time it was 100 percent contained two days later.

Imagery from Landsat and Sentinel-2 show the fire scar and relatively rapid recovery of the grassland in the two years since the fire. The Sentinel-2A image from October 31, 2016, shows the burn scar just 13 days after the fire was contained.

Recovery of a grassland fire happens more quickly than a forest fire. With enough moisture, grasses in fire-adapted landscapes use the postfire flush of nutrients to rapidly regrow. Only a very faint outline of the burn scar is visible in the 2017 Landsat 8 image. By 2018, the burn scar has disappeared.

Landsat and Sentinel have similar spatial resolutions and infrared imaging capabilities, allowing them to complement each other in burn severity monitoring.

Wildland fires can leave behind scorched mountainsides with no trees or other vegetation to stop rain-driven mudslides or dangerous debris flows. When such potential exists, the shortwave infrared (SWIR) and near-infrared (NIR) spectral bands of the Landsat satellite sensors help to identify those possibilities quickly.

The six images displayed show prefire conditions in 2014 and the progression of the Cougar Creek Fire in Washington on the eastern slopes of Mount Adams over the several days that it burned in 2015. Lightning started the fire on August 10, 2015, and it was not contained until mid-September. While it’s interesting to see the progression of the fire, it’s the prefire and postfire images that are really important for burn severity mapping.

(Black stripes run through the Landsat 7 images because of the Scan Line Corrector failure on Landsat 7 in May 2003.)

This image from the European Space Agency’s Sentinel-2A satellite offers a breathtaking view of Crater Lake National Park in southern Oregon. It offers something equally important to park managers, scientists, and anyone else interested in land cover change—a view that is highly similar and complementary to Landsat acquisitions.



In this 100th anniversary year of the National Park Service, land managers and scientists tasked with overseeing parks and other government-owned lands typically rely on frequent remote imaging to monitor changes to forests, vegetation, hydrology, and more. Frequent imagery means observers can detect change quicker, and address or manage the effects of change in a more timely fashion.



With its potential repeat coverage of every 10 days, Sentinel-2A should eventually provide additional revisit opportunities to the 8-day coverage from Landsats 7 and 8 combined. Sentinel-2A has spectral bands similar to Landsat 8, with a higher spatial resolution in several bands. So at Crater Lake, for example, a hydrologist seeking information on the amount of snow cover in the high country around the lake, and the subsequent snowmelt, should benefit in the future from more potential images.



Beyond scientific use, Sentinel-2A, like the Landsat satellites, offers a stunning view of the national park, which was established in 1902—14 years before the National Park Service came into being. Crater Lake formed 7,700 years ago when the volcano Mount Mazama erupted and collapsed into itself, creating the deepest lake in the United States. A burn scar visible just north of the lake in this image was caused by a wildfire in August 2015.



Sentinel-2A imagery is free and can be downloaded through EarthExplorer or GloVis, online search and order tools available through USGS.

 

Vegetation appears red in this piece, which moves from dark to light in the Atlas Mountains of Morocco. The vegetation grows along streams, which seem to follow a tortured course through the ridges and valleys before wandering through the desert.

These close-up images from Landsat show the Seno Plain in a bit more detail. The images were acquired during the dry season, so crops were not growing at the time. However, the images do show evidence of how intensely the land was being used for agriculture, indicated by the lighter toned patterns. As in the wider views, the Bandiagara escarpment is the feature on the left of these images.

The 1972 image shows that farmers practiced crop rotation, leaving some land fallow. The fallow fields are represented by dark patches. In 1986, however, much of the fallow is gone, and there is even less of it by 2016. Bright areas dominate the 2016 image, indicating wall-to-wall cropland over the plain. The darkest patches are grassy fallow areas and are either protected lands or used for cattle grazing.

Startling red patches sprout from an agricultural landscape that looks almost like a Cubist painting. The fields in this part of eastern Kazakhstan follow the contours of the land—long and narrow in mountain valleys, and large and rectangular over the plains.

The Cuesta del Viento (Wind Slope) Reservoir formed behind a large dam that was constructed on the Jáchal River in 1997–1998 in the San Juan Province of Argentina.



Surrounded by spectacular mountains, the reservoir controls the flow of streams from snowmelt of the Andes Mountains and provides a source of irrigation for fruit plantations and other crops. The reservoir has also become a popular destination for windsurfing and kitesurfing because of the consistent afternoon winds that reach 30–40 knots (55–74 km/hour; 34–46 mi/hour). These powerful winds are caused by the daily flow of air currents that travel out of the eastern Andes Mountains and converge in the river valley.

These Landsat images show the area in November 1996 (before the dam was built) and December 2013. The inclusion of Landsat’s shortwave infrared band information for this image pair also highlights the geologic features of the area.

Landsat images provide an unbiased view of features on the Earth’s surface and the changes that take place on the landscape.

These images show the Dallas–Fort Worth metropolis in northeastern Texas. This city has grown significantly in recent decades, from 2,378,000 in 1970 to 7,943,685 by 2022.

Dallas-Fort Worth International Airport, between Dallas and Fort Worth, opened the year of the first Landsat image shown here, 1974. A new runway added after 1974 can be seen west of the airport in the 1989 image. The north-south runway on the east side opened in 1996 and appears in images from 2000 and later. The airport covers almost 30 square miles, making it the second largest airport in the United States.

On August 4, 2014, an earthen dam failed at the Mount Polley Mine in central British Columbia, Canada. The dam had been built to hold a tailings pond that contained water and waste materials from local gold and copper mining operations.



The tailings pond covered over 4 square kilometers and within a few days, millions of cubic meters of wastewater and slurry had flowed from the pond into neighboring Polley Lake, Hazeltine Creek, and Quesnel Lake.



These two Landsat images show the area of active mining and associated tailings pond. In both images, the dark areas indicate clear water. The suspended materials within the tailings pond (first image) are more reflective, so this water appears brighter. In the August 6 image, the waste materials from the tailings pond can be seen (blue, green, and silver) flowing down Hazeltine Creek and into the two nearby lakes.

 

The western wall of Uzbekistan's Sardoba Reservoir breached on May 1, 2020 after a week of heavy rain. According to the news, thousands were evacuated as water rushed north into farmland and villages across the central Asian country and into neighboring Kazakhstan.

Imagery from Europe's Copernicus Sentinel-2 satellite shows water pooling across a wide area. In the May 4 image, three days after the breach, the reservoir appears partially drained. The water stored in the Sardoba Reservoir is used primarily for irrigation. This imagery indicates the extensive farmland in the region, largely cotton, a water-intensive crop.

Gypsy moth caterpillars devour the leaves of hardwood trees, causing the greatest damage in late June as the larvae reach maturity. The caterpillars are hungry little buggers, and they’re not picky eaters. Even though they prefer oak and aspen, they feed on other deciduous trees such as maple, birch, poplar, willow, apple, and hawthorn, and can go after coniferous trees during a large outbreak.

During a dense population boom, they eat all the leaves on a tree and can even defoliate entire stands of trees. Beginning in 2016, the combination of visible and infrared imaging from Landsat revealed the extent of the damage the outbreak has caused.

Healthy forest is bright green, but as the time series progresses, much of the green turns to faded brown as the infestation spreads.

Though gypsy moth outbreaks are a fairly regular occurrence in the more southern portion of their invaded range, this outbreak was the first time gypsy moths caused significant defoliation in New England since the 1980s.

How did they get here?

An amateur entomologist Etienne Léopold Trouvelot brought gypsy moth eggs from France to Massachusetts in 1869. He was conducting experiments with the eggs possibly to see if the gypsy moth could be an alternative to the native silkworm. The insects somehow escaped from his home and have affected the forests of the Northeastern United States ever since.

Visible in these images is one canal associated with the $62 billion South-North Water Transfer Project. Water resources are a concern in China because freshwater is distributed throughout the country unevenly. The south has abundant freshwater, but it’s scarce in the north. This project is an attempt to alleviate the water shortage in the north.

The entire project has three different canal routes that link China’s four major rivers (the Yangtze River, Yellow River, Huai River, and Hai River). The central route brings water from the Danjiangkou Reservoir north to Beijing. The reservoir was formed by the Danjiangkou Dam, completed in the 1970s. The height of the dam was increased from 162 to 176.7 meters above mean sea level between September 2005 and September 2013.

The Dasht-e Kevir, or Great Salt Desert, is the largest desert in Iran. It is a primarily uninhabited wasteland, composed of mud and salt marshes covered with crusts of salt that protect the meager moisture from completely evaporating.

The water surface level of the Dead Sea is the lowest natural land or water surface on Earth at more than 400 meters below sea level. That level continues to lower as water from Dead Sea tributaries is diverted for irrigation. In the southern part of the sea, the salt and potash industries use water from the sea in evaporation ponds. Water is not quickly replenished in this closed basin, so the level continues to drop.

The sea is made up of a northern basin and a southern basin. Both basins were once connected by a strait (see the 1973 image), but the strait is now dry.

(Black stripes run through some of the Landsat 7 images because its Scan Line Corrector failed in May 2003.)

Torrential rainfall swamped western Japan in July of 2018. The rain caused mudslides that flooded cities, damaged buildings and rattled the nation’s infrastructure. More than 170 people died.

These Landsat 8 images highlight the rush of muddy water that tore through the cities of Fukuyama and Kurashiki on its way to the ocean.

The waters of the Ashida and Takahashi Rivers appear light tan and gray in the first image, which was captured May 22.

The colors changed when the mudslides began. Each river becomes a thick, tan-colored snake of murky liquid on July 9, sending swirls of sediment into the sea.

The images are close to natural color. They were created using bands 4, 3, and 1 on Landsat 8’s Operational Land Imager. Band 1 is sensitive to suspended sediment in water.

Landsat data archived at the Earth Resources Observation and Science (EROS) Center can be used to monitor, study and respond to natural hazards worldwide.

This October, a system of storms caused significant flooding in most of Death Valley National Park, California. Collectively,  the area only received 1–2 inches (2.5–5 centimeters) of rain, but the annual average in Death Valley is about 2 inches  (5 centimeters). The largest of the storms occurred on October 18. Flash floods from the storm destroyed roads and utilities,  and damaged several historical structures. This was the largest flood event in the recorded history of the area. 

In this image pair Landsat 8 images contrast October 2014 (a year with typical precipitation) to October 2015. The false color images highlight hydrogeology; the areas in green to blue are the locations with moisture content. Especially striking is the Badwater Basin, normally a dry lake bed. In the 2015 image, it is full of water.

Landsat imagery acquired before and after the flood event will help with monitoring and evaluation of landscape response  and impacts.

A bit of blue cubism in southern Uzbekistan highlights the intensive irrigation that is common along rivers that flow into the Aral Sea. However, so much water is used for irrigation that very little actually reaches the Aral Sea. The perplexing variety of blue and green shades are farm fields with actively growing vegetation among the scattered residential zones.

Every year in Bolivia, a swath of forest two-thirds the size of Delaware is cleared of trees. Most of this deforestation has taken place in lowlands along and east of the Rio Grande River.

Compared to most Amazon soils, the alluvial soils in these lowlands are very fertile. The flat landscape is relatively easy to clear. And rain forests have an abundance of one obvious thing important to farming—rain. Besides that, the area is close to a large market and distribution center, the city of Santa Cruz, which lies just outside of these images, about 7 kilometers off to the southwest. One more benefit to the land owners: when farmland becomes too eroded or compacted for crops, farmers change to cattle production.

Until the 1970s, sugarcane was the major crop near Santa Cruz. By the 1980s, the price for soybeans increased. Today, sugarcane is still an important crop, but industrial soybean production has become the most common crop.

Different deforestation geometries reveal different types of agricultural management. Most noticeable might be the groups of long rectangles, which are large-scale agricultural operations. These areas require large capital investments, use heavy machinery to prepare the land, and involve intensive production of annual cash crops, mainly soybean, sugarcane, and rice. Dark strips within these fields are windbreaks, needed because the soils in the area are fine and prone to wind erosion.

Small-scale agriculture is indicated by smaller irregular plots. Small-scale farmers here produce mainly rice, maize, and perennial crops, such as bananas. The forest is cleared perpendicular to a road in long rectangles, forming a “piano key” pattern.

The radial-shaped patterns are planned settlements called nucleos. The individual farms radiate outward from a central hub, which is communal land. Most of these settlements are located in the large area of colonization visible in the northwest part of the main images, the San Julian area. There are a few others; see if you can find them in the later images.

All of Madagascar is being threatened by deforestation, but this threat is most apparent in the Spiny Thicket region. Spiny Thicket has a naturally slow rate of growth and regeneration, making it especially vulnerable to the effects of deforestation. The primary threats are from small-scale but widespread clearing of trees for firewood, agriculture, and livestock grazing. Human population growth increases the demand on natural resources. This is part of the reason for the increased rate of deforestation here. For example, more land is needed for agricultural production.

Landsat images show more clearly the extent of changes to the Spiny Thicket ecoregion in southwestern Madagascar. Over the past four decades, rapid deforestation has occurred on both sides of the Linta River. Most of these images are from around the end of the rainy season (October to April) when vegetation is near its peak annual growth.

The primary cause of this deforestation is conversion to cropland and pasture. But the reasons for this conversion are varied.

Countries that have extensive tracts of rain forest build roads into remote areas to improve transportation of goods. Legal and illegal logging follows the road expansion. Once an area is logged, it becomes a prime location for agricultural development, which further clears the surrounding forest. These cleared areas are also prone to wildfires, which can further degrade the forest.

Governments sometimes encourage the development of the rain forest with subsidies and tax breaks. Pressure from the global market for timber and soybeans drives the agricultural development.

People are drawn to delta and coastal regions, and about 7.7 million people live on the Ayeyarwady Delta. Deltas can be productive agricultural areas because the soil is rich and the flat terrain and water provide easy access to water-based transportation. The Ayeyarwady Delta produces 35% of Myanmar’s rice. Cutting wood for fuel also contributes to mangrove loss, but most of the deforestation in this delta has been for rice fields.

A more close-up look at the eastern portion of the delta shows this degradation in more detail. As the sequence of images progresses, the bright green of healthy mangrove changes into a mottled green of degraded mangrove.

This mangrove loss could have implications for protecting people on the delta. The delta’s low elevation and flat landscape make it vulnerable to flooding from storm surges, as with Cyclone Nargis in May 2008. The mangrove forests provide a buffer for storm surge.

The monarch migration is an endangered phenomenon. Logging in the overwintering sites in Mexico reduces the area available for the monarchs. The Monarch Butterfly Biosphere Reserve, established in 1986, is intended to protect the overwintering areas. But studies have shown that deforestation has occurred within the reserve. Some of that deforestation can be tracked from space with Landsat imagery.

According to Monarch Watch, during the 2012–2013 season, monarch colonies occupied the lowest number of hectares of forest in the previous 20 years. But the 2013–2014 season was even lower. Recent seasons have seen a slight increase in area of forest occupied, but monarch populations this low are extremely vulnerable. Just one winter storm could severely decrease their numbers.

Landsat sensors use infrared reflectance. One of the wavelengths of light they use is called near-infrared. Actively growing vegetation reflects this wavelength, so when this wavelength is assigned the visible color red, vegetation is displayed as red in these false color images. As you take a closer look at the zoomed in areas in the other sections, watch for gray patches in areas that were once red. This indicates a degraded forest.

Not all of the reduction in the monarch population can be attributed to oyamel forest loss in Mexico. In the United States, expansion of agriculture and herbicide use are reducing the milkweed that the caterpillars need. Extreme weather conditions have also been harming the monarchs. Satellite imagery continues to be useful in tracking the monarch population in these overwintering sites and can help recover this remarkable migration.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Delaware is known as the “First State,” because it was the first of the original thirteen colonies to ratify the United States Constitution.

Along the southern coast of the Netherlands, sediment-laden rivers have created a massive delta of islands and waterways in the gaps between coastal dunes. After unusually severe spring tides devastated this region in 1953, the Dutch built an elaborate system of dikes, canals, dams, bridges, and locks to hold back the North Sea.

The Huang He Delta has historically built up over a broad area because of its wandering ways. The river’s course in its lower reaches has shifted 11 times since 1855. The latest shift was in 1976. Before that, the river turned northward into the sea; in 1976, it took a different direction, heading east and carrying its sediment to build a new delta there.

The river now carries its sediment farther outward, creating an ever-changing delta.

The Wax Lake Outlet is a prominent north-south waterway. This artificial channel begins just upstream of Morgan City and carries water straight down to the Gulf. The U.S. Army Corps of Engineers dug the outlet in 1941 to prevent severe floods.

After the Wax Lake Outlet was created, water carried sediment to its mouth and began to build a delta, all of it underwater at first.

After flooding in 1973, caused by an unusually cold winter and above average spring rain, extra sediment rushed through the Wax Lake Outlet and, for the first time, its delta became visible. Reeds and willows began to grow and stabilize the new land. Their roots hold on to the sediment to keep the ground stable.

A little less than half of the Atchafalaya River flows through the Wax Lake Outlet. The rest also flows south to the Gulf a little to the east and is building a delta there.

The rest of the Louisiana coastline is retreating because Mississippi River water flows through narrow channels that don’t allow sediment to settle—the sediment-rich water speeds directly into the Gulf. The Atchafalaya carries sediment more slowly, which allows it to settle in the broad, shallow basin and maintain the marshes.

In the late 1960s, the Indonesian government began working toward improving and expanding its economy. It encouraged people to move to the remote and less developed eastern islands. One of the industries it expanded was logging. As workers cut down the primary forests, the forests were not allowed to grow back into secondary forest. Instead, they were planted as palm oil plantations. Palm oil trees are native to Africa and were found to thrive in Malaysia and Indonesia.

Palm oil demand is up as demand for biofuels rises. Biofuel producers say palm oil is a renewable alternative to fossil fuels. One hectare of a palm oil plantation can produce 10 times as much oil as other oilseed crops, including soybeans.

The palm oil plantations show up clearly in Landsat images in the middle of the undisturbed rain forest. Road networks—the pink jagged lines—cut through the green of the rain forest. One road leads from the cleared forest to the river town Asike.

The first cleared area that appears in these images covers about 14,500 hectares. By 2014, another new planted region appears just south of the first cleared area. The next section shows those cleared areas in more detail.

A marsh-like area borders the Demini River in northwestern Brazil. The Demini eventually joins the Amazon River.

Denver has all the classic marks of substantial urban growth over the past few decades. Satellite images reveal expanding residential areas, industrial zones, and new freeways that loop around the metropolitan area. Also visible is one of the largest airport building projects in U.S. history.

False color imaging from Landsat that combines shortwave infrared and near-infrared bands shows growth of the city. Bright green is vegetation, so parks and golf courses are the brightest green; dark green is the forested areas in the Rocky Mountains; and the more mottled green shades are the residential areas of the city. Purple hues represent streets, highways, and other mostly unvegetated infrastructure.

Denver is experiencing post-1950 growth similar to other western cities like Los Angeles, Phoenix, and Dallas. The Denver metropolitan area expanded in urbanized land from 150 square miles in 1950 to 499 square miles in 2000, primarily onto prairie and agricultural lands.

Seen through the "eyes" of a satellite sensor, ribbons of Saharan sand dunes seem to glow in sunset colors. These patterned stripes are part of Erg Chech, a desolate sand sea in southwestern Algeria, Africa, where the prevailing winds create an endlessly shifting collage of large, linear sand dunes. The term "erg" is derived from an Arabic word for a field of sand dunes.

Rock folding on a tectonic scale occurred in northwestern Africa. These motley ribbons dancing across the desert in Morocco are folds caused by the prolonged collision of tectonic plates. The long continuous line is Jbel Ouarkziz, a ridge that rises 200–300 meters above the valley floors.

In the American Southwest, transitions from one ecosystem to another can be dramatic and abrupt. This certainly is true in northern Arizona, USA, where the parched Painted Desert, shown here in a palette of purples, adjoins Sitgreaves National Forest (shades of green), a realm of pine woodlands with abundant wildlife. Within the Painted Desert lie the Hopi Buttes, a field of ancient volcanic cones, seen here as a scattering of dark, circular shapes near the top of the image.

The word desertification, if split into its roots, logically would mean the event of non-desert land becoming desert, but it is not quite so simple. Desertification is usually defined as a process that happens to land that is already normally arid (dry) or semiarid and it's not just caused by drought. In fact, the crucial factor is a decline in the biological productivity of the land—the amount of vegetation that grows (either naturally or that people have planted)—as well as the animal life supported by the plants. If desertification continues, eventually the land becomes a desert, with increased wind and water erosion, decreased soil fertility, and decreased water-retention capacity. Plant and animal communities decline in number and diversity, as many species can no longer survive.

Desertification is usually a patchy development, spreading outward from pockets of land where the vegetative cover has been harmed or destroyed, so that sandy dry soil begins to drift and vegetation is unable to reestablish itself.

In western Africa, boreholes (water wells) are often the points of this vegetation disturbance, because they attract livestock, which overgraze the land nearby. But in this example, the point of disturbance is a paved highway that was built to connect Nouakchott, the national capital of Mauritania, with the regional capital Rosso. Besides travel and transportation, the highway also encourages building and settlement. All of these activities consume vegetation for grazing, fuel, and building material. The vegetative cover becomes disturbed, some sandy soil begins to drift, and the process of desertification is underway.

In these images, the disturbances the highway causes become evident. The 1972 image shows the highway slicing across the desert's sand dunes. The other images show a widened corridor, the brighter tones that follow the highway.

Utah’s Green River flows south across the Tavaputs Plateau (top) before entering Desolation Canyon (center). The Canyon slices through the Roan and Book Cliff--two long, staircase-like escarpments. Nearly as deep as the Grand Canyon, Desolation Canyon is one of the largest unprotected wilderness areas in the American West.

Shuttle Radar Topography Mission (SRTM) data had previously only been available worldwide at 90-meter resolution. The National Geospatial-Intelligence Agency (NGA), NASA, and USGS are now releasing a newly processed, global SRTM 30-meter dataset.

The above images show an example of the difference between the 90-meter and 30-meter data of the Niger River Delta in western Africa. The Landsat image, also at 30-meter resolution, of the same area shows the extensive coastal estuaries, tidal flats, mangrove forests, and lowland rainforests of this part of southern Nigeria. More detailed elevation data are especially critical in such coastal settings that have small elevation changes.

For more information on the new SRTM elevation product, see the USGS Top Story here.

The building of roads and streets is a visible sign of urban expansion in Landsat images. Two new freeway interchanges show up in southwestern Sioux Falls in the 1995 and 1997 images. Once retail began expanding, new interchanges were needed to access the shopping and dining areas. After these new interchanges were built, additional development soon followed.

In new residential neighborhoods, the street patterns appear white-blue in color at first. These areas gradually change to a mottled blue-red as time goes on. Red indicates plant growth—in these neighborhoods, as trees mature, they begin to obscure the streets that were once clearly visible. As new residential areas expand west and south, you can see the new neighborhoods appear bright white-blue in color because trees are still too small to block the satellite’s view of the homes and streets.

A curious line appears in only the 2016 image, starting near the upper left, curving southeast, then bending straight east. This is the path of the Dakota Access Pipeline, which carries oil from the Bakken formation of North Dakota to Illinois. The line is not in the 2018 image as cropland or other vegetation regrew over it. The brightest part of the pipeline dig is on the west side of the image, near another bright spot, which is the regional landfill.

Devils Lake in northeastern North Dakota is a closed basin lake. Located at the lowest point within its basin, Devils Lake has no outlet. The result is that the lake is more prone to significant lake level variations. Lately, it has only been rising.

A USGS North Dakota Water Science Center graph shows the lake’s level has been higher in the past two decades than ever recorded.

The frozen tundra of northern Canada might not be the first place you’d look for a diamond mine. Diamonds are created under intense heat and pressure, yet here they are being mined in a cold, icy region.

These mines are located about 320 kilometers (200 miles) northeast of Yellowknife and just 200 kilometers (124 miles) south of the Arctic Circle. The tundra here consists of boulder fields, wetlands, and over 8,000 lakes with interconnecting streams. The lakes are visible in the images as the numerous dark shapes.

The two diamond mines visible in these images are Ekati and Diavik, both located in Northwest Territories, Canada. Ekati is in the northern part of the images. Diavik is in the southern portion and extends into the lake in the series of images.

Most of the year, these mines are accessible only by air. An ice road is open for about 10 weeks of the year during winter. No other roads reach the mines.

Production in the Diavik Mine began in January 2003. By 2013, Diavik had produced 84 million carats.

In this time series, you will notice something different about the mine pits of Diavik. The diamond ore is under the lake, so the pits were built in the lake. To protect the water of Lac de Gras, a dike was built before digging the pit.

Construction is a challenge in this remote location with a short construction season. The dikes had to be completed when the lake was not frozen—only about a 4-month period. The first dike was made watertight in 2002 and was pumped dry 3 months later. Silty water was cleaned before being sent back to the lake. A smaller dike was completed in 2006. The dikes allow safe mining in the open pits.

In September 2012, Diavik transitioned from an open-pit mine to an underground mine. More engineering and construction feats were needed for this change. Ventilation systems, pump stations, 12 miles of tunnels, vertical tunnels for ventilation and water removal, and other rooms make the underground mining possible. Diavik is expected to operate through 2023.

Diavik has a private airstrip of its own. The 1,600-meter (1-mile) long runway can accommodate Boeing 737s. It’s visible in the images as the straight line north of the mining operations.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

The Dixie Fire has become the largest single fire in California's recorded history. State fire officials don't list it at the top, however. The record is held by the massive August Complex Fire of 2020 which burned over one million acres. The term "complex" is used when multiple fires in the same area ignite separately. Designating the fires as a complex allows them to be managed under a unified command.

The Dixie Fire ignited on July 13th, 2021 near Cresta Dam in the Feather River Canyon. Nine days later the Fly Fire started 3.5 miles north of Quincy eventually merging into the much larger Dixie Fire. Hot weather and strong winds spread the blaze across national forests and into Lassen Volcanic National Park.

These near-infrared and shortwave infrared images cut through smoke to highlight burned areas, while natural color versions of these scenes expose the massive amounts of smoke generated.

Doha, the capital of Qatar, used to be a small fishing and pearl diving village. It’s now Qatar’s largest city with skyscrapers and a fast-growing urban area. Doha is investing heavily in education, culture, and sports. The vast majority of Qatar’s population lives in metropolitan Doha.

Oil was discovered in Qatar in 1937, and development began after World War II. Modern urbanization soon followed, and the country now has the highest per capita income in the world.

After winning the bid to host the 2022 FIFA World Cup, Doha had a new motivation to develop its infrastructure. The Qatar government invested in new stadiums and improved public transportation systems.

The urban growth in the PRD is vast. There are no longer any clear urban centers—a different growth trajectory from other large cities in China such as Beijing and Shanghai that have grown around defined historical urban centers.

Buildings and paved surfaces replaced vegetation at a rapid pace over the past three decades. Housing, factories, and the highway system all increased mostly at the expense of farmland.

In the early images of this series, cities are pink areas, separate from one another, among the green forested and agricultural areas. The largest city in this set of images is Dongguan. A noticeable change by the 1994 image is a road network beginning to connect those cities. The urban area soon begins filling in the former agricultural areas and surrounds the hilly forested areas.

In the southern part of the images, blue rectangles are aquaculture, and they are gradually pushed toward the coast by the expanding urban areas.

The city of Dongying is prominent in the 2010 image. Its current population is over 1.2 million. But you won’t find the city in the 1976 or 1979 images because it isn’t there. Dongying was established in 1983 with the opening of an oilfield on the northern delta.

Also noticeable in the time series images is the expansion of salt and shrimp farms, displayed by the dark geometric shapes along the coast. These farms were built on what were once tidal flats, a muddy coast that served as a buffer against storm erosion. Extensive development has degraded the tidal flats, resulting in increased coastal erosion.

The aquaculture development on the delta can have positive effects. While many of the shapes seen in the images are salt fields, many are shrimp farms that have recently moved toward culturing different seafood such as sea cucumber and crabs. These species have a lower carbon footprint, and shellfish also help clean the coastal waters. Another species beginning to be farmed is algae, which are at the very bottom of the food chain. Algae, often used as a nutritional supplement, are great at sequestering carbon dioxide from the atmosphere.

The rapid population growth in this area puts pressure on water resources and on the land, which has to grow increasing amounts of food. The region will need to plan carefully for the growth that accompanies economic development.

Nicknamed "Dragon Lake," this body of water is formed by the Bratskove Reservoir, built along the Angara River in southern Siberia, near the city of Bratsk. This image was acquired in winter, when the lake is frozen.

After several consecutive years of below-normal precipitation, the U.S. state of California is preparing for its most severe drought emergency in decades. The current drought is due in part to decreased rainfall along with reduced winter snowpack in the Sierra Nevada mountain range. In 2013, California received less precipitation than any other year since it became a state in 1850. Water conservation efforts are already in place for many locations. For 2014, there is potential for major agricultural impacts, and the wildfire danger is expected to be unusually high.

These three images show a portion of California’s Central Valley (left side of the images) and the neighboring Sierra Nevada mountains as viewed by Landsat in February 2011, 2013, and 2014.

The decrease of winter snow cover can be seen in this progression of images. The reduction of available water supplies in the Central Valley is also indicated by the changing outlines of Folsom Lake, Camanche Reservoir, and other lakes and reservoirs in the images.

The 40-year archive of Landsat imagery is useful for monitoring the changing conditions of Earth’s surface areas through time.

The Amazon Rainforest in South America typically experiences its drier season between the months of July and October. Satellite imagery from Landsats 9 and 8 show severe drought conditions in 2023 in comparison to 2022 when the area received average rainfall.  Landsat satellites capture images of the withering watershed of the Rio Negro, the largest tributary of the Amazon River, every 8 days.

A prolonged dry spell has sparked woes over water availability and wildfire in the western United States. This stretch of northern California is heavily reliant on man-made reservoirs. The recent history of a single Landsat scene can serve to illustrate the ripple effects of those severely parched conditions. Water levels have dropped in Folsom Lake, Indian Valley Reservoir, Black Butte Lake, where many fields have been left fallow, and Lake Oroville, which is home to the tallest dam in the United States at 770 feet. Each reservoir across this scene's 114 square miles has a wider shoreline today than it did in 2017, the last year with significant precipitation, most of which arrives in the winter and spring each year. Precipitation is more than 8 inches below normal for 2021, a rough start after a 2020 that ended more than 13 inches less than normal. The 2021 imagery shows evidence of another dry weather worry: large wildfires. The Bear Fire left a charred landscape in the fall of 2020, and scars surround a depleted Lake Berryessa.

About 5 million tourists visit Dubai every year and they have plenty to see and do. To attract tourists, Dubai developed the world’s fastest roller coaster, the world’s tallest building, and the world’s largest shopping mall. It also built fancy hotels, beaches, and even a huge indoor ski resort.

In the first image of this series, desert fills much of the image. As Dubai expands, roads, buildings, and irrigated fields spread out over the desert. But the most prominent project in Dubai, and an impressive engineering feat, is the artificial islands built off its coast. The islands were built from sand dredged from the sea floor. Rock breakwaters protect them from erosion. These Landsat images show the rapid and impressive development of these islands.

The United Arab Emirates (UAE) holds about 6% of the world’s total oil reserves. The oil cannot last forever, so Dubai is thinking of the future. The fast-growing city, and most populous in the UAE, is diversifying its economic base by becoming a luxury tourist destination.

Landsat can track the city’s urban growth, along with numerous other types of landscape changes.

(Black stripes run through some of the images because of the Scan Line Corrector failure on Landsat 7 in May 2003.)

At the southern end of Bahrain is a sight that can only really be appreciated from far above. The first residents moved to this group of artificial islands in 2009. Designed for residential living and tourism, the complex includes six atoll-like islands that surround five fish-shaped islands.

These images reveal additional projects that are in progress throughout the region. The Crescent is the center and will be a commercial hub, with apartments, offices, restaurants, shopping, and a 600-room hotel. The Durrat Marina is under construction to the north and will provide space for 400 boats and yachts. A planned golf course will be built amid 2,220 luxury residential villas and apartments and take up about 90 hectares.

When completed, the Durrat Al Bahrain will be able to accommodate 60,000 residents. Construction of the islands can be seen in the 2003 Landsat image. Many of the atolls have been developed. Look carefully at the 2014 and 2015 images. In just a matter of months, development began on the two southernmost fish-shaped islands. A 2023 image shows a more current view.

(Black stripes run through the 2006 images because of the Scan Line Corrector failure on Landsat 7 in May 2003.)

Even with these reservoirs, dry lakebeds surrounding Zabol are problematic. A “120-day wind” blows in this region. These persistent spring and summer winds can cause dust storms in and around Zabol.

Zabol reports dozens of dust storms every year. Clouds of dust from the lakebed cause breathing problems and can spread respiratory diseases. Many villages in the region have been abandoned.

The August 2000 image shows an extensive dust storm blowing sediment off the dry lakebed toward the south. The dust plumes obscure most land features and reach to Lake Gowd-e Zareh and beyond.

The view of this region from Landsat is so fascinating, it’s the subject of two Earth As Art images. These and all Earth As Art images can be downloaded for free from the EROS Image Gallery.

Eerie Cloud Shadows

Geometric Desert

The tendency to recognize human faces in things that are not human is common. Can you see the eye, nose, and mouth in this satellite image of Morocco? The face captured in this "Earth Selfie" appears to be quietly watching over the waters just off its coast. The city of Agadir is underneath the chin, and the irrigated farms of the Souss Valley appear in red.

The US Geological Survey's Earth Resources Observation and Science Center, or "EROS" archive’s data from the Landsat satellites which have been in operation from 1972 to the present day. EarthShots presents environmental changes using Landsat images.

Fresh lava flows from the 2018 eruption of the Kilauea volcano in Hawaii.

Flooding caused by the category 3 Hurricane Katrina in New Orleans, LA.

Center-pivot irrigation systems near Garden City, Kansas. Red indicates growing crops.

Urban expansion in China's largest city.

Farm fields become grasslands in the years after the nuclear accident in Chernobyl.

Evaporation ponds on the southern dead sea.

An open-pit copper mine in the Atacama desert.

The Filchner Ice Shelf in Antarctica breaks up over time into large icebergs.

Urban growth in the Dallas-Fort Worth metropolitan area.

Healthy crops are red, and gray shows where hail wiped out cropland in the Sioux Falls, South Dakota area.

Rainy weather in the 1980s brought the Great Salt Lake to high water levels.

Shrimp farming on the coast of Central America

The sediment-laden Yellow River forms a beak-shaped delta.

A glacier blocks a fjord to form a temporary lake.

Here we can see deforestation along with the formation of a large reservoir.

Visible changes to the layout of farmland in the Netherlands.

Different intensity of irrigated farmland on the US-Mexico border.

Land reclaimed for agriculture behind a sea wall.

Changing water levels in a Caspian Sea lagoon.

Glaciers on Mount Kilimanjaro can be seen shrinking over time.

The changing delta of the Omo River Kenya.

Shifting locations of coal mines and reclaimed land in Ohio.

Agriculture shown in red expanding from the banks of The Nile River across the tan colored desert

Miles of rain forest in Brazil cleared for farming and grazing.

Chile's expanding capitol city, with agriculture shown in bright red.

New land adds to the island nation of Singapore.

The path of a tornado is clearly visible through a small town.

Large swaths of Bolivian rain forest are converted to agriculture.

Expansion of Australia's largest city.

Burn scars from annual fires in the Australian bush

A rapidly retreating glacier along the Alaskan coast.

Expanding open-pit diamond mines in northern Canada.

Artificial Islands built off the Dubai Coast.

Lake Chad in west Africa shrinks as green wetlands replace open water.

Changing water levels in a closed basin lake, in Iran.

Urban growth in Las Vegas, one of the fastest growing metro areas in the US.

The 1980 eruption of St. Helens destroyed 150 square miles of forest.

Palm oil plantations in the middle of undisturbed rain forest.

Expanding phosphate mines in Florida and green reclaimed land.

An expanding capitol city in the desert of Saudi Arabia.

Evaporation ponds in a salt flat in the Chilean Desert

Suburban expansion, pushing beyond the outer loop highways of San Antonio.

Agricultural expansion using center-pivot irrigation systems in the Arabian desert.

Lakes formed in the desert from water diverted from the Nile river, are then diminished over time.

Fire scars from the 1988 wildfires in Yellowstone National Park.

The shrinking of the Aral Sea, once the 4th largest lake in the world.

Africa's tallest dam, and a large reservoir behind it.

These green and blue swirls in the Bering Sea reveal the bottom of the food chain in the ocean. Microscopic organisms called phytoplankton, which are important to fish populations, may be too small to be seen individually, but in vast numbers they are visible from space. The white clouds in the image look like bubbles in an aquarium.

Eastern Asia is dominated geographically by China, which stretches from the Tian Shan Mountains in the west to the sheltered bays of the Yellow Sea in the east.

On the east side of Sioux Falls, cropland continues to give way to developed land. Many U.S. cities have grown with a similar pattern—people moving to suburbs instead of to the central part of cities. Suburbs changed from bedroom communities to having their own focal points for retail and service industries. Sioux Falls reflects this phenomenon at a smaller scale—both retail and residential development expand into these suburban-type areas.

Note that the land is cleared first, noticeable as a pale smudge, and then street patterns emerge. Larger white blocks in the images are retail establishments, often with parking lots surrounding them.

Retail development covers former farmland along a new highway called Veterans Parkway. The road eventually lengthens to meet up with Interstate 90 to the north, a strong hint at where more growth is planned.

Northeast of this Sioux Falls expansion is the city of Brandon. There is starting to be less distance between Sioux Falls and Brandon. Since 1970, Brandon’s population has grown by over 500%, greatly outpacing the Sioux Falls metro population rate of growth during this time.

The Edrengiyn Nuruu forms a transition zone between the Mongolian steppes to the north and the arid deserts of northern China to the south.

Just west of Clay City, there is a large, nearly square-shaped area of floodwater in the 2008 flood image. It covers about 2,200 acres. The fact that this area became inundated indicates that it is low lying land. It’s possible that during the flood, water flowed from the nearby Eel River through a breach. The 2007 image shows this area as cropland, which is commonly low and flat. Roads, built up above ground level, could be causing the straight lines that appear around the water in the flood image.

Interestingly, this spot was once an artificial reservoir, called the Splunge Creek Reservoir, that formed in the 1800s to supply water to the Wabash-Erie Canal, which no longer exists.

These cloud patterns cast eerie shadows on the landscape of southern Egypt. The clouds appear red and the desert below hazy blue in this infrared rendition.

In mid-January 2014, unusually heavy rains in southeast France led to flooding, landslides, and evacuations. In some areas, up to 20 centimeters (8 inches) of rainfall occurred over three days, far exceeding the typical monthly totals.

These Landsat 8 images show the area around Hyères, along with the Giens Peninsula (Presqu’île de Giens) and nearby islands.

The two images were acquired on January 15, 2014 (one day before the rains began) and again on January 31, 2014. The bright blue colors in the right image show the flow of the sediment-rich floodwaters as they moved out into the Mediterranean Sea.

Ekati is Canada’s first diamond mine. Diamond ore bodies are called kimberlite pipes. These carrot-shaped pipes are the roots of ancient small volcanoes. Diamond-bearing kimberlite was discovered at Ekati in 1991.

Construction of the mine started in 1997 and it officially opened in October 1998. By 2011, the Ekati mine had produced 50 million carats of diamonds.

Ekati is the name the Tlicho people gave this area. It means “fat lake,” a reference to white quartz in the rock on the shore of Lac de Gras. The quartz looks like marbled caribou fat. Lac de Gras is the large lake south of the mines.

You can see the mining operations expanding in this series of images. The Ekati mine includes open-pit mines in different locations. In the lower right is the Misery pit. It’s connected to the main base of operations by a road, visible as the curving pink or white line.

Ekati has its own airport that’s used year-round. That’s how employees get there. The runway is visible as a straight line just south of where the first open pits begin appearing.

The company that runs the Ekati mine, Dominion Diamond Ekati Corporation, monitors the air, water, and wildlife in the area. They are already planning ahead for the eventual closure of the mine and land reclamation.

These images show the vicinity of the Elburz Mountains in northern Iran. Tehran lies in the south, and the Caspian Sea is to the north.

The Elburz Mountains run parallel to the southern coast of the Caspian Sea, and these mountains act as a barrier to rain clouds moving southward; as the clouds rise in altitude to cross the mountains they drop their moisture. This abundant rainfall supports a heavy rainforest (the bright red area) on the northern slopes. The valley to the south receives little precipitation because of this rain-shadow effect of the mountains.

In September 2011, the largest dam removal project in U.S. history began.

Two dams built on the Elwha River in the early 1900s created two reservoirs in northwestern Washington. They also greatly reduced the amount of sediment flowing to the river’s delta and blocked salmon migration upstream into Olympic National Park.

A 2011 image from Landsat 5 shows the river before the dams were removed. The Lake Mills and Lake Aldwell reservoirs are visible along the river. After dam removal, images from Landsat 8 using shortwave infrared and near-infrared imaging reveal sediment blanketing the beds of the former lakes. Closer views show the river changing course over time.

With the dams gone, the river deposits more sediment at the delta. Natural color images show sediment flowing into the ocean.

A USGS animation shows the changing Elwha River delta. The animation is based on shaded relief elevation maps from summer topographic and bathymetric surveys.

USGS scientists continue to monitor the river with aerial photos.

White pinpricks of cloud cast ebony shadows on the Rub' al Khali, or Empty Quarter, near the border between Saudi Arabia and Yemen. The lines of wind-sculpted sand are characteristic of immense sand deserts, or sand seas, and the Rub' al Khali is the largest desert of this type in the world. A highland ridge is just high enough to disturb the flow of the lines. In the center of that interruption lies the Saudi Arabian town of Sharurah.

Meanwhile, at the summit of Kīlauea, the Halema‘uma‘u crater and surrounding caldera floor subsided throughout the summer of 2018. Kīlauea has something like a plumbing system connecting Halema‘uma‘u crater at the summit to the lower flanks of the volcano. The collapse at Halema‘uma‘u suggests the underlying magma reservoir largely drained into the lower East Rift Zone to feed the lava flows.

Magma draining from the summit hints at the possibility of a quiet interlude at Kīlauea for several years. While April 30, 2018, marked the beginning of the recent lava flow event, it also marked the end of the continuous eruptive activity at Pu‘u ‘Ō‘ō that started in 1983.

Although lava flowed from the East Rift Zone and devastated the Leilani Estates neighborhood, the April 30 collapse of Pu‘u ‘Ō‘ō crater left this eruption site devoid of lava. Since lava did not return to the crater after August 4, the USGS has said the Pu‘u ‘Ō‘ō eruption is over.

However, the USGS Volcano Hazards Program says Kīlauea is still active and will erupt again. Volcano hazards in the area remain the same. Based on historical data, it’s unlikely that lava will erupt again from Pu‘u ‘Ō‘ō, but the East Rift Zone still has magma underneath, and it will erupt again through another vent. It may take several years for enough magma to accumulate again, but Kīlauea and the East Rift Zone remain very active.

The USGS Hawaiian Volcano Observatory created a geonarrative to summarize the history of Kilauea eruptions and the 2018 lava flows.

The environmental implications of the shrimp farm expansion are potentially far-reaching.

• Fish meal fed to the shrimp can contaminate the environment
• Antibiotics used on the shrimp are associated with human health problems
• Misuse of antibiotics and other chemicals can affect groundwater quality
• Mangrove forests are lost

The loss of the mangrove forests leads to further problems.

• Increased risk of inland flooding
• Degraded water quality can reduce catches by off-shore commercial fishers
• A carbon sink area can become a carbon source

Images from Europe's Copernicus Sentinel-2 satellites show a bit more detail than Landsat. These close-up views of Shiyan show the industrial development and land clearing at 10-meter resolution. Blue-topped rooftops are buildings for industry; light tan spots are leveled land.

The hills that are being flattened vary in height from 100 to 150 meters. The material used to level the hills is used to fill valleys. However, building on this infill might not be best for urban construction. The soft soil from the infill subsides easily and is prone to landslides.

Other environmental problems are cropping up based on this land leveling. The process of moving this much material throws dust particles into the air. Changing hills to plains has caused soil erosion, which adds sediment to local water sources. Shiyan is near the headwaters of the South-North Water Transfer Project, a huge project that diverts water to northern China. The sediments can end up in waterways, polluting the water. Furthermore, it can take years for the flattened ground base to be stable enough for building.

The dark heart in this vivid African landscape is the Erongo Massif, an isolated, sheer-walled mountain that rises 1,200 meters (3,937 feet) above arid Namibian plains. The massif is a remnant of a gigantic volcano that was active roughly 150 million years ago. At some point, the volcano's center collapsed in upon itself under the weight of overlying lava. Eons of erosion by wind and wind-blown sand gradually exposed the long-dead volcano's core of granite and basalt.

After the eruption, many areas near the volcano were stripped of vegetation. The series of images reveals the regrowth of vegetation, but it progressed at different rates. The eastern side recovered the fastest, where the area was mainly affected by falling ash. Wind and rain removed the ash, and most areas on this eastern side recovered to almost pre-eruption levels in about 7 years.

The mountain’s western side experienced the worst of the pyroclastic flows, causing regrowth to be slower and more variable. In fact, some areas are still bare.

A remarkable feature of the series of images, even in the most recent images, is that mudflows can still be seen trailing away from the mountain’s summit more than 30 years after the eruption. Runoff from monsoon rains and typhoons continued to erode and redistribute the pyroclastic deposits years after the 1991 eruption.

Another change visible at this scale is the summit itself. The eruption caused the summit to collapse into a caldera about 2.5 kilometers wide. Water has collected in the crater to form a small lake.

Landsat’s infrared bands set up a clear contrast between vegetation and lahar deposits. The images make it clear that the lahar hazards continued, and many occurred in inaccessible areas. Vegetation shows up as bright green, while the sediment and bare ground from lahars is pink. It also shows the progression of the revegetated areas on the mountain’s slopes.

This progression is aided by additional scenes from Terra’s ASTER sensor. ASTER uses similar infrared bands to Landsat, and its 15-meter resolution reveals slightly more detail than Landsat’s 30-meter resolution.

Isolated in Chile’s northern Atacama Desert, the open-pit Escondida Mine is the world’s largest source of copper.

Escondida means “hidden” in Spanish, and hidden it was. The copper ore was buried under hundreds of meters of rock. The only way it was found was by drilling along a line of other known copper finds that stretched hundreds of kilometers.

Copper represents a substantial part of Chile’s economy. In 2013, copper mine production was valued at just over $30 billion. Chile is the world’s leading producer of copper, accounting for nearly 32% of world copper production.

With these water use maps, land managers and farmers can tell which crops use the most, or least, water at the field scale. From this, they can determine whether water could be used more efficiently. At the basin scale, large-area maps can be used to evaluate aquifer depletion and quantify groundwater pumping; or resolve water rights allocation disputes.

The accompanying pair of seasonal ET maps (May–September) shows crop water use in the San Joaquin Valley in 1990 and in 2014. The colors correspond to millimeters of water returned to the atmosphere through ET. Fields that are green and blue show the highest ET values. Relatively more water has been used on those irrigated fields. Orange hues are areas that have very little ET, such as sparsely vegetated desert.

Comparing the maps reveals changes in irrigation patterns during this period. Notice, for example, that water use intensified in many places (increase in blue areas) and some irrigated lands (green in 1990) transitioned out of agricultural production (reddish brown) by 2014.

These water use maps can show not just seasonal ET but water used in a single day, or even over the course of decades thanks to the extensive Landsat archive. View the .gif animation below that shows an annual ET map for every year from 1984 to 2014. This map series shows flooding events around Tulare Lake Bed in 1984 and 1997.

Accurate information on water availability and usage is necessary for planning sustainable use of water, particularly in an arid region like the southwestern United States. The study done for the San Joaquin Valley can become the basis for planning, monitoring, and assessing water use across the country. These maps can help farmers and land managers optimize and conserve water resources.

Is this a black-and-white image? No, this is a natural color image of snow-covered southwestern Russia. Windbreaks, roads, and fence lines look like random pencil marks near the Volga River, which flows across the top of the image. The thick lines are trees planted to protect fields from dry wind and erosion; these windbreaks retain snow, allowing more moisture to penetrate into the soil.

Europe is a modestly sized continent, only Australia is smaller, but its long, irregular coastline is riddled with bays, inlets, islands, and peninsulas, both great and small.

A large infrastructure project has changed the shape of the coastline of the Netherlands while increasing the cargo capacity at Europe’s largest port. This pair of Landsat images spanning 15 years shows the Maasvlakte 2 project, which is an expansion of the Port of Rotterdam. The port provides accessibility for the transportation of cargo from Rotterdam to the rest of Europe.



Land building at Maasvlakte 2 began in 2008. About 230 million cubic meters of sand were dredged from the North Sea to create about 5,000 acres of new land. In addition, 7 million metric tons of stone were used to construct new seawalls.



Commercial cargo operations at the new Maasvlakte 2 facility began in December 2014. Its terminals currently can hold 2.7 million individual 20-foot shipping containers. There is more space for terminals to be built on the new land once demand increases, which would increase the port’s cargo handling capacity even more.



The expansion of land resulted in some loss of permanently flooded sandbanks that affected the availability of food for some protected bird species, such as the common scoter, the sandwich tern, and the common tern. However, this loss was compensated for by establishing a protected seabed area south of the Maasvlakte 2 in the Voordelta. Also, three bird resting areas in the seabed were established where boat traffic is restricted. Landsat can help monitor this coast to ensure the positive impact of these protected areas as compensation for the land expansion.

The Suez Canal is a man-made waterway connecting the Mediterranean Sea and the Red Sea. It is one of the world's most important waterways for trade, but the main channel was previously too narrow to allow ships to travel and pass in opposite directions.

A massive expansion project was started in 2014 to increase the depth of the existing channels and create a separate shipping lane along a major portion of the Suez Canal. The project took one year to complete and included 22 miles (35 kilometers) of new channel near Ismailia, Egypt. This new shipping lane will dramatically shorten the travel times for ships traveling in both directions.

This series of Landsat 8 images shows the area before, during, and after construction. The first image (August 2014) shows the Suez Canal near the time construction began. The new route is faintly visible in the second image (December 2014) while construction was in progress. The third image (August 2015) shows the completed and operational canal project, with the new shipping lane filled with water and clearly visible.

The 40+ year archive of Landsat imagery is a valuable resource for monitoring land use changes over time.

 

In a remote part of the Western Desert in central Egypt, highly eroded plateaus rise from the desert floor. The bright speckles are ancient dry lakes, the salt deposits reflecting brightly. Long ago, water flowed off the plateau, forming the breaches seen on the plateaus’ edges. This desolate land between oases is surrounded by extensive sand dunes.

Lake Manicouagan, Canada, is one of the Earth's largest and oldest known impact craters. The crater is 65 kilometers (40 miles) wide and is estimated to be about 214 million years old. The lake and island are clearly seen from space and are sometimes called the "Eye of Quebec."

Near the western edge of the Sahara Desert is a feature that resembles a large eye when viewed from space. The Eye of the Sahara, also known as the Richat Structure or Guelb er Richat, is a symmetrical dome of eroded sedimentary and volcanic rock. The outermost rings measure approximately 40 km (25 miles) across. Persistent northeasterly winds keep much of the dome free from sand, exposing the various layers of rock. The circular feature was initially interpreted to be an asteroid impact structure, but most scientists have now concluded that it was caused by geologic uplift.

This Landsat mosaic of four different scenes shows the geologic feature in false color. By blending visible and infrared wavelengths (bands), scientists can enhance the visibility of the various rock layers in contrast to the surrounding sand (yellow to white).

The Eye of the Sahara is featured along with many other selected images in the USGS Earth as Art series: https://eros.usgs.gov/imagegallery.

Rupert Bay, an arm of James Bay, extends into Quebec, Canada. Many rivers carry sediment into the bay and combine with seawater coming in from the tide. A prominent sediment stream extends past Stag Island and a vortex curls off Stag Rock in the middle of the bay. Sediment trails off the islands toward the mainland, indicating the tide was coming in at the time of image acquisition.

Fluorescent colors dominate this dreamlike scene. The orange shapes look like glowfish in a fanciful underwater world. Those glowfish are actually clouds, and the neon green represents mountains, including Mount Rainier, near Seattle, Washington.

One new building project that exemplifies some of these trends is visible southeast of Beijing. Fangzhuang is a new city of 78,000 where in 1984 only 1,000 people lived in agricultural villages just outside the Outer City. In the 1977 image, agriculture, represented by red, dominates the area. By 2022, those lands have been swallowed up by development.

Fangzhuang includes condominiums, 3-story apartment buildings, schools, parks, shops, and a community center. Such prestigious work-units as the Ministry of Foreign Affairs have bought blocks of apartments, and since 1994 some foreigners have moved in. Operations such as health care, day care, and garbage collection are still managed by socialist-style committees of residents.

Water from the Balkh River fans out into an agricultural area toward an arid region in northern Afghanistan, near the border with Uzbekistan and Turkmenistan. Part of an ancient region called Bactria, extensive irrigation produces melons, almonds, apricots, and grains. Mazar-e Sharif is the urban area that dominates the lower right corner of the image.

The aerial photo from 1952 is black and white and doesn’t have the infrared imaging capability of Landsat, but it has something that Landsat doesn’t—very high resolution.

It’s possible to locate trees and buildings in this image. Zooming in to an area near the lake is a location that is cultivated cropland. The sharp corners mark the different fields.

Land here is divided into sections of 1 square mile. These extreme closeups show an area of land covering approximately six sections. This area shows three sections across and two sections high.

A closer look shows farm buildings, with a shelterbelt of trees beside them.

Later Landsat images reveal that those fields and structures are underwater.

* = Location of farm structures shown in the aerial photo closeup.

When landmasses collide, rock layers can break. Geologists call these breaks "faults." Rock layers are offset in this image in western China, making the faults remarkably clear. The different colors indicate rocks that formed at different times and in different environments.

The smell of a fresh cut Christmas tree can evoke visions of majestic evergreen forests teeming with winter wildlife.

In truth, more than half of U.S. Christmas trees come from farms in Oregon, North Carolina, or Michigan.

Cut Christmas trees are a commodity, tracked by the U.S. Department of Agriculture just like corn or soybeans.

These USDA aerial images show tree harvest patterns over 12 years in Ashe County, North Carolina. It takes an average of seven years for a tree to grow to a sellable height.

Harvest patterns are not always uniform. In some areas, trees are harvested from one field while those in neighboring fields are left to grow. On other fields, trees are thinned over time.

Aerial imagery from the USDA is archived by EROS and available to the public at no charge, at Christmas time or any time at all.

These images show the Filchner Ice Shelf on the coast of Antarctica that faces the Atlantic Ocean. In the austral winter of 1986, the front edge of the Filchner Ice Shelf broke off into the sea, forming three large icebergs. This was a major, long-awaited calving.

Most images in Earthshots are in “false color”; they are red/green/blue composites, representing three bands of Landsat data. These images of the Filchner Ice Shelf, however, represent only one band of near-infrared reflection, so they are grayscale.

An ice shelf is a huge sheet of ice, connected to land but extending out into the ocean. Ice shelves develop mainly from glaciers flowing slowly downhill toward the ocean. “Upstream,” the ice shelf rests on land, but “downstream,” the ice shelf extends out onto and into the ocean, mostly below sea level.

The Filchner-Ronne Ice Shelf is by volume the largest ice shelf on Earth. It is really one ice shelf, nominally divided by Berkner Island.

Ice shelves are part of a cycle. Winds carry water (as clouds) to Antarctica, where it falls as snow, compacts into ice, flows slowly as glaciers into ice shelves, and then slowly progresses to the ocean, where chunks break off and are carried away by ocean and wind currents. These chunks are icebergs; the birth of icebergs (from glaciers, ice shelves, or larger icebergs) is called calving.

It is widely known that most of an iceberg lies under water; this is also true of ice shelves. When a large piece of ice shelf calves into the ocean, it does not drop and splash down into the water, because the front of the ice shelf was already floating on water. In fact, the ocean’s tides lift and drop the ice shelf every day; this is called hinging, and the place where the ice shelf connects to the “shoreline” bedrock is called the hinge-line, since the outer shelf swings up and down from it.

German scientists learned that the Filchner-Ronne Ice Shelf is two-layered. The top 150 m of ice came from snow and glaciers, but the bottom 80 m of ice came from the water below. This bottom layer is clear and bubble-free. The top layer is hard but snowy and bubbly. These bubbles (or “voids”) allow scientists to study atmospheric gasses trapped in the voids, by coring the ice.

Antarctica has 90% of the world’s ice. Scientists are very interested in the net gain/loss of this ice mass because of its implications for world climate and sea level.

You might have noticed that fire scars of varying size show up in some of these images. These fire scars show up as red or maroon against the green vegetation. Fires are a part of life in the boreal forest, but in 2016, an unusually intense forest fire, fueled by dry conditions and high winds, devastated the region.

The 80,000 residents of Fort McMurray were forced to evacuate, the largest evacuation on record in Canada. The fire destroyed 2,400 structures in and around Fort McMurray, and at least another 500 were damaged. Many structures still standing suffered smoke damage.

At its peak, the fire moved 30 to 40 meters (98 to 131 feet) per minute. It burned a total of 589,552 hectares (nearly 1.5 million acres), and part of that area is shown in the series of images. Using shortwave infrared (SWIR) and near-infrared (NIR) bands to help penetrate clouds and smoke and create false-color images, Landsat shows the burned area in dark red. It’s clear that Fort McMurray was quickly surrounded by the blaze.

Landsat’s infrared sensors are valuable for producing burn severity maps and other products quickly after images are acquired.

In the summer of 1988, a wildfire ravaged the world’s first national park, consuming 1.2 million acres in and around the Greater Yellowstone Park ecosystem. Landsat imagery became an important record of the burn severity and recovery.

As we celebrate the 100th anniversary of the National Park Service, which was established to better manage Yellowstone and other national parks within the Department of Interior, Landsat continues to prove the outstanding value of its land-monitoring mission. The June 2016 image, captured by Landsat 8, portrays the widespread recovery of tree cover and other vegetation within the 28-year-old burn scar.

The national park’s western border is easily evident in images acquired shortly before and after the fire, on Sept. 22, 1987, and again on Oct. 10, 1988. A prohibition on logging in the national park is revealed in a dividing line of land use that shows dark green forests to the right of the park boundary, and the pink and light green hues of forest clearcuts to the left.



Yellowstone’s healing since the fire is obvious in the time-series views as well. Landsat 5’s shortwave infrared, near-infrared, and red bands combine in the October 1988 image to reveal vibrant red burn scars above and below Yellowstone Lake. In 2016, the scars have faded beneath the lush, green forest canopies and resurgent grasslands.

In these Landsat images, the old forest is dark green. In the 1987 image, this forest is occasionally broken up by lighter green grassy meadows or grassy plains. Geyser fields are pale blue and white. In a few places, a pink tinge may indicate old burn scars or dormant plants.

The August 23, 1988, image was acquired when many fires were active. Smoke obscures some of the land, showing up as blue because the image uses infrared wavelengths of light. Land just burned is dark red. Lighter red patches are less severely burned.

The band combination of shortwave infrared, near-infrared, and visible green highlights the changes in vegetation caused by the fires and recovery. Dark red burn scars fade over time as vegetation recovers. Grasses and wildflowers grow out of the ashes, and young trees begin to take root and grow. These light green areas start replacing the red and pink from the burn scar.

As intense as the fires were, studies showed that less than 1 percent of soils were heated enough to sterilize the soil to kill belowground plant seeds and roots. Grass actually prospered in the rich soil immediately after the fires because of the release of nutrients and the decrease in shading from shrubs and trees. Less competition with other plants for resources also allowed grass to flourish.

Even though grass flourished and saplings soon emerged, the recovery is gradual. Even in the 2011 and later images, the burned areas from 1988 can still be seen. The high elevation in this area causes a short growing season. With the hot, dry summers and cold, harsh winters, the forest will not return to its prefire conditions for decades. But recovery will continue.

A few new fires show up in the later images to show that fire continues to be a part of the Yellowstone wilderness.

It may seem surprising that wildfires burn in Greenland, a huge island of ice and glaciers. But fires do happen there. Earth-observing satellites detected a fire in a remote area of western Greenland in August 2017.

A relatively dry summer may have contributed to conditions that led to the igniting of willows, shrubs, grasses, and mosses in this coastal area.

Landsat’s shortwave infrared (SWIR), near-infrared (NIR), and red bands combine to clearly show the difference between burned and unburned vegetation. Hazy smoke rises from the burned area to mix with a few bright, white puffy clouds in the August 12 image.

The bushfire season in northern Australia generally runs from May to October. 2023 was an especially intense year in the north. Select infrared imagery from the Landsat archive was used here to produce a rolling mosaic timelapse of the landscape in eight day segments. Each new segment of imagery reveals fresh burn scars, increasing in size and frequency in October and November. Dry winters, fuel load and rising temperatures all play a role in the Australian bushfire season. Landsat imagery helps communities in Australia plan for fires and work to restore habitat. 

Fires burned across California in late 2019. Fall is the state's most dangerous season for wildfires, propelled by dry and windy conditions. In recent years however, the fall fire season has been starting earlier and ending later.

A series of images from the MODIS sensor on NASA's Terra and Aqua satellites show the Kincade Fire in northern California. This fire started on October 23rd. By the end of the month it had burned 77,758 acres. A strong wind from the northeast is evident as smoke billows from the fire toward the Pacific Ocean.

Europe's Copernicus Sentinel-2 satellites captured more detailed images. The fire burned some areas already hit two years ago by the Tubbs Fire. Strong winds created small isolated fires seen as a pattern of hotspots in the images. Evacuation zones included the entire towns of Geyserville, Healdsburg, and Windsor, and the northern part of Santa Rosa.

As the Kincade Fire burned in the north, several fires hit the Los Angeles area. A Landsat 8 image from November 6th shows scars of the Saddle Ridge, Getty, Tick, Easy, and Maria Fires. The Maria Fire was the largest in this region. It burned nearly 10,000 acres in just 6 days.

Data from these three satellite systems complement each other to provide a complete picture of wildfires statewide.

Massive wildfires scorched nearly 780,000 acres of farm and ranch land in Oklahoma and Kansas in March 2017. The fires started on March 6, and dry conditions and high winds caused the fires to spread rapidly. The series of blazes damaged farms and ranches, and destroyed miles of fences. Many families lost most of their cattle herd, and several homes burned. The fires were considered contained by March 22.

In Clark County, Kansas, the small town of Ashland, located about 40 miles south of Dodge City, had to be evacuated. Fire scars are prominent in Landsat 8’s March 17 image in vivid maroon tones surrounding Ashland, while green blocks of cropland are scattered throughout the image.

Landsat’s shortwave infrared (SWIR) band measures reduced moisture content in soil and vegetation. When combined with its near-infrared (NIR) band, which helps reveal actively growing vegetation, Landsat produces highly accurate images and maps of burned areas. Landsat data can also be used to map the severity of the burn impact on soils and vegetation and to monitor the greenness or recovery of vegetation after the burn.

A series of wildfires erupted along the coastal region north of San Diego, California, in mid-May 2014. The first wildfire (Bernardo Fire) began on May 13, followed by several additional fires that occurred over the following days. At one point, firefighters were battling at least eight active wildfires and over 175,000 evacuation notices were issued.

The Landsat 8 image (left) was acquired on May 9, 2014, and shows the area before the fires began. The Landsat 7 image (right) was acquired eight days later. The red tones show numerous areas that were burned as of May 17, 2014.

The repetitive imagery provided by the Landsat satellites allows officials to evaluate the destructive impacts and monitor future recovery after disaster events such as these wildfires.

Smoke filled the skies over western Canada and even much of the United States in May 2023. The source was several wildfires in Alberta and British Columbia.

Near the end of May, rain and cooler temperatures finally brought some relief for the out-of-control fires.

Wildfires burned across Lebanon in mid-October 2019. A pair of images taken just 10 days apart by the European Space Agency’s Sentinel-2A satellite show the burn scar from one of the larger wildfires.

North of the fire scar is the country’s capital, Beirut. The October 18 image reveals several bright spots on city streets from numerous fires of a different type. These fires were set by protesters, burning tires and other debris to register frustration with government corruption, new taxes, declining public services, and an economic crisis.

While Sentinel’s shortwave infrared and near-infrared bands capture burn scars, the brightness of reflected light from active fires saturates the sensors to show the locations of the hotspots.

Southeast Australia has a history of severe fire problems, with some historic deadly fires such as the Ash Wednesday fire of 1983, and lesser fires almost every year. The state of Victoria averages about 19 large fires (over 1,000 hectares) per year. These fires are often fast like grassfire but more intense. The winter rains that benefit wheat farming also aid the buildup of plant matter, which becomes highly combustible during the dry summers. Perhaps 60% of the fires in Wyperfeld are started by lightning, with the rest from various human accidents and purposes, including fuel reduction. Since the 1950s, Australians have systematically set controlled fires to reduce the risk of dangerous fires later. Wyperfeld staff currently set fuel-reduction fires along the park’s edges but fight all accidental fires, as required by law.

These fires kill individuals, but communities of living things survive. Studies elsewhere in Victoria indicate that 2–4 years after a fire, the forest floor is again littered with small twigs and leaves, the habitat for many small animals. There are more plant species in the area than before the fire, though frequent burning certainly can kill out some species. Forest studies show that different post-fire stages favor different species; mice do well right after a fire, for example, but some birds do better in long-unburned or intermediate areas. Now that habitat is restricted to “islands” of parkland, there is danger of an entire park being burned out, with no adjacent communities to recolonize the burned areas.

The Landsat images here show a stark change from unburned bush in 1977 to huge burn scars in the later images. The age of the scars can be estimated by their color; old scars are almost as dark as the bush, half-regrown scars are only pink, and the newest scars are very bright.

On an average day during the fire season, multiple wildfires burn in the western United States. For example, 216 fires were active on July 7, 2017. Firefighters were battling 27 of these fires through ground and air support.

A few of the larger fires in early July were in Arizona, Washington, and Utah. As with many wildfires, Landsat plays an important role in monitoring the spread of these fires and is the primary data source for mapping burn severity after the fires are contained.

In these Landsat images, fresh fire scars are magenta, forest areas are green, cropland is bright green, and grasslands are indicated by duller green and pink hues. Landsat’s shortwave infrared (SWIR), near-infrared (NIR), and red bands combine to provide an accurate distinction between burned and unburned vegetation.

The fires shown here started in mid- to late June and are all in steep, rugged terrain, which makes fighting the blazes difficult. The largest of these four fires is the Brian Head Fire in southwestern Utah, which has consumed more than 71,000 acres.

Landsat 7 and 8 acquisitions help scientists continue to monitor the numerous wildfires in the West. They provide valuable data that assist land managers in understanding the impacts of fires and the need for resource rehabilitation and hazard mitigation.

These two Landsat images show the urban area around Cape Town, South Africa. The more recent image (right) reveals scars from several fires that broke out in early March 2015, and were intensified by strong winds and hot summer temperatures.

The dark fire scar on the left side of the March 11 image is from a fire that had started ten days earlier and burned more than 5,000 hectares (12,000 acres). The dark scar on the right side of the same image is from the Jonkershoek Fire, which started March 9 and was still active at the time this image was collected. About 4,000 hectares (10,000 acres) were burned before this second fire was contained.

Landsat imagery is a valuable tool for the mapping and measurement of burned extent and lost vegetation due to wildfires. As the landscape begins to recover, Landsat will also be useful for monitoring the area’s regrowth and restoration.

The waves of sugar cane that once defined the Hawaiian island landscape of Maui, have slowly given way to non-native annual grasses in recent decades. Those grasses have become a fire hazard along the way. 

The closure of central Maui's last large cane mill in 2016 opened up some 36,000 acres for new growth. Some of those acres burned in 2019 during one of the island's most active fire seasons. This false color Landsat image from July of that year shows the area after the fields went fallow, but before the fires took hold. What had been well-defined cropland in 2014, had become masses of brown vegetation. The second 2019 image shows the aftermath of a summer fire that blackened 25,000 acres. 

Landsat imagery and vegetation data from satellite-derived land cover datasets can help communities in Hawaii plan for fires, and work to restore habitat.

Landsat satellites acquire useful data on wildfires around the world. Their near infrared and shortwave infrared imaging allows for detection and mapping of fire, smoke, and burn scars often in remote areas.

In California: the Dixie Fire  near Lake Almanor and the Caldor Fire near Lake Tahoe.

In Israel: over 6,000 acres in the Jerusalem Hills just west of Jerusalem.

In Canada: active fire just west of Lake Winnipeg and a large burn scar from earlier in the summer.

In Russia: numerous fires and burn scars in the Siberian region.

In Greece: more than five times the yearly average of fire activity.

In 1947, Copenhagen established the Five Finger Plan. The plan for the city’s growth designated five corridors of urban development, which were along railway lines to provide convenient transportation to Copenhagen’s business district in the central part of the city. Planned suburbs were to be built along these corridors and linked together like beads on a string.

The development plan resembles a hand with five fingers stretching out away from the city center. The plan allowed for controlled urban growth while leaving space open for recreation and agriculture. These green spaces were to occupy the land between the fingers.

As the series of images shows, the five fingers and hand shape are indeed vaguely recognizable. In these false-color images, the developed areas are shades of purple. Buildings and pavement are very reflective. On the other hand, water reflects very little sunlight, so it shows up as black.

Heavy rains starting in June have brought the worst flooding the country of Paraguay has ever seen. Thousands of residents have been displaced due to flooding of the urban and rural areas along the Paraguay River in this central South American country.

These images, acquired by Landsat 8 on April 14, 2014, and July 19, 2014, show the Paraguay River, north of the city of Asuncion. The April image shows the area before the flooding began. The July image shows the dramatic change due to the flooding.

Future Landsat data acquisitions will be useful in monitoring the affected areas.

In June 2014, southeastern South Dakota received record amounts of rainfall, and parts of neighboring states also received excessive rainfall due to a series of severe storms. As rivers overran their banks, many roadways became impassable and the  rising waters damaged many homes and businesses. This area is an important agricultural region, and the heavy rainfall and accompanying hail damaged many of the recently planted corn and soybean crops.



The second image clearly shows the Vermillion River and the Big Sioux River flooded over their banks. The lower right corner  of the second image also has darker tones mixed throughout the agricultural areas (bright green). These darker tones suggest potential flood damage to the crops in this region.



Landsat images such as these can be an important tool for evaluating the damage to local crops and for monitoring the agricultural recovery and replanting efforts on a regional scale. The Landsat imagery will also be useful for monitoring the overall distribution oft floodwaters as they recede and move downstream.

 

The Balkan area of Europe received extraordinary amounts of rainfall during the month of May 2014, which led to the region’s worst flooding in more than 120 years of record keeping.



These Landsat images, acquired May 7 and May 23, show the area of the Sava River in southeastern Europe. The overflowing river and subsequent flooding of the area is clear in the second image.



As the flooding recedes and recovery efforts begin, Landsat imagery will be useful in monitoring the area.

Europe's Copernicus Sentinel-2 satellites revealed flooding at Tweed Heads, New South Wales. Heavy rain that persisted for days in late February 2022 caused widespread flooding on Australia's east coast.

The Harmonized Landsat and Sentinel-2 (HLS) project combines the two satellite programs to enable global observations of the land every 2–3 days at 30-meter resolution. As they flooded, the Tweed River and Terranora Creek carried runoff sediment into the ocean, shown with the lighter blue shade in the Sentinel images.

The USGS distributes Sentinel data through its EarthExplorer portal.

The cut flower industry can be seen in Landsat images near the lake in both outdoor fields and in glass greenhouses. The greenhouses are silvery in these views. The fields are a mix of green, tan, and purple. Tan and pink are fallow fields, and the green fields have growing plants. These fields and greenhouses have expanded over the time frame covered by these images.

The flowers grown in the region include roses, carnations, statice, alstromeria, lilies, and hypericum.

Since 1986, the nature of agriculture around Lake Naivasha has changed from mostly ranching to floriculture. The flower industry especially has led to increased population in Naivasha and the surrounding area. From 1969 to 2009, the population of the Naivasha Division increased more than 750%.

The flower farms use a lot of water from the lake and send nutrients and chemicals back to the lake. In addition, the increased population is placing more pressure on the freshwater resources in the region. As a result, the chemistry of the lake is changing. More blue-green algae and tiny crustaceans are appearing in the lake, which are food for flamingoes. The pink birds usually flock to lakes salty enough to find this food, so it was unusual to see them in abundance at Lake Naivasha.

Floriculture began around Lake Naivasha in the early 1980s. During the 1990s and early 2000s, the amount of land dedicated to floriculture rapidly increased, changing from grassland and shrubland to flower farming. The increased water use led to a drop in the water level of the lake and an increase in farm runoff laden with agro-chemicals.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Founded by the Spanish in 1565, St. Augustine, Florida is the oldest settlement of European origin in the United States. The Spanish fortress of Castillo de San Marcos in St. Augustine was built from 1672-1695 and is made of coquina, a soft, impact-absorbing stone composed of sea shells.

Spanning the southern tip of the Florida Peninsula and most of Florida Bay, Everglades National Park is the only subtropical preserve in North America. It is the only place in the world where alligators and crocodiles exist side by side.

On November 15, 2013, a new Global Forest Change survey was released. This online tool shows the forest change that has occurred worldwide from 2000 to 2012, and is based on the global repetitive observations by Landsat satellites during this time period.

These example images show the observed changes in forest cover north and east of Tuscaloosa, Alabama. They also show the change after an EF5 tornado caused massive destruction on April 27, 2011.

The two Landsat images show the forested areas in 2000 and 2011. The tornado path can be clearly seen in the second image.

The derived Global Forest Change map for the same area (right) is based on repeated Landsat observations from 2000 to 2012. Red indicates net forest loss, and blue indicates net forest gain. Magenta indicates mixed activity (gain and loss) within this time interval. Green indicates no change to the forest cover, and black indicates nonforest.   

The overall mixed colors in the Global Forest Change map help to record the dynamic nature of the local forest land cover. The red streak clearly shows the forest loss caused by the 2011 tornado.

The new Global Forest Change Web site is the result of collaboration between USGS, NASA, the University of Maryland, and Google. See the interactive map of global forest change at: http://earthenginepartners.appspot.com/science-2013-global-forest

The water that is used to grow these crops dates back to the last ice age. Known as fossil water, it has been buried deep underground for about 20,000 years.

The agricultural fields are round because of a technique called center-pivot irrigation. Sprinkler systems move around a central pivot to water the field. The technique provides better control of water and fertilizer use, which is important where water can evaporate quickly. The fields shown in these close-ups vary in size. The largest circles are about 1 kilometer across.

The drawback with this technique is that water in these aquifers is not recharged. Rainfall here averages only 100 to 200 millimeters per year, and that makes the groundwater in the area a nonrenewable resource.

The amount of water stored in the aquifer under the desert ranges from 252 to 870 cubic kilometers. Hydrologists believe it will only be economical to pump this groundwater for about another 50 years.

Groundwater irrigation here is only possible because of another nonrenewable resource—oil. The Saudi government used income from the sale of oil to fund these irrigation systems. Saudi Arabia spent billions of dollars developing agriculture in the last 15 years of the 20th century. In 2008, the Saudi government began phasing out domestic wheat production. By 2016, the country ended its domestic wheat production program because of concerns about the depletion of water reserves. However, since the announcement to phase out wheat, some farmers have begun growing forage crops to feed livestock, a less efficient use of water.

Cracking ice on the Arctic Ocean fractures like broken glass in far northern Canada. Uninhabited Eglinton Island is the land on the right. Fingers of land from Prince Patrick Island stretch downward in the upper left of the image.

Besides some recovery from the 1988 fires on the west side of Yellowstone Lake, this series of images shows the effects of another fire.

Frank Island is the largest island in Yellowstone Lake. The island was set up as a protected area for ospreys that nest on the island. The public is not allowed on the island during the summer. Only a small picnic area on the southeast point is open for visitor use.

On August 8, 2003, lightning struck Frank Island. An inferno quickly engulfed nearly all of the old growth trees. Most of the forest on the island burned.

The first image in this series is from one week before the lightning strike that started the fire. The island appears deep green in the middle of the lake. In the other images, virtually no vegetation remains on the island. The green was replaced by pink, which indicates barren ground.

If you like being connected to the world everywhere you go with a smartphone or other device, then you have a desolate salt flat in northern Chile to thank.

The Salar de Atacama salt flat has the planet’s largest deposit of economically recoverable lithium, a key ingredient in rechargeable batteries. Landsat imagery shows the expansion of the lithium mining operations from 1991 to 2018.

Located in Chile’s Atacama Desert, the salt flat has hard crusts of sodium chloride. Lithium-rich brine is pumped to the surface and sent via canals to evaporation ponds. The water evaporates efficiently in the dry environment and leaves behind concentrated salts.

The ponds vary in color because of varying amount of salts in the water. The brighter ponds contain more concentrated salts. The deep blue ponds indicate more water content.

Images created from Landsat data help monitor changes taking place on the Earth’s surface, along with the effects that resource extraction has on the local environment.

The Funny River Fire was first discovered on May 19, 2014. By early June, it had burned almost 200,000 acres in south-central Alaska, including much of the Kenai National Wildlife Refuge.

The Landsat 8 image on May 4 shows the area before the fire began. Heavy smoke covers the Kenai Peninsula in the May 20 image, and this image also shows some of the areas of active burning (bright orange) along the edges of the wildfire area. On June 5, Landsat 8 captured the total extent of the burned area.

Many projects were headed by loyal party leaders with no technical skills, which is another reason the canals were not more effective. Teachers, technicians, and other skilled (usually urban) professionals—hated by the Khmer Rouge as corrupting urban influences—were executed. Thus, primarily inexperienced and unskilled citizens, including the evacuated city-dwellers, were forced to work in the countryside growing rice and building these irrigation works, with rigid work quotas and hard, slave-like conditions. The lack of experience led to inefficient canals that occasionally collapsed in the rain.

Not only were the canals poorly constructed, but they also were built in straight lines, regularly spaced, at right angles along the 1-km gridlines of their military maps, ignoring hills, villages, and other topography. Some claim that many of the canals actually did more harm than good, disrupting natural water supplies and encouraging erosion. This pattern can be seen in most of these images. In more recent years, the irrigation system built during the Khmer Rouge regime is much less defined in satellite imagery.

It appears in the images that each district had to dig a certain amount of ditches, whether needed or not. Indeed, workers had rigid daily quotas, so that some finished early and some could never finish. There were strict decisions about which varieties of rice were acceptable, diminishing the diversity of varieties which had adapted to local conditions.

Though it is likely that by the end of the Khmer Rouge regime canal construction expertise had improved, the post-Khmer Rouge government had to devote considerable resources to repairing irrigation works. One official said 80% of the projects had been poorly constructed, though it varied by region.

Although many of the canals were poorly built, some of them can still be used. The Cambodian Prime Minister Hun Sen started supporting the re-digging of the canals in 2005, and now that the people who are rebuilding them are no longer under the Khmer Rouge, they get paid a small amount, and the crops that are harvested aren't taken away by the government.

Gaborone is the capital and largest city in Botswana. Its current residential population is estimated at 250,000 within the city limits (450,000 when including the outlying areas).

Almost all of this urban development has occurred within the last 50 years. Development of initial infrastructure began in 1963, and the city was formally established in 1966 on the eve of Botswana’s independence. Since that time, Gaborone has experienced rapid urban growth. This expansion is expected to continue as economic and commercial entities become further established there.

The Gaborone Dam, south of the city, was completed in 1964 and provides critical water supply for the growing city. Within the last decade, the water levels have dropped significantly due to increasing water usage along with climate factors. In the early 2000s, the reservoir was estimated to be 80 percent full; as of December 2013, the water level of the reservoir reached its lowest point since the dam was built, at approximately 13 percent full.

These Landsat images show the city of Gaborone and the surrounding area in 2001 and again in 2013. These images show the urban growth (gray) extending into the landscape in the later image. The images also show the reduction in size of the reservoir over the past 12 years.

As urban populations continue to grow, the changing landscape and water resource management become important issues for community leaders. Landsat imagery provides repetitive views of the Earth’s surface which can help monitor urban growth patterns and other changes to Earth’s resources.

The Ganges River forms an extensive delta where it empties into the Bay of Bengal. The delta is largely covered with a swamp forest known as the Sunderbans, which is home to the Royal Bengal Tiger.

Center pivot irrigation systems created these circular patterns in crop land near Garden City, Kansas. The red circles indicate irrigated crops of healthy vegetation. The light-colored circles represent harvested crops.

These Landsat images feature the significant growth in the use of center-pivot irrigation—essentially enormous sprinkler systems—in Kansas between 1972 and 2021. The Arkansas River flows east just south of Garden City in southwestern Kansas. From 1972 to 1990, Garden City's population grew from about 15,000 to about 24,000. The town's population as recorded by the 2020 Census stood at 28,151.

Much of the former shortgrass prairie of western Kansas is now irrigated cropland. Common crops in this area are corn, wheat, and sorghum. Red areas in the images are healthy vegetation. Light-colored cultivated fields in the images are fallow or recently harvested wheat fields.

These images show center-pivot irrigation systems (the small circles) multiplying between 1972 and 1988. From 1969 to 1987, irrigated acreage in Kansas increased by 62%, from 1.5 million acres to 2.4 million acres. In the five years from 1984 to 1988, Kansas farms with center-pivot irrigation systems increased 19%, from 2,630 farms to 3,122 farms.

This area uses irrigation water from the High Plains Aquifer—also known as the Ogallala Aquifer—one of the world's largest aquifers, which underlies an area from Wyoming to Texas. Landsat images are useful for measuring irrigated crop acreage, a key component of modeling aquifer response to changes in water use. Landsat is also used to monitor the depletion of the aquifer, which is affected by not only the irrigation but also drought.

Geometric shapes lie across the emptiness of the Sahara Desert in southern Egypt. Each point is a center pivot irrigation field a little less than 1 kilometer (0.6 mile) across. With no surface water in this region, wells pump underground water to rotating sprinklers from the huge Nubian Sandstone aquifer, which lies underneath the desert.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Georgia is home to Okefenokee Swamp, a unique area of primitive wetland that provides sanctuary for hundreds of species of birds and wildlife, including several endangered species.

This scar on an arid landscape is the dry riverbed of the Ghadamis River in the Tinrhert Hamada Mountains near Ghadamis, Libya.

Ethereal swirls of grease ice appear turquoise against the midnight blue of the northern Baltic Sea near the Aland Islands (red) between Finland and Sweden. An early stage of sea ice formation, grease ice consists of a viscous mix of tiny ice crystals and resembles an oil slick on the ocean's surface. Wind and currents constantly shape and reshape grease ice into surreal, ghostly patterns.

At nearly 244 meters tall, Gibe III is Africa’s tallest dam and the continent’s third largest hydroelectric plant. Its estimated production capacity is 6,500 GWh a year.

The first large dam on the Omo River, Gibe III takes its name from a tributary of the Omo, the Gibe River, on which two smaller dams were previously built. The Gibe I hydroelectric turbine was installed in 2004, and Gibe II in 2010. Gibe IV and Gibe V are planned to be built on the Omo downstream of Gibe III.

Construction of Gibe III began in 2006. The reservoir, now 155 kilometers long, began filling in February 2015. The reservoir fills the entire canyon that the river flowed through. The dam began generating electricity later in 2015 and was fully commissioned in December 2016.

The electricity generated by the dam is also exported to Kenya and other countries, bringing in hundreds of millions of dollars of revenue for Ethiopia. Electricity can also be delivered to Ethiopia’s rural areas, where just 26.5% of the population had access to electricity in 2015.

Located 450 kilometers south of the capital Addis Ababa, the dam is also used to regulate floodwater and provide water for irrigation. However, the dam ended the natural annual flooding that brought nutrients to the banks of the Omo River. The lack of floods makes it more difficult to grow food there.

An artificial regulated flow through the dam was intended to mimic this natural flood pulse. But the dam traps sediment, so even with regulated flow through the dam, there will still be impacts on wildlife and farming because of the reduced nutrients from this sediment.

Because the Omo River accounts for 90% of the inflows to Lake Turkana in Kenya, there are major effects on the water levels and water quality of that lake, especially now that the water is used for other purposes such as large-scale irrigation. Furthermore, the reduced flow from the Omo causes increased salinity in Lake Turkana, which can affect some fish species.

The great thing about hydropower is that it’s a renewable nonpolluting source of power. Once it’s up and running, operation costs are relatively low, and the energy supply is very reliable.

In the United States, most of the best locations for hydropower have already been taken (such as Hoover Dam near Las Vegas and the Glen Canyon Dam). Other countries are starting large hydro projects to further development and provide reliable power for more communities. In Ethiopia, for example, a series of large dams on the Omo River provide electricity for the country and enough to export to neighboring countries. They also provide irrigation water for large-scale agriculture.

Hydropower projects of this scale often come with downsides as well.

Large hydropower projects can have a massive effect on the landscape. Reservoirs can change local ecosystems and fish habitat, and sometimes displace large populations of people. In the case of the Gibe III dam, the rapid changes could have substantial effects on the people living downstream who depend on the river’s regular pulse floods for farming and fishing.

Gibe III is the third hydropower plant on the Omo River, what they’re calling a hydroelectric cascade.

The Omo River has a unique geo-political dynamic. The river is entirely contained within Ethiopia’s borders. However, the river empties into Lake Turkana, which lies almost entirely within neighboring Kenya to the south.

Another forest reserve called Gilli Gilli lies directly south of Okomu. Gilli Gilli has experienced less deforestation than Okomu—limited to smaller areas of degradation on its northern side. The low rate of degradation in Gilli Gilli could be because few settlements are located near it. This area is more inaccessible than Okomu.

In Okomu, a farming system called Taungya was introduced in 1945. The plan allocated parts of the reserve to food crops. Trees were required to be planted on the same farm plots and would be allowed to be harvested as timber. In Okomu, however, migrant farmers often did not plant trees. In Gilli Gilli, however, the Taungya system was not introduced.

The Landsat images do show moderate deforestation in its northern part, gradually spreading toward the southeast. However, this area’s inaccessibility has spared it from large-scale forest degradation.

The remote ice fields of southern Chile have seen some dramatic change over the past three decades; change made clear by Landsat's deep archive of imagery.

In 1987, the terminus of Erasmo Glacier was at the end of a low sloping valley. By 2015 it had retreated almost 3 kilometers, and formed a water body referred to as a proglacial lake. The end of the glacier now lies about 4.3 kilometers from where it was in 1987.

Landsat imagery reveals several icebergs in the lake. Over time, fewer icebergs appear, until the 2021 image shows an uncluttered body of water.

Data from Landsat provide consistent measurements of remote glaciers over time, allowing long term monitoring.

A stable glacier advances a little in the winter and retreats the same amount in the summer. Bear Glacier likely did this and gradually built up a terminal moraine. (A moraine is a buildup of glacial material, and a terminal moraine is one that is built up at the end of the glacier.)

During the last 100 years in Alaska, the annual average temperature has increased by about twice the global annual average temperature change. A temperature increase like this can change the regular pattern of glacial advance and retreat.

Between 1950 and the 1990s, Bear Glacier retreated 1.55 kilometers (1 mile). Small icebergs were calving into a lagoon that had developed. By 2004, the glacier’s floating terminus calved, causing an additional 2 kilometers (1.25 miles) of retreat. Between 2000 and 2007, the terminus retreated another 3.5 kilometers (2 miles). Large icebergs now float in the lagoon, visible in the Landsat images as light blue spots in the water.

The visible impact of climate change on the Earth’s surface is often clearest in the Arctic’s receding glaciers and swelling glacial lakes.

Southeastern Alaska’s Harlequin Lake is one of the fastest-growing in North America. These false color Landsat images show the rapidly-retreating Yakutat Glacier, which feeds the lake.

Landsat can be used to illustrate the lake’s expansion by more than 15 square miles since 1999. The glacier flowed deep into the lake’s northeastern edge in the summer of 2000, the thicker ice above it shown as deep turquoise.

The glacial retreat is starkly apparent a decade later as the icy edge pulls back and the thick turquoise tones give way to reveal clear lines of movement. The upper lake is nearly free of ice by 2020.

 

The island nation of Iceland is replete with unique natural wonders and geothermal features, with a rugged interior defined by ice caps, glaciers, and volcanic peaks.

Iceland had 269 named glaciers as of the year 2000, but ice has retreated in the face of warming temperatures. By 2014, Ok Glacier in western Iceland had lost so much mass that it was no longer considered one at all. Icelanders now refer to it simply as “Ok,” the name of the volcano upon which it rests.

Landsat has recorded its decline for nearly five decades. This border shows Ok’s glacial footprint in the year 2000.

The glacier spilled well outside that border in 1973. A growing gap between the glacial mass and the volcano’s summit crater is apparent by 1987. By 2019, just a smattering of ice remains. Declines in glacial mass are also evident in larger glaciers to the east of Ok.

Glaciologists in Iceland who analyzed 80 years of records and concluded in 2014 that the country will lose all but its highest-elevation glaciers by the year 2200 if shrinkage continues at its current rate.

USGS uses repeat photography of glaciers to quantify changes in glaciers over time. Repeat photography is a technique in which a historical photograph and a modern photograph, both having the same field of view, are compared.

For example, oblique aerial photographs of Bear Glacier were taken facing north and show glacial retreat along with icebergs floating in Bear Glacier Lagoon.

Photographs taken from the ground look north and were from the same location on the eastern part of the terminus of Bear Glacier. In the 96 years between photographs, Bear Glacier has retreated more than 3 kilometers (1.9 miles) and thinned by as much as 200 meters (656 feet). Only a very small part of Bear Glacier is visible from this location today, and the terminus is obscured by the trees.

Glen Canyon Dam near Page, Arizona, creates Lake Powell. The 710-foot-high dam was completed on September 13, 1963, about 9 years before the first clear Landsat 1 images were acquired. The dam also generates electricity. From 1980 to 2013, its average annual gross electricity generation was about 5 billion kwh. (kwh = kilawatt-hours, a measure of a power station’s electricity output.) Its electricity generation varies based on the amount of water that flows into the lake, which is influenced by precipitation.

In the Landsat series of images shown here, we begin with 1972 when the lake was still filling. In 1984, the lake was at one of its highest water levels.

Near the dam is the city of Page, Arizona, which began in 1957 as a housing camp for workers building the dam. Page is now a major resort area. Its 2021 population was 7,375.

At various marinas on the lake, tourists can rent houseboats and other recreational watercraft. Wahweap is the largest marina on Lake Powell. This marina needs to move based on the lake’s water level. Antelope Point is the newest marina on Lake Powell, established in 2004.

Antelope Island is in the center of these images. It looks a lot less like an island in the later low water level images. The National Park Service dug a channel on the island’s north end called Castle Rock Pass. Even though it begins to look more like a peninsula by the 2005 image, it is still called Antelope Island. The channel around the north side of the island is navigable when the lake’s water level is 3,620 feet or higher.

Researchers from the University of Maryland and USGS have mapped changes in forests globally from 2000 to 2013. The maps displayed here are from that database and are paired with a corresponding Landsat image.

The study defined trees as all vegetation taller than 5 meters. In the forest change map, green indicates forest extent, and red is forest loss during the period 2000–2013. Any blue that appears is forest gained during that time period. Black is land that was non-forest during the time period.

The study used data from over 650,000 Landsat scenes and used 143 billion 30-meter Landsat pixels.

142 million years ago, an asteroid or comet slammed into what is now the Missionary Plains in Australia's Northern Territory, forming a crater 24 kilometers in diameter and 5 kilometers deep. Today, like a bull's eye, the circular ring of hills that defines Gosses Bluff stands as a stark reminder of the event.

On January 15, 2014, lightning sparked a brushfire in Grampians National Park in the State of Victoria in southeastern Australia.  The combination of dry, hot weather and strong winds contributed to a rapidly spreading complex. The fire became so intense it created a 12-km (7.5-mi) wide convection column that created its own weather, generated lightning strikes, and sparked many smaller spot fires.  



Residents of the town of Halls Gap, just south of the burned area, were evacuated. The fire claimed at least one life and scorched over 53,000 hectares (131,000 acres) before it was contained on January 21.  



These two Landsat 8 images show the area on January 12, 2014 (before the start of the fires) and again on January 28, 2014. The dark tones in the later image depict the burned areas.



The information contained in Landsat images is useful for mapping wildfires, along with many other types of land cover change.

Other mines also continue to expand, even in the Landsat era. The Hull-Rust-Mahoning Mine near Hibbing is one of the biggest mines in the world. Some call it the “Grand Canyon of the North.”

Rather than a natural wonder, the 535-foot-deep mine is another huge open pit gouged into the Mesabi Range and expanded over the decades. In the Landsat images, it’s still the tailings basin that stands out and takes up more land area. The mine itself is between the tailings basin and the city of Hibbing. Both the basin and the mine expand during this time series of Landsat images.

Another tailings pond expands farther to the south. This is the Keetac mine and tailings basin.

Another USGS aerial photo shows part of this area pre-Landsat. The Hull-Rust-Mahoning open-pit mine is just north of Hibbing in 1953, but the current tailings basin had not been established yet.

The reservoir behind the largest hydropower plant in Africa has begun filling. Under construction since 2011, the Grand Ethiopian Renaissance Dam (GERD) is 1.1 miles long, 509 feet tall, and spans the Blue Nile River in Ethiopia.

The GERD reservoir is in a deep gorge, so its surface area is relatively small compared to its volume. This means less water will be lost to evaporation than in desert reservoirs. The lake’s capacity is about twice the volume of Lake Mead.

Including the Aswan High Dam in Egypt, which forms Lake Nasser and has the capacity of four times the volume of Lake Mead, two of the world’s largest dams are now on the Nile River system, in two different countries.

The first phase of GERD reservoir filling began in summer 2020. The curved shape southwest of the main dam is referred to as the Saddle Dam, and the reservoir reached it for the first time in 2022.

Landsat imagery may make it look like the lake is filling at a rapid pace, but filling the reservoir is still a gradual process. Filling too quickly could lead to hydrologic water shortages downstream, especially if a drought hits at the time.

Just west of the mining area, a dark green patch of land emerges in the time series of images. This is a cooperative farm called Granja Porcón. The 12,000 hectares of land in the cooperative were originally grassy plains.

The dark green area on the images indicates the effects of an afforestation project. Granja Porcón includes a nursery that produces over a million seedlings per year, and the forest plantations provide wood as a source of income for the local population. Pine species are planted in this location because of their resistance to cold at high elevation.

Tourists can visit and work alongside the residents of the cooperative in day-to-day tasks, such as milking cows or working in the fields.

What might be mistaken for dinosaur bones being unearthed at a paleontological dig are some of the individual reefs that make up the Great Barrier Reef, the world's largest tropical coral reef system. The reef stretches more than 2,000 kilometers (1,240 miles) along the coast of Queensland, Australia. It supports astoundingly complex and diverse communities of marine life and is the largest structure on the planet built by living organisms.

Like swirls of paint on an enormous canvas, shallow lakes, mudflats, and salt marshes share the sinuous valleys on Iran's largely uninhabited Dasht-e Kavir, or Great Salt Desert.

The water level of the north arm of Great Salt Lake, Utah, has reached a record low elevation of 4,191.6 feet, 1 foot below the previous record. Lower snowpack in recent years has lessened the spring runoff flowing into the lake. These Landsat images show the change in water levels between 2011 and 2015.



Great Salt Lake is a closed lake, with no outlet. Since water leaves the lake only through evaporation, it leaves behind its dissolved minerals, making the lake up to 8 times as salty as seawater.



On the right side of these images are evaporation ponds. Water from the north arm is pumped to these ponds. The water evaporates and salt, potassium, and other minerals are extracted.



The lake’s north and south arms are separated by a railroad causeway, the straight line cutting across the images. Limited water circulates between the lake’s north and south arms through the Union Pacific Railroad Causeway breach, but because of the low water levels, the breach is now dry. The result is even saltier water in the north arm.



A USGS article published in late 2015 provides more information about Great Salt Lake.

 

These images show the dramatic effects of the Great Salt Lake's high water levels in the 1980s. These effects included a great increase in the lake’s area, the opening of the causeway crossing the lake, and the creation of a new evaporation basin west of the lake.

The Great Salt Lake is a terminal lake, with no outlet rivers running to the ocean. Since water leaves the lake only through evaporation, it leaves behind its dissolved minerals, making the lake up to 8 times as salty as seawater.

The lack of outlets also means the lake responds dramatically to change in inflow. Rainy weather beginning in 1982 brought the highest levels in recorded history, peaking in June 1986 and March–April 1987. The lake is shallow for its size—about 70 miles long and 30 miles wide, but only about 40 feet deep. Because the lake basin is so shallowly sloped, extra inflow to the lake makes it rise only slowly, but any rise means a large increase in area. Highways, causeways, and parts of Salt Lake City were flooded or threatened in the 1980s, costing millions of dollars.

Long-term drought and water use led to Great Salt Lake reaching its lowest level on record in November 2022. This low level of the lake can increase dust pollution and reduce mineral extraction, shrimp production, waterfowl habitat, and recreational opportunities.

Landsat imagery shows the lake shrinking from June 2022 to October 2022, then slightly expanding in 2023.

Landsat has been monitoring the lake for over 50 years, and will keep tracking the water level changes.

The western region of Australia's Great Sandy Desert is an area almost devoid of sand, but characterized by complex geology.

In a small corner of the vast Great Sandy Desert in Western Australia, large sand dunes—the only sand in this desert of scrub and rock—appear as lines stretching from left to right. The light-colored fan shapes are scars from wildfires.

Other urban centers near Denver are also growing quickly. While the population of the Denver metropolitan area increased by 84% between 1990 and 2022, Greeley, about 40 miles north of Denver, increased by 80.4% in the same time period.

In these false color images, residential areas are a mottled green, with streets, highways, and other infrastructure showing up in purple hues. The brightest green spots are golf courses, parks, and other areas that have growing green grass. Bright green circles and rectangles are farm fields. In fact, just about everything that is green in these images away from the mountains is irrigated.

Other expansion seen in these images is the petroleum and natural gas industry. An increased number of bright spots indicates more oil and gas wells.

Along Greenland’s western coast, a small field of glaciers surrounds Baffin Bay.

These 2021 images show the seasonal progression of the irrigated crops in this area, from around the peak of the growing season to harvest. The August image is at the height of the growing season, and the November image is after many fields have been harvested. The harvested fields are a conspicuous white and not red because the vegetation has been removed.

From 1975 to 2020, Santiago’s population increased from under 3.5 million to just over 7 million. In the late 1970s, housing shortages were increasing, particularly for the poor. In the early 1990s, Santiago’s elites moved to the northeastern suburbs to escape the city center’s increasing congestion, retail, and rural immigrants. The affluent Barrio Alto district is in this quarter, flanked by the Andes and the San Cristobal Hills.

A squatter settlement existed in the Barrio Alto, housing many domestic servants and workers for wealthy households nearby, until the mid-1970s when the government evicted them. A park in place of the squatter settlement was discussed, but instead one of Chile’s largest shopping malls, the Parque Arauco, was built. The former squatters were resettled in public housing in the southeastern part of the metropolitan area.

This followed the pattern of the military government: slum clearance in the city’s center and northeast, with a shift to public housing on the urban fringe, which has been called “the bedroom community of the working poor.” The bulk of metropolitan growth since the World War II has in fact been along the southern edge, where the Central Valley widens and land is relatively cheap. In the mid-1970s, the government bought large tracts of agricultural land and committed its housing resources in this area. The government’s “making neighborhoods healthy” (saneamiento) program has brought services such as water, sewer, and electricity to much of this housing.

A Bit of Trivia

Because Santiago is close to the west coast of South America, it might be hard to tell whether it’s east or west of Los Angeles. But it’s not even close. Santiago is almost straight south of Boston. In fact, because of the angles, the orbit path for this scene (path 233) is one path east of Newfoundland (path 1).

In the 1975 image, the initial clearing for the San Julian settlements is visible along the highway—the pink line heading north-south. Later images show a well-defined 3x3 box pattern with roads connecting them. The United States Agency for International Development (USAID) helped fund new roads along with wells and community center clearing.

In the middle of the two groupings of nucleos is a clearing of a different pattern. This is the Zapito private farm, which is not part of the San Julian colonies.

As an example of how the cities of the region have merged after the 1978 reforms, these images are a closer look at Guangzhou and Foshan. Even in 2000, they were clearly separate cities. The land between them then fills in with urbanization.

The 2017 image shows the appearance of what appear to be several black dots between the two cities. These are high-rise residential buildings. They look a little similar to the fish ponds, but these are a bit smaller, and they are dark because of the shadows they cast on the ground.

Guinea-Bissau is a small country in West Africa. Complex patterns can be seen in the shallow waters along its coastline, where silt carried by the Geba and other rivers washes out into the Atlantic Ocean.

Honduras is one of Latin America’s top producers of cultured shrimp. Since the 1980s, vast areas of land have been converted to shrimp farms around the Gulf of Fonseca along the Honduras-Nicaragua border. But there are concerns about the environmental impact of this industry on the gulf’s wetlands.

A large outbreak of gypsy moth (Lymantria dispar) caterpillars attacked the hardwood forests of the northeastern United States in 2016. A fungus (Entomophaga maimaiga) introduced from Japan has kept gypsy moth populations at relatively low levels since the late 1980s. However, abnormally low rainfall during May and June in 2014, 2015, and 2016 reduced the effectiveness of the fungus, resulting in the worst outbreak seen in New England in over 30 years.

Gypsy moth caterpillars devour the leaves of hardwood trees, causing the greatest damage in late June as the larvae reach maturity. While the gypsy moth caterpillars thrived in the 2016 drought conditions, this spring's rainfall made the fungus effective again and caused high levels of mortality. However, mortality reached a peak at the end of the larval stages, after the caterpillars had already caused most of the damage. Oak-dominated forests in Rhode Island and eastern Connecticut were hit particularly hard this year.

Valerie Pasquarella, a Postdoctoral Research Associate at the University of Massachusetts Amherst, is using Landsat data to track the spread of the outbreak and monitor defoliation. She compares newly acquired Landsat observations with long-term average conditions derived from Landsat time series to detect changes in vegetation greenness in near-real time.

Individual near-real-time assessments can also be combined to produce wall-to-wall assessments of average potential damage over the course of the growing season. In these season-integrated maps, blue indicates forest conditions that are within the normal range of variability, while yellow, orange, and red show decreases in vegetation greenness indicative of defoliation. The 2017 image is preliminary and represents an averaged view of the potential damage as of August 1.

While Landsat has not typically been used to monitor insect outbreaks in near-real time, new analytical tools along with the open access to Landsat data make it possible to quantify insect damage over a large area at a level of detail not possible with aerial surveys alone.

A new journal article describing the methods used to generate these maps is available at http://www.mdpi.com/1999-4907/8/8/275.

While certainly too small to see from space, the gypsy moth caterpillar (Lymantria dispar) can cause enough change in a forest to be seen with Landsat’s 30-m resolution. A mere 1/16 inch long when they hatch in May, the caterpillar can reach 3 inches long by late June when they pupate. In that short time span, the pest feeds on the leaves of deciduous trees. Beginning in 2016, they caused noticeable change in the Northeastern United States.

While Landsat has not typically been used to monitor insect outbreaks in near-real time, new analytical tools combined with the open access to Landsat data make it possible to quantify insect damage over a large area at a level of detail not possible with aerial surveys alone.

The 2016 and 2017 images show the widespread defoliation of the trees in orange-brown, with a large area of heavy defoliation to the west of Providence, Rhode Island, and additional patches in eastern Connecticut. In 2018, defoliation was much less widespread and severe; however, continued defoliation is now mixed with mortality as individual trees succumb to multiple years of defoliation and other stressors including drought.

These images show the location of the USGS Earth Resources Observation and Science (EROS) Center, about 10 miles north of Sioux Falls, South Dakota. On Sunday, July 13, 1997, an unusually severe hailstorm blasted through the area, missing Sioux Falls but hitting EROS head-on. The storm pounded EROS with 20 minutes of baseball- to softball-sized hail. Landsat 5 passed overhead three days later and documented the aftermath.

Healthy crops normally surround Sioux Falls. The healthy crops appear bright red because red represents the near-infrared light (that human eyes can’t see) that is highly reflected by healthy vegetation. Most of the crops grown in this area are soybeans and corn. Some of those fields turned gray in the 1997 image, where the hailstorm converted the cropland into bare soil. The conversion was temporary, however, as the Landsat 5 image from 1998 demonstrates. The cropland is back to the expected red, indicating healthy crops.

The British Antarctic Survey has studied Brunt Ice Shelf in person since 1955. Scientists at their Halley Research Station study Earth, atmospheric, and space weather processes. Since 2012, the station has been made up of eight interlinked pods, built on skis so they can be moved, such as during the Antarctic summer of 2016–2017. Referred to as Halley VI Research Station, it was moved to the eastern side of Chasm 1.

The station is constantly on the move anyway, since the floating ice shelf flows at a rate of up to 2 km per year toward the west.

Images from Europe’s Copernicus Sentinel-2 satellites show the station’s previous location in 2016 and new location after that. Even at this satellite’s 10-m resolution in natural color images, the station consists of only a few pixels.

Another rift appeared on the Brunt Ice Shelf in October 2016 and quickly extended eastward. Dubbed Halloween Crack, it’s located about 12 km north of Halley Research Station. By March 2017, the crack cut 35 km across the ice shelf. By October 2018, it was 60 km long.

These images from Landsat 8 use only its panchromatic band. The resolution of this band is 15 m, rather than the 30 m of the other bands. It makes the images grayscale, which in Antarctica is not much different from natural color.

Do you see Halley Research Station move into view in the lower right of the images?

How about another rift forming in the last images and an iceberg breaking from the shelf? More on that in the “North Rift” sections.

Sydney Harbour defines the city and makes it recognizable worldwide. Parks, reserves, and gardens line the 240 kilometers of shoreline of this beautiful natural harbour. Any green that you see in the images along the harbour are parks or reserves—along with a few golf courses.

The Sydney Harbour Bridge crosses the harbour. This well-known Australia landmark opened in 1932. The height of the top of the arch is 134 meters above sea level. The 1-kilometer-long bridge is visible in the Landsat images, but you have to look closely.

Located near the bridge is one of the world’s most recognizable buildings and part of Sydney Harbour’s landscape. The Sydney Opera House was completed in 1973. It is seen as a few bright pixels in the images, on the end of the point nearest the bridge.

The 2000 Summer Olympic Games took place in Sydney. Can you spot the location of Sydney’s Olympic Park?

Dark-colored volcanic cones sprout from an ancient lava field known as Harrat Al Birk along Saudi Arabia's Red Sea coastline. Many such lava fields dot the Arabian Peninsula and range in age from 2 million to 30 million years old.

Haruj is the large volcanic field that dominates this Landsat image mosaic acquired over central Libya. The plateau was built from basaltic lava flows that erupted over time from approximately 150 separate volcanoes. The volcanic craters and lava flows are all evidence of a previous active period, well preserved in the dry Sahara Desert.

The geologic evolution of this landscape is not fully understood, but some scientists have used the texture and color differences revealed in satellite images to try to interpret the relative ages and sequence of different volcanic events. The numerous spectral bands and band combinations available from Landsat mean that the color variation of individual lava flows can be especially helpful for interpreting different phases of volcanic activity.

Many of the bright spots within the darker colored basalt flows are sand-filled craters associated with individual volcanoes. Other light-colored areas are depressions covered with silt and fine sand.

This image mosaic consists of numerous Landsat 8 scenes acquired in early 2015. Landsat images can be useful to support geologic mapping and studies of large and remote features such as this.

Another consequence of the dam is the burial and inundation of the Hasankeyf archaeological site. The site has evidence of human habitation dating back 12,000 years.

Before the reservoir inundated the town, residents were relocated to high ground north of the river. Named New Hasankeyf, the new town is home to a few historical structures moved from their original locations, including a tomb, a mosque, and an ancient bath. While a section of the old town remains above the water, many archaeological sites were submerged beginning in 2019.

The declassified Hexagon satellite image also shows enough detail to reveal Hasankeyf’s previous location.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

The state of Hawaii consists of eight main islands: Niihau, Kauai, Oahu, Molokai, Lanai, Kahoolawe, Maui, and Hawaii. From east to west, Hawaii is the widest state in the country.

Soaring, snow-capped peaks and ridges of the eastern Himalaya Mountains create an irregular white-on-red patchwork between major rivers in southwestern China. The Himalayas are made up of three parallel mountain ranges that together extend more than 2,900 kilometers.

The Biloxi-Chitimacha-Choctaw community began in the early 1800s when Frenchman Jean Marie Naquin married Pauline Verdin, a Native American. Naquin’s family disowned him for this, and the couple moved to the delta region, where his father had traveled many times. Despite being disowned, Naquin named the island where the couple settled after his father Jean Charles Naquin.

Naquin and Verdin, along with the other original inhabitants of the island, had also moved there to escape the Trail of Tears, the forced removal of Native Americans from the southeast in the 1830s to present-day Oklahoma. They sought refuge in the dense forested swamps of the Mississippi Delta, which white settlers thought were uninhabitable.

Most of Jean Marie and Pauline’s children married descendants of the Biloxi-Chitimacha and Choctaw tribes. Other families moved to the island after intermarriage between the families. By 1910, the island population had grown to 16 families, all descendants of the first families to settle there. They lived by fishing, gathering oysters, trapping, and hunting.

By the 1950s, there were around 80 families living in Isle de Jean Charles, and the island spanned 33,000 acres. Today, the island has shrunk to 320 acres and fewer than 30 families remain. Many residents moved elsewhere, fracturing the community. With the people scattered, the heritage and traditions are fading away. Afraid of losing their culture, the community is now planning another resettlement, possibly the only way for them to adapt to the changing Louisiana coast.

The tribe has been planning resettlement since 2000, and in January 2016, the U.S. Department of Housing and Urban Development (HUD) awarded the tribe $48 million to help them move. A possible location has been chosen that would allow the community to regain their culture with traditional hunting, fishing, and agriculture. The site is a 515-acre sugar farm north of Houma. Resettlement, however, is a difficult concept to accept. Tribe members say losing the island is like losing a family member.

Moderate resolution imagery from Landsat (30 meters) and Sentinel (10 meters) shows a broad view of the changes around the island over time. Landsat’s history goes back to 1972, with 60-meter resolution imagery to show a long view of the change.

Sentinel-2A

Imagery from the Europe's Copernicus Sentinel-2 satellite is distributed by the USGS through EarthExplorer.

A volcanic eruption that started on August 31 in Iceland shows no sign of weakening. This eruption is occurring at the Bardarbunga volcano, which lies north of the Vatnajökull glacier in south-central Iceland. Lava has been flowing spectacularly from the Holuhraun lava field, and the eruptive fissure has now spread lava across more than 70 square kilometers (27 square miles).

 

These Landsat 8 images show different spectral bands and band combinations acquired on September 6, 2014. These images provide examples of the type of information being used by scientists to monitor and map the eruption.



The first image is a false-color composite that combines information from the shortwave infrared, near-infrared, and green wavelengths of light. In this image, the recently erupted lava glows bright orange and red. The areas covered by snow and ice within the neighboring glacier can also be seen in shades of blue-green. The second image is a natural color representation, based on the visible wavelengths of light. In this image, the location of active volcanic fissures can be seen as small bright features, and the plumes and trajectory of ash and steam can also be clearly seen. The surface of the cooling lava flows (where visible) are black. The third image is a thermal infrared representation. This image shows relative surface temperature over the region, with the hottest areas (erupted lava) shown in bright hues and colder areas (glacial ice and water bodies) shown in dark tones.



The combined information available in Landsat images can provide an important complement to ground sensors. These images are important for scientists and decision makers engaged in mapping and monitoring the eruption.

 

Landsat data can track the spread of the outbreak and monitor defoliation. Comparing newly acquired Landsat observations with long-term average conditions modeled from Landsat time series makes it possible to detect changes in vegetation “greenness” in near-real time.

These forest condition assessment maps represent changes in expected forest reflectance signatures compared to average patterns over an 11-year baseline. Blue pixels indicate forest conditions that are within the normal range of variability, while yellow, orange, and red show sustained decreases in vegetation greenness that coincide with caterpillar stages of the gypsy moth life cycle and are indicative of varying degrees of defoliation.

Black is non-forest, according to National Land Cover Database 2011 (NLCD 2011) classifications.

Data from Landsat not only detects initial outbreak and magnitude of the defoliation but also recovery later in the season.

The Huang He (Yellow) River in China is the most sediment-filled river on Earth. It flows from the Bayan Har Mountains to the Bohai Sea. Along the way, it crosses a soft plateau that is covered with fine, wind-blown soil. The river carries away millions of tons of this delta-building material every year. Over time, the river carries its sediment load farther outward into the sea. These Landsat images provide a view of the dramatic changes to the shoreline.



Besides changes to the delta, aquaculture has significantly expanded along the coastline near the river delta, as well as farther south along Laizhou Bay. The dark geometric shapes along the coast were built on what were once tidal flats. These ponds hold shrimp and other types of seafood.



Landsat imagery is useful in providing historical records of the changes taking place on the Earth’s surface, and future acquisitions will allow scientists to help in protecting the delta’s natural wetlands, while meeting the demands of development along the shoreline.

 

The Huang He River in China is a wanderer. Its lower reaches have changed course many times, moving the delta up and down the coast several hundred kilometers over the centuries.

The Huang He (Yellow) River is over 4,800 kilometers long. It’s the 2nd longest river in China and the 5th longest in the world. It’s also the muddiest river on Earth. On its long journey, the river crosses a soft plateau that’s covered with fine, wind-blown soil. The river carries away millions of tons of this delta-building material every year. The Huang He derives its yellow color from fine particles of mica, quartz, and feldspar.

The river shows up well in most of these Landsat images because of the high sediment load, which reflects light. The sediment even shows up in the water of many of these images where the river flows into the sea.

Unlike many glaciers in Alaska and around the world, Hubbard Glacier is thickening and advancing. Hubbard Glacier has a large accumulation area, like a river with a large watershed. This large area of snow in the mountains upstream either melts or flows down to the end of the glacier, and Hubbard steadily grows. In fact, Hubbard Glacier has advanced 1.5 miles, or about 2.4 kilometers, since 1895.

These Landsat images illustrate an unusual event that was observed twice at the terminus of Hubbard Glacier. Hubbard temporarily blocked Russell Fjord (a long, narrow inlet of the sea) from the rest of Disenchantment Bay and the Gulf of Alaska. It’s even possible that the glacier could one day permanently block the fjord.

Hurricane Florence hit the Carolina coast on September 14, 2018, but it took much longer for the full impact to emerge.

Remotely-sensed images show the slow devastation that 13 trillion gallons of rain can bring as it moves back toward the sea.

Conway, South Carolina saw some of its most severe flooding nearly two weeks after the storm hit. This Landsat 8 image from September 26 shows the Waccamaw and Little Pee Dee rivers swollen on either side of the city.

Conway’s Lake Busbee was drained to wetlands this spring, and the image from August 9 shows streaks of green vegetation feathering through it.

By September, Hurricane Florence refilled the lake. Floodwaters also created a new pond across the lake’s northeast bank in space once occupied by a power plant.

Civil Air Patrol (CAP) imagery ingested through the USGS Hazards Data Distribution System (HDDS) offers an even closer view of the area, which is near downtown Conway.

Similar troubles bedeviled other cities across the Carolinas. Georgetown, South Carolina sits at the confluence of four major rivers, and the waters crept higher as the days passed. The water drained into Winyah Bay some two weeks after the storm made landfall, leaving flooded fields and saturated soils along its path.

Goldsboro, North Carolina is about 100 miles from the Atlantic Coast. Imagery from September 18 shows the Neuse River spilling its banks to fill oxbows and overtake parts of Seymour Johnson Air Force Base.

Imagery archived at the Earth Resources Observation and Science (EROS) Center can be used to monitor disasters and recovery on a wide scale.

Extensive flooding inundated the Gulf Coast of Texas after Hurricane Harvey made landfall as a Category 4 hurricane on August 25, 2017. Among the many waterways in southeastern Texas that exceeded flood stage was the Brazos River, which flows past Houston to its west and to the Gulf of Mexico at Freeport. A USGS streamgage on the Brazos near Rosharon showed that a river level normally at around 10 feet peaked at 52.65 feet on August 29. That was about 10 feet above flood stage.

Even with scattered clouds in these Landsat images, the extent of flooding on the landscape just south of Houston is evident. The Landsat 8 image from August 12 shows the area before the storm hit. Landsat 7 passed over the same area on September 5 to show the flooded Brazos River.

Landsat continues to monitor the extent of the flooding caused by Hurricane Harvey.

Hurricane Harvey made landfall on the Gulf Coast of Texas as a Category 4 hurricane on the night of August 25, 2017. It then stalled over southeastern Texas as a tropical storm and continued to creep northeast over Louisiana.

What made Harvey an unusually devastating storm was its rain. Extraordinary rain totals were recorded at several locations. On August 30, the National Oceanic and Atmospheric Administration (NOAA) reported a rainfall total of 51.88 inches at Cedar Bayou and FM Road No. 1942, just east of Houston.

These four images show Harvey’s development over the Gulf of Mexico and its movement across Texas. The images were created using NASA-generated Surface Reflectance data products from the Visible Infrared Imaging Radiometer Suite (VIIRS), one of the instruments on the NOAA/NASA Suomi National Polar-orbiting Partnership (S-NPP) satellite. VIIRS provides daily global coverage at multiple resolutions. Land S-NPP NASA VIIRS data products are made available by the Land Processes Distributed Active Archive Center (LP DAAC) and can be accessed using NASA’s Earthdata Search or the USGS’ EarthExplorer.

Hurricane Irma was a Category 5 superstorm when it lashed the Caribbean island of Barbuda on September 6, 2017.

Irma’s eye passed directly over the small island, and wind gusts of 185 miles per hour stripped the island’s vegetation. Villages were destroyed. An estimated 95 percent of the island’s structures were damaged, including destruction of its hospital, schools, and airport. Barbuda’s 1,800 residents evacuated to Antigua.

The dramatic changes to the island caused by Irma, the strongest Atlantic hurricane on record, are shown in this pair of images from Landsat 8. Landsat uses shortwave-infrared, near-infrared, and green wavelengths to reveal those changes. The August 27 image shows healthy vegetation as bright green. In the September 12 image, that bright green appears washed out, the degraded vegetation after the storm.

Hurricane Katrina was one of the most intense and costliest hurricanes to hit the United States. On August 28, 2005, Katrina was a category 5 storm (on the Saffir-Simpson scale) in the middle of the Gulf of Mexico. It made landfall the next morning as a strong category 3 storm with sustained winds of 125 miles (200 kilometers) per hour.

Flooding in New Orleans began early that morning, and water continued pouring into the city until September 1. State health departments estimate that Hurricane Katrina caused about 2,000 deaths, most occurring in Louisiana. About 75 percent of the New Orleans metropolitan area was flooded. The storm caused an estimated $80 billion in damage.

Landsat recorded the devastation and continues to monitor the region’s wetlands. New Orleans, Louisiana, is near the bottom of the images along the Mississippi River. The city lies just south of Lake Pontchartrain. Hundreds of square miles of wetlands were lost after Katrina. Some marshlands became permanent water bodies. Some projects now aim to bring back marshlands because of their value in defending the coastline from storms.

(Black stripes run through the Sep. 15, 2005, images because of the Scan Line Corrector failure on Landsat 7 in May 2003.)

A week after Hurricane Matthew slammed through southwestern Haiti on October 4, 2016, Landsat 8’s Operational Land Imager sensor provided dramatic documentation of the scope of destruction in the Caribbean country.



In Haiti, land is often managed in small patches. A household may have subsistence crops in a number of locations, often on steep slopes. Data acquired on September 26 shows the landscape green with vegetation. On October 12, eight days after the storm, the hillsides are denuded after the Category 4 storm washed away crops and fallows.



Also evident in the post-storm image is a surge of sediment in the coastal waters at the mouth of the Ravine du Sud River near the seaport town of Les Cayes after Matthew went through. Geologists say the sediment likely comes from slopes that lacked protective tree cover.



The slow-moving storm dropped upwards of 30 inches of rain across parts of the impoverished nation. Hundreds of thousands of homes were damaged or destroyed. Meanwhile, public health authorities fear that the rush of rain will worsen a cholera epidemic that was already present.

 

Hurricane Michael made landfall in the Florida Panhandle on October 10, 2018.

Landsat 7 images captured before and after highlight the destructive path of the Category 4 storm.

Mexico Beach was all but demolished, with homes left in heaps by wind and storm surge. The green leaves that pop in the September image are stripped from trees by October, and the dull brown of debris remains.

Panama City and the surrounding areas also lost color after the storm. Aerial imagery from Civil Air Patrol shows the flattened trees responsible for the change.

The coast saw serious impacts. A strip of Crooked Island disappears beneath the water in the October image, and bright aqua streaks thread through the sand south of Tyndall Air Force Base.

Landsat can be used to track and study the impact of hurricanes and other disasters.

On October 29, 2012, Hurricane Sandy barreled across the shorelines of New Jersey, New York, and Connecticut, impacting lives across two dozen states that fell within its destructive path.

High Resolution Orthoimagery archived at the USGS EROS Center and inset into the larger image show the New Jersey coastal town of Mantoloking five years before Sandy made landfall, as well as the slow recovery three years after the storm. Entire blocks of houses visible in the 2007 image were damaged or completely washed away by the storm surge and wind, replaced by empty patches of sand in the 2015 image.

The larger background image acquired by the Remote Sensing Division of the National Oceanic and Atmospheric Administration in the days after the storm in 2012 shows the immediate devastation, including a breach cut across the island and connecting the Atlantic Ocean to Barnegat Bay.

The Mantoloking Bridge was covered in water, sand, and debris from houses after the storm. Built for roughly $25 million and opened in 2005, it was closed after Sandy went through because county officials considered it unstable, and didn’t reopen until the first week of January 2013.

 

As Hurricane Sandy made landfall on October 29, 2012, the storm’s waves and wind cut a breach in a narrow part of Fire Island, a barrier island south of Long Island, New York. Referred to as the “wilderness breach,” the new channel was cut in an area called the Otis Pike Fire Island High Dune Wilderness of the Fire Island National Seashore.

The breach grew rapidly. The year after the storm, several nor’easters widened the opening. This series of Landsat images shows Fire Island before Hurricane Sandy hit, then again after the storm. The November 6 image shows the breach starting to open, under thin cloud cover. The growing shoal area on the north side of the breach can be seen in the images after the storm.

Breaches are natural barrier island features, and they can change flooding risk to coastal communities. The Fire Island breach provided USGS scientists with an opportunity to study this natural process in depth.

Bathymetric surveys in the years after Hurricane Sandy along with satellite images help scientists model future changes of the barrier island and better predict what may happen to the region in future storms.

The Sentinel-2 satellites from the European Space Agency (ESA) use infrared imaging to highlight certain information about the land surface. In the near-infrared wavelength of light, actively growing vegetation appears red in these images that show the lake more closely at a resolution of 10 m.

The cropland appears in bright red around the lake, and the greenhouses are the light blocky shapes. However, bright red swirls also appear on the surface of the lake, and the extent and location change in each image. Sentinel’s near-infrared proves that it’s vegetation and that it’s alive.

The nuisance plant is water hyacinth, a fast-spreading, free-floating plant that forms moving, impenetrable mats. It hinders boating and fishing and interferes with the ecology of the lake.

European settlement in the early 1900s likely brought hyacinth to Lake Naivasha. Around 1920, hyacinth was tossed into the lake to beautify it. Low nutrients restricted it to the shallow northern shores for decades. It spread to other parts of the lake in the 1980s. The flower farms increased at this time, using so much water that the lake level dropped, exposing hyacinth seeds. As the lake became over-enriched with farm runoff, the hyacinth thrived.

In the Landsat images in the other sections, the near-infrared wavelength is used to make vegetation appear green. The extent and location of the hyacinth on the lake’s surface changes over the years in those images, visible as the bright green shapes on the lake.

The hyacinth was at first limited to protected bays and estuaries. The western part of the lake has been most affected recently, but these images do show it spreading over various parts of the lake. Scientists will continue to use Sentinel, Landsat, and other remote sensing instruments to track the changes caused by the blooming cut flower industry.

An aerial image from 1952 shows Lake Thompson as a wetland, with about one-third of it as open water. Landsat began observing the area in 1972 with multispectral imaging that includes visible and near-infrared bands, which are great at distinguishing open water from dry land.

Water levels have fallen somewhat since the 1990s but continue to fluctuate depending on annual precipitation. Some shoreline and shallow areas change between dry land, marshland, and open water.

Most lakes in the PPR are closed systems. That means they do not have an outlet for water to flow out. It also means they can change a lot based on variable rainfall and snowmelt from year to year. As these water bodies expand, they can connect to other water bodies that were previously disconnected.

From around the 1890s until the mid-1980s, most lakes around Lake Thompson were closed lakes, disconnected from one another. Above average precipitation in 1984 brought an increase in tributary inflow into the lakes of Kingsbury County. Above average rain continued for two more years, and a chain reaction began that went something like this: In April 1986, Spirit Lake overflowed and drained into Mud Lake. Mud Lake then overflowed, its water draining to Silver Lake by way of a drainage channel. Silver Lake then overflowed into Lake Thompson.

But that’s not all.

Lake Preston also overflowed around that time and drained into Lake Whitewood, which subsequently rose above its outlet and drained into Lake Thompson. By October 1986, Lake Thompson ceased to be a closed basin when it drained into the East Fork Vermillion River. Water from the East Fork Vermillion River subsequently flows into the Missouri River. This marked the first time Lake Thompson had overflowed in over 100 years.

The effects on the hydrology in the region where mountaintop mining takes place is not well understood—how does this mining activity affect the movement and storage of water?

The EPA, in a 2011 report, explains that stream ecosystems are affected by mountaintop mining in five principal ways:

• Springs are permanently lost when buried under valley fill.
• Elevated levels of chemicals are found downstream.
• Degraded water quality in streams can be lethal to organisms.
• Selenium levels are elevated in the water, toxic to fish and birds.
• Fish communities are degraded.

One way hydrology changes is through the reclamation process. Heavy equipment compacts the soil, which inhibits water infiltration and natural succession. That is, the compacted soil doesn’t soak in water the same way as it did before when it was natural forest. Native trees do not grow well in this compacted soil, where rainfall runs off faster. Even when grasses are planted immediately during reclamation, runoff is increased in these areas.

Increased runoff can lead to more frequent downstream flooding. Some fill areas that have large volumes of crushed rock can actually increase watershed storage. But how and to what extent these areas control runoff are not clear.

Furthermore, groundwater samples from mined areas after reclamation have been found to contain more mine-derived chemicals than water from unmined areas. These chemicals (lead, aluminum, chromium, manganese, and selenium) would otherwise remain sealed up in the coal and rock. Water flowing through the valley fills picks up these chemicals and flows into the streams. Researchers have linked declines in stream biodiversity to an increase in these contaminants, affecting the freshwater species found there.

A 1.1-mile long, 509-foot-tall concrete dam spanning the Blue Nile River is set to become the largest hydropower plant in Africa. Under construction since 2011, the Grand Ethiopian Renaissance Dam is expected to produce about 16,000 GWh of electricity annually when fully complete in 2023, providing power to 60% of Ethiopia’s estimated 115 million people.

An initial filling of the Ethiopian Reservoir can be seen in the 2017 Landsat image. The water level then dropped before the first phase of reservoir filling began in the summer of 2020. The 2021 image was acquired in April during the dry season.

The curved shape southwest of the main dam is referred to as the Saddle Dam and hints at the reservoir's eventual capacity of 74 cubic kilometers. That's about twice the volume of Lake Mead which supplies water for irrigation and human consumption in the southwestern United States.

The Mille Lacs Lake ice roads are short-lived. Ice houses need to be off the lake before the ice breaks up in the spring. The deadline varies by year, depending on ice conditions. It’s usually in late February to early March.

The number of ice houses on Mille Lacs Lake can exceed 5,500. Ice fishers are after walleye, northern pike, muskie, yellow perch, largemouth and smallmouth bass, and tullibee.

It’s possible for the roads to be obscured after a snowfall, to the extent that they need to be plowed. So some images show the roads as less clear.

The world’s longest ice road connects Yellowknife to three diamond mines: Ekati, Diavik, and Snap Lake. Of the 475 kilometers (300 miles) of ice road, 86 percent of it is across frozen lakes.

The ice road is the only overland supply route for the mines. Each winter, a year’s worth of fuel, construction material, heavy mining equipment, and explosives are trucked to the mines. The road provides the most cost-effective method for transporting these supplies.

Open only 8–10 weeks of the year, the ice road is open from mid-January to March. It has to be rebuilt each year. Work on the road starts soon after Christmas. When the ice is 1 meter (42 inches) thick, it can support a truck fully loaded with over 40 metric tons (44 tons) of fuel.

Full trucks traveling north have a strict speed limit of 25 kilometers (15.5 miles) per hour. Empty trucks heading south can use the express lane and go up to 70 kilometers (43.5 miles) per hour. The number of trucks the road handles per year varies. Just over 6,000 truckloads were driven north during the 2013 season.

This place is so far north it’s too dark for satellite imaging in the middle of winter. Early summer, late summer, and late winter images are shown for comparison. There is still some ice on the lake in the July images. In the April images, the straight dark lines across the ice are the temporary roads.

Cloud-free satellite views of Lake Saimaa in Finland are rare in January. But this Landsat 9 scene, captured on January 4th, reveals over 200 miles of winter shipping lanes. The water vapor from 3 large wood pulp factories can be seen on this shoreline. One is located in Lappeenranta, where the ice route begins.

Icebreakers in Finland often keep shipping lanes open through November and December, or until the ice is too thick to break. This route leads north, winding through the coniferous forest of Finland's “Lakeland”. Savonlinna is the home port of at least one local icebreaker, TYRSKY, which appears to be in winter layup as of January 3rd.

Icebreaking activity north along the route is still visible. Here, the route splits near Linnansaari National Park. One branch leads northwest, eventually reaching Varkaus, where another wood mill is visible. The east branch of the route continues on toward Joensuu. Here the route passes through Lake Paasselkä, a deep lake over an ancient impact crater. The frozen lane continues north. This scene ends before the ice route's destination: Joensuu, Finland, but we can see the remainder in a previous capture from 2020.

On January 20th, Landsat 9 captured a new scene, showing that the route has been frozen over until spring. The Landsat archive is used in Finland, and around the world to monitor seasonal changes like these.

Major rifts have formed near a distinctive feature called the McDonald Ice Rumples. The feature, rising about 10 m above the surrounding ice shelf, may be responsible for the relative stability of Brunt Ice Shelf over most of the 20th Century.

Ice rumples form when ice flows over a rocky formation on the seabed. As the shelf moves toward the ocean, ice collects behind the rock and wrinkles. This rocky formation impedes the flow of ice, causing pressure waves, crevasses, and rifts to form at the surface.

Through this Landsat time series, the feature that causes the rumples remains stationary, while the ice shelf and its rifts flow west.

Like distant galaxies amid clouds of interstellar dust, chunks of sea ice drift through graceful swirls of grease ice in the frigid waters of Foxe Basin near Baffin Island in the Canadian Arctic. Sea ice often begins as grease ice, a soupy slick of tiny ice crystals on the ocean's surface. As the temperature drops, grease ice thickens and coalesces into slabs of more solid ice.

 Along the southeastern coast of Greenland, an intricate network of fjords funnels glacial ice to the Atlantic Ocean. During the summer melting season, newly calved icebergs join slabs of sea ice and older, weathered bergs in an offshore slurry that the southward-flowing East Greenland Current sometimes swirls into stunning shapes. Exposed rock of mountain peaks, tinted red in this image, hints at a hidden landscape.

Around July 10–12, 2017, in the middle of the long, dark Antarctic winter, a rift in the Larsen C Ice Shelf broke through the last few miles of ice to the Weddell Sea and formed a new iceberg. The NOAA National Ice Center has given the Delaware-sized iceberg the designation A-68. Even in the darkness, Earth-observing satellites are monitoring this new iceberg with infrared imaging.

In a July 12 image, the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on NASA’s Aqua satellite shows relatively warm open water completely around the new iceberg. The crack between the iceberg and the ice shelf is really a soup of floating, broken pieces of ice on top of the water.

On the same date, the Thermal Infrared Sensor (TIRS) on Landsat 8 recorded its own image showing the relative temperature of the ice and the rift. The bright line, located at the edge of the Landsat scene, is sea water at the freezing point rather than frozen solid. Normally, Landsat acquisitions for Antarctica are suspended when the Sun gets close to the horizon around early April. A special acquisition request was made to get nighttime imagery of the Larsen C area to help track the growth of the rift as it got closer to breaking free.

Landsat and MODIS will continue to monitor the movement of the iceberg as it separates from the ice shelf and likely drifts northward along the Antarctic Peninsula. Many factors will affect the iceberg’s future motion, including wind, tide, and current, and the fact that ice on the sea next to the iceberg will inhibit it from drifting as far as it would if there were no ice. All of these factors will be visible thanks to the satellites’ thermal infrared imaging.

This stretch of Iceland's northern coast resembles a tiger's head complete with stripes of orange, black, and white. The tiger's mouth is the great Eyjafjorour, a deep fjord that juts into the mainland between steep mountains. The name means "island fjord," derived from the tiny, tear-shaped Hrisey Island near its mouth. The ice-free port city of Akureyri lies near the fjord's narrow tip, and is Iceland's second largest population center after the capital, Reykjavik.

These two Landsat images show several of Iceland’s ice caps as they appeared in September 1986 and 2014.

The largest white area is the Mýrdalsjökull Ice Cap. Underneath this massive mound of ice sits the active Katla volcano. Katla erupts every 40–80 years and is accompanied by high-volume glacial outburst floods (jökulhlaups). The smaller ice cap to the west is Eyjafjallajökull. This ice cap also covers an active volcano, which last erupted in 2010 and disrupted air travel for several weeks.

The brown areas on both ice caps consist of accumulated volcanic ash and other deposits from past volcanic eruptions. The dark cover of volcanic ash from the 2010 eruption is especially prominent on the 2014 image of Eyjafjallajökull.

At first glance, there appears to be remarkable shrinkage of the ice caps by 2014, the situation for most of Iceland’s ice cover. However, the bright white areas in the 1986 image represent fresh snow cover, which is not present in the 2014 image. To monitor the actual changes in the extent of an ice cap, scientists measure changes in the position of the terminus of outlet glaciers.

Landsat is one of several important remote sensing tools being used by glaciologists to map and monitor changes in the Earth’s ice cover over time.

Appearing as if an artist imitating Jackson Pollock had randomly spurted ink onto the canvas, this image shows swirling ice in the Foxe Basin of northern Canada. Even though the image is from late July, there was still ice floating in the water this far north.

The remnants of Hurricane Ida dumped several inches of rain on eastern Pennsylvania. Landsat images show the Schuylkill River west of Philadelphia where muddied waters rose in several communities.

The August 26th image shows typical river levels in the Phoenixville area:

On September 2nd, a USGS stream gauge in Philadelphia exceeded flood stage levels by over 5 feet. Phoenixville saw heavy flooding with water overtopping Highway 23, and the Pickering Creek Reservoir turned from blue to brown as sediment rushed in.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Idaho grows more potatoes than any other U.S. growing region, annually producing about 30 percent of U.S. fall production. Warm, sunny days, cool nights, and water from melting snow in nearby mountains make the perfect combination for growing them.

Within this scene is one of the largest waterfalls in the world. On the border between Brazil and Argentina on the Iguazú River, 275 falls collectively make up Iguazú Falls. “Devil’s Throat” is the tallest at 80 meters.

Landsat’s 30-meter resolution doesn’t reveal the falls in great detail. But in the 2011 image, a blue-white line at the location of the falls points down toward the southeast. This line is the foamy water crashing over the Devil’s Throat portion of the falls.

A runway is visible southwest of the falls. This is Cataratas Airport, which serves the city of Puerto Iguazú, Argentina, and provides access for tourists to visit the falls.

Iguazú Falls was named one of the New 7 Wonders of Nature in 2011.

Iguazú National Park is located in Argentina on the border with Brazil and Paraguay. Its boundary is sharply defined as the bright green section on the right of the images. The Brazilian side of the park, north of the Iguazú River, is called Iguaçú National Park.

The park is almost an island of southwestern Atlantic rain forest, one of the few remaining original areas of this type of tropical rain forest. The Atlantic rain forest is distinct from the Amazon and once stretched along most of Brazil’s Atlantic Coast and inland several hundred kilometers. In 1973, there were some cleared areas just north of the Iguazú River in Brazil, but they have since regrown.

These images clearly demonstrate the effect of differing land use policies surrounding the park. Paraguay lies west of the Paraná River, which runs vertically through the center of these scenes. Paraguay has permitted complete development of the land. In 1973, the area seen in these images was vegetated, but by 2011, nearly all the land on the Paraguay side appears to be under human development, with a patchwork of cleared and agricultural areas.

The deforestation in Paraguay begins with the telltale fishbone pattern. Roads built into the forest are the entryway into clearing the land for agriculture. On the Argentina side of the river, development is considerably more modest than in Paraguay. The bottom middle part of these images shows a different forest management practice. The oddly shaped patterns of deep green are forest plantations used for lumber and pulp. While intense transition from forest to agriculture can harm the land and environment, these plantations can reduce soil erosion, improve water quality, increase carbon sequestration, and provide habitat for many species.

On the border between Brazil, Paraguay, and Argentina are some curious land use features. Paraguay lies west of the Paraná River, which runs north to south down the middle of the images. The Iguazú River flows toward the west and into the Paraná River. North of the Iguazú River is Brazil, and Argentina is to its south.

At this location, we can see the effects of deforestation of the rain forest, one of the largest dams in the world, a spectacular set of waterfalls, and a sharp contrast between protected land and intense development.

For centuries, people living in what is now the Netherlands have used various strategies to control the water levels in this low-lying country. The alteration of this landscape continues as residents work to improve farmland and protect inhabited areas from flooding.

Beginning in 1932, Dutch engineers created a series of dikes to drain water from an inlet of the North Sea. The reclaimed land increased the land area of the Netherlands that could be used for agriculture.

These images illustrate the progress of the Netherlands' diking and draining of the IJsselmeer region. The IJsselmeer is a lake on the coast of the Netherlands. (This lake, or meer, is named after the IJssel River and is pronounced EYE-ssel-mare.) In the satellite images, water appears blue-black, and vegetation appears red. Highly reflective areas like pavement or bare soil appear light blue or blue-green. Amsterdam can be seen in the lower left of the images.

Until 1932, this area was the Zuiderzee (pronounced ZIGH-dr-zee and meaning Southern Sea), simply a saltwater inlet of the North Sea. By 1968, the Dutch had transformed 1,979 km² of the Zuiderzee into blocks of usable land, called polders. Here is how that typically happened:

• In 1932, the Dutch completed a dike across the mouth of the Zuiderzee, creating the IJsselmeer. This dike can be seen in the upper middle portion of these main images. The freshwater from the IJssel River flushed out the saltwater, creating a lake.
• Between 1930 and 1968, dikes were built around five portions of the IJsselmeer.
• The polders were drained using pumps.
• Reeds naturally grew on the former sea bottom. To help dry out the soil, the Dutch let the reeds grow. Transpiration moves water into the air faster than evaporation alone would.
• When the soil dried, the reeds were cleared and colza was planted. Colza is related to cabbage and turnips.
• The colza was cleared, and grain crops were planted.
• The polders were cultivated for up to five years before the land was ready to produce commercially.
• Land was then leased to commercial farmers, or towns were built.

The first of the five polders (Wieringermeer, in the northwest) was actually diked directly from the sea, not from the IJsselmeer. It was dry two years before the mouth of the Zuiderzee was closed off.

The Ilisu Dam is 440 feet high and a mile wide. Generating 1,200 megawatts of electricity, it’s Turkey’s fourth largest dam in terms of power generation.

The decline in water flow for the Tigris River can lower the water quality downstream, especially during a drought. Where the Tigris drains into the Persian Gulf in southern Iraq, the lower flow can cause saltwater intrusion from the Gulf. This hinders the recovery of the Mesopotamian Marshes.

Declassified satellite imagery reveals a now-inundated village, Koctepe, just above the location of the Ilisu Dam. The Hexagon satellite image has a resolution of 2–4 feet, enough detail to see the small village by the Tigris River.

The Tigris and Euphrates Rivers flow into the historical cradle of civilization. Dams built on these rivers in recent decades have altered the landscape with large reservoirs easily seen in Landsat imagery.

Turkey has built 22 dams as part of its Southeastern Anatolia Project, as the country works toward energy independence. The country’s last major dam planned for the Tigris is also its largest. A reservoir began filling behind the Ilisu Dam in July 2019.

Over its five decades, the Landsat program has provided a record of both natural and human-caused landscape change.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Before Abraham Lincoln was elected President, he served in the Illinois legislature and practiced law in Springfield. Lincoln is buried just outside Springfield at the Lincoln Tomb State Historic Site.

These three Landsat 5 images show several rivers in southern Illinois and Indiana, USA, during normal and flooded conditions. Peak flooding was observed in this area on June 10 and 11, 2008. The clear Landsat scene from June 11, 2008, and the clear image of “normal” conditions from June 9, 2007, allow us to compare the scenes and see exactly what damage a flood of this magnitude can cause.

Rainfall amounts ranging from about 2 inches to more than 10 inches fell in this area on June 6–7, 2008. Spring was wetter than normal, so the heavy rain easily saturated the ground. The rivers quickly rose to exceed flood stage.

Satellite images can help authorities respond to disasters such as floods. The images can help local authorities see the amount of flooding and where there is damage to property. The extent of the flood can be mapped so that response teams can view where they are needed and respond quickly.

An atmospheric river swept through southern British Columbia on Canada's western edge, November 14, 2021. Parts of the province recorded nearly seven inches of rain in that 24 hour period. One week later, sediment carried by the Fraser River is visible in the Strait of Georgia. East of the strait near Abbotsford, the scene is even more dramatic. Landsat imagery shows more than 10 square miles of flooded farm ground.

Lake Powell on the border of Utah and Arizona supplies water to millions across the southwestern United States. Long-term dry conditions put the reservoir at a historic low in 2021. Landsat 8 imagery from 2017 shows the water's elevation at 3,628 feet. The reservoir on that day was at 60.3% of full capacity. 4 years later the level is 84 feet lower, with capacity down to 29.5%. Landsat will continue to monitor the reservoir from above.

Tin Bider is an ancient and eroded meteor crater on the Tin Rhert Plateau in the Algerian Sahara. Tin Bider is nearly 6 kilometers (3.7 miles) in diameter and was caused by a meteorite impact in this region of northern Africa roughly 70 million years ago. The other streaks near the crater are unrelated to the impact event. These rock folds are geologic features older than the crater.

These images show the Imperial Valley, on the border of California and Mexico. The international border is plain in the images because of the different intensity of vegetation, shown in bright green. These images also show the Salton Sea and the growing cities of El Centro, Calexico, and Mexicali.

This valley, also known as the Salton Sink, the Salton Basin, and the Salton Trough, is actually an extension of the Gulf of California, cut off from the Gulf by the Colorado River’s delta fan. The valley was renamed Imperial by turn-of-the-century land investors. The area south of the U.S.-Mexico border is known as the Mexicali Valley.

At the bottom of the sink lies the Salton Sea, the largest lake in California. It lacks an outlet to the ocean and lies 70 m below sea level. About 85% of the sea’s inflows come from agricultural runoff, and its waters are 37% saltier than the Pacific Ocean.

NLCD images of western Las Vegas show that much more urban expansion took place here between 2001 and 2006 than over the next 5 years. The land cover classes that expand noticeably in these images are the developed classes. With these classes, NLCD can be used to track changes to impervious surface.

Impervious surfaces include roads, buildings, and parking lots—surfaces that do not allow rainwater to soak into the ground. The extent and density of impervious surface can affect water quality and flooding severity in urban areas.

In a forested area, for example, most rainfall soaks into the soils and is stored as groundwater, slowing the discharge into streams. Flooding in these areas is less significant. In urban areas, however, much more water runs off into streams quickly and increases the likelihood of severe flooding.

Studying impervious surface change allows scientists to quantify the extent of developed land cover regionally and nationally. NLCD is widely used to evaluate effects on hydrological and ecological systems in many urban areas.

Impervious surfaces are best measured with satellites. They cannot be easily or cost-effectively measured on the ground.

Scientists studying the effects of urban growth are concerned with surface imperviousness—the amount of land covered by human-made features such as asphalt, concrete, and rooftops. These surfaces are impervious to rainwater. On these surfaces, rainfall does not soak into the land; instead, it runs down the streets or across parking lots, often pooling up in low-lying areas, increasing the risk of local flooding.

During heavy rainfall, areas of increased impervious surface can be more vulnerable to flash floods. The excess water flows directly to streams, often by way of storm water drains. This directly increases streamflow and reduces the amount of water that infiltrates into the ground.

In these images, Pune itself is at the bottom right at the sharp bend of the Mula-Mutha River. Toward the top center of these images is Pimpri-Chinchwad. The pink, maroon, and lavender tones are the colors associated with impervious surfaces. In many areas, urban areas are expanding over what was once either agriculture or bare ground, visibly increasing impervious surface.

Even at Landsat’s 30-m resolution, roads and structures can be seen to increase across the landscape. Some individual buildings can be seen, too—the bright rectangles to the north. Green rectangles are farm fields in the center of the images. Over time, many of them convert to built-up impervious surface.

Scientists use hydrological models to quantify how streamflow changes in areas of increased urban growth. They can better understand how the entire watershed is changing due to urbanization. In the Mula-Mutha subwatershed where Pune is, average streamflow increased from 179.14 m³/s to 185.23 m³/s between 1980 and 2009.

Landsat data can be used to map impervious surfaces and quantify the effect of the increased runoff it causes. Landsat can also be used with the European Space Agency’s Sentinel-2 satellites to get more frequent coverage of study areas.

To extract oil that is too deep for surface mining operations, in situ mining, or “in place” mining, is used. Mining companies use steam and gravity to bring the sticky oil to the surface. This method is used where the oil sand layer is deeper than 75 meters (246 feet).

Two parallel L-shaped wells reach into the deep oil sand deposit. One injects steam through holes in the pipe. This warms the oil and lowers its viscosity. The oil then flows down to the well below where it’s pumped to the surface.

This method is not as visible in the Landsat images as the surface mining is. Each well needs a “well pad,” a small area of boreal forest cleared. A growing number of small dots appear in a grid pattern over the time series images. A vertical line appears near the top of the 2009 image. This airport was built to fly in workers close to the mining sites.

Again, an image from Europe's Copernicus Sentinel-2 satellite from 2022, shows the area in slightly finer detail at 20-meter resolution. The dots that represent well sites appear a little sharper in this view.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

More major highways intersect in Indiana than in any other state, therefore, it is known as “The Crossroads of America.” Indiana also has more miles of Interstate Highway per square mile than any other state.

The Staten Island Industrial Park in New York is now home to warehouse and distribution centers for companies like Amazon and IKEA, seen here in imagery from Europe's Copernicus Sentinel-2 satellite. But aerial imagery from 1995 shows large oil storage tanks in the same location.

The observed changes in this industrial zone highlight an interesting evolution from an economy powered by fossil fuels, to one equally dependent on electronic commerce and retail distribution. By 2006, some of the tanks had been removed. The space transformed slowly in the years that followed with a 975,000 square foot warehouse nearing completion in 2017. Additional buildings were finished shortly after including an 850,000 square foot fulfillment center now used by the online retailer, Amazon. 

Imagery archived by the USGS Earth Resources Observation and Science Center is offered free of charge, and is used worldwide to track changes through time.

The Dead Sea has no outlet. The only way water exits the sea is by evaporation. When the water evaporates, it leaves behind dissolved minerals, making the water even saltier.

Those minerals produce the basis for a valuable potash industry. Companies from both Israel and Jordan extract this raw material for fertilizer from the evaporation ponds in the southern basin. The industries that produce the potash pump water from the Dead Sea into these evaporation ponds. Potash is gathered by moving water from one evaporation pond to another.

Current studies suggest that as Dead Sea water use continues, sea levels could decline to 100 meters below the 1960s level by 2050. It would then become too expensive to pump water into the evaporation ponds.

Other uses of Dead Sea salt include

• skin products
• cosmetics
• bath salts
• water conditioning
• road de-icing

Normally, political boundaries are not visible from space. But in this series of Landsat images, we do see a political feature. The curved line in the southern basin is the border between Israel to the west and Jordan to the east.

The PRD was mostly rural before the 1978 reforms began. The major industries were farming and aquaculture. The major crops were rice, sugar cane, peanuts, soybeans, bananas, and oranges. Fish were raised in a huge system of artificial ponds.

The region’s economic growth is now outpacing the rest of the country. The relatively small farming and fishing villages have become large metropolitan areas. The PRD is a major center for telecommunications, biomedicine, robotics, genomics, and manufacturing of electronics, household appliances, computer equipment, toys, garments, footwear, plastic products, and ceramics.

The dark green areas in between cities seen in these images are the region’s dike-pond system. These artificial wetlands have been there since the Tang Dynasty, over a thousand years ago. Grass carp are grown for food in the ponds. Vegetables, sugar cane, and other plants are grown on the dikes. Mulberry trees are also grown on the dikes, and the leaves are used to feed silkworms.

In this area south of Foshan, the dike-ponds are diminishing. The vast increase in manufacturing puts pollutants into the delta, reducing the amount of fish produced. Additionally, infrastructure is built on land that once had fertile soils and fish ponds. However, the dike-ponds are also extending toward the south and east, replacing farmland. Their extent now covers a wider range and is increasingly fragmented.

In natural color satellite images of wildfires, smoke often obscures the view of the ground. Landsat uses several infrared wavelengths, or bands, of light. If some of those infrared wavelengths are used, then different details about the location of burned areas emerge.

The combination of bands we have been looking at use two infrared wavelengths along with one visible band (green). This combination shows freshly burned areas as deep red and vegetation as green. Smoke from fire appears blue. The infrared bands help us see the burned areas clearly, but the smoke can still get in the way.

The third image at the left uses Landsat’s thermal infrared band and a shortwave infrared band to cut through the smoke to see ground conditions. In this false color image, burned areas are red-orange. This view can help people see where fire might be approaching populated areas.

Like blue ink bleeding onto parchment, the Khor Kalmat lagoon branches off the Arabian Sea and spills into the southern Pakistan landscape near the Makran Coast Range. Mudflats cover almost the entire lagoon, which fills with shallow water at high tides. The small areas of green are isolated pockets of mangrove forest.

On the edge of the Sahara Desert lies one of the world’s most productive wetlands. The Inland Delta of the Niger River in Mali is a vast expanse of lakes, channels, and marshes. The Niger River divides into countless channels and forms the largest wetland in Western Africa. The river and wetland form an important water resource for Mali, a landlocked and generally dry country.

This delta floods seasonally from September to December, as rainfall from the river’s headwaters in the Guinea Highlands reaches the delta’s vast flat floodplain. The southern part of the delta is low-lying floodplain with expanses of wetland grasses and reeds. The northern part has sand ridges that emerge from the water during the flood season. The seasonal flooding supports fisheries, pasture, and rice farming. Over 1 million people depend on resources in the delta.

A more up-close look in the Landsat images helps you to see the progression of clearcutting and regrowth. The colors in most of these images are a patchwork of tan, white, and various shades of green. First, notice that the landscape changes a lot during this time. How can you ensure that this series of close-up images is the same exact area? Identify features that do not change throughout the series, such as a river, as you click through the time series.

Next, notice the difference between the shades of light green and dark green. How would these two areas look if you were standing on the ground? Dark green indicates taller trees and an older forest. Light green areas are only beginning to recover from past logging, so the young trees in these areas are not very tall yet.

The tan areas are fresh clearcuts. Using the infrared wavelengths of light that Landsat can detect helps to more clearly see those cleared areas. Compare the amount of tan seen in these images throughout the time series. Can you tell how long it takes for these cleared areas to look as they did before the clearing took place?

Remote sensing means observing something from a distance. Satellites observe the Earth from space and help scientists study large tracts of land and how that land changes over time.

The sensors onboard the Landsat satellites use reflected light to detect electromagnetic energy on the Earth’s surface. The level of energy is represented by the electromagnetic spectrum, which is the range of energy that comes from the Sun. The light from the Sun that we can see is only a small part of the electromagnetic spectrum and includes the colors of the rainbow. Satellite sensors record this information in different portions of the electromagnetic spectrum, which is measured in wavelengths. Landsat satellite sensors detect both visible and infrared light.

When satellite images are made, these “invisible” types of light are assigned visible colors to represent them so that our eyes can see the data.

Shaded Relief Images of specific areas (generally by state) have been selected from the National Elevation Dataset. For original data details, see NED.

Iowa gets its name from an Indian word meaning “land between two rivers.” It is the only state whose east and west borders are entirely formed by water: the Missouri and Mississippi Rivers.

The punishing derecho storm that struck the Midwest in early August had an immediate impact on Iowa's farm fields. But it took weeks for the long term damage to appear in satellite imagery. Landsat 8 passed over central Iowa just one day after 100 mile per hour winds pummeled fields of corn and soybeans leaving thousands without power. The lighter shades of green in  the natural color August 11th image signal flattened crops still green with life. Sixteen days later the lighter areas from August 11th appear brown and tan, suggesting more permanent crop damage.

Landsat data can also be used to calculate a  Normalized Difference Vegetation Index, or NDVI, which is an indicator of  plant health. In the NDVI images, darker greens show healthier vegetation. A closer look at the fields north of Ames, Iowa shows a significant drop-off in NDVI between August 11th and August 27th.

Iowa's State Climatologist estimated that the storm damaged 3.6 million acres of corn, and 2.5 million acres of soybeans in the state.

In an area north of the city of Al-Basrah, Iraq, which borders Iran, a former wetland has been drained and walled off. Now littered with minefields and gun emplacements, it is a staging area for military exercises.

Hurricane Irma crossed the Florida Keys the morning of September 10, 2017, as a Category 4 hurricane with winds of 130 miles per hour. Besides damage done to structures on the islands, the storm also stirred the waters.

A natural color Landsat image acquired four days after the storm contrasts with an image acquired in March. The murky green-blue color is near-surface sediment churned up by strong winds. Landsat’s green band penetrates the shallow water to reveal the extent of sediment.

The distinct line south of the Keys where the sediment ends is a steep drop-off, the edge of the continental shelf on which the Keys sit. The dark color indicates deeper water compared to the shallower water of the shelf.

In the close-up image from March, a wave pattern emerges near Marquesas Keys. These aren’t water waves but sand ripples seen just under the clear water. After the storm, those ripples are obscured by suspended sediment in the turbid water.

Minor hurricanes may enhance biodiversity by clearing the reef of dead organisms. Major hurricanes like Irma, however, can damage the marine habitat. The Florida Keys National Marine Sanctuary is still assessing any damage that might have been done to marine habitats, and future Landsat acquisitions will be useful in monitoring the changes that occurred.

The economic viability of this huge project has been unclear. It’s impossible to say exactly how much the Toshka Project has cost so far—estimates of the project’s final cost range up to $70 billion USD.

If more water were to be pumped from Lake Nasser to irrigate hundereds of thousands of hectares of farmland outside the Nile basin, the lake may spill into the Toshka lakes only when there is flooding rains upstream. That's what happened in late 2019. The animation below uses images from Landsat 8 and Sentinel-2 to show the eastern lake filling to capacity—and more—starting in early October.

Will people find enough incentive to move to the area and develop it into a “New Nile Valley”? Landsat will continue to track the status of the Toshka region and its agricultural development.

There has been irrigation along the Senegal River in the Richard Toll, Senegal, area since the 1940s. With little dissolved salt, the quality of water in the Senegal River is generally good for irrigation. However, proper drainage and cropping schedules are needed to keep levels of alkaline content from accumulating in the root zone.

In the images, the many bright red fields are mostly sugarcane and rice, and virtually all of them are irrigated. The amount of irrigated land increased greatly in this time frame, and new irrigation canals are visible. The irrigated crops are able to grow in the dry season because they are not dependent on rainfall.

On the Mauritania side of the river, growth in agriculture is limited by poor soil quality and lack of agricultural education. Most of the country's food is imported. Since almost half of Mauritania's population lives at or below the national poverty level, the imported food is not always affordable. In 2007, the people's distress was expressed by food riots.

In the 2011–2012 growing season, the Mauritanian government began some new strategies to increase the yield and amount of crops grown. By training young farmers about agriculture, investing money into more irrigation, and introducing genetically modified crops that can survive in Mauritanian conditions, leaders of the country are hopeful that better times are to come for farming.

This natural landscape might appear more like a medical illustration of itchy nerve endings. In Western Sahara, Africa, an intense network of wadis drains toward the west, eventually reaching the Atlantic Ocean. These drainage courses are almost always dry in this remote part of the Sahara Desert.

This series of images of southwestern Japan shows how one change can have far-reaching consequences.

The Ariake Sea is an important fishery and resource for cultured nori (seaweed). The controversial Isahaya Bay Reclamation Project has been blamed for recent reduced harvests of fish and nori in the sea. A dike across Isahaya Bay, which was built to create more farmland, has reduced the tidal current mixing of the sea. These weaker tidal currents have led to abrupt changes in the marine environment.

The 7-kilometer sea wall (dike) was completed in April 1997, cutting off Isahaya Bay from the waters of the Ariake Sea. It separated thousands of hectares of tidal flats from the Ariake Sea and turned what was once Japan’s largest area of tidal lands into 1,500 hectares of farmland.

In the Landsat series of images, the Ariake Sea is the large body of water, and Isahaya Bay lies to its west. The dike can be seen as the straight line in the 2003 and later images, separating dark blue from light blue colored water. Black or very dark blue indicates deep water, and light blue represents shallow water. Forested areas are green, and urban areas are pink. Cropland is distinguished by its rectangular pattern: green shapes are fields with crops, and pink shapes are fields with no crops growing at the time of the image.

During the last ice age, Akimiski Island in Canada's James Bay lay beneath vast glaciers that pressed down with immense force. As the climate changed and the ice retreated, Akimiski began a gradual rebound. The island's slow but steady increase in elevation is recorded along its naturally terraced edges where the coastline seems etched with bathtub rings, the result of the rising landmass and wave action at previous sea levels.

An undersea volcano between the two small islands of Hunga Tonga (right) and Hunga Ha’apai (left) began erupting in early December 2014. After about a month of eruptive activity, a new landmass had formed, nearly joining the two islands.

This series of Landsat 8 images shows the two islands in October 2014 (before eruptions), in December 2014 (during the eruptions), and in July 2015 (after the eruptions).

Along with creating new landmass, the volcanic activity has also radically changed the islands’ ecology. The first panel shows vegetation cover (green) on both of the original islands.  The predominantly gray and brown colors in the third image now indicate bare land surface, especially on the southeastern island.  

Landsat images are often useful for mapping changes to the Earth’s land surface. Future images will also allow scientists to monitor any changes and long-term recovery of vegetation and land cover

 

The name Aral means Island. The sea did once have many islands. However, many of them stopped beings islands as the sea dried up. Two of the prominent islands were Vozrozhdeniya and Barsa-Kelmes. Throughout the series of images, they first become larger, then they become peninsulas. They are now fully connected with the mainland.

Vozrozhdeniya Island became infamous as the location of the Soviet Union’s secret biological weapons program. In the 1950s, Vozrozhdeniya was a small, isolated island in the middle of the sea. Until the collapse of the Soviet Union in 1991, various pathogens were tested, modified, and possibly weaponized on this island.

Vozrozhdeniya Island grew in size and joined the mainland around 2001. As the remote site became accessible, there was concern that the pathogens might have survived and spread to the mainland. In the early 2000s, experts from the United States helped Uzbekistan decontaminate the former island.

The former island Barsa-Kelmes is a nature reserve, established in 1939. Its natural isolation gave it great protection. But in 1999, the island became accessible, possibly threatening its pristine nature. It is now a desolate plateau, more vegetated than the surrounding dried sea bottom. However, this vegetation degraded as the sea disappeared.

For more information, see the book by Micklin and others, listed in the References section, pages 4 and 22.

Is Louisiana falling into the sea, or is the sea inundating Louisiana? It’s actually a bit of both. To the inhabitants of a tiny island on the bayou, an island getting tinier by the day, it hardly matters. They just know their home is gradually becoming uninhabitable.

A USGS report estimates that Louisiana, which experiences more coastal wetland loss than all other states in the conterminous United States combined, lost 5,197 square kilometers (2,006 square miles) of land from 1932 to 2016.

A combination of factors is causing this coastal land loss. Marshland, which historically served as protection against storms, has been carved up for oil and gas production activities. The marshland is then open to saltwater intrusion. The low elevation of the region makes it especially vulnerable to sea level rise.

These factors have an immediate effect on the Biloxi-Chitimacha-Choctaw community on Isle de Jean Charles, about 75 miles south of New Orleans. The island has lost 98 percent of its landmass since the 1950s. Once 5 miles wide and filled with lush cypress groves and cow pastures, barely a half-square mile of the island remains above water.

A variety of images created from data archived at the USGS EROS Center shows how the island and the surrounding delta have changed. Landsat’s 30-meter resolution shows the land loss to the wider delta region over time. Complementing those images are a high-resolution aerial photo from 1963 and a Sentinel-2A image, which shows much more open water in 2017. In the aerial image, open water is the darkest gray and black tones, but in the Sentinel-2A image, open water, represented by blue-gray tones, encroaches on the small island.

Is Louisiana falling into the sea, or is the sea inundating Louisiana? It’s actually a bit of both. And to the inhabitants of a tiny island on the bayou, an island getting tinier by the day, it hardly matters. They just know their home is gradually becoming uninhabitable.

A USGS report estimates that Louisiana, which experiences more coastal wetland loss than all other states in the conterminous United States combined, lost 5,197 square kilometers (2,006 square miles) of land from 1932 to 2016. Places are actually being removed from maps—NOAA is deleting labels from its maps for bays, islands, streams, and other features that are now underwater.

A combination of factors is causing this coastal land loss. Marshland, which historically served as protection against storms, has been carved up for oil and gas production activities. The marshland is then open to saltwater intrusion. The low elevation of the region makes it especially vulnerable to sea level rise.

These factors have an immediate effect on the Biloxi-Chitimacha-Choctaw community on Isle de Jean Charles, about 75 miles south of New Orleans. The island has lost 98% of its landmass since the 1950s. Once 5 miles wide and filled with lush cypress groves and cow pastures, barely a half square mile of the island remains above water.

The saltwater intrusion and loss of land have made it impossible for residents to continue the tradition of growing their own produce. They can no longer grow their own herbs for medicine. The increased cost of living from having to shop for food they once provided for themselves is a struggle.

A variety of images from the EROS archive shows how the island, and the surrounding delta, has changed. A combination of different types of imagery is needed in this location to accurately track the changes over time. High resolution is needed to see the small island, but a frequent repeat cycle reveals the larger changes taking place across the delta.

The southern tip of Spitsbergen is called Sørkapp Land. Hornsund Fjord nearly divides Spitsbergen and Sørkapp Land into separate islands. Only an isthmus of ice separates the two. The narrowing isthmus could someday make Sørkapp Land a new island.

In fact, new islands have formed in other locations on the Arctic coasts of Europe and Greenland. In places where the bedrock is below sea level, sea water inundates the space left by retreating glaciers.

The isthmus between Spitsbergen and Sørkapp Land is rapidly thinning and recessing. In 1899–1900, the isthmus was 28 kilometers wide. According to one source, the isthmus was 6.2 kilometers wide as of 2013. Based on the 2019 Landsat image, and measuring the width of the isthmus using geospatial software, the isthmus has narrowed further to about 5 kilometers wide. This ice is grounded well below sea level, so when the ice melts, there will be a strait of open water between the two lands.

The same source estimates that the glaciers on the isthmus will retreat enough to make Sørkapp Land an island by 2030–2035. The isthmus decreased from 12.3 kilometers in 1990 to 6.2 kilometers in 2013, with a rate of decrease of about 270 meters per year. This annual decrease is close to matching that 5-kilometer measurement for 2019; in fact, the decrease is slightly faster than the source’s estimate.

With the launch of Landsat 9 expected in 2021, Landsat satellites will continue monitoring the progress of these glaciers to see whether Sørkapp Land does indeed become a new island in the Svalbard archipelago.

The world’s largest hydroelectric power plant is on the Paraná River between Paraguay and Brazil. The Itaipú Dam is capable of producing 14,000 megawatts of power. The reservoir behind the dam formed in 1982 and covers 1,350 square kilometers.

The entire dam is nearly 8 kilometers long. The maximum discharge capacity of the spillway is 62,200 cubic meters per second, 40 times the mean discharge of Iguazú Falls.

Just below the dam is the rapidly expanding city of Ciudad del Este. Its estimated population in 2015 was 317,525.

A decade of drought in California has eased after the first month of 2017 thanks to heavy rains and snow, a fact that Landsat images are helping to confirm.



For the first time in three years, the U.S. Drought Monitor reported in late January 2017 that not a single area in California is considered in “exceptional drought,” the most severe category. A year ago, about 40 percent of the state was under the most severe designation. Landsat 8’s Operational Land Imager captures the dramatic reversal in these false-color views of Lake Nacimiento and Lake San Antonio along the coast in central California between Los Angeles and San Francisco.



Drought left Lake Nacimiento at only 22 percent full as of late 2016. Since 2014, Lake San Antonio had been emptied to critical levels to help recharge the groundwater in the Salinas Valley. At only 3 percent full, the lake was closed to public use on July 1, 2015. The red burn scar from the Chimney Fire in August 2016 is a vivid reminder of the drought’s impact on the area.



Today, however, the January 30, 2017, image shows how the recent precipitation has transformed the water levels in these two lakes. Lake Nacimiento is now at 81 percent full, while Lake San Antonio—virtually dry before—sits at 26 percent full.



All told, more than 48 percent of California was drought free as of February 1, 2017, compared to only 5 percent a year ago, according to the Drought Monitor.

Fed by multiple waterways, Brazil's Negro River is the Amazon River's largest tributary. The mosaic of partially-submerged islands visible in the channel disappears when rainy season downpours raise the water level.

Joe Pool Lake, southwest of Dallas, is not present in the 1974 image and shows up in the 1989 image. Impoundment of the lake began in 1986 and opened for fishing and recreation in 1989.

Because of the global trend in retreating glaciers since the start of the 20th century, proglacial lake formation has increased. Proglacial lakes are water bodies at the edge of a glacier and form during glacial retreat. Jökulsárlón Lake is an example of this process.

Also called Jökulsárlón Lagoon, this tidal inlet was excavated during the last glacial advance, which was about 26,500 years ago. Because of the glacial retreat, the lagoon is expanding at about 0.5 square kilometers per year. By 2014, the lagoon covered about 25.4 square kilometers (9.8 square miles), about the size of Block Island, off the coast of Rhode Island.

Jökulsárlón Lagoon connects to the Atlantic Ocean by way of a 100-meter wide and 20-meter deep engineered channel. Because it is connected to the ocean, tides affect the lagoon level. Water flows in at high tides. Its daily tidal range is about 2–3 meters. During summer, meltwater from the glacier increases, bringing freshwater into the lagoon, but this freshwater does not entirely flush the seawater out.

The bright specs in the Landsat images are icebergs in the lagoon that broke off the end of the glacier. Sailing among these icebergs is one of the most popular tourist attractions in Iceland.

Because 10 percent of Earth’s land surface is covered by glaciers, monitoring changes to glaciers and proglacial lakes is important to predicting the impacts of glacial thinning and retreating. These studies help develop sustainable ways of living with anticipated changes.