Views of the News
September 23, 2014 - Detailed Elevation Data-Niger River Delta
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.
September 5, 2014 - Eruption of Mount Tavurvur
Volcanic cones and settlements mingle along the margins of the Rabaul Caldera on the northeastern tip of Papua New Guinea’s New Britain Island. Shaped like a giant cauldron, the caldera is the remaining rim of an ancient volcano. The town of Rabaul sits inside the Rabaul caldera, along the edge of a spectacular natural harbor. Eruptions from nearby Mount Tavurvur continue to happen every few years. The latest occurred on August 29, 2014, when the stratovolcano spread ash throughout the area. The two Landsat 8 images above show the area before and after the eruption. In the later image, forests unaffected by ash are green, while ash-covered forests are gray. Read the full story here.
August 28, 2014 - Oil Boom—Tioga, ND
The Landsat images above show the area around Tioga, in northwestern North Dakota. Tioga sits on the Bakken Formation, which is one of the largest contiguous deposits of oil and natural gas in the United States. The bright dots in the images indicate the locations of oil wells. The 2014 image reveals the number of oil wells is increasing dramatically. Future Landsat images will provide more views of this changing landscape.
August 7, 2014 - Lake Erie Algae Bloom
Algae blooms commonly happen in late 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. No algae are visible in the June 14 image, but the algae show 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. Read more about the algae bloom at NASA Earth Observatory.
July 22, 2014 - Wildfires in Oregon
Dry conditions have made 2014 another busy year for wildfires in the western United States. Lightning started separate fires near Malheur Lake in east-central Oregon on July 14, 2014. These Landsat images were acquired on July 1, 2014, before the fires began and again on July 17, 2014, three days after the fires started. Bright orange shows where the fires were burning at the time of the July 17 image.
July 10, 2014 - World Cup: Rio de Janeiro
The 2014 Fédération Internationale de Football Association (FIFA) World Cup championship match is Sunday, July 13, at the Maracanã Stadium in Rio de Janeiro. In this Landsat 7 image, acquired on June 26, 2014, the green forested mountains contrast the gray urban area of Rio de Janeiro. Rio’s popular beaches that line the coast are visible as tan strips. The stadium where the action takes place on Sunday is visible as a white circle.
June 27, 2014 - Flooding in Southeastern South Dakota
During June 2014, more than 13 inches of rain fell over southeastern South Dakota, southwestern Minnesota and northeast Iowa. The excessive rains caused rivers and streams to overflow; flooded fields; made roadways impassible; and damaged homes and businesses.
These images, collected by Landsat 7 and Landsat 8, show the area of southeastern South Dakota on May 28, 2014, and again on June 21, 2014. Both the Vermillion River (smaller river near center), and the Big Sioux River (on the right) flooded their banks.
June 20, 2014 - Fire at Iraq Oil Refinery
A Landsat 8 image from June 18 shows a plume of smoke billowing from a large oil refinery in Baiji, Iraq. Located about 130 miles north of Baghdad, the Baiji plant is Iraq’s largest oil refinery, providing much of the region’s fuel for electricity and transportation. An attack on the refinery started late on June 17 by the allies of the extremist group Islamic State of Iraq and Syria (ISIS).
May 23, 2014 - Fires in California, USA
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. The May 9, 2014, Landsat 8 image shows the area before the fires began. In the Landsat 7 image acquired eight days later on May 17, 2014, the numerous burn areas appear as red tones.
For more information about these fires, go to the EROS Image Gallery at http://eros.usgs.gov/imagegallery/image-week-2.
April 2, 2014 - Urban expansion in Cairo, Egypt
Cairo, the capital city of Egypt, located in northeastern Africa, has expanded dramatically in the past 28 years. In the Landsat images above, the contrast between the lush vegetation of irrigated fields (bright green) and the desert (tan) is very clear. Cairo, shown as the large gray expanse, increased in population from an estimated 6 million in 1986 to over 15 million in 2014. Urbanization into the neighboring desert is also noticeable by the increased size of the smaller urban areas surrounding the city.