March 22, 2016 - Alaska Earthquake Anniversary
On March 27, 52 years ago, the largest earthquake in U.S. history struck Alaska. Tsunamis and landslides swept Anchorage neighborhoods into Cook Inlet. Aerial photographs captured the quake’s dramatic impact. 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. See the USGS EarthExplorer Web site for millions more aerial photographs in the EROS Center archive.
February 25, 2016 - Accounting for the clouds
With its third-year anniversary in flight this February, Landsat 8 continues to prove its worth in treating the satellite-imaging headache that is clouds. Landsat’s newest satellite contains a spectral band on its Operational Land Imager (OLI) that identifies thin, high-altitude cirrus clouds that are difficult to see and can skew pixel data. In the image on the left, cirrus formations drift above the landscape. On the right, those cirrus clouds are difficult to discern in the natural-color Landsat 8 image that looks down on Columbia, S.C., and across the border north to Charlotte, N.C.
January 7, 2016 - New Year’s Flooding in the Midwest
At the end of 2015, a series of storms dropped 6–10 inches of rain in a few days over the central part of the United States. Missouri and Illinois were particularly hard hit. Flowing north to south at the top center of the image is the Wabash River, which forms the border between Illinois and Indiana. The Wabash flows into the Ohio River. Water is blue in these images. The December 8, 2015, image shows the rivers at normal water levels. The January 1, 2016, image shows the swollen Wabash and Ohio Rivers, each of them submerging the floodplains.
October 29, 2015 - Death Valley 1,000-year Flood Event
This October, a system of storms caused significant flooding in most of Death Valley National Park, California. Flash floods from the storm destroyed roads and utilities, and damaged several historical structures. This image pair contrasts an October 2014 image (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 lakebed. In the 2015 image, it is full of water.
August 14, 2015 - Suez Canal Expansion, Egypt
A massive expansion project added an additional shipping lane in the Suez Canal, and it only took one year to complete. Egypt celebrated the opening of the new Suez Canal in a ceremony on August 6. The expansion includes 21 miles of new channels and will shorten waiting times. The canal’s extra lane is clearly visible in Landsat imagery. Compare the 2014 and 2015 Landsat 8 images to see the location of the new channel near Ismailia, Egypt.
May 18, 2015 - 35th Anniversary of Mount St. Helens Eruption
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 the Landsat false-color images above, forest appears as bright red interspersed with patches of logging. Snow appears white, and ash is gray. Use the slider to see the widespread effects of the huge blast.
Mount St. Helens Today
A more recent Landsat image shows gradual 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.
April 24, 2015 - The Rio Grande in Drought
The Rio Grande River runs from southern Colorado’s San Juan Mountains to the Gulf of Mexico. In recent years the western United States has experienced a drought that continues to persist. Due to low rainfall and less snowmelt in the mountains, the Rio Grande River is showing the effects of this drought. In the Landsat satellite images above you can see a small portion of the river near Hatch, New Mexico. In the 2008 image, the river is the blue line flanked by green farm fields. The 2015 image shows dry patches in the riverbed where water once flowed. The waterway is now facing a fifth consecutive year of drought.
March 4, 2015 - New land forming in the Atchafalaya Bay
While most of the delta plain along the Louisiana coast is losing ground, new land is forming in the Atchafalaya Bay at the mouths of the Wax Lake Outlet and the Atchafalaya River. In the 1950s, geologists first noticed mud deposits building up in Atchafalaya Bay, but after a severe flood in 1973, new land began to rise above the water line. Since then, the two deltas have grown considerably. The Landsat satellite images above illustrate the growth of the deltas between 1984 and 2014.
See the full story at the NASA Earth Observatory.
January 22, 2015 - Super Stadium
The University of Phoenix Stadium in Glendale, Arizona, will be the location of Super Bowl XLIX. As seen in the USGS High-Resolution Orthoimagery above, the stadium’s roof can open and close. Another feature about the stadium is that the natural grass field can be rolled outside to get sunlight, then rolled inside before a game. The Landsat 8 image, on the left, uses near-infrared light to display vegetation as red. The red pixels just southeast of the stadium show that at the time the image was acquired, the field was outside enjoying the sun.
January 12, 2015 - Sampson Flat Fire, Australia
The Sampson Flat Fire started on January 2, 2015, near Adelaide, Australia. Changing wind conditions caused the fire to spread quickly and move erratically. By January 7, it had burned over 120 square kilometers (46 square miles). In the Landsat 8 image acquired on January 4, the burned areas are dark brown. Active fire appears red with white-blue smoke rising from it.