ates where the fire is burning. Burned areas are dark shades, and smoke from the fire forms a hazy trail toward the south. The Susitna River, to the west of the burned area, acts as a natural firebreak.
Landsat imagery assists with response planning and identification of areas at further burn risk. Future Landsat imagery will be useful for mapping and measuring burned areas and monitoring vegetation recovery.
Heavy rains fell over Texas, Oklahoma, Arkansas, and Louisiana in late May 2015. Many lakes and rivers filled and overflowed their banks, causing widespread flooding in both urban and rural areas. These rains provided much-needed moisture for this area of the southern Plains, and may help to suspend a multiyear drought in the region. However, the rapid rate of the rainfall has been excessive for many areas.
These images show the Trinity River southeast of Dallas, Texas. In the May image, the river can hardly be seen because of the vegetation along its banks. The June image shows Trinity River and flooded regions in bright blue and dark tones.
As the water moves downstream, continued flooding is affecting many homes, businesses, and cropland within Texas and its neighboring states. Future Landsat images will help with the monitoring and evaluation of impacts, as the waters crest and begin to recede.
2015 Earthquake and Landslides, Nepal May 27, 2015
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 Buri Gandaki 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.
35th Anniversary of Mount St. Helens Eruption May 20, 2015
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. Wi