By the time the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite passed over Des Moines, Iowa, on June 29, 2008, and captured this image, the floods that had struck the city in mid-June when an aging levee failed were no longer apparent in the city itself. However, downstream (southeast) of the city, the flooding remained dramatic.
This pair of false-color images uses a combination of visible and infrared light observed by ASTER to enhance the appearance of standing water (dark blue). Vegetation appears bright red, urban landscapes and roads appear silver-gray, and clouds are white. The clouds cast black shadows to their northwest. The brightness of the floodwater in the June 29 image may be because the water is muddy, but it could also be because of sunglint, or glare.
The Des Moines River flows into the scene from the north, cuts through the city, and heads southeast. Huge pools of flood water spread across the land southeast of the city. The flooded area appears to be a mosaic of agricultural land (rectangular clearings are visible in the lower right corner of the comparison image from June 30, 2005) and open space. Additional flooding is visible upstream of the city in the large version of the image.
The mid-June floods devastated many Midwest cities and inundated thousands of acres of cropland. Additional images related to these floods are available in the Floods in the U.S. Midwest event in the Natural Hazards section of the Earth Observatory Website.