NASA Airborne Snow Observatory measurements of snow water equivalent (top image) and snow albedo, or reflectivity (bottom image) for the Tuolumne River Basin in California's Sierra Nevada on April 21, 2013.

NASA Airborne Snow Observatory measurements of snow water equivalent (top image) and snow albedo, or reflectivity (bottom image) for the Tuolumne River Basin in California's Sierra Nevada on April 21, 2013. The snow water equivalent measured the total water contained as snow in the basin on that date at 375 million cubic meters, or enough to fill the Rose Bowl about 1,180 times. The albedo map expresses the percentage of sunlight reflected back to space by the snow. The lower the albedo, the faster the snowmelt rate and runoff.

For more information about the Airborne Snow Observatory, visit: http://aso.jpl.nasa.gov/. For more on NASA's Airborne Science program, visit: http://airbornescience.nasa.gov.

The California Institute of Technology in Pasadena manages JPL for NASA.

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