Sacramento-San Joaquin River Delta, CA
The Sacramento-San Joaquin River Delta, CA (or California Delta) has an area of about 3000 km2, and provides a large fraction of all the water used in California. The Delta drains about 50&percnt of the water coming from the Sierra Nevada Mountains, and channels it through San Francisco's Golden Gate to the Pacific Ocean. Thousands of miles of levees now carefully control the Delta's flow, to maximize water use. The image combines a false color infrared composite (with vegetation depicted in red) with a colorized thermal infrared band to show the water temperature for the larger water bodies. Warmer temperatures are red and yellow, cooler water temperatures are blue and green. The image was acquired July 3, 2012, covers an area of 46.5 by 57.5 km, and is located at 38.1 degrees north, 121.3 degrees west.
With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of about 50 to 300 feet (15 to 90 meters), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on Terra. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and data products.
The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change. Example applications are monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.
The U.S. science team is located at NASA's Jet Propulsion Laboratory in Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate, Washington.
More information about ASTER is available at http://asterweb.jpl.nasa.gov/.