Acronyms: ALOS - Advanced Land Observing Satellite AMSR-E - Advanced Microwave Scanning Radiometer - EOS DEM - Digital Elevation Model EOS - Earth Observing System ERS - European Remote Sensing ESA - European Space Agency ESDR - Earth System Data Record GTOPO - Global Topography JAXA - Japan Aerospace Exploration Agency JERS - Japanese Earth Resources Satellite JPL - Jet Propulsion Laboratory NASA - National Aeronautics and Space Administration NSCAT - NASA Scatterometer PALSAR - Phased Array type L-band Synthetic Aperture Radar QuikSCAT - Quick Scatterometer SAR - Synthetic Aperture Radar SRTM - Shuttle Radar Topography Mission SSM/I - Special Sensor Microwave/Imager USGS - United States Geological Survey