However, the amount of cloud cover affected the accuracy of ASTER which wasn’t the case for SRTM DEM. Based on two images at different angles, it used stereo pairs and photogrammetry to measure elevation. Despite its high-resolution and greater coverage (80% of the Earth), dissatisfied users expressed issues with its artifacts often in cloudy areas.ĪSTER GDEM used stereoscopic pairs and digital image correlation methods. As part of this project emerged the ASTER Global Digital Elevation Model (GDEM).ĪSTER GDEM boasted a global resolution of 90 meters with a resolution of 30 meters in the United States.
NASA and Japan’s joint operation was the birth of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER).
#DSM DIGITAL TERRAIN MODEL DOWNLOAD#
But here’s a USGS Earth Explorer download guide to help you get started. Under the data sets tab, select Digital Elevation > SRTM > SRTM 1-ArcSecond Global . To download, select your area of interest. SRTM DEM data is being housed on the USGS Earth Explorer. Also, it covers most of the world with an absolute vertical height accuracy of less than 16m. This 1-arc second global digital elevation model has a spatial resolution of about 30 meters. In late 2014, the United States government released the highest resolution SRTM DEM to the public. C-Band penetrated canopy cover to the ground better but SRTM still struggled in sloping regions with foreshortening, layover and shadow. Using two radar antennas and a single pass, it collected sufficient data to generate a digital elevation model using a technique known as interferometric synthetic aperture radar (inSAR). Back in February 2000, the Space Shuttle Endeavour launched with the SRTM payload. NASA only needed 11 days to capture Shuttle Radar Topography Mission (SRTM) 30-meter digital elevation model. Space Shuttle Radar Topography Mission (SRTM)
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