NASA Shuttle Radar Topography Mission (SRTM3) Global 3 arc-second number - National Geospatial Data Asset (NGDA)

The first release of Shuttle Radar Topography Mission (SRTM) data was provided in 1-degree digital elevation model (DEM) tiles from the USGS 2003. The data was released continent by continent, as and when the data was processed by NASA and the USGS. For the United States, data was made available at 1-arc second resolution (approximately 30m at the equator), but for the rest of the world the 1-arc second product is degraded to 3-arc seconds (approximately 90m at the equator). SRTM elevation data has now been released for the entire terrestrial surface, and a Finished product has now been released.航天飞机雷达地形测绘任务（Shuttle Radar Topography Mission，SRTM）数据的首次发布于2003年由美国地质调查局（United States Geological Survey，USGS）以1度见方的数字高程模型（Digital Elevation Model，DEM）瓦片形式提供。该数据由美国国家航空航天局（National Aeronautics and Space Administration，NASA）与美国地质调查局（USGS）完成数据处理后，按大洲依次发布。其中，美国本土的数据以1角秒（arc second）分辨率提供（赤道处地面分辨率约为30米）；而全球其余区域的1角秒产品则降级为3角秒分辨率（赤道处地面分辨率约为90米）。目前，SRTM高程数据已覆盖全球全部陆地表面，其最终成品已正式发布。