NASADEM: Global Digital Elevation Model at 1 Arc Second Resolution

NASADEM_HGT is a global digital elevation model providing surface height data at 1 arc second spacing, covering land between 60° N and 56° S latitude. The dataset was produced by NASA's LP DAAC, derived from Shuttle Radar Topography Mission (SRTM) telemetry and enhanced with ASTER GDEM, ICESat GLAS, and other data sources. It was last updated on March 12, 2026.

Use Cases

• Modeling hydrological flow and watersheds based on global terrain elevation.
• Analyzing landform and topographic features for geological studies.
• Generating 3D terrain visualizations and maps using the elevation data layers.
• Improving geolocation accuracy for other remote sensing products using the ground control points mentioned.

Strengths

• Covers approximately 80% of Earth's total landmass.
• Derived from multiple authoritative sources including SRTM, ASTER GDEM, and ICESat GLAS.
• Includes ancillary data layers such as a water mask and a scene count (NUM) layer.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Data coverage is limited to land between 60° N and 56° S latitude, excluding polar regions.

Provenance

Source

National Aeronautics and Space Administration (NASA) via the Land Processes Distributed Active Archive Center (LP DAAC).

Collection Method

Derived from original SRTM telemetry and enhanced with ASTER GDEM, ICESat GLAS lidar ground control, and other DEMs for void filling and geoid conversion.

Time Range

Primary SRTM data was collected during the STS-99 mission launched on February 11, 2000.

Freshness

Last updated 2026-03-12 23:27:24.860950; freshness should be verified.

Geography

Global coverage of land between 60° N and 56° S latitude.