HDMA: Global Topographic Derivatives for Hydrology

Hydrologic Derivatives for Modeling and Analysis (HDMA) provides a globally consistent set of raster and vector layers derived from elevation data. The database includes five raster layers, such as digital elevation models and flow direction, and three vector layers, including streams and catchment boundaries. It was created by Kristine L. Verdin of the United States Geological Survey and combines data from HydroSHEDS, GMTED2010, and SRTM sources.

Use Cases

• Modeling surface water flow based on global flow direction and accumulation rasters.
• Delineating watersheds and catchments based on the provided vector boundaries and Pfafstetter codes.
• Analyzing terrain characteristics for environmental studies using slope and compound topographic index layers.
• Integrating topographic data for hydrological applications using the hybrid global DEM coverage.

Strengths

• Global spatial coverage from -180 to 180 degrees longitude and -90 to 90 degrees latitude.
• Combines data from three authoritative sources: HydroSHEDS, GMTED2010, and SRTM.
• Includes both raster (e.g., DEM, slope) and vector (e.g., streams, catchments) data products.
• Streams and catchments are attributed with Pfafstetter codes for topological analysis.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Last update date is unknown; freshness unverified.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

United States Geological Survey

Collection Method

Derived from a hybrid of HydroSHEDS, Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010), and Shuttle Radar Topography Mission (SRTM) data.

Geography

Global