Hydrologic Derivatives for Modeling and Applications (HDMA) database

• Main Author: Kristine L. Verdin
• Format: Dataset
• Language: unknown
• Published: USGS Science Data Catalog 2017
• Subjects: dem stream hydrologic derivatives pfafstetter; Pfafstetter; streams; digital elevation models; elevation; inlandWaters; North America; South America; Africa; Asia; Asia Minor and Middle East; Europe; Australia; Australia and New Zealand; Pacific Islands; Greenland; New Zealand; Pacific
• Online Access: https://search.dataone.org/view/22af343c-35cc-4a38-94e8-a1a1786e065e

The Hydrologic Derivatives for Modeling and Analysis (HDMA) database provides comprehensive and consistent global coverage of raster and vector topographically derived layers. The HDMA includes five raster layers: digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and three vector layers: streams, catchment boundaries, and processing units. The coverage of the data is global (-180º, 180º, -90º, 90º) with the underlying DEM being a hybrid of three datasets: HydroSHEDS (Hydrological data and maps based on SHuttle Elevation Derivatives at multiple Scales), Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010) and the Shuttle Radar Topography Mission (SRTM). For most of the globe south of 60º North, the raster resolution of the data is 3-arc-seconds, corresponding to the resolution of the SRTM. For the areas North of 60º, the resolution is 7.5-arc-seconds (the smallest resolution of the GMTED2010 dataset) except for Greenland, where the resolution is 30-arc-seconds. The streams and catchments are attributed with Pfafstetter codes, based on a hierarchical numbering system, that carry important topological information.