Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- South America

• 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; imageryBaseMapsEarthCover; South America; Greenland
• Online Access: https://search.dataone.org/view/b4201912-8506-4a84-8116-42b7760183e3

This contains the South American portion of the Hydrologic Derivatives for Modeling and Analysis (HDMA) database. The HDMA database provides comprehensive and consistent global coverage of raster and vector topographically derived layers, including raster layers of digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and vector layers of streams and catchment boundaries. 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.