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Topographic derivative datasets for the Geospatial Fabric for National Hydrologic Modeling, Alaska Domain

Published by U.S. Geological Survey | Department of the Interior | Metadata Last Checked: July 15, 2025 | Last Modified: 20241204
The Geospatial Fabric for National Hydrologic Modeling (Viger and Bock, 2014; Bock and others, 2020) is a dataset of hydrographic features and spatial data designed for use within the National Hydrologic Model that covers the conterminous United States (CONUS), Hawaii, and most major river basins that flow in from Canada. This U.S. Geological Survey (USGS) data release consists of the geospatial fabric features and other related spatial datasets created to expand the National Hydrologic Model to Alaska. This child item consists of topographic data themes that cover the Geospatial Fabric for National Hydrologic Modeling, Alaska Domain. The 30-meter (m) raster datasets included under Topographic Derivatives are: digital elevation (dem.tif), topographic wetness index (TWI, twiX100.tif), slope (rise over run, slope.tif), aspect (asp.tif), flow accumulation (fac.tif), and flow direction (fdr.tif). All file formats are in GeoTIFF (Geographic Tagged Imaged Format), and are sourced from NHDPlus Version 2.0 raster layers (Environmental Protection Agency, 2019)

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