EarthWorks Geospatial Catalog

Asia: Flow Accumulation, 30s resolution, 2007

HydroSHEDS (Hydrological data and maps based on SHuttle Elevation Derivatives at multiple Scales)flow accumulation maps define amount of upstream area (in number of cells) draining into each cell for Asia. Drainage direction layers are used to define which cells flow into the target cell. Cells with a high flow accumulation are areas of concentrated flow and may be used to identify stream channels. The number of accumulated cells is essentially a measure of upstream catchment area. Because cell size of data set depends on latitude, the cell accumulation value cannot directly be translated into drainage areas in square kilometers. This data is derived from elevation data of the Shuttle Radar Topography Mission (SRTM) at 30 arc-second resolution approx. 1km at the equator.The goal of developing HydroSHEDS was to generate key data layers to support regional and global watershed analyses, hydrological modeling, and freshwater conservation planning at a quality, resolution and extent that had previously been unachievable.
U.S. Geological Survey
Hydrology, Hydrography, Watersheds, Digital elevation models, Elevation, Inland Waters, and Imagery and Base Maps
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Use and reproduction
Users may apply HydroSHEDS for non-commercial purposes. Any modification of the original data by users must be noted. The authors of HydroSHEDS may request reprints of publications and copies of derived materials. The user shall not reproduce, convert, (re)publish, (re)distribute, (re)broadcast, (re)transmit, sell, rent, lease, sublicense, lend, assign, time-share, or transfer, in whole or in part, or provide unlicensed third parties access to the data and related materials without explicit written permission from the authors. We kindly ask users to cite HydroSHEDS in any published material produced using this data. If possible, please provide online links to for general information, and/or for data download and technical information.
HydroSHEDS has been generated through the extensive use and incorporation of data products provided by various other authors. The data and related materials may thus contain proprietary and confidential property of these authors and/or their licensor(s). HydroSHEDS data and related materials are protected by United States copyright or sui generis laws and applicable international copyright treaties and/or conventions.
Attribution Non-Commercial 3.0 Unported
Attribute Value
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