Slope from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Greenland

This dataset contains the slope for Greenland from 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.

本数据集包含取自水文建模与分析衍生数据库（Hydrologic Derivatives for Modeling and Analysis，HDMA）的格陵兰岛坡度数据。该数据库提供覆盖全球的一致地形衍生栅格与矢量图层产品，涵盖数字高程模型（Digital Elevation Model，DEM）数据、流向、汇流累积量、坡度及复合地形指数（Compound Topographic Index，CTI）等栅格图层，以及水系与流域边界矢量图层。本数据集的全球覆盖范围为(-180°，180°，-90°，90°)，其基础数字高程模型融合了三类数据集：多尺度航天飞机高程衍生水文数据与地图（HydroSHEDS）、全球多分辨率地形高程数据2010（Global Multi-resolution Terrain Elevation Data 2010，GMTED2010）以及航天飞机雷达地形测绘任务（Shuttle Radar Topography Mission，SRTM）的数据。全球北纬60°以南的大部分区域，该数据集的栅格分辨率为3角秒，与SRTM的分辨率一致。北纬60°以北的区域，栅格分辨率为7.5角秒（为GMTED2010数据集的最小分辨率），但格陵兰岛除外，该区域的分辨率为30角秒。水系与流域边界图层附带基于分层编号系统的普法夫施泰特编码（Pfafstetter codes），该编码承载了重要的拓扑信息。