Topographic Wetness Indexes for the Upper and Lower Colorado River Basins

This U.S. Geological Survey (USGS) data release describes two 30-meter (m) raster datasets of topographic wetness indexes (TWI) for the Upper and Lower Colorado River basins. The data reside in GeoTIFF (Geographic Tagged Imaged File Format) multiplied by 10 and saved as an integer file to reduce space (colorado14_twX100i.tif and colorado15_twiX100.tif). The TWI units are dimensionless. The dataset resides in the Albers96 NAD83 projection. The source data used were 30-meter digital elevation (DEM) models from the NHDplus Version 2 data suite (U.S. Environmental Protection Agency, 2012).

本美国地质调查局（U.S. Geological Survey, USGS）发布的数据集包含两套针对科罗拉多河上、下游流域的30米分辨率地形湿度指数（Topographic Wetness Index, TWI）栅格数据集。该数据集采用地理标记图像文件格式（Geographic Tagged Image File Format, GeoTIFF）存储，为压缩存储空间，数据已乘以10并以整数格式保存，对应文件为colorado14_twX100i.tif与colorado15_twiX100.tif。地形湿度指数单位为无量纲。本数据集采用Albers96 NAD83投影坐标系。本次数据集的源数据为美国环境保护署（U.S. Environmental Protection Agency, 2012）发布的NHDplus第二版数据集中的30米数字高程模型（Digital Elevation Model, DEM）。