Item

Abstract

The current global dataset of drainage system shapes has a relatively low spatial resolution. We obtained a new dataset (Basin90m) by calculating the drainage basins larger than 50 km2 globally using a 90-meter resolution Digital Elevation Model (DEM). The total number of drainage basins is 667629. For each drainage basin, we extracted the spatial distribution of the longest river channel and the sinuosity of the river. We computed fundamental geometric parameters for the drainage basins, such as area, length, width, aspect ratio, slope, and elevation. Basin90m consists of vector files (ESRI Shapefile format) containing global drainage basins and river channels. The file sizes for the basin and river data are 7.8 and 2.5 GB, respectively. All calculations were automated using a MATLAB script. For a more detailed description of Basin90m, please refer to our submitted data description article titled "A global dataset of the shape of drainage systems". The Basin90m dataset includes data in four sections. The first section comprises drainage basins globally with an area larger than 50 km². The data format is ESRI Shapefile. Eight morphometric indi-ces of the drainage system are stored in the attribute table of the basin shapefile. The "Basins" folder contains six subfolders, each representing a continent. Each continent's subfolder contains all the basins in that continent, categorized by different stream orders. For instance, the "South America" subfolder contains nine shapefile files corresponding to stream orders 1-9. The names of the shapefile files include their continent and stream order information. For example, "South_America_Basin_8.shp" represents all basins in South America with a stream order of 8. The second part of the Basin90m data consists of global main river channels. The longest river channel of each basin is stored in a folder named "Rivers". The internal structure of this folder is the same as the "Basins" folder. For instance, "South_America_River_8.shp" represents the main river channels in South America with a stream order of 8. The third part of Basin90m data is an Excel file named "Basin90m". This file contains eight morphometric parameters for all the basins. It includes both a globally merged sheet and sheets distinguishing different stream orders. The fourth part of Ba-sin90m data is a folder named "Matlab_code", which contains Matlab code for the automated ex-traction of drainage systems and their morphometric parameters.