A global dataset of the shape of drainage systems

Abstract. Drainage basins delineate the Earth’s land surface into individual water collection units. Basin shape and river sinuosity determine water and sediment dynamics, affecting landscape evolution and connectivity between ecosystems and freshwater species. However, a high-resolution global dataset for the boundaries and geometry of basins is still missing. Using a 90-meter resolution digital elevation model, we measured the areas, lengths, widths, aspect ratios, slopes, and elevations for basins greater than 50 km2 globally. Additionally, we calculated the lengths and sinuosities of the longest river channels within these 0.67 million basins. We built a new global dataset, Basin90m, to present the basins and rivers, as well as their morphological metrics. To highlight the use cases of Basin90m, we explored differences between the nine stream orders, spatial distribution of drainage systems, and correlations between morphological metrics, such as Hack’s law. By comparing with HydroSHEDS, Goole Earth images, and a few other datasets, we have demonstrated the high accuracy of Basin90m. Basin90m, available in Shapefile format, can be used in various GIS platforms, including QGIS, ArcGIS, and GeoPandas. Basin90m has substantial application prospects in geomorphology, hydrology, and ecology.