Global Dominant River Tracing (DRT) based Hydrography Datasets for Macroscale Hydrological Modeling

The DRT algorithms are based on the D8 single direction flow method. In contrast with previous upscaling methods, the DRT algorithms utilize information on global and local drainage patterns from baseline fine scale hydrography inputs to determine upscaled flow directions and other critical variables including upscaled basin area, basin shape and river lengths.

The DRT algorithm preserves the original baseline hierarchical drainage structure by tracing each entire flow path from headwater to river mouth at fine scale while prioritizing successively higher order basins and rivers for tracing. We applied the algorithm to produce a series of global hydrography data sets from 1/16° to 2°spatial scales in two geographic projections (WGS84 and Lambert azimuthal equal area). The DRT results were evaluated against other alternative upscaling methods and hydrography datasets for continental USA and global domains.