Global‐scale regionalization of hydrologic model parameters

Abstract Current state‐of‐the‐art models typically applied at continental to global scales (hereafter called macroscale) tend to use a priori parameters, resulting in suboptimal streamflow ( Q ) simulation. For the first time, a scheme for regionalization of model parameters at the global scale was developed. We used data from a diverse set of 1787 small‐to‐medium sized catchments ( km 2 ) and the simple conceptual HBV model to set up and test the scheme. Each catchment was calibrated against observed daily Q , after which 674 catchments with high calibration and validation scores, and thus presumably good‐quality observed Q and forcing data, were selected to serve as donor catchments. The calibrated parameter…