Rainfall spatial variability in the application of Catchment Morphing for ungauged catchments

Abstract

Catchment Morphing (CM) is a newly proposed approach to apply fully distributed models for ungauged catchments and has been trialled in several catchments in the UK. As one of the most important input datasets for hydrological models, rainfall spatial variability is influential on the stream variabilities and simulation performance. A homogenous rainfall was utilized in the previous experiments with Catchment Morphing. This study applied a spatially distributed rainfall from CEH-GEAR rainfall dataset in the morphed catchment for ungauged catchments as the follow-on study. Three catchments in the UK were used for rainfall spatial analysis and CEH-GEAR rainfall data were adopted for additional spatial analysis. The results demonstrate the influence of rainfall spatial information to the model performance with CM and illustrate the ability of morphed catchment to deal with spatially varied information. More spatially distributed information is expected to be introduced for a wider application of CM. HIGHLIGHTS Rainfall spatial variability is important for streamflow predictions.; Catchment Morphing is a useful approach for ungauged catchments.; Spatially variable rainfall inputs can benefit streamflow predictions using Catchment Morphing.;

Keywords

• catchment morphing
• rainfall spatial variability
• streamflow prediction
• ungauged catchments