Comparisons of WRF and GLDAS precipitation products in the Heihe river basin

As precipitation data being an essential forcing data to hydrological and land surface models, its quality has great impacts on simulation. For the absence of fine resolution and good quality precipitation data in the Heihe river basin (HRB), precipitation data from WRF and GLDAS are extensively used for model simulation in HRB. So, it is necessary to evaluate the two precipitation data sources in HRB. A comprehensive comparative evaluation approach, consisting of statistical indicators including both temporal, spatial aspects and comparisons against in situ observations from four established meteorological sites in the upper HRB, is proposed in this study. Hourly WRF precipitation in 5 km resolution and 3-hr GLDAS precipitation was interpolated to the same resolution as WRF in a long period of 2004-2009 are evaluated. The results show that each of them has advantages and disadvantages, but comparatively, WRF is advanced in both temporal and spatial resolution.