Evaluating reanalysis and satellite-based precipitation at regional scale: A case study in southern Mexico

Accurate precipitation data is essential for any hydrometeorological study, particularly calibration and simulation of hydrological models. In this paper, we evaluate the two different reanalysis products (the ERA5 GLDAS), satellite-based (TRMM 3B42 CHIRPS) over La Sierra river basins in Southern Mexico, on regional daily time scales, from 2008 to 2010. We compare collocated gridded against in-situ measurements each gauge station, as well mean areal (MAP) catchments study area products. The Pearson correlation coefficient, root square error, multiplicative bias metrics suggest that CHIRPS are highest quality area. performs better grid point comparison, estimating events 10-50 mm, above 100 all values without threshold. does 0-10 50-100 mm. These datasets also have performance representing spatial rainfall variability according annual MAP analysis, showing statistical close other.