Multiscale Ground Validation of Satellite and Reanalysis Precipitation Products over Diverse Climatic and Topographic Conditions

The validity of two reanalysis (ERA5 and MEERA2) seven satellite-based (CHIRPS, IMERG, PERSIANN-CCS, PERSIANN-CDR, PERSIANN-PDIR, PERSIANN, TRMM) precipitation products was assessed in relation to the observations situ weather stations installed different topographical climatic regions Pakistan. From 2010 2018, all were evaluated on daily, monthly, seasonal, annual bases at a point-to-pixel scale over entire spatial domain. accuracy using commonly used evaluation categorical indices, including Root Mean Square Error (RMSE), Correlation Coefficient (CC), Bias, Relative Bias (rBias), Critical Success Index (CSI), Ratio (SR) Probability Detection (POD), False Alarm (FAR). results show that: (1) Over country, spatio-temporal distribution observed could be represented by IMERG TRMM products. (2) All (reanalysis SPPs) demonstrated good agreement with reference data monthly compared daily (CC > 0.7 scale). (3) other outperformed terms their capacity detect events throughout year, regardless season (i.e., winter, spring, summer, autumn). Furthermore, both (IMERG consistently depicted incidence across Pakistan’s various topography regimes. (4) Generally, CHIRPS ERA5 showed moderate performances plan areas. PDIR, MEERA2 uncertain occurrence higher intensities altitudes. Considering finding this assessment, we recommend use estimates product for hydro studies