A Quantitative Quest for the Most Representative Precipitation Data Sets in Diverse Environments

The study of water distribution and movement in the Earth's atmosphere and on its surface plays a pivotal role in understanding the intricate dynamics of water resources crucial for sustaining ecosystems, agriculture, and human societies worldwide. Therefore, precipitation data becomes a linchpin, shaping the foundation for informed decision-making in water resource management and environmental planning. This study undertakes a comprehensive comparison of 20 precipitation data sets (CMAP, CMORPH, CPC-Global, CRU TS v4.07, EM-Earth, ERA5, ERA5-Land, FLDAS, GPCC v2020, GPCP v3.2, GPM IMERGM v07, GSMaP v8, JRA55, MERRA-2, MSWEP v2.8, NCEP/DOE R2, NCEP/NCAR R1, PERSIANN-CDR, PREC/L, TerraClimate), aiming to identify the most suitable data set under diverse scenarios. Our research addresses the needs of different spatial domains, including individual countries, IPCC AR reference regions, and major river basins, with a variety of geographical features such as land cover types, elevation zones, biomes, and Köppen-Geiger climate classifications. We rigorously assess each data set's performance through a quantitative analysis, seeking to unravel reliability patterns specific to distinct regions and climatic conditions. By tailoring our recommendations to the unique characteristics of each setting, we contribute to the refinement of hydrological modeling and decision-making processes. Such efforts not only contribute to the advancement of hydrological sciences but also to the broader nexus fields, where robust precipitation data serves as a cornerstone for modeling and projecting climate change impacts.