Abstract:
The Global Precipitation Measurement (GPM) mission′s release of IMERG V07 in 2024 provides a new data source for precipitation monitoring.However, its performance across complex terrains and diverse climatic regimes remains to be rigorously evaluated.This study comprehensively evaluates the applicability of IMERG V07 across China and its improvements over the preceding V06 version.We develop an innovative multi-scale evaluation framework that integrates observations from 699 meteorological stations with the high-precision 0.25℃N05.1 gridded precipitation dataset, enabling systematic comparison between IMERG Late V07 and V06 at both station scale (2004~2020) and grid scale (2018~2020).Results reveal that V07 demonstrates significant improvements over V06 at the station scale, with an average increase of 0.05 in correlation coefficient and reductions of 6.96%, 4.18%, and 18.55% in
RMSE,
MAE, and
PBIAS, respectively.Notably, V07 enhances detection capabilities for light precipitation (≤10 mm/d) and heavy precipitation (≥50 mm/d) by 4.65% and 11.58%, respectively.At the grid scale, V07 more accurately captures China′s precipitation spatial patterns, particularly improving solid and trace precipitation identification in arid western regions (correlation coefficient increases of 0.1~0.2) and heavy precipitation event detection in eastern coastal areas (RMSE reductions exceeding 30%).The findings demonstrate that IMERG V07 exhibits superior applicability across China′s complex terrain and diverse climate zones, providing more reliable data support for hydrological modeling, drought monitoring, and flood forecasting applications.