Author(s): Hantao Wang, Xiaoxiao Zhang

Linked Author(s):

Keywords: Daily precipitation; TMPA; IMERG; Statistical analysis and evaluation; Three Gorges Region basin;

Abstract: We used precipitation data from ground stations (GAUGE) and statistical analysis to evaluate the accuracy of Day-1 Integrated Multi-satellite Retrievals for GPM (IMERG) satellite precipitation product in the Three Gorges Region basin. Accuracy was compared with its predecessor TRMM Multi-satellite Precipitation Analysis (TMPA). Our results show that: (1) TMPA and IMERG were more accurate on a basin scale but their accuracies were also acceptable on the grid scale. (2) The overall performance of IMERG was better than TMPA in the 2014 hydrological year, including the flood season and the dry season. IMERG is more sensitive to light precipitation than TMPA. The probability density function (PDF) of precipitation ( < 5 ) mm estimated by IMERG was often higher than that of GAUGE and it needs to be further optimized. (3) The R of each grid in the basin was generally larger than 0.5, and the RMSE was generally less than 10 mm in the basin. In the canyon alpine area of the lower reaches of the basin, TMPA and IMERG underestimated the measured precipitation GAUGE. In the flat basin area of the upper reaches of the basin, TMPA and IMERG overestimated the measured precipitation GAUGE. (4) R fluctuated over time. RMSE and ME in the flood season was greater than in the dry season.

DOI: https://doi.org/10.3850/38WC092019-0286

Year: 2019