关键词: 川渝地区, 降水融合产品, CMPAS, GSMaP, IMERG, 误差分析

Abstract: Three sets of precipitation fusion products CMPAS, GSMaP and IMERG in the flood season of 2021, and the hourly precipitation data of 190 national meteorological stations in Sichuan and Chongqing region after quality control were used to test the error analysis of the three sets of products in combination with different terrain intervals and different hourly rainfall intensity in Sichuan and Chongqing region, so as to provide data support for flood season hydrometeorological disaster prevention and reduction. Some results in this study showed that: (1) in terms of the spatial distribution of total rainfall in 2021 flood season, CMPAS products were the closest to the site measured precipitation, followed by GSMaP and IMERG products. (2) According to different topographic areas and different time periods, CMPAS products had the best correlation, hit rate and key success rate, followed by IMERG. The deviation, root mean square error and false positive rate of CMPAS products were the smallest, the false positive rate of GSMaP products was the largest, and the deviation and root mean square error of IMERG products were the largest. The hit rate and critical success rate of all fusion products were the best in August and September, and the correlation, hit rate and critical success rate were the best in 20：00−next 2：00 and 2：00−8：00, while the error and false positive rate were the least. (3) CMPAS was obviously better than IMERG and GSMaP for different hourly rainfall intensity. The correlation, hit rate and critical success rate of CMPAS products in May and September were the best. As the hourly rain intensity increased, the root mean square error of each fusion product increased gradually. The above results indicate that the accuracy of CMPAS products in flood season was obviously better than that of IMERG and GSMaP products in Sichuan and Chongqing, which could provide effective precipitation data supplement for areas lacking ground measured data.

Key words: Sichuan and Chongqing region, Precipitation fusion product, CMPAS, GSMaP, IMERG, Error analysis