Applicability evaluation of ERA5 precipitation reanalysis data in the Yangtze River Basin
In order to improve the reanalysis capability of meteorological data in the Yangtze River Basin,this article analyzes the multi time scale changes of ERA5 precipitation reanalysis data products based on daily precipitation observation data from 724 automatic weather stations in the Yangtze River Basin from 1981 to 2020,and evaluates the applicability of ERA5 precipitation reanalysis data products in the Yangtze River Basin using quantitative and categorical statistical indicators.The results indicate that the overall quality of ERA5 precipitation reanalysis data products is good,which can well reflect the annual,monthly,and seasonal trends of precipitation in the Yangtze River Basin,but all show overestimation.The accuracy of products in spring and summer is not as good as in autumn and winter seasons.The product accuracy gradually increases from west to east,and the error also shows a gradual increase from west to east.The product has a strong ability to characterize whether there are precipitation events in the entire basin,but it will decreases with the increase of precipitation level.The false positive rate and fair skill score are the opposite,but overestimation still exists.Therefore,it is necessary to select suitable reanalysis products based on regional and application characteristics.
ERA5 dataprecipitationYangtze River Basintime variationaccuracy evaluation