Abstract:
Using the precipitation data of Shaanxi Province from 2019 to 2023 and the real-time products of the CMA Multi-source Precipitation Analysis System (CMPAS-V2.1) in the same period, the temporal and spatial characteristics of regional rainstorms in Shaanxi Province over the past five years were analyzed briefly, and the accuracy of the multi-source precipitation products were evaluated with statistical test method. The results show that: (1) The main peak of regional rainstorm occurred from mid-July to early August, and the secondary peak occurred in late August and mid-September to early October. The large precipitation value areas were located in the eastern and southern parts of northern Shaanxi and the central and western parts of southern Shaanxi. (2) Multi-source precipitation products could basically reflect the observed precipitation, but there were deviations in the heavy precipitation region. Areas with high root mean square error were closely related to heavy precipitation zones. The absolute error of multi-source products increased with the increase of precipitation intensity. The light rain value of multi-source product was larger, and the values of other precipitation levels were smaller. (3) The errors of low-vortex type heavy rain and rainstorm, low-trough-typhoon type moderate rain and above were obviously greater than those of other types, which should be corrected in future application. For heavy rain and rainstorm intensities, the two-source products of low-trough-typhoon heavy rain and rainstorm were better, while the three-source products of other circulation types were better. (4) Comparing different regional types, errors were relatively larger for the northern-Shaanxi type and smaller for the province-wide type. For province-wide rainstorms, the three-source product outperformed the two-source product, whereas for other types of rainstorms, the two-source product was more accurate.