NCEP和GRAPES作为WRF模式背景场的宁夏暴雨模拟效果对比分析

Comparative Analysis of Rainstorm Simulation Effects of NCEP and GRAPES as the Background Field of WRF Model in Ningxia

摘要: 本文使用宁夏本地化的高分辨率中尺度WRF模式，分别选取美国的NCEP和中国的GRAPES全球数值预报模式作为初始场和边界条件，对2020年出现的暴雨过程进行数值模拟，并结合实况进行对比检验，分析暴雨发生时两种不同背景场下的WRF模拟效果。同时对2020年8月23日降水过程模拟结果进行对比。结果表明：无论从降水逐月检验还是要素场逐月检验，均为NCEP优于GRAPES。对于2020年8月23日过程，NCEP做初始场输出结果无论从高空高度场还是低空风场及相对湿度来看都与实况更接近，位置也与降水中心更符合。

Abstract: In this paper, the high-resolution mesoscale WRF model localized in Ningxia is used to simulate the rainstorm process in 2020 by selecting the NCEP in the United States and the GRAPES global numerical forecast model in China as the initial field and boundary conditions, and comparing the WRF simulation effect under two different background fields during the rainstorm. At the same time, the simulation results of the precipitation process on August 23, 2020 were compared. The results show that NCEP is better than GRAPES in both precipitation and factor field tests. For the process on August 23, 2020, the initial field output results of NCEP are closer to the actual situation in terms of high-altitude field, low-altitude wind field and relative humidity, and the location is more consistent with the precipitation center.