Evaluation of CMPAS precipitation products over Sichuan, China

Abstract

High-quality and high-resolution precipitation data are the basis for mesoscale numerical weather forecasting, model verification, and hydrological monitoring, which play an important role in meteorological and hydrological disaster prevention and mitigation. In this study, high-density rain gauge data are used to evaluate the fusion accuracy of the China Meteorological Administration Multisource Precipitation Analysis System (CMPAS), and four CMPAS products with different spatial and temporal resolution and different data sources are compared, to derive the applicability of CMPAS. Results show that all the CMPAS products show high accuracy in the Sichuan Basin, followed by Panxi Area and the western Sichuan Plateau. The errors of the four products all rise with the increase in precipitation. CMPAS overestimates precipitation in summer and autumn and underestimates it in spring and winter. Overall, the applicability of these fused data in the Sichuan Basin is quite good. Due to the lack of observations and the influence of the terrain and meteorological conditions, the evaluation of CMPAS in the plateau area needs further analysis.摘要高质量和高分辨率的降水产品在天气预报, 数值模式模拟和气象防灾减灾方面起着重要的作用. 本文利用四川地区高密度的地面降水传感器观测数据, 比较CMPAS四种不同时空尺度的降水实况分析产品, 评估CMPAS的融合准确性与在四川地区的适用性. 研究表明:四种CMPAS降水产品都在四川盆地内精度较高, 攀西地区和川西高原次之. 随着降水量的增加, 产品的误差也随之增加. CMPAS在夏秋两季对降水量高估, 在春冬两季对降水量低估. 总而言之, CMPAS在四川盆地内与观测数据的融合准确性较高. 由于高原地区气象观测站点数量不足且观测数据受复杂地形和气候条件影响较大, CMPAS在高原地区的适用性检验仍需进一步研究.