RegCM3对中国淮河流域降水模拟能力的检验及分析

检验了区域气候模式RegCM3(Regional Climate Model version3)对中国淮河流域(30°55′—36°36′N,111°55′—121°25′E)1982—2001年夏季降水及大尺度环流场的模拟能力,并选取降水明显偏多的2003年夏季为个例,评估了RegCM3模式对该年淮河流域夏季降水的集合模拟能力。模拟的20a降水的空间分布与实测资料对比表明,RegCM3成功地模拟出了淮河流域夏季降水的空间分布和年际变化;通过分析对比RegCM3模拟出的低层850hPa流场结构和水汽输送状况与实测情况,可知RegCM3能模拟出低层流场结构的大致分布和水汽输送特点,但模拟所得风速和湿度均比实况偏大。对2003年淮河流域夏季降水的集合模拟结果表明,RegCM3对中小尺度极端强降水的降水量和降水中心的模拟能力尚有待进一步提高。

Evaluation and analysis of RegCM3 simulated summer rainfall over the Huaihe River basin of China

This study evaluates the ability of the Abdus Salam International Center for Theoretical Physics(ICTP) version 3 Regional Climate Model(RegCM3) to simulate the summer rainfall amounts and distribution and large-scale circulation over the Huaihe river basin(30°55’—36°36’N,111°55’—121°25’E) of China.We conducted the simulation for the period of 1982-2001 and one wet year of 2003 to test the RegCM3 ensemble simulation capacity.First,by comparing both rainfall amounts and distribution simulations against the observations,it turned out that RegCM3 can capture the rainfall patterns and annual variations.In addition,the simulated spatial pattern of the 850 hPa wind vectors and specific humidity field are close to the observation,while the RegCM3 output wind speed and specific humidity are larger than observation.Finally,the ensemble simulation of RegCM3 for the 2003 summer cannot capture the spatial center of the precipitation anomalies and underestimated the magnitude of the anomalies.