区域海气耦合过程对中国东部夏季降水模拟的影响  

Impacts of Regional Air-Sea Coupling on the Simulation of Summer Precipitation over Eastern China in the RIEMS Model

作　　者：房永杰[1] 张耀存[1] 

机构地区：[1]南京大学大气科学学院,南京210093

出　　处：《大气科学》2011年第1期16-28,共13页Chinese Journal of Atmospheric Sciences

基　　金：国家重点基础研究发展规划项目2006CB400506

摘　　要：本文以区域环境系统集成模式(RIEMS)和普林斯顿海洋模式(POM)为基础,建立了一个区域海气耦合模式,评估了其对1985～2004年中国东部夏季降水的模拟性能,并通过与观测海温强迫下单独大气模式模拟结果的比较,分析了海气耦合过程对降水模拟性能的影响。结果表明:耦合模式基本能够模拟出中国东部地区夏季降水的气候态分布及中国主要雨带的季节性进退,模拟的降水在空间分布和强度上较单独大气模式都更为合理,对华北和华南地区降水的模拟改进尤为明显。耦合模式能够较好地模拟出1985～2004年中国东部地区夏季降水主要的时空变化特征,模拟的华北、长江中下游以及华南地区夏季降水与观测的相关系数均高于单独大气模式。相比于单独大气模式,耦合海洋模式之后海洋—大气反馈过程改善了模式对海洋—大气界面热通量的模拟,使模拟的东亚地区海陆热力差异与NCEP/NCAR再分析资料结果更为一致,由此提高了耦合模式对低层风场以及水汽输送的模拟能力,从而改善了模式对中国东部地区降水的模拟。A regional air-sea coupled model is developed,which consists of the Regional Integrated Environment Model System（RIEMS） and the revised Princeton Ocean Model（POM）.Compared with the uncoupled model results and the observations,the role of air-sea interactions in the simulation of summer precipitation in eastern China from 1985 to 2004 is investigated.The results show that the regional air-sea coupled model has a good performance on simulating the mean summer precipitation and the seasonal evolution of the summer rainbelt,and the distribution and intensity of the rainband in the coupled model are more reasonable than those in uncoupled model RIEMS.The improvement of the rainfall simulation is remarkable in North China and South China.Moreover,the coupled model reproduces well the spatial and temporal distributions of summer rainfall in eastern China from 1985 to 2004.The correlation coefficients between the summer rainfalls derived from the coupled model and the observation over North China,the middle and lower reaches of the Yangtze River and South China are higher than those from uncoupled model RIEMS and the observation.Compared with the run with RIEMS,the air-sea feedbacks in the coupled model improve the simulation of the sea surface heat flux,resulting in better agreement with the NCEP/NCAR data in the land-sea thermal contrast over eastern Asia.Therefore,the monsoon circulation and the water vapor transport are better simulated,which improves the rainfall simulation in eastern China.

关 键 词：区域海气耦合模式 降水 海气相互作用 海陆热力差异 

分 类 号：P461[天文地球—大气科学及气象学]