全球海气耦合模式对东亚季风降水模拟的检验  

Evaluation of Precipitation Simulation in East Asian Monsoon Areas by Coupled Ocean-Atmosphere General Circulation Models

作　　者：张莉[1] 丁一汇[2] 孙颖[2] 

机构地区：[1]中国气象科学研究院,北京100081 [2]国家气候中心,北京100081

出　　处：《大气科学》2008年第2期261-276,共16页Chinese Journal of Atmospheric Sciences

基　　金：国家重点基础研究发展规划项目2006CB403604;国家自然科学基金资助项目40605020;“十一五”国家科技支撑计划课题“全球环境变化应对技术研究与示范”项目01课题“气候变化的检测和预测技术研究”

摘　　要：以CMAP(Climate Prediction Center Merged Analysis of Precipitation)月平均降水资料和欧洲中期天气预报中心(ECMWF)的40年再分析资料集ERA40为观测基础,分析了当前政府间气候变化专门委员会第四次评估报告(IPCC AR4)的17个全球海气耦合模式对东亚季风区夏季降水和环流的模拟能力。结果表明:(1)模式基本上都能够模拟出降水由东亚东南部海洋至东亚西北部中国内陆减少的空间分布特征,部分模式能够模拟出降水的部分主要模态;(2)大部分模式基本上能够模拟出中国东部陆地降水的季节进退。但同时也存在相当的差异,这包括:(1)多数模式普遍存在模拟降水量偏少、降水变幅偏小的缺陷;(2)雨带的季节推进过程与观测存在一定偏差,尤其海洋上的季节进退过程模拟较差,有的模式甚至不能模拟出东亚季风区东部海洋上大致的季节进程。因此,模式对东亚季风区降水的模拟能力还是比较有限的,需要进一步改进。多模式集合的夏季环流场以偏弱为主,不利于降水的形成,这在中国东部大陆部分比较明显。另外,空气湿度模拟值偏低、从而造成水汽输送偏弱也是导致东亚季风区夏季降水模拟偏小的原因之一。Based on the monthly precipitation data of Climate Prediction Center Merged Analysis of Precipitation （CMAP） and European Center for Medium range Weather Forecasting （ECMWF） 40-year reanalysis data（ERA40）, the abilities of 17 Coupled Ocean- Atmosphere General Circulation Models （CGCMs） from Intergovernmental Panel on Climate Change （IPCC） Fourth Assessment Report （AR4） to simulate precipitation and circulation in East Asian summer monsoon regions are evaluated. The results show that （1） most of the models can reproduce the basic precipitation pattern that precipitation decreases from the ocean in the southeastern part of East Asia to the inland of China in the northwestern part of East Asia; （2） most of the models also can generally capture the advance of rain belt in eastern China. However, there are still considerable differences, which are （1） the climatic mean values and variability of rainfall in most models are much less than observation; （2） there is bias in the simulation of advance and retreat of rain belt, especially over the ocean, and some models even cannot capture the basic seasonal progress over the eastern ocean. Therefore, the current CGCMs have limited capability to simulate precipitation in East Asian monsoon areas, and need to be further improved. The multi-model ensemble shows that the simulated circulation intensity in summer is weaker than observation, which may restrain the development of deep convection and be unfavorable for the occurrence of precipitation, especially in the eastern part of China. Furthermore, low moisture content and related weak moisture transport may be one reason that results in the underestimate of summer precipitation in East Asian monsoon areas in the models.

关 键 词：全球海气耦合模式 季风降水 模拟 检验 

分 类 号：P426.6[天文地球—大气科学及气象学]