21个气候模式对东亚夏季环流模拟的评估Ⅰ:气候态

Evaluation of summer circulation simulation overEast Asia by 21 climate models.Part Ⅰ:Climatology

利用欧洲中期天气预报中心的40 a再分析资料(ERA40),评估了参与政府间气候变化专门委员会第四次评估报告(IPCC AR4)的21个全球海气耦合模式对东亚地区夏季大气环流气候态的模拟能力。结果表明:(1)尽管各模式模拟性能差异较大,但模式对东亚地区海平面气压场(SLP)、850 hPa风场及500 hPa位势高度场的气候态均有较好模拟;整体来说,500 hPa位势高度场模拟效果最好,SLP场模拟相对较差;(2)SLP在高原上模拟存在明显不足;多数模式能较好模拟850 hPa纬向、经向风场的基本特征;500 hPa位势高度场各模式模拟偏差一致性的区域性差异不明显;(3)模式对东亚地区夏季两大环流系统模拟整体偏弱,西太平洋副热带高压模拟明显偏弱。

Based on European Center for Medium range Weather Forecasting（ECMWF） 40 a reanalysis data（ERA40）,the capabilities of 21 Coupled Ocean-Atmosphere General Circulation Models（CGCMs） from Intergovernmental Panel on Climate Change（IPCC） Fourth Assessment Report（AR4） to simulate the climatology of summer atmospheric general circulations in East Asia have been evaluated.Results show that：（1） Despite large differences among 21 models,the basic spatial patterns of the climatology of SLP,U,V wind and 500 hPa geopotential height are well simulated.On the whole,the simulation of 500 hPa potential height is the best,but the simulation of SLP is relatively poor;（2） The simulated SLP exhibits evident deficiency.Most of models can simulate 850 hPa U,V wind very well,on the average,the correlation coefficient of U with ERA40 is better than that of V.There are no obvious differences in the simulated 500 hPa geopotential height;（3） On the whole,the simulated climatology of the main circulation systems is weaker than ERA40,and the simulated western Pacific subtropical high is systematically weaker than the observation.