东亚区域气候变化的长期数值模拟试验

文中利用NCAR的中尺度模式MM 5V3对东亚地区进行了 10a的长期积分模拟试验 ,并着重对冬、夏两季东亚区域气候变化特征进行了分析。分析结果表明 :(1)模式能够合理地模拟出 10a冬、夏平均的区域气候特征。模拟的 10a冬季平均降水的分布和强度与实际比较一致 ,对夏季降水分布特征的模拟也比较合理 ,但模拟的夏季华北降水偏多。模式对冬季平均场的模拟要优于对夏季的模拟 ;(2 )模式对降水、地面气温年际变率的模拟较为合理 ,模拟的中高层环流、温度场等要素的距平相关系数都比较高 ;(3)模式对不同ElNi no年对东亚区域气候变化影响的模拟能力有所不同 ,模拟的 1992 ,1995年的结果比较合理 ,但对 1998年模拟得不理想 ;(4)MM5V3模式具备一定的区域气候模拟能力。

LONG TERM CLIMATE CHANGE NUMERICAL SIMULATION IN EAST ASIA

A 10-year regional climate simulation was performed using the fifth-generation PSU/NCAR Mesoscale Model (MM5) driven by large-scale conditions of the NCEP/NCAR reanalyses. Winter and summer mean regional climate features were examined between simulation and observation. The results showed that : (1) the model could well simulate the 10-yr winter and summer mean circulation, temperature and moisture transfer at middle and low levels. The simulated winter and summer mean sea level pressure agreed with the NCAR/NCEP reanalysis data. The model could well simulate the distribution and intensity of winter mean precipitation rates, it also simulated the distribution of summer mean precipitation rates, but it overestimated the summer mean precipitation over North China. The model's ability to simulate the regional climate change in winter was prior to that in summer. (2) the model could simulate the inter-annual variation of seasonal precipitation and surface air temperature. The anomaly correlation coefficients of geopotential height and temperature at low and high levels between simulation and observation were high. (3) the model showed different ability to simulate the regional climate change associated with the El Nino events. It well simulated the anomaly of summer mean precipitation in 1992 and 1995, but could not simulate that in 1998 (4). The MM5V3 had the ability to simulate the regional climate change, and could be used for long term regional climate simulation.