大气热力强迫和动力强迫的调配及平均经圈环流的仿真模拟

通过研究平均经围环流（ＭＭＣ）及其所受的内外强迫作用的相互配置，指出对ＭＭＣ的热力和动力强迫满足确定的调配率。这一调配率受大气内在的斜压性、静力稳定度及绝对涡度制约。利用辐射加热和凝结加热参数化方案，结合欧洲中期天气预报中心（ＥＣＭＷＦ）的分析资料，对１月份平均经围环流进行数值仿真模拟。结果表明，热带对流加热可以形成双层Ｈａｄｌｅｙ环流结构；涡动动量输送对双Ｈａｄｌｅｙ环流的形成也有一定影响。中高纬度的ＭＭＣ则主要由外动量强迫及大气的动量和热量输送特征决定。

MODULATION OF ATMOSPHERIC THERMAL AND MECHANICAL FORCING AND NUMERICAL MODELING OF MEAN MERIDIONAL CIRCULATION

Upon investigating the relative locations of internal and external forcing and the resultant mean meridional circulation, it is found that thermal forcing and mechanical forcing for the formation of atmospheric mean meridional circulation are modulated by a certain ratio. This ratio is determined by the inherent baroclinity, static stability and absolute vorticity of the atmosphere.By employing a parameterization scheme for radiative heating and condensation heating, together with the analysis data of the European Center for Medium-range Weather Forecasts, the mean meridional circulation for January was simulated numerically. It was found that latent heat release in the tropics may result in the formation of double-layered Hadley circulation, so may the eddy momentum transfer processes. On the other hand, mean meridional circulations in extra-tropics are mainly determined by external momentum forcing and atmospheric properties of eddy momentum and heat transfer.