高原季节转换时期大气环流变化特征

利用1961～ 2007年NCEP/NCAR的再分析逐日资料,分析高原主体上空大气环流的季节变化和受到高原影响的东亚大型环流系统的季节变化,以此证明本文得到的“高原普适性划分方法”的合理性.得到的初步结论概括如下：高原主体上空的位势高度、风场、高空温度、降水的季节变化和高原普适性季节划分方法划分的高原四季变化一致,高原南亚高压、副热带高压、副热带西风急流的三个特征指数季节变化和高原普适性季节划分方法划分的高原四季变化一致,这些结论都说明高原普适性季节划分方法划分的高原四季是合理的;风场季节率（500hPa、100hPa）显著区随高度升高向赤道靠近,风场季节率的变化主要和东亚季风的变化有关,大气环流系统季节率的显著说明了大气环流的季节变化,同时也证明了高原普适性季节划分方法的合理性.

The Change Features of Atmospheric Circulation in Seasonal Transition Period

Using the data of NCAR/NCEP monthly reanalysis data from 1961 to 2007, seasonal changes of atmospheric circulation over the Tibetan Plateau and the atmospheric circulation system which has affected by Tibetan Plateau are analyzed, thus proving the reasonability of the seasonal division method. Seasonal changes of geopotential height, wind field, air tempera- ture, and rainfall over Tibetan Plateau, are consistent with seasonal changes which made by plateau universality season division method. Besides, Asia high pressure, subtropic high air pressure and subtropic westerly jet are consistent with seasonal change which made by the seasonal division method too. All of this shows the plateau universality season division method is reasona- ble. Seasonality of wind field （500hPa,100hPa）gets close to the equator with geographic height rising. Seasonality of wind field is primarily connected with change of East Asia monsoon. Seasonality of atmospheric circulation proves the seasonal change of general atmospheric circulation, and proves the reasonability of plateau universality season division method.