【作者】 黄山江；

【导师】 王谦谦；

【作者基本信息】 南京气象学院 ， 气象学， 2004， 硕士

【摘要】 在西北春季和夏季降水气候特征分析的基础上，本文着重探讨了西北春季和夏季降水异常以及对应的大气环流异常进行了研究，并分析了赤道中东太平洋的海温异常对我国西北地区春季和夏季降水的影响。 用EOF分析方法选取西北地区29个代表站，分别对其春季和夏季近50a降水进行年际变化和年代际变化时空特征分析，结果发现(1)西北地区近50a降水时空趋势变化以103°E为基准线，以西为正，以东为负，并有准3a的振荡周期，80年代中期西北地区春季降水出现了气候突变。(2)西北地区多、少雨与500hPa高度场和副热带高压的位置和强弱密切相关，并且与极涡、南亚高压关系密切。(3)西北地区春季降水异常与同纬度的地区相关最好，与东北中部地区反相关；夏季多雨，则远离海洋的内陆多雨，夏季少雨，则沿海及近海多雨。(4)西北地区春季降水与赤道中东太平洋海区，尤其是Key海区(125W°～85°W、5°S～10°N)海温(前年8～9月平均)有较好的正相关关系。(5)西北地区夏季降水与赤道中东太平洋海区，尤其是Key海区(150°W～110°W、15°S～5°N)海温(前年7～9月平均)有较好的正相关关系。(6)通过SVD分析，发现西北地区春季和夏季降水与相对海温关键区有较好的耦合正相关。更多还原

【Abstract】 Based on the analysis of the Northeast China precipitation character, thispaper is particularly concerned with the corresponding general circulation anomalies character of the Precipitation in Spring and in Summer in Northwest China and the influence of SSTA in middle-east equator Pacific Ocean .29 representative stations of Northwest China are selected using EOF analysis, and the detailed results of characteristics are given for temporal and space variation of interarmual change and decadal change. The main conclusions are followed:(1) the tendency of precipitation in northwest China is positive to the west of 103°E longitude and opposite to the east of it. There is a periodic oscillation of quasi-three years of precipitation and a mutation in the middle of 80s in spring precipitation of northwest China.(2) It indicates the close relationship between wet, dry phase and the position, amplitude of 500hPa high field and subtropical high. And there are close relation with polar vortex ,south Asia high field.(3) The spring precipitation anomalies are close relation with the same attitude areas, and negative correlation with Northeast ones. If there are much rain in summer, then the lands which are from sea are rainy, otherwise the areas nearly sea are rainy.(4) There is a apparent positive correlation between spring precipitation in northwest China and SSTA(8~9 monthly averaged in former year)in middle-east equator pacific Ocean, especially the higher correlation in the ’Key regions’ (125° W~85°W\ 5°S~10°N) .(5) There is a apparent positive correlation between summer precipitation in northwest China and SSTA(7~9 monthly averaged in former year)in middle-east equator pacific Ocean, especially the higher correlation in the ’Key regions’ (150° W~110°W, 15°S~5°N) .(6) There is a positive couple correlation between spring and summer precipitation in northwest China and SSTA by SVD analysis.更多还原