近40多年四川盆地降温与热带西太平洋海温异常的关系

The Relationship between the Cooling of Air Temperature in Sichuan Basin and the Anomalies of SST over Tropical Western Pacific during the Last More Than 40 Years

应用滑动滤波技术， 分析了半个世纪以来， 四川地区温度变化及其与西太平洋海温的关系。结果表明， 四川盆地气温在７０ 年代中期发生了一次突变， 由偏暖阶段进入偏冷阶段。其中， ５０ 年代最暖， ８０ 年代最冷， 这种偏冷趋势在夏季最显著； 热带西太平洋海温同样在７０ 年代中期发生了一次突变， 由偏暖阶段进入偏冷阶段， 也是５０ 年代最暖， ８０ 年代最冷， 这种偏冷趋势同样在夏季最显著； 热带西太平洋海温在变化趋势上与四川盆地气温变化具有同位相关系； 热带西太平洋海温异常偏暖（ 冷） ， 引起西太平洋副高位置偏西（ 东）偏北（南） ， 造成四川盆地气温异常偏暖（ 冷） ； 热带西太平洋海洋热状况的变化， 通过影响西太平洋副高等环流系统变化是造成四川盆地气温异常的重要原因之一。

Based on the moving filter method, the variation of temperature in Sichuan and its relationship with SST over tropical western Pacific during the last half century are analyzed. The result shows that the abrupt change of temperature from warm to cold in Sichuan Basin occurs in the middle 1970′s. The warmest decade is the 1950′s and the coldest one is the 1980′s. This cooling tendency is most obvious in summer. And the SST over tropical western Pacific has also an abrupt change from warm to cold in the 1970′s. The warmest decade is also the 1950′s and the coldest one is also the 1980′s. This cooling tendency is also most obvious in summer. The characteristics of both the SST and the air temperature variations are in phase. The positive (negative) anomalies of SST over tropical western Pacific, resulting in the location of Subtropical High over the western Pacific to the west and north (east and south), then brings the warmer (colder) anomalies of temperature in Sichuan Basin. The effect of thermal regime of tropical western Pacific, by influencing the variations of general circulation such as the location of subtropical high, is one of the important reasons for the variation of air temperature in Sichuan Basin.