厄尔尼诺/拉尼娜事件对山西省南部地区气候的影响

Effects of El Nino/La Nina Events on Climate of Southern Shanxi Province

根据1961年以来的气温和降水资料,结合小波分析和发生的厄尔尼诺/拉尼娜事件,分析了1961年以来山西省南部地区气温和降水的变化趋势、周期以及厄尔尼诺/拉尼娜(El Nino/Southern Oscillation,ENSO)事件对山西省南部地区气温、降水量以及旱涝灾害的影响。研究结果表明,1961年以来山西省南部年平均气温总体呈波动式上升,上升速率为0.34℃/10a,而年平均降水量总体呈下降趋势,下降速率为23.4mm/10a。小波周期分析显示,山西省南部气温变化的周期约为3,8,20和25a,降水量变化的周期约为3和7a。厄尔尼诺年山西省南部年平均气温升高,降水量显著减少,而拉尼娜年气温下降,降水量略有增加。该区在厄尔尼诺年易发生旱灾,而拉尼娜年易发生涝灾,且旱涝灾害多分别发生在连续性的厄尔尼诺年和拉尼娜年。

Based on observed temperature and precipitation data since 1961 in Southern Shanxi Province, the trend and periodic changes of temperature and precipitation in the area, as well as the effects of the E1 Nino/ La Nina（E1 Nino/Southern Oscillation, ENSO） events on the temperature, precipitation, droughts, and floods were analyzed using wavelet analysis. The results show that during the past sixty years, the annual temperature of the area increased at a rate of 0.34 ~C/10 a, while the annual precipitation was decreasing at a rate of 23.4 mm/10 a. The wavelet analysis on the periodic changes indicate that the periods of annual tem- perature in the area were approximately 3, 8, 20, and 25 years and that of annual precipitation were about 3 years and 7 years. Annual mean temperature in the area ascended and annual precipitation decreased signifi- cantly in El Nino years, while showed opposite trends in La Nina years. Draughts occur more often in E1 Nino years, while more floods were recorded in La Nina years. Draughts and floods mainly occur in the con- tinuous E1 Nino years and La Nina years, respectively.