嘉善县降水与厄尔尼诺和拉尼娜现象的关系

The Relationship Between Precipitation and El Nino or La Nina Events in Jiashan

通过研究分析1971—2020年嘉善县降水与厄尔尼诺和拉尼娜事件的关系可知,当发生厄尔尼诺事件时,嘉善县降水较常年偏少的概率更高,冬、夏季降水距平变化较春季更加明显,其中秋季降水正距平变化最明显。厄尔尼诺年时,冬季降水变化具有年代际特征,2000年以前降水较常年基本上偏少,之后则偏多。当发生拉尼娜事件时,嘉善县秋冬季降水量较常年偏多的概率更高,春夏季则相反,且冬、夏、秋季降水距平变化较春季更加明显。同时,嘉善县降水偏少的概率基本上集中在40%~60%,其中拉尼娜年春季嘉善降水偏少的概率稍高。通过皮尔逊x^(2)拟合方法检验可知,嘉善县降水与厄尔尼诺及拉尼娜现象间的线性相关不显著,即二者相互独立。

In this study,we analyzed the relationship between precipitation in JiaShan and El Nino or La Nina events during period of 1971-2020.The results showed the following:1)When El Nino events occurred,the probability of less precipitation than normal in JiaShan was higher,and the precipitation anomaly changes in winter and summer were more obvious than in spring,the positive precipitation anomaly changes in autumn were the most obvious.And precipitation changes in winter had a interdecadal characteristic in El nino years,the precipitation was basically less than normal before 2000,which was basically more than normal after 2000.When La Nina events occurred,the probability of more precipitation than normal during autumn and winter in JiaShan was higher,the precipitation anomaly changes during spring and summer in contrast,and the precipitation anomaly changes in other seasons were more obvious than spring.Meanwhile,the probability of less precipitation than normal in JiaShan was basically concentrated in 40%-60%,and the probability of precipitation in spring during La Nina years was more obvious.Through the Pearson test,we could see the precipitation in JiaShan was not significantly correlated with El Nino or La Nina events,they were independent.