极涡对南方电网区域降水的影响

基于国家气候中心提供的1960—2009年74项大气环流因子中提取出的极涡指数参数,并结合中国气象局整编的1960—2009年南方电网区域内95站降水月平均资料,采用相关性分析法讨论太平洋极涡和亚洲区极涡对南方电网区域降水的影响。结果表明,太平洋极涡和亚洲区极涡对南方电网区域降水的影响比较大,冬半年极涡强度指数与南方电网区域降水之间存在负相关性,极涡强度指数越小,降水越多,相关系数自西向东呈现先增大后减小趋势;春半年极涡强度指数与南方电网区域降水的相关系数自西向东先减小再增大,在四川南部和云南西部地区相关系数绝对值在0.7以上。对单个测站而言,降水量与极涡强度指数间呈负相关,且相关系数绝对值均超过0.5,其中亚洲强极涡对南方电网区域降水的影响比太平洋强极涡大。

Effect of the Polar Vortex on Precipitation in China Southern Power Grid

Using the 74 factors of the atmospheric circulation data of National Climate Center from 1960 to 2009, and monthly precipitation data from 95 stations in China provided by National Climate Center (NCC) from 1960 to 2009, the effect of the polar vortex on precipitation in China Southern Power Grid were discussed by means of correlation analysis.The results showed that the influence of Pacific polar vortex and the Asia polar vortex on the South China power grid is relatively large , and the polar vortex intensity index and the precipitation in the China Southern Power Grid is negative correlation.The smaller the polar vortex intensity index is, the more precipitation.The absolute value of cor-relation coefficient increased firstly and then decreased from the west to the east.But in spring, the correlation coefficient decreased firstly and then increased from the west to the east.In southern Sichuan and western Yunnan, the absolute value of correlation coefficient was above 0. 7.For each single station, the precipitation and the polar vortex intensity index was negatively correlated, and the absolute value of correlation coefficient was more than 0.5.The influence of the Asian strong polar vortex was greater than that of the Pacific Ocean.