中国冬半年区域持续性低温事件的前期信号

Precursors of Regional Prolonged Low Temperature Events in China during Winter Half Year

大气变量物理分解的方法应用于寻找中国区域持续性低温事件的前期信号。1960～2008年的冬半年期间,总数115次强的区域持续性低温事件的对流层低层出现了天气尺度温度的负值扰动,而在对流层中高层至平流层出现了天气尺度位势高度的负值扰动。其中,112次事件分别在850hPa和300hPa上出现了温度扰动负值中心和位势高度扰动负值中心。追踪850hPa层的温度扰动能够提前5～9天预示中国区域持续性低温事件的出现。

The method of physical decomposition of atmospheric variables was used to find possible precursors to indicate regional prolonged low temperature events in China.During the winter half years for 1960-2008,a total of 115 strong events had negative temperature transient anomalies in the lower troposphere and negative geopotential height transient anomalies from the middle-high troposphere to the stratosphere simultaneously.Among them,112 events occupied the negative center of temperature transient anomalies on the 850 hPa level and the negative center of geopotential height transient anomalies on the 300 hPa level,respectively.The negative center of temperature transient anomalies on the 850 hPa level can be traced as precursors to indicate the occurrence of regional prolonged low temperature events in China over 5-9 days in advance.