辽宁冬季气温变化特征及与东亚冬季风的关系

摘要

Based on the monthly mean temperature data from 53 observational stations in Liaoning province during 1961 to 2012 and the NCEP/NCAR reanalysis data such as the monthly mean height field,wind field and sea sur-face pressure,the spatial and temporal features of the winter air temperature were analyzed.The previous defini-tions of six East Asian winter monsoon indexes were reviewed and calculated,and the relationships of winter air temperature in Liaoning province with the six indexes were compared.The results show that the mean variance of winter air temperature is greater in the eastern region than in the western region during 1961 to 2011,and it is in a significant positive trend in most regions of Liaoning province.The first pattern of EOF shows that winter air tem-perature in Liaoning province is abnormal high or low.The time coefficient is in a significant increasing trend and the abrupt change occurs in 1977.There are cycles of 4.5 years,2.0 years and 3.0 years for winter air temperature in Liaoning province.The East monsoon index defined by Zhu has the best relationship with winter air temperature in Liaoning province regardless of the abrupt change time,periodic characteristics,correlation coefficients and in-verting corresponding relations.The relationship can be clearly explained in 850 hPa meridional wind field and sea surface pressure field.%采用1961-2012年辽宁省53站月平均气温资料及NCEP/NCAR再分析月平均高度场、风场和海平面气压场资料，分析近51 a辽宁冬季气温的时空变化特征。在归纳并计算前人定义的6种东亚冬季风指数的基础上，对比辽宁冬季气温与6种东亚冬季风指数的关系。结果表明：1961-2011年辽宁东部冬季气温均方差大于西部，全省绝大部分地区为显著的正趋势；辽宁冬季气温EOF第一模态表现为全省一致异常偏高或偏低的特征；时间系数显著上升，在1977年发生突变；并存在4.5、2.0a和3.0a的周期变化；朱艳峰定义的东亚冬季风指数是各指数中与辽宁冬季气温变化关系最密切的指数，无论从突变时间、周期特征、相关系数还是反位相对应关系上，其均与辽宁冬季气温关系最密切，且850 hPa经向风场和海平面气压场也能说明二者有较好的对应关系。