中国东部冬季气温变化的主要区域空间模态及其与大气环流的关系  

Main regional spatial modes of winter air temperature variations in eastern China and their relationship with atmospheric circulation

作　　者：陈金琪 范灵悦 高晶[1] CHEN Jinqi;FAN Lingyue;GAO Jing(Inner Mongolia Climate Center,Hohhot 010051,China)

机构地区：[1]内蒙古自治区气候中心,内蒙古呼和浩特010051

出　　处：《冰川冻土》2024年第3期876-890,共15页Journal of Glaciology and Geocryology

基　　金：中国气象局数值预报统筹研发专项(TCYF2024QH005);内蒙古自治区自然科学基金项目(2022LHMS04004);内蒙古气象科技创新项目(nmqxkjcx202335)资助。

摘　　要：本文利用1956—2017年我国519个站点逐日气温资料,通过旋转经验正交函数分析方法得到了近62年我国冬季气温变化主要的区域空间模态,研究了其与大气环流的关系,并进一步使用2018—2023年上述站点冬季气温资料进行验证分析。结果表明,我国冬季气温变化有两个较为稳定的区域空间模态:第一模态主要表现为南方大部分地区出现异常低温,低温极值区位于华南和东南沿海区,称之为南方型;第二模态的气温异常信号主要集中在东北地区,称之为东北型。其中,南方型模态与赤道中太平洋的海温呈显著负相关关系,与东亚冬季风的“南北反向”模态呈显著正相关。当冬季赤道中太平洋海温异常偏冷时,东亚南部地区表现为强烈的低层偏北风距平,北方则无显著偏北风距平,造成南方大部分地区出现异常低温。冬季北极涛动与东北型低温模态有显著联系,当北极涛动呈负位相时,冷高压主要集中在极区,高压东侧盛行东北风,造成东北地区冬季气温异常偏低。近6年中,2018年与2021年冬季呈东北型低温模态,其关键环流系统接近北极涛动负位相,验证了该结论。Based on the daily air temperature data of 519 stations in China from 1956 to 2017,this paper dis-plays two main regional spatial modes of winter surface air temperature anomalies in eastern China through the rotating empirical orthogonal function analysis method,and studies the relationship between them and atmo-spheric circulation.The results show that these two regional spatial modes are relatively stable.The first mode is manifested as the anomalous low temperature in most parts of southern China,which is called southern mode.The extreme cold centers of this mode are located in the south and southeast coastal areas.The anomalous tem-perature signals of the second mode are mainly concentrated in the northeast China,which is called the northeast mode.There is a significant negative correlation of the time series of southern mode with sea surface temperature in the equatorial central Pacific,and a significant positive correlation with the opposite variation mode of East Asian winter monsoon in the south and north,respectively.When the sea surface temperature in the equatorial central Pacific is anomalously cold in winter,the southern part of East Asia shows a strong low-level northerly wind causing anomalously low temperature in most parts of southern China.At this time there is no significant northerly wind anomaly in the northeastern Asia.By contrast,the winter Arctic Oscillation is significantly relat-ed to the northeast low-temperature mode.When the Arctic Oscillation is in its negative phase,the cold high pressure is mainly concentrated in the polar region,and the northeasterly wind prevails on its east side,leading to anomalously low winter air temperatures in Northeast China.

关 键 词：冬季气温 空间型态 东亚冬季风“南北反向”模态 北极涛动 

分 类 号：P468.021[天文地球—大气科学及气象学]