2017/2018年冬季北半球大气环流特征及对我国天气气候的影响  

Northern Hemisphere Atmospheric Circulation Characteristics in 2017/2018 Winter and Its Impact on Weather and Climate in China

作　　者：章大全[1] 宋文玲[1] ZHANG Daquan;SONG Wenling(Laboratory for Climate Studies,National Climate Centre,CMA,Beijing 100081)

机构地区：[1]国家气候中心,中国气象局气候研究开放实验室,北京100081

出　　处：《气象》2018年第7期969-976,共8页Meteorological Monthly

基　　金：国家自然科学基金重点项目(41730964);国家自然科学基金项目(41605078);国家重点研发计划(2017YFC1502303)共同资助

摘　　要：2017/2018年冬季,东亚冬季风强度较常年同期偏强,西伯利亚高压偏强,季内冬季风强弱转换阶段性特征显著。欧亚中高纬以经向环流为主,乌拉尔山高压脊持续发展,东亚槽位置偏西。冬季冷空气过程频繁,受其影响,冬季东北地区气温显著偏低,而高原和西南地区西部异常偏暖。对2017/2018年冬季东亚冬季风偏强的可能原因分析表明,受北太平洋年代际涛动暖位相的调制作用,2017年秋季开始的La Ni?a事件对东亚冬季风的影响相对较弱。而冬季北半球极涡持续偏弱,北大西洋海温持续偏暖,中高纬环流系统异常和海温外强迫的共同作用,是东亚冬季风偏强的重要原因。The East Asian winter monsoon（EAWM）and Siberian high（SH）were both stronger than normal during the 2017/2018 winter,with significant intraseasonal variation.The geopotential height anomalies of mid-high latitude of Eurasia were mainly occupied by meridional circulation,with strong Ural high,and westward East Asian trough.The 2017/2018 winter was marked with frequent cold air processes,low temperature in northeasten China and abnormal warmer climate in Tibetan Plateau.Diagnostic analysis of possible mechanism for strong EAWM in 2017/2018 winter indicated that,subject to the modulation of warm phase of Pacific Decadal Oscillation（PDO）,the influence of La Nina was comparatively weak.Meanwhile,the weak polar vortex of Northern Hemisphere,and continuously warm SST in north Atlantic,both associated with the strong EAWM in 2017/2018 winter.

关 键 词：东亚冬季风 La Nina 大气环流 冷空气 

分 类 号：P461[天文地球—大气科学及气象学]