东北地区冬季气温与北极涛动年代际关系研究

利用中国160站气温资料、北极涛动指数资料及关国NCEP／NCAR再分析资料中月平均海平面气压场、高度场、风场资料，分析了东北地区冬季气温、冬季北极涛动的年代际特征及其关系。结果表明：在年代际时间尺度上，两者之间存在显著正相关。冬季北极涛动处于低（高）指数期，东北冬季气温为持续冷冬（暖冬）期。可能影响机制是：在地面，冬季北极涛动处于低（高）指数期时，西伯利亚高压增强（减弱），亚洲大陆偏北冬季风增强（减弱），东北为持续冷冬（暖冬）期；在对流层中层，冬季北极涛动处于低（高）指数期时，东亚大槽加深（减弱），贝加尔湖以西以北脊增强（减弱），环流呈经向（纬向）型发展，东北对流层中层偏北风增强（减弱），东北为持续冷冬（暖冬）期。

Decadal Relationship between Winter Air Temperature in Northeast China and Arctic Oscillations

The decadal features of winter air temperature in northeast China and winter AO index and their relationship are investigated by using the monthly air temperature data at 160 stations in China,the AO index and the NCEP\NCAR reanalysis data.The analysis results show that they bear a significantly positive relationship on a time scale of decade.When the winter AO index was in a low(high) phase,the winter air temperature in northeast China underwent a successive cold(warm) winter.The possible mechanism through which the winter AO influences winter air temperature in northeast China is that at the ground surface when the winter AO index is in a low(high) phase,the Siberia high is strengthened(weakened),the winter monsoon over the East Asia is also strengthened(weakened),and northeast China undergoes a successive cold(warm) winter;and in the middle troposphere,when the winter AO is in its low(high) phase,the East Asia trough is strengthened(weakened),the ridge west and north of Baikal Lake is also strengthened(weakened),the circulation develops meridionally(zonally),the northerly wind is strengthened(weakened),and northeast China undergoes successive cold(warm)winter.