摘要:利用NCEP/NCAR再分析资料和国家气象信息中心整编的425站气温资料，借助经验正交函数分解（EOF）、相关分析和回归分析等方法探讨1956~2015年冬季北极及中高纬度近地面温度、西伯利亚高压的变化特征以及两者与中国东部气温直接和间接的年际联系。为此定义了3个西伯利亚高压指数，即西伯利亚高压中心强度指数（SHCI）、西伯利亚高压面积指数（SHA）和西伯利亚高压东边界指数（SHEB）。结果表明：从1998年开始冬季巴伦支海、喀拉海迅速增温，并在年际尺度上与中国东部气温存在显著的负相关关系，即北极近地面温度与中国东部气温的直接联系。同时，西伯利亚高压的3个指数也与北极地区近地面温度和中国东部气温有较好的年际关系，体现了西伯利亚高压是联系北极和东亚气候的桥梁，当北极近地面温度升高（降低）时，西伯利亚高压中心强度增强（减弱），面积扩大（缩小），东边界东伸（西退），中国东部气温降低（升高），即北极近地面温度（西伯利亚高压）与中国东部气温的间接（直接）联系。最后，讨论了北极近地面温度变化影响中国东部气温的可能物理机制。
关键词:北极变暖/
西伯利亚高压/
中国东部气温
Abstract:Based on the NCEP/NCAR monthly reanalysis dataset and air temperature observations collected at 425 stations in China that is provided by the National Meteorological Information Centre, the spatial and temporal variations of the Siberian high and near-surface temperature over the Arctic and the middle-to-high-latitude region, and their direct and indirect interannual relationships with the air temperature over eastern China in the winter from 1956 to 2015 are explored using Empirical Orthogonal Function (EOF), correlation, and regression analyses, etc. For the above purpose, three Siberian high indexes are defined, including the Siberian high central intensity (SHCI), the Siberian high area (SHA) and the Siberian high eastern boundary (SHEB). The results show that the near-surface warming in the Barents-Kara Sea has rapidly increased in winter since 1998 and presents a significant negative interannual correlation with air temperature in eastern China. This relationship is named as the direct connection between the Arctic and eastern China in the present study. Meanwhile, the interannual associations between the above three indexes and the near-surface temperature over the Arctic and eastern China are significant in winter, suggesting that the Siberian high is a bridge linking the Arctic and East Asian climate to some extent. When the Arctic near-surface temperature increases (decreases), the intensity of the Siberian high enhances (weakens), its coverage expands (shrinks), its eastern boundary extends further eastward (retreats westward), and the temperature decreases (increases) in eastern China. The above relationship is called indirect connection between the Arctic and Eastern China in the present study. Finally, the possible physical mechanisms for the influences of Arctic near-surface temperature on eastern Asia temperature are discussed.
Key words:Arctic warming/
Siberian high/
Eastern China air temperature
PDF全文下载地址:
http://www.iapjournals.ac.cn/qhhj/article/exportPdf?id=20180407
