中国北方冬季气温的年际变化对北太平洋东部海温异常的响应

利用地面气温观测资料及NCEP/NCAR逐月再分析资料，分析了中纬度北太平洋东部海温异常变化对中国北方地区冬季气温的可能影响。结果表明，前期夏、秋季中纬度北太平洋东部海温与北方地区冬季气温存在持续稳定的正相关关系，并且这种相关性在年代际尺度上较年际尺度更为显著。这种联系与中纬度北太平洋东部关键区海温在对流层中低层激发出的一种类似北美—大西洋—欧亚遥相关型波列有关。当前期关键区海温偏高（低）时，其激发的波列使得乌拉尔山阻塞高压偏弱（强），西伯利亚高压偏弱（强），导致贝加尔湖以南大部地区受正（负）高度距平控制，亚洲地区中高纬以纬（经）向环流为主，有利于北方大部地区气温偏高（低）。研究表明，中纬度北太平洋东部海温异常通过激发出一个从关键海区到我国北方地区的跨越东西半球的遥相关型波列，引发北半球中高纬度大气环流异常，进而影响北方冬季气温。

Impact of the Sea Surface Temperature Anomaly in the Eastern North Pacific on Interannual Variations of Winter Temperature in Northern China

Based on monthly temperature observations collected at meteorological stations and the NCEP/NCAR monthly reanalysis data, possible impacts of sea surface temperature anomaly (SSTA) in the mid-latitude eastern North Pacific (MENP) on winter temperature in northern China are studied. The results are as follows. There is a stable positive relationship between winter temperature in northern China and SSTA in the preceding summer and autumn in the MENP, and the correlation is more significant on interdecadal scale than on interannual scale. This relationship is associated with a kind of wave pattern analogous to the North America-Atlantic-Eurasia wave train pattern in the middle and lower troposphere triggered by SSTA in preceding autumn in the MENP. When the SSTA in preceding autumn over the MENP is higher (lower), the wave train pattern makes the Ural blocking and Siberian high weaker (stronger). At the same time, most regions to the south of the Baikal Lake are controlled by positive (negative) 500-hPa geopotential height anomaly. These factors lead to dominant zonal (meridional) circulation over the Asian region and cause higher (lower) temperature over most regions of northern China. The present study reveals that the wave train pattern from the Western Hemisphere to the Eastern Hemisphere can be triggered by SSTA in the MENP. This wave train can influence general circulation in northeastern Asia and ultimately affect temperature in northern China.