山东冷暖冬划分及其与ENSO的关系

Division of Cold and Warm Winter in Shandong Province and Its Relationship with ENSO

基于1961—2020年山东省122站逐月平均气温资料、NOAA逐月海表温度资料以及NCEP/NCAR再分析大气环流资料,对山东强弱冷暖冬年进行了划分,分析了ENSO对山东冬季气温变化的影响。结果表明:山东冬季气温上升趋势明显,在20世纪80年代中期由偏冷阶段进入偏暖阶段,近年波动明显;去趋势项后,59 a中出现4个强暖冬、15个弱暖冬,7个强冷冬、14个弱冷冬,暖冬主要集中在20世纪90年代及以后,冷冬主要出现在20世纪60—80年代和21世纪00年代中期以后。强暖冬多出现在厄尔尼诺结束年,弱暖冬多出现在厄尔尼诺发展年,强冷冬多出现在强拉尼娜年,弱冷冬多出现在弱拉尼娜年。强弱冷暖冬年Nino1+2区平均海温距平演变较中部变化更为明显。在暖(冷)海温事件的不同阶段和强度背景下,欧亚中高纬呈现不同的纬(经)向环流特征,对应山东出现不同等级的暖(冷)冬。欧亚中高纬偏西风异常、赤道太平洋西风异常、中纬度太平洋东风异常对应山东暖冬;反之,山东为冷冬。

Based on the monthly mean temperature data of 122 stations in Shandong Province from1961 to 2020,NOAA monthly sea surface temperature data and NCEP/NCAR reanalysis atmospheric circulation data,the strong/weak cold and warm winter years in Shandong Province were divided,and the influence of ENSO on winter temperature in Shandong Province was analyzed.The results indicated that the total temperature rose obviously,from cold phase to warm phase in the mid-1980s,and it fluctuated obviously in recent years.After removing the trend,there were 4 strong warm winter years,15weak warm winter years,7 strong cold winter years and 14 weak cold winter years in the 59 years.The warm winter years were mainly concentrated in the 1990s and beyond,while the cold winter years mainly appeared from the 1960s to the 1980s and after the mid-2000s.Strong warm winters tended to occur in the end years of El Ni?o,weak warm winters tended to occur in the development years of El Ni?o,strong cold winters tended to occur in strong La Ni?a,and weak cold winters tended to occur in weak La Ni?a.In strong and weak cold and warm winters,the evolution of mean SST anomaly in Nino1+2regions were more obvious than that in the central part.Under the background of different stages and intensities of warm(cold)SST events,the middle and high latitudes of in Eurasian fields presented different latitudinal circulation characteristics,corresponding to different grades of warm(cold)winters in Shandong Province.Abnormal west wind in middle and high latitudes of Eurasia,the equatorial Pacific westerly wind anomaly and the mid-latitude Pacific easterly wind anomaly corresponded to the warm winter in Shandong,whereas it corresponded to the cold winter in Shandong.