夏季副热带西部模态水异常与我国秋、冬季气温年际变化的关系  

Relationship between the North Pacific Subtropical Mode Water Anomaly in Summer and the Interannual Change of Autumn-Winter Air Temperature over China

作　　者：常蕊[1,2] 张庆云[1] 李荣凤[1] 

机构地区：[1]中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室,北京100029 [2]中国气象局公共气象服务中心,北京100081

出　　处：《气候与环境研究》2010年第3期303-310,共8页Climatic and Environmental Research

基　　金：国家科技支撑计划课题2009BAC51B02;中国科学院知识创新工程重要方向项目KZCX2-YW-218;国家自然科学基金项目40975022;40776011

摘　　要：利用合成、回归等方法分析了夏季副热带西部模态水(简称STMW)异常与我国秋、冬季气温年际变化的联系,发现:1)秋、冬季东亚—太平洋地区的大气环流异常对我国的气温变化起了重要作用,夏季STMW异常通过东亚—太平洋地区的大气环流异常进而与我国秋、冬季的气温变化联系在一起。2)夏季ST-MW正(负)异常时,同年秋季我国西北、东北和江淮地区的气温异常偏低(偏高);冬季时,东北、西北地区气温偏高(低)。3)这种联系主要是通过东亚—太平洋地区大气环流的典型分布实现的:夏季STMW异常偏强(弱)时,同年秋季与黑潮附近的冷(暖)海温相对应,西北太平洋上空大气环流出现负(正)的高度距平,气旋性(反气旋性)环流西侧的偏北(南)气流引导(阻碍)东亚大陆中高纬冷空气南下,同时东欧地区的高压(低压)向东南方向伸展,对我国西北地区秋季冷空气的活动起到了增幅(削弱)作用,我国东北、西北和江淮大部分地区的冷空气活动偏强,气温普遍偏低(高)。黑潮区附近的冷(暖)海温持续热力作用下,海洋不断得到(失去)热量,积累到冬季,促使黑潮区域的海表面温度(SST)逐渐向正(负)异常转变。冬季的大气环流场也对应发生调整:西北太平洋上空出现显著的高压(低压)异常,反气旋(气旋)西侧的偏南(北)气流减弱(加强)了我国东北地区的冷空气强度,气温偏高(低);亚洲中纬度地区受低压(高压)距平控制,我国西北地区的冷空气活动较弱(强),气温偏高。Based on the NCAR/NCEP reanalysis and ERA-40 datasets, the relationship between the North Pacific subtropical mode water （STMW） and the interannual chmage of autumnwinter air temperature over China was revealed by using composite and correlation （regression） analysis. It was found that the relationship between the autumn- winter air temperature over China and the summer STMW intensity was linked by the anomalous patterns of the Asian - Pacific atmospheric circulation and the sea surface temperature （SST） anomalies over the collocated reemergence area of STMW （20°N- 27°N, 125°E- 150°E）, that is the Kuroshio area. The main conclusions are： 1） The strong summer STMW is usually accompanied by the low air temperature over the northwestern and nortbeastem parts of China and the Changjiang- Huaihe valley during autumn; and the high air temperature over the northwestern and northeastern parts of China during winter, and vice versa. 2） A possible process that links the summer STMW with the autumn- winter air tempera- ture is also revealed. First of all, the authors pointed out that the summer STMW anomaly can impose an effect on the thermocline depth and the SST anomaly over the Kuroshio area during autumn. The strong summer STMW is usually companied by the shallow thermocline depth and negative SST anomalies over the Kuroshio area during autumn and positive SST anomalies during winter, and vice versa. 3） In the strong summer STMW cases, the anomalous northerly to the western flank of the anomalous cyclone, which is corresponding to the autumn cold SST over the collocated reemergence area, guides the cold air to China, meanwhile, the anomalous cold high pressure over eastern Europe extents southeastward, leading to the low air temperature over the northwestern and northeastern parts of China and the Changjiang-Huaihe valley during autumn. Affected by the continuous accumulation of the endothermic process over the cold SST area in autumn, the positive SST anomaly emergences over the Kuroshio are

关 键 词：副热带西部模态水秋、冬季气温 黑潮附近海表面温度 亚洲大气环流 

分 类 号：P461[天文地球—大气科学及气象学]