蒙古高压一组环流指数及与中国同期气候异常关系分析  

A GROUP OF CIRCULATION INDICES OF MONGOLIA HIGH AND ANALYSIS OF ITS RELATIONSHIP WITH SIMULTANEOUS ANOMALY IN THE CLIMATE OF CHINA

作　　者：刘晴晴[1,2] 王盘兴[1] 徐祥德[3] 智海[1] 孙晓娟[1] 

机构地区：[1]南京信息工程大学,江苏南京210044 [2]中国气象局广州热带海洋气象研究所,广东广州510080 [3]中国气象科学研究院,北京100081

出　　处：《热带气象学报》2011年第6期889-898,共10页Journal of Tropical Meteorology

基　　金：科技部国家科技支撑计划课题(2008BAC48B02);江苏省研究生培养创新工程创新计划项目(CX08B_016Z)共同资助

摘　　要：定义了一组描述冬季（12—2月）的月、季1 000 hPa等压面上蒙古高压（MH）状态的新的环流指数,它包括面积指数S、强度指数P、中心位置指数（λc,φc）。用NCEP/NCAR资料计算了1948/1949—2007/2008年60个冬季的月、季MH的上述环流指数。用它们分析了近60年冬季各月MH的气候态,表明MH在12、1月最强,2月明显减弱;12月偏南,1、2月逐渐北移。分析了MH强度P和中心位置（λc,φc）的年代际变化特征及其与中国冬季气候（气温、降水）的相关,结果表明：（1）MH强度P和中心位置指数φc均存在显著年代际变化,P在1960′s末—1970′s初由高转低,φc在1970′s末—1980′s初由偏北转偏南。12、2月P~φc间存在显著正相关。MH强年偏北、弱年偏南。（2）MH环流指数P、φc与中国同期气温存在显著负相关,P的显著负相关区覆盖了中国除西南外的大部分区域,φc的显著负相关区也覆盖了中国东部除东南沿海外大部分区域;它们与中国降水的同期相关联系远弱于气温。（3）全球增暖背景下MH强度减弱、中心南移,中国大部分地区出现持续暖冬;但1990′s末以来,相反的异常时有发生。（4）＂0801华南雪灾＂期间（2008.1.10—2.2）MH异常偏强,并有四次中期活动过程;它们是造成此次极端气候异常事件的直接环流原因。A set of new circulation indices are defined to characterize monthly and seasonal Mongolia high at the 1 000 hPa geopotential height in winter.They include the area（S）,intensity（P） and center position（λc,φc）indices.These indices,calculated by use of 1948/1949-2007/2008 NCEP/NCAR data from 1948 to 2007（or a total of sixty winters）,are used to investigate the climate characteristics of the Mongolia high.Results show that the high is the strongest（largest） in December and January,obviously weakening（becoming smaller） in February.It lies south of the normal position in December and moves northward gradually in January and February.The anomalies of intensity（P） and center position（λc,φc） of the Mongolia high,together with their correlation with Chinese winter temperature and precipitation,are studied.Results show that（1） the intensity and center position indices show distinct interdecadal variations,which decreased at the end of the 1960 ′s and the beginning of the 1970s,with φc moving from north of the normal position to south of it.There is significant positive correlation between P and φc.When MH is stronger,the position is more northward and vice versa.（2） There is notable negative correlation between P,φc and Chinese temperature of the corresponding period respectively,with large areas,except for the southwest of China,covered by a notable negative correlation of P,and the east of China,except for southeast coastal region,covered by a notable negative correlation of φc.Whereas,their relationship with precipitation in the corresponding period is far weaker than that with temperature.（3） Under the background of global warming,the Mongolia high weakens and its center moves southward,along with the persistent warm winter that takes place over large parts of China.However,opposite anomalies often occurred since the 1990 ′s.（4） The January 2008 southern China snow disaster showed mainly persistent low temperatures and the Mongolia high strengthened and its cen

关 键 词：蒙古高压 环流指数 蒙古高压异常 中国冬季气候异常 “0801华南雪灾” 

分 类 号：P434.4[天文地球—大气科学及气象学]