长江中下游地区2011年冬春连旱及2013年夏季高温干旱环流特征及其与Rossby波活动的联系对比分析  

A COMPARISON OF THE ROSSBY WAVE ACTIVITIES AND CIRCULATION FEATURES OF THE DROUGHT IN WINTER-SPRING OF 2011 AND IN SUMMER OF 2013 OVER MID-LOWER REACHES OF THE YANGTZE RIVER BASIN

作　　者：许金萍 王文[2] 蔡晓军[2] 许志丽[3] 许金星 XU Jin-ping;WANG Wen;CAI Xiao-jun,;XU Zhi-li;XU Jin-xing(Anji Meteorological Bureau, Anji 313300, China;Key Laboratory of Meteorological Disaster,Ministry of Education （KLME）/Joint International Research Laboratory of Climate and Environment Change （ILCEC）/ Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster （CIC-FEMD）, Nanjing University of Information Science and Technology,Nanjing 210044, China;Inner Mongolia Meteorological science Institute, Hohhot 010051, China;Dunhua Meteorological Bureau, Dunhua 133700, China)

机构地区：[1]安吉县气象局,浙江安吉313300 [2]南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作实验室/气象灾害预报预警与评估协同创新中心,江苏南京210044 [3]内蒙古气象科学研究所,内蒙古呼和浩特010051 [4]敦化市气象局,吉林敦化133700

出　　处：《热带气象学报》2017年第6期992-999,共8页Journal of Tropical Meteorology

基　　金：国家自然科学基金(41275091)资助

摘　　要：利用1981—2013年NCEP/NCAR逐日再分析资料及OISST海温月资料,对长江中下游地区2011年冬春连旱及2013年夏季高温、干旱事件的形成机制进行对比分析。结果发现两次干旱事件:(1)均受偏强东亚季风影响,导致冷暖气流无法交汇于长江流域;(2)赤道太平洋海温距平均呈现"西正东负",加强Walker环流的同时引发局地Hadley环流异常,致使长江流域上空长期受异常下沉气流控制;(3)均与大西洋的Rossby波有关:2011年冬春,受NAULEA遥相关型影响,Rossby波能量向东频散至亚欧大陆东部及太平洋地区堆积,使东亚大槽长期维持在120°E附近,加强东亚冬季风;2013年夏季,受同为负位相的"silk road"及EAP遥相关型共同作用,源自北大西洋的Rossby波能量能够影响到东亚-太平洋地区,致使西太副高异常西伸,加强东亚夏季风。Using the daily NCEP/NCAR reanalysis dataset and monthly OISST sea surface temperature data from 1981--2013, the formation mechanism of drought eventsin winter-spring 2011 and summer 2013 in the middle and lower reaches of the Yangtze River Region （MLRYR） is investigated. The results show that both the drought events have the following common points： （1） they were both affected by a strong East Asian monsoon, so the cold and warm air could not converge in the Yangtze River Basin, resulting in the lack of precipitation for this region; （2） the equatorial Pacific SST showed a pattern of ＂positive in the west versus negative in the east＂, which strengthened the Walker circulation and caused local Hadley circulation anomalies at the same time, making the MLRYR controlled by abnormal sinking airflow for a long time and the conditions insufficient for producing precipitation; （3） both the events were associated with Rossby waves from the Atlantic ocean. Influenced by NAULEA teleconnection pattern, Rossby wave energy propagated eastward to the east of Eurasian and Pacific region, an East Asia trough maintained in the vicinity of 120 ~E for a long time, which strengthened the East Asian winter monsoon and further affected the precipitation of MLRYR in the winter-spring of 2011. With the mutual influence of the negative phases by telecormections of Silk Road and EAP, the Rossby wave energy accumulated in the eastern Eurasian continent and the Pacific, resulting in WPSH extending abnormally westward, which strengthened the East Asian summer monsoon and further affected the precipitation of MLRYR in summer of 2013.

关 键 词：长江中下游地区 干旱 ROSSBY波 遥相关型 

分 类 号：P426.616[天文地球—大气科学及气象学]