欧亚持续性阻塞对6月大兴安岭地区气温和降水的影响及气温的前兆信号研究  

Effect of persistent blocking in Eurasian on temperature and precipitation in June in Greater Khingan Mountains and the precursor signal of temperature

作　　者：张博 于超 黄威 陈传雷 ZHANG Bo;YU Chao;HUANG Wei;CHEN Chuan-lei(National Meteorological Center,Beijing 100081,China;Liaoning Meteorological Disaster Monitoring Early Warning Center,Shenyang 110166,China)

机构地区：[1]国家气象中心,北京100081 [2]辽宁省气象灾害监测预警中心,辽宁沈阳110166

出　　处：《气象与环境学报》2021年第4期63-69,共7页Journal of Meteorology and Environment

基　　金：国家自然科学基金青年基金项目(41905091);中国气象局预报员专项(CMAYBY2019-138)共同资助。

摘　　要：根据国际新开发的可识别持续闭合性阻塞和开放性高压脊事件的判别方法,讨论了欧亚地区不同区域500 hPa持续性高值事件(PMZ)的发生频率及其对中国大兴安岭地区夏季气温和降水的影响。结果表明:欧亚105°—125°E区域内PMZ事件与夏季尤其是6月大兴安岭地区气温关系最为紧密。105°—125°E地区PMZ事件频发时,贝加尔湖至中国东北地区异常高压引起的下沉增温及晴空辐射造成大兴安岭地区气温偏高,同时,该地区对流层低层相对湿度条件较差,配合对流层中低层异常反气旋性环流系统以及下沉运动,不利于大兴安岭地区出现明显降水。此外,5月中亚两河流域位势高度可作为6月大兴安岭地区气温的前期预报指标,当中亚两河流域5月位势高度场偏高(低)时,6月贝加尔湖以东地区位势高度偏高(低),对应大兴安岭地区同期气温偏高(低)。Based on a newly developed international discrimination method for identifying continuous closed blocking and open high ridge events,the frequency of 500 hPa persistent high-value events(PMZs)in different regions of Eurasia and its influence on summer temperature and precipitation in the Greater Khingan Mountains were discussed.The results show that the PMZ events in the region of Eurasia from 105°-125°E are closely related to the summer temperature in the Greater Khingan Mountains,especially in June.When PMZ events occur frequently in the 105°-125°E region,the subsidence warming caused by the abnormally high pressure from Lake Baikal to Northeast China and the clear sky radiation results in the high air temperature in the Greater Khingan Mountains region.Meanwhile,the relative humidity in the lower troposphere of this region is poor,combined with the abnormal anticyclonic circulation system in the middle and lower troposphere and the subsidence movement.It is not conducive to significant precipitation in the Greater Khingan Mountains region.In addition,the geopotential height in the Mesopotential Basin of Central Asia in May can be used as a pre-forecast index of the temperature in the Greater Khingan Mountains in June.When the geopotential height field in the Mesopotential Basin of Central Asia in May is high(low),the geopotential height in the east of Lake Baikal in June is high(low),corresponding to the temperature in the Greater Khingan Mountains in the same period is high(low).

关 键 词：闭合性阻塞 发生频次 开放性高压脊 气温预报指标 

分 类 号：P468[天文地球—大气科学及气象学]