“丝绸之路”模态与东亚夏季环流的关系  

The Relationship between the Silk Road Mode and the Summer Atmospheric Circulation over East Asia

作　　者：李艳[1] 张英华 郑凤魁 袁有林 LI Yan;ZHANG Yinghua;ZHENG Fengkui;YUAN Youlin(College of Atmospheric Sciences,Lanzhou University,Lanzhou 730000,China;The Meteorologica Observatory of Unit 94582 of the Chinese People＇s Liberation Army,Queshan 463217,China;The Meteorological Observatory of Unit 93123 of the Chinese People＇ s Liberation Army,Liaoyang 111000,China;The Meteorological Observatory of Unit 63610 of the Chinese People＇s Liberation Army,Korla 841001,China)

机构地区：[1]兰州大学大气科学学院 [2]94582部队气象台 [3]93123部队气象台 [4]63610部队气象台

出　　处：《沙漠与绿洲气象》2018年第3期10-17,共8页Desert and Oasis Meteorology

基　　金：国家自然科学基金(41775051)资助

摘　　要：基于1979—2015年ERA-Interim再分析资料,分析了夏季"丝绸之路"(the Silk Road,即SR)模态与东亚地区大气环流之间的联系,结果表明:在SR模态正异常年,200 hPa亚洲急流在东亚地区比较弯曲,在中国新疆和环渤海地区500 hPa上分别有一个高度脊和一个高度槽,在蒙古国、中国内蒙古以及日本以东500 hPa上有显著的位势高度正异常,风场异常与高度场配合较好。在对流层中低层的中国北方,有明显的下沉气流,在中国内蒙古、蒙古国以及日本以东,出现位涡负异常,而在朝鲜半岛附近,则有位涡正异常出现。中国环渤海地区降水偏少,而日本大部分地区降水偏多。在SR模态负异常年,200 hPa急流相对平直且更强,500 hPa的波列特征比正异常年更加显著,在中国内蒙古和蒙古国、朝鲜半岛、日本以东分别有"-、+、-"分布的位势高度场异常。与正异常年相比,位于东亚135°E附近的正异常中心变得显著,在该异常中心的西侧和东侧分别有上升和下沉异常气流,对应在朝鲜半岛和中国东北附近有较大的位涡负异常。在环渤海、朝鲜半岛南部和日本、日本以东洋面上,降水分别出现偏多、偏少和偏多现象。Based on the ERA-Interim reanalysis data from 1979 to 2015,the impact of the Silk Road mode（SR）on summer atmospheric circulation over East Asia was analyzed. Results indicated that in positive years of the SR mode,the 200-h Pa Asian jet was winding over East Asia,there was a geopotential ridge over Xinjiang of China,and a trough over Bohai region,respectively. There were significantly positive 500-hPa geo-potential height anomalies over Mongolia,Inner Mongolia of China,and to the east of Japan,and wind field cooperated well with the height field. Downward flows appeared in middle and lower troposphere over northern China,and negative anomalies of potential vorticity（PV） appeared over Mongolia,Inner Mongolia of China and to the east of Japan,and positive anomalies of PV appeared over the Korean peninsula. The precipitation was less than normal over Bohai region,and was more than normal over most areas of Japan. In the negative years of the SR mode,the 200-hPa Asian jet was flatter and stronger than in positive years. The 500-hPa wave trains were more significant than in positive years. It showed a feature of ＂-,＋,-＂distribution of geopotential height anomalies over Mongolia and Inner Mongolia,the Korean peninsula,and to the east of Japan,respectively. The positive circulation center near 135° E over east Asia was more significant than in positive years. Upward flows appeared on its west and downward flows appeared on its east,respectively. There were strong negative anomalies of PV over Korean peninsula and northeast China correspondingly. Precipitation was more than normal over the Bohai region and to the east of Japan,respectively,and it was less than normal over the south of Korean peninsula and Japan.

关 键 词：“丝绸之路”模态 东亚大气环流 亚洲急流 降水 位涡 

分 类 号：P426.6[天文地球—大气科学及气象学] P434.4