5～8月东北冷涡客观识别分类及北半球大气环流特征分析  

The Objective Recognition and Classification of Northeast Cold Vortex and the Northern Hemisphere Atmospheric Circulation Characters in May to August

作　　者：刘刚[1,2] 廉毅 颜鹏程 曾宇星[1] 杨旭[2,3] 曹玲[4] 

机构地区：[1]兰州大学大气科学学院,甘肃兰州730000 [2]吉林省气象科学研究所,中高纬度环流系统与东亚季风研究开放实验室,吉林长春130062 [3]解放军理工大学气象海洋学院,江苏南京211101 [4]吉林省气象服务中心,吉林长春130062

出　　处：《地理科学》2015年第8期1042-1050,共9页Scientia Geographica Sinica

基　　金：国家自然科学基金上项目(41405094;41175083;41375078;41275096);吉林省科技发展计划项目(20150204023SF)资助

摘　　要：采用美国国家环境预报中心(NCEP)500 h Pa高度场逐日再分析资料,基于计算机客观识别方法,统计了1948~2012年5~8月东北冷涡活动过程。结果表明:共计发生东北冷涡过程956次,平均每年5~8月发生约14.7次;东北冷涡活动共4 129 d,5~8月平均分别为14 d、18 d、18 d和14 d,共64 d,占5~8月总天数的52%;5~8月东北冷涡过程以持续3~6 d为主,冷涡活动主要位于121°E^131°E,48°N^53°N区间;5~8月东北冷涡发生频次和活动天数均存在显著增长趋势。7~8月东北冷涡活动异常多年份,贝湖至鄂海阻高与东北冷涡多同时发生,异常少年份,贝湖至鄂海阻高亦不盛行,且阻高先发生冷涡后发生年份占多数。5~6月和7~8月东北冷涡典型特多年高度距平合成场与特少年的主要异常区分布呈反位相,且这种反位相特征在对流层中、高层(200 h Pa、500 h Pa)均呈近半球尺度的波列分布;5~6月和7~8月东北冷涡活动特少年和特多年差值高度场合成分布相近,均呈现显著的南北向"+、-"波列分布(置信度水平≥99%),正负波列分别位于西北太平洋区域和鄂霍次克海至白令海区域,该波列对应高度层风场中的相对位置为气旋和反气旋式环流。Based on the NCEP/NCAR daily reanalysis data of 500 hPa geopotential height, objective identifica-tion method by computer is used to search the Northeast China cold vortex（NECV） activities ongoing process in summer（May to August） from 1948 to 2012 in this study. Results show that the NECV process occurred 956 times in total, the average annual occurred about 14.7 times in May-August. And the NECV events of 4 129 days, wherein 14、18、18 and 14 days are occurred in May to August, respectively, a total of 64 days 52%of the total number of days. The NECV process main sustained 3-6 days, maintaining position between the 121°E-131°E and 48°N-53°N. Simultaneously, the NECV occurrence frequency and active days significant in-creases. In July-August, the strong NECV year,Lake Baikal to the Sea of Okhotsk blocking high regularly si-multaneoued with the NECV. On the contrary, in the weak NECV year, Lake Baikal to the Sea of Okhotsk blocking high was not prevailed,and in most year the NECV happenned after the blocking high.The Differenc-es in geopotential height anomaly distribution between the strong NECV year and the weak NECV year ap-pear anti-phase distributed, moreover this feature in the middle（500 hPa） and senior（200 hPa） convection showed a nearly hemispherical scale wave train distribution. However their composite differences in geopoten-tial height were similarity , showed a significant meridional＂＋,-＂wave train（exceed 99%confidence level）, this wave train was located in the Pacific Northwest region and the Sea of Okhotsk to the Bering Sea region, corresponding to the senior convection cyclonic and anticyclonic circulation.

关 键 词：东北冷涡 客观识别 分类 环流特征 

分 类 号：P445[天文地球—大气科学及气象学]