黄璇,李栋梁. 2020. 1979-2018年5-8月中国东北冷涡建立的客观识别方法及变化特征[J]. 气象学报, (0):-, doi:doi:10.11676/qxxb2020.077
1979-2018年5-8月中国东北冷涡建立的客观识别方法及变化特征
Objective identification method and variation characteristics of the Northeast China cold vortex from May to August, 1979 to 2018
投稿时间:2019-11-28  修订日期:2020-10-22
DOI:doi:10.11676/qxxb2020.077
中文关键词:  东北冷涡,客观识别,生成位置
英文关键词:Northeast China cold vortex, Objective identification, Initial position
基金项目:国家重点研发项目
作者单位E-mail
黄璇 南京信息工程大学 xuanhnuist@126.com 
李栋梁 南京信息工程大学 lidl@nuist.edu.cn 
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中文摘要:
      东北冷涡(NECV)是中国东北地区重要的天气系统,采用欧洲中期天气预报中心(ECMWF)提供的ERA-Interim一日四次再分析资料,运用客观识别方法,检索出1979-2018年夏季(5-8月)的516个东北冷涡过程。为了研究冷涡生成位置的差异,以45°N为X轴,125°E为Y轴将研究区划分为四个象限。结果表明:夏季东北冷涡生成位置以第二象限(西北部)最多,第四象限(东南部)最少,冷涡以向东移动为主。夏季东北冷涡的平均生命史为3.2d,各象限生成的冷涡平均生命史有较大差异,第二象限最长,平均约为3.5d;第四象限最短,平均约为2.9d。72.1%的冷涡过程生命史少于4d。夏季各月第二象限生成的冷涡频数均远多于其他三个象限,且具有很明显的逐月递减的季节内变化特征。东北冷涡的生成位置和频数具有明显的年代际变化特征,5月在1998-2007年偏北,2008-2018年偏南;6月在1980-1998年南移,2008-2018年北移,1993-2003年以偏东为主,2004-2018年以偏西为主;7月在1998-2010年北移,1985-2000年偏西,2005-2012年偏东;8月在2002-2010年偏北,2009-2018年偏东。就频数而言,特别是第二象限生成的冷涡,其年代际变化在季节内存在明显不一致, 5月份,1979-1985年冷涡偏多,1986-1992年冷涡偏少;6月份,1979-1992年偏多,1993-2018年偏少;7月份,1980-1991年偏多,1992-2000年偏少。
英文摘要:
      Northeast China cold vortex (NECV) is an important weather system in northeast China. Based on the ERA-Interim four times daily reanalysis data provided by ECMWF,516 Northeast China cold vortex processes in summer (may to August) from 1979 to 2018 are searched out by objective identification method in this study. In order to study the difference of the NECV initial position, the active region of the NECV is divided into four quadrants with 45°N as the X-axis and 125°E as the Y-axis. Results show that in summer, the frequency of NECV formation is the highest in the second quadrant (northwest) and the lowest in the fourth quadrant (southeast). The NECVs are mainly moving to the east. The average persistence time of the NECV in summer is 3.2d, and is quite different when generated in different quadrant. The longest in the second quadrant (3.5d on average) while the shortest in the fourth quadrant (2.9d on average). 72.1% of the NECV process has a life history of less than 4d. The frequency of NECV process generated in the second quadrant in each month of summer is much more than that in the other three quadrants, and has an obvious characteristic of intraseasonal variation that decreases month by month. The initial position and the frequency of the NECV both have obvious interdecadal variation characteristics. In May, The NECV initial position is to the north from 1998 to 2007 and to the south from 2008 to 2018. In June, it moves southward from 1980 to 1998, northward from 2008 to 2018, to the east from 1993 to 2003 and to the west from 2004 to 2018. In July, it moves northward from 1998 to 2010, to the west from 1985 to 2000 and to the east from 2005-2012. In August, it is to the north from 2002 to 2010 and to the east from 2009 to 2018. In terms of frequency, especially in the second quadrant, the interdecadal variation of the NECV is obviously inconsistent within the season. There are more NECVs from 1979 to 1985 and fewer from 1986 to 1992 in May; more from 1979 to 1992 and fewer from 1993 to 2018 in June; more from 1980 to 1991 and fewer from 1992 to 2000 in July.
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