青藏高原低涡客观识别与图像学分析  

Objective Identification and Image Analysis on Qinghai-Tibet Plateau Vortex

作　　者：丁禹钦 胡文东[1,2,3] 邵建 李金泽 徐文嘉 贾净翔 佟景哲 DING Yuqin;HU Wendong;SHAOJian;LI Jinze;XU Wenjia;JIA Jingxiang;TONG Jingze(College of Atmospheric Sciences,Chengdu University of Information Technology,Chengdu 610225,China;Key Laboratory of Software Automatic Generation and Intelligent Service of Sichuan Province,Chengdu 610225,China;Key Laboratory of Plateau Atmosphere and Environment,Sichuan Province,Chengdu 610225,China;Yinchuan Meteorological Bureau,Yinchuan 750002,China)

机构地区：[1]成都信息工程大学大气科学学院,四川成都610225 [2]软件自动生成与智能服务四川省重点实验室,四川成都610225 [3]高原大气与环境四川省重点实验室,四川成都610225 [4]银川市气象局,宁夏银川750002

出　　处：《成都信息工程大学学报》2021年第6期674-679,共6页Journal of Chengdu University of Information Technology

基　　金：四川省基础应用重点资助项目(2018JY0056);中国气象局-成都信息工程大学气象软件工程联合研究中心资助项目(2020102);宁夏重点研发资助项目(2018BEG03002);中国气象局资助项目(CMAYBY2019-131)。

摘　　要：为进一步分析青藏高原低涡的分布特征,对1979-2018年的高原低涡进行客观识别并引入图像学方法展开分析。结果表明:40年间,高原低涡年均生成35.1个,1997与2005年高原低涡出现频次最高,达53个,1984年出现频次最少,为21个;图像学分析显示,在高原低涡初生时,24.1%的正涡度中心位于高原低涡的南部,占比最高,东部和北部的正涡度中心分别占19.5%和16.5%;在高原低涡发展时,正涡度中心有29.9%集中于高原低涡重心附近,西南部和西部占比达到了20.3%和17.9%;东北、西南和北部占比之和仅有9.1%。引入描述热带气旋的Okubo-Weiss(OW)参数V_(OW),V_(OW)的负值项与切变有很强的相关性。研究发现,有24.5%的V_(OW)项负值区中心位于高原低涡的东部区域,21.8%位于高原低涡的西北区,16.6%位于高原低涡的重心附近。在单个高原低涡生命周期内,有51.0%的V_(OW)项负值区中心相对于高原低涡几乎不移动,15.5%的V_(OW)项负值区中心则会向东移动。In order to further analyze the distribution characteristics of the Qinghai-Tibet Plateau vortex,this article objectively identifies the plateau vortex from 1979 to 2018 and introduces imaging methods for analysis.The results show:in the past 40 years,35.1 plateau vortices were generated every year.In 1997,the plateau vortex was the highest,reaching 53,and in 1984,the frequency was the least.Image analysis shows that 24.1%of the positive vorticity centers are located in the southern part of the plateau vortex at the beginning of the plateau vortex,which accounts for the highest proportion.The positive vorticity centers in the east and north account for 19.5%and 16.5%,respectively;during plateau vortex development,29.9%of the positive vorticity center was concentrated near the center of gravity of the plateau low vortex,the proportions of the southwest and west reached 20.3%and 17.9%;the sum of the proportions of the northeast,southwest and north was only 9.1%.The Okubo-Weiss(OW)parameter(V_(OW))describing tropical cyclones is introduced.The negative value of V_(OW)has a strong correlation with shear.The study found that 24.5%of the negative V_(OW)term center is located in the eastern region of the plateau vortex,21.8%is located in the northwest region of the plateau vortex,and 16.6%is located near the center of gravity of the plateau vortex.During the life cycle of a single plateau vortex,the center of 51.0%of the negative value area of V_(OW)almost does not move relative to the center of the plateau vortex,and the center of 15.5%of the negative value of V_(OW)will move eastward.

关 键 词：气象学 天气系统分析 客观识别 图像学 V 参数 

分 类 号：P443[天文地球—大气科学及气象学]