摘要
利用高空和地面常规观测、分钟级自动观测、葵花8号静止气象卫星及NCEP/FNL再分析等资料,对贵州省黔南地区近10年范围最广的两次辐射雾天气过程(2017年2月5日,简称“20170205”过程和2023年11月27日,简称“20231127”过程)的环流形势、水汽条件、热动力条件及爆发性增强条件等进行对比分析,探讨东南部单个站点持续时间异常短的原因。结果表明:两次过程均受均压场控制,大气层结稳定、微风及雨后初晴的夜空为大雾的形成和维持提供有利环境,爆发性增强主要由“降温”造成;荔波站点雾持续时间异常短均为雾发生初期风速突然增大造成。对流层低层的热力学、动力学结构差异导致两次雾过程的范围、强度和爆发性增强特征不同,“20170205”过程本地水汽、西南方向水汽输送、水汽辐合、逆温层厚度及强度均强于“20231127”过程,“20170205”过程弱下沉运动抑制近地面水汽向高层扩散,“20231127”过程低层上升气流使近地面有限的水汽向上输送,不利于地面浓雾的维持和发展。
Using conventional upper-air and surface observations,minute-level automatic weather station data,Himawari-8 satellite imagery,and NCEP/FNL reanalysis data,a comparative analysis was conducted on the circulation patterns,moisture conditions,thermodynamic and dynamic conditions,and explosive intensification mechanisms of the two most extensive radiation fog events(occurring on February 5,2017,and November 27,2023)in southern Guizhou over the past decade.The causes of for the abnormally short duration at a single station in the southeast were also explored.The results are as follows:Both fog events occurred under a uniform pressure field.Stable atmospheric stratification,light winds,and clear skies following rain provided favorable conditions for fog formation and maintenance.The explosive intensification of both fog processes was primarily triggered by rapid surface cooling.The abnormally short fog duration at Libo Station during both events was due to a sudden increase in wind speed at the initial stage of fog formation.Significant differences in the thermodynamic and dynamic structures of the lower troposphere led to variations in the spatial extent,intensity,and explosive intensification characteristics between the two fog events.Moisture conditions,southwesterly moisture transport,and moisture convergence in the‘20231127’process were notably weaker than those in the‘20170205’process.Weak subsidence in the‘20170205’process suppressed the upward diffusion of near-surface moisture,whereas low-level ascent in the‘20231127’process transported the limited near-surface moisture to higher levels,which was less conducive to the maintenance and development of dense fog at the surface.
作者
苟杨
廖波
彭科曼
黄麟媛
宋彦棠
Gou Yang;Liao Bo;Peng Keman;Huang Linyuan;Song Yantang(Meteorological Qiannan Buyei and Miao Autonomous Prefecture of Guizhou Province,Duyun 558000,China;Guizhou Meteorological Service Center,Guiyang 550002,China;Guiyang Meteorological Bureau,Guiyang 550002,China)
出处
《沙漠与绿洲气象》
2026年第1期147-155,共9页
Desert and Oasis Meteorology
基金
贵州省科技计划项目(黔科合支撑[2022]YB286)。
关键词
大范围辐射雾
诊断分析
爆发性发展
亮温差法
large-scale radiation fog
diagnostic analysis
explosive intensification
brightness temperature difference method
