广西一次大范围长时间臭氧污染过程分析

基于广西区域的地面气象观测数据、臭氧浓度数据和臭氧激光雷达观测资料,采用后向轨迹方法,分析了2021年6月6-8日广西出现的一次大范围长时间由南向北变化的臭氧污染过程的形成原因.结果 表明,此次臭氧区域污染的主要原因是本地臭氧生成,次要原因是珠三角地区臭氧向广西区域输送;臭氧浓度与气象要素密切相关,与气温呈现较为一致的正相关,与降水量、地面风速和相对湿度呈现较为明显的负相关.     

STUDY ON THE VISIBILITY REDUCTION CAUSED BY ATMOSPHERIC HAZE IN GUANGZHOU AREA

In recent years the pollution of aerosol is getting worse and worse in Guangzhou area. The haze weather mainly occurs from October to April of the following year, resulting in visibility deterioration. From the beginning of the 1980's the visibility dramatically deteriorated, obviously increasing haze weather, in which there are three big fluctuations, respectively showing the periods of pollution of dust, sulphate and dust, fine particle from photochemical process and sulphate and dust accompanying the development of economy. The long-term tendency of visibility caused by fog and light fog does not have the tendency due to human activity or economical development and the variation mainly show the inner interannual and interdecadal variation of climate. The deterioration of visibility has close relation to the fine particles in Guangzhou area, with half of PM10 surpassing the limits set by national second graded standard, meanwhile, all values of PM2.5 rise above the day-mean limits of American national standard, indicating very high fine particle concentration. The ratio of PM2.5 to PM10 is also very high, reaching 62% - 69%, especially higher in dry seasons than in rainy seasons.     

广西区域霾过程高低空大气环流型影响分析

利用1980—2015年NCEP/NCAR逐日再分析资料和广西80个地面气象站资料,采用Lamb-Jenkinson方法对广西区域霾过程的大气环流进行分型,并探讨高低空环流型配置与区域霾过程的关系。结果表明:当地面东南风型、高空西风型时,广西出现霾过程的频率最高;地面东风型配合高空西风型对年霾过程的贡献最大,地面东南风型配合高空西风型主要出现在冷暖气流转换的春季、地面低压型配合高空高压脊型出现在西太平洋副热带高压明显加强、地面处于弱低压环境场的夏季、地面东风型配合高空西风型出现在环流稳定平直的秋季、地面东风型配合高空高压脊型出现在环流经向度明显增强的冬季,霾过程具有冬季多发、夏季少发的特点。近36年来,地面东风型配合高空高压脊型是广西霾过程呈偏多趋势的主导环流型。