2016-2020年珠三角地区PM_(2.5)时空变化特征分析

Analysis of the Characteristics of the Temporal and Spatial Changes of PM_(2.5) in the Pearl River Delta from 2016 to 2020

基于2016—2020年珠三角地区环境空气PM_(2.5)监测历史数据,研究珠三角地区九个城市PM_(2.5)的时空变化特征,以期为珠三角地区的PM_(2.5)空气污染预防与治理提供相关数据支持。结果表明:珠三角9个城市的PM_(2.5)年均值可以看出珠三角地区的细颗粒物PM_(2.5)浓度近三年逐年降低,特别是2020年PM_(2.5)年均值均在25μg·m^(-3)以下。2019年PM_(2.5)浓度优良率为100%的城市三个,2020年PM_(2.5)浓度优良率为100%的城市五个。九个城市同一年PM_(2.5)月均值曲线变化趋势基本一致,2016—2020年珠三角地区6、7月PM_(2.5)月均值都较低,冬季PM_(2.5)月均值相对都较高。冬季气温低,降雨量少,大气层稳定,不利于颗粒物扩散。6月、7月珠三角地区受西南方向的南海季风气候影响,PM_(2.5)月均值都较低。

Based on the historical data of ambient air PM_(2.5) monitoring in the Pearl River Delta region from 2016 to 2020,study the temporal and spatial characteristics of PM_(2.5) changes in nine cities in the Pearl River Delta region,with a view to providing relevant data support for PM_(2.5) air pollution prevention and governance in the Pearl River Delta region.The results show that the annual average PM_(2.5) value of 9 cities in the Pearl River Delta shows that the PM_(2.5) concentration of fine particulate matter in the Pearl River Delta region has decreased year by year in the past three years,especially the annual average PM_(2.5) value in 2020 will be below 25μg·m^(-3).In 2019,there are three cities with a 100%excellent and good PM_(2.5) concentration,and five cities with a 100%excellent PM_(2.5) concentration in 2020.The trend of the monthly mean value of PM_(2.5) in the nine cities in the same year is basically the same.From 2016 to 2020,the monthly mean value of PM_(2.5) in June and July in the Pearl River Delta region is relatively low,and the monthly mean value of PM_(2.5) in winter is relatively high.In winter,the temperature is low,the rainfall is small,and the atmosphere is stable,which is not conducive to the diffusion of particulate matter.In June and July,the Pearl River Delta region was affected by the South China Sea monsoon climate in the southwest,and the monthly average value of PM_(2.5) was low.