广州市PM2.5污染时空分布规律及重污染时段下气象因素的影响

Spatial and Temporal Distribution of PM2.5 in Guangzhou and the Impact of Meteorological Factors during High Pollution Episodes

利用2017年广州市49个环境空气自动监测站的监测数据,结合5个地面气象站气象资料,对广州PM2.5的时空分布情况、与PM10的关系以及重污染时段下气象因素对PM2.5质量浓度的影响进行分析,结果显示:广州市全年PM2.5浓度分布整体呈现南、北较低,中部偏高的态势;4月至10月为PM2.5污染水平较低的月份;四个季度PM2.5均值差异较大,主要受气候影响;在重污染时段下,PM2.5质量浓度与气压、风速成明显负相关,温度较低的夜间,易发生逆温现象,导致污染物积累。

Byusing the monitoring data of 49 ambient air quality monitoring stations and meteorological data from 5 surface meteorological stations in Guangzhou in 2017, this study carried out the analyses of spatial and temporal distribution of PM2.5,relationship between PM2.5 and PM10 and influence of meteorological factors on the mass concentration of PM2.5 under high pollution time period. The results indicate that the PM2.5 concentration was lower in south and north part of Guangzhou yet remains high in the central. The change of PM2.5 concentration was mainly driven by weather effects and shows seasonal patterns in all stations, with a relatively lower bound from April to October. During high pollution episodes, negative correlation was found between PM2.5 concentration and air pressure and wind speed. At night when the temperature is low, temperature inversion occurs easily, leading to the accumulation of pollutants.