重庆地区大气污染分布特征及气象因子相关分析

Analysis on Distribution Characteristics of Air Pollution and It’s Correlation with Meteorological Factors in Chongqing Area

大气污染状况的时空分布特征是大气污染研究的基础。利用2017年~2019年重庆地区40个站点主要污染物浓度日均值监测资料及气象观测资料,总结出各类污染物的时空分布特征并比较区域差异,分析重庆地区各类污染物与气象因子的相关关系。结果表明:(1)PM_(2.5)、PM_(10)、O_(3-8h)年平均浓度都呈现西高东低的分布特征;NO_(2)年平均浓度的高值区位于中心城区,从中心城区向东向西辐射减弱;SO_(2)在重庆全区域的污染较轻;CO浓度高值区位于重庆东北部。(2)污染物超标日数,西部地区高于东部地区。(3)PM_(2.5)和PM_(10)各月浓度中西部地区高于东部地区,O_(3-8h)中心城区的浓度值7~8月明显高于其他五个区域,NO_(2)中心城区的浓度值在每个月份都远高于其他区域。(4)重庆地区O_(3-8h)浓度变化与气象因子的相关性高于PM_(2.5)和NO_(2),说明二次污染物O_(3-8h)浓度变化相比一次污染物更易受气象条件的影响。重庆地区大气污染分布特征及气象因子相关的分析,为预测重庆地区各大区域的大气污染物浓度变化及评估扩散条件提供科学依据。

The spatial and temporal distribution characteristics of air pollution are the basis of air pollution research.Based on the daily monitoring data of main pollutant mean concentration and meteorological observation data of major pollutants at 40 stations in Chongqing from 2017 to 2019,the spatial and temporal distribution characteristics of various pollutants were summarized,the regional differences were compared,and the correlation between various pollutants and meteorological factors was analyzed.The results showed that:(1)the annual mean concentrations of PM_(2.5),PM_(10) and O_(3-8) hwere higher in the west and lower in the east;The level of annual mean concentration of NO_(2) is high in the central urban area,and radiatively become lower to the east and west;The pollution of SO_(2) in the whole area of Chongqing is relatively light.The high value area of CO concentration is located in the northeast of Chongqing.(2)The number of days in which pollutants exceed the standard were higher in the west and lower in the east.(3)The monthly concentration values of PM_(2.5) and PM_(10) in central and western regions are higher than those in eastern regions.The concentration value of O_(3-8) hin central urban area is higher than the other regions from July to August.The concentration of NO_(2) in the central urban area is much higher than that in other areas every month.(4)The correlation between O_(3-8) hconcentration change and meteorological factors in Chongqing area is higher than that of PM_(2.5) and NO_(2),indicating that the concentration change of secondary pollutants O_(3-8) his more susceptible to meteorological conditions than that of primary pollutants.The analysis of the distribution characteristics of air pollution and the correlation of meteorological factors in Chongqing provides a scientific basis for predicting the variation of atmospheric pollutant concentration and evaluating the diffusion conditions.