大厂县污染物浓度与气象要素相关性研究

Study on the Correlation Between Pollutant Concentration and Meteorological Factors in Dachang County

利用2014～2016年大厂县环境监测点(卫生局)日均污染物质量浓度资料和同期的常规气象观测资料,分析该县空气质量、污染物质量浓度月分布、污染物浓度与气象要素之间的相关关系以及连续重污染过程的前中后期风的分布特征。结果表明:①三年来该县空气质量有明显改善。②重污染天气首要污染物以PM2.5为主,占比87.8%。③PM2.5、PM10、SO_2月平均浓度高峰值均出现在1月至3月和10月至12月;NO_2平均浓度维持在70ug/m^3以下,在7月或8月达到最低值;O3高峰值均出现在夏季(6～8月);CO高峰值均出现在冬季(12～2月)。④典型相关分析效果优于简单相关分析;气象因素中的气温和地表温度主要影响气态污染物(O_3、CO、NO_2)的浓度;相对湿度和风速主要影响颗粒物(PM10、PM2.5)浓度以及AQI指数;降水量主要影响NO_2、SO_2的浓度。⑤地面风力≤2级是重污染天气形成之前重要的气象条件之一,同时还需要重点关注静风以及WSW～WNW之间的地面风向。

Based on the daily average pollutant mass concentration data of Dachang County Environmental Monitoring Station (Health Bureau) from 2014 to 2016 and the routine meteorological observation data at the same time, the air quality, monthly distribution of pollutant mass concentration, the correlation between pollutant concentration and meteorological factors, and the distribution characteristics of wind in the early, middle and late stages of continuous heavy pollution process in Dachang County were analyzed. The results show that:(1) The air quality in this county has improved significantly in the past three years.(2) PM2.5 is the main pollutant in heavily polluted weather, accounting for 87.8%.(3) The peak values of PM2.5, PM10 and SO in February all appeared from January to March and October to December;the average concentration of NO2 maintained below 70ug/m3 and reached the lowest value in July or August;the peak values of O3 appeared in summer (June-August);the peak values of CO appeared in winter (December-February).(4) Canonical correlation analysis is better than simple correlation analysis. Temperature and surface temperature in meteorological factors mainly affect the concentration of gaseous pollutants (O3, CO, NO2);relative humidity and wind speed mainly affect the concentration of particulate matter (PM10, PM2.5) and AQI index;precipitation mainly affects the concentration of NO2 and SO2._Ground wind force < 2 is one of the important meteorological conditions before the formation of heavy polluted weather. At the same time, we need to focus on the quiet wind and the ground wind direction between WSW and WNW.