2015—2016年云南省主要城市大气污染物浓度特征及其与气象要素的关系

Characteristics of Atmospheric Pollutants and Its Relationships with Meteorological Elements from 2015 to 2016 over the Sixteen Cities in Yunnan

利用2015年1月—2016年12月云南省16个城市大气污染物浓度监测结果与同期气象观测资料,分析了云南大气污染物分布的时空特征及其与气温、相对湿度、云量、降水、风速、日照时数等气象要素的关系。结果表明:2015—2016年云南空气质量优良率为89%～100%,楚雄、文山最高,景洪最低。云南16个城市除昭通、景洪、蒙自3个城市PM_(2.5)年均浓度超标外,其余城市无大气污染物超标。云南SO_2、NO_2、PM_(2.5)大气污染物浓度冬季最高,春秋季次之,夏季最低; PM_(10)、O_3平均浓度春季最高,冬季次之,夏季最低。CO平均浓度春秋季最高、冬季次之,夏季最低。云南CO浓度与气象要素相关关系不显著,其明显的月变化主要与污染排放源的变化有关。SO_2、PM_(10)、PM_(2.5)及NO_2浓度在不同地区对不同气象要素敏感性不一致,地区差异性较大。O_3日均浓度及O_3最大8 h平均浓度在云南大部地区均与平均相对湿度呈较强的显著负相关关系,与日照时数呈显著正相关关系。

Based on the daily mean mass concentrations of SO2,PM10,NO2,PM2.5,O3,CO and meteorological observed data in sixteen cities of Yunnan from January 2015 to December 2016,the annual and seasonal variation characteristics of air quality in each city and the correlations between the mass concentrations of SO2,PM10,NO2,PM2.5,O3,CO and temperature,humidity,cloud cove,precipitation,wind speed,and sunshine hours were explored.The results showed that the excellent rate of air quality in Yunnan was 89%~100%in 2015-2016,the highest in Chuxiong and Wenshan,and the lowest in Jinghong.The average annual concentration of PM2.5 exceeded the standard in Zhaotong,Jinghong and Mengzi.The other cities have no air pollution exceeding the standard in Yunnan.The seasonal concentrations of SO2,NO2 and PM2.5 were the highest in winter,followed by spring and autumn,the lowest in summer.The seasonal concentrations of PM10 and O3 were the highest in spring,followed by winter and the lowest in summer.The seasonal concentration of CO was the highest in spring and autumn,followed by winter and the lowest in summer.The correlation coefficient between the CO concentration and the meteorological elements was not significant,and the obvious monthly changes were mainly related to the changes of the pollution sources.The correlation between the concentrations of SO2,PM10,PM2.5 and NO2 and different meteorological factors in different regions was not consistent,and the regional differences were large.The daily average concentration of O3 and the maximum 8 hours average concentration of O3 were negatively correlated with the average relative humidity,and positively correlated with sunshine hours.