【摘要】 大气质量与人类的生存环境息息相关,大气中的污染物质尤其是细颗粒物质直接与间接危害人类健康,因此许多城市把对细颗粒物浓度的监测放在了重要位置。利用2017年春季关中地区的MODIS高分辨率气溶胶产品(气溶胶光学厚度,AOD)与地面PM2.5浓度监测数据进行相关性分析构建模型,结合气象观测资料建立含气象要素的多元回归模型,并将二者进行比较。结果表明,含气象要素的多元回归模型对关中地区PM2.5地面浓度的空间分布拟合度更好(r2=0.768,P<0.01)。2017年春季关中地区的PM2.5空间分布总体呈现东高西低的趋势,AOD最高值出现在西安、渭南和咸阳三市,分别为1.019、0.911和0.124。通过对一次典型污染天气进行主成分分析和基于HYSPLIT向后轨迹模型模拟其潜在传输路径发现,关中地区2017年春季大气质量受多污染物、多污染源以及多途径复合污染影响,且污染气团主要来自蒙古国西南部。研究结果对关中地区的大气污染防治与生态环境保护具有一定借鉴的意义。更多还原

【Abstract】 Atmospheric quality is closely related to human living environment. Atmospheric pollutants,especially fine particulate matter,directly and indirectly endanger human health. Therefore,many cities put the monitoring of fine particulate concentration at an important position. We analyzed the correlation between MODIS high-resolution aerosol products( aerosol optical depth,AOD) and PM2.5 concentration monitoring data in Guanzhong area in spring 2017 and constructed a direct fitting model. A multiple regression model containing meteorological elements was established by combining meteorological observation data. Those two models were compared. The results showed that the multivariate regression model with meteorological factors had better fitting degree for the spatial distribution of PM2.5 in Guanzhong area( r2= 0. 768,P < 0. 01). In the spring of 2017,the spatial distribution of PM2.5( AOD) in Guanzhong area showed a trend of being high in the east region and low in the west region. The highest value appeared in Xi’an,Weinan and Xianyang,being 1.019,0.911,and 0.124,respectively. Results from the principal component analysis of a typical polluted weather and simulation of its potential transmission path based on HYSPLIT backward trajectory model showed that atmospheric quality in Guanzhong area in spring 2017 was affected by multi-pollutants,multi-pollutant sources and multi-channel combined pollution,and the air mass mainly came from southwestern Mongolia. Our results provide reference for the prevention and control of air pollution and ecological environment protection in Guanzhong area.更多还原