Sensitivity Analysis Of The Atmospheric Ozone And Fine Particulate Matter Concentrations To Meteorological Conditions In China

In recent years,with the rapid development of economy and the acceleration of urbanization,China experiences serve regional haze events all through the year,which seriously damage the human health,influence the air quality and lead to climate change.The photochemical pollution events with high-concentration ozone and the continuous frog haze weather with fine particulate matter have always been the social concerns.Meteorological conditions play an important role in the formation of O₃ and PM_2.5 pollution.The aim of this study is to analyze the influence of various meteorological parameters on the ozone and fine particulate matter concentrations in China using an air quality model.Then we explore the meteorological factors that play a leading role in the process of diffusion,transmission and transformation of air pollutants.The results can offer references in the process of environmental management and support the design makers.In this paper,the perturbation parameters is changed in variety,such as temperature,wind,humidity,mixing height,cloud liquid water and precipitation.The O₃,PM_2.5 concentrations and its components in the period of January and July 2013 were simulated by Models-3/CMAQ.The comparison of the simulated results are as follows:?1?In the case of relatively stable emission sources in a region,meteorological conditions have greatly influence on the O₃ and PM_2.5 concentrations,but the effects of different meteorological factors on the concentration of pollutants are obviously different.?2?The temperature has the greatest influence on the concentration of O₃.Except Guangzhou and Xi'an,the average daily maximum 8h O₃ concentration has obviously positive correlation with temperature,the humidity has a smaller but significant effect.The increase of relative humidity is beneficial to the accumulation of atmospheric free radicals and the precursors,thereby affecting the concentration of the O₃.The change of wind speed,mixing height and cloud liquid water has minimal impact.But as temperature rise,the O₃ concentration decreases in southwest and parts regions of northeast China in July in the spatial distribution.?3?Temperature has a major effect on average PM_2.5 due largely to the evaporation of ammonium nitrate and organic aerosol at higher temperatures.There is a negative correlation between wind speed and fine particulate matter concentration,mainly because of wet deposition and promoting diffusion of fine particulate matter.The change of mixing height and humidity also has a significant effect on the average PM_2.5 concentration.In a certain relative humidity range,high humidity conditions are likely to cause serious pollution of atmospheric particulates.Cloud liquid water and precipitation have the smallest influence on average PM_2.5 concentration.The sensitivities of O₃ and PM_2.5 concentrations to changes in these meteorological parameters indicate that changes in climate could potentially have important impacts on O₃ and PM_2.5 concentrations.