中国东部地区灰霾对大气辐射和边界层气象影响的模拟研究

Integrated methods of observation analysis, model development and simulation will be applied to explore and to reveal the spatial and temporal distributions of aerosol chemical components during haze event over east China,and the relative contributions of anthropogenic and natual aerosols, primary and secondary aerosols to PM2.5 (particulate matter of diameter less than 2.5 microns), the effects of hygroscopic growth and mixing state on aerosol optical properties,the direct radiative forcing due to haze aerosols,the differences in aerosol optical property and radiative forcing between haze and non-haze periods, the impacts of haze aerosols on atmospheric radiation,surface energy balance, boundary layer meteorology and its feedback on surface layer atmospheric chemistry and air pollutants distribution.The findings of this study will be valuable for understanding the haze radiative and climatic effects.

通过观测资料分析、模式发展和模拟研究，揭示中国东部地区灰霾中气溶胶化学成分的时空分布特征，确定人为和自然源气溶胶、一次和二次气溶胶对PM2.5质量浓度的相对贡献；了解气溶胶吸湿增长、混合状态对于气溶胶光学特性的影响机制；给出灰霾气溶胶产生的直接辐射强迫及其空间分布；比较并认识灰霾和非灰霾期气溶胶光学特性和辐射强迫的差异；揭示灰霾对大气辐射、地表能量平衡、边界层气象要素的影响及其对近地层大气化学反应和污染物浓度分布的反馈机制。该研究结果将有助于认识灰霾的辐射和气候效应。

本项目通过观测资料分析、模式发展和模拟研究，了解了气溶胶吸湿增长对气溶胶光学性质和大气辐射的影响；得到了中国东部气溶胶浓度和光学参数的垂直分布特征，硝酸盐气溶胶浓度和直接辐射强迫的空间分布和季节变化特征；认识了华北地区霾污染期间PM2.5及其成分、能见度和气溶胶光学厚度的分布特征和变化规律；定量估算了华北地区近地面PM2.5的不同来源贡献；揭示了气溶胶对大气辐射、地表能量平衡、边界层气象要素的影响以及对近地面污染物的反馈作用。