中文摘要：

以高浓度臭氧为主要特征的光化学污染是城市地区主要的大气污染问题之一。利用WRF-CALGRID空气质量模式系统模拟南京地区的光化学污染特征,结果显示前体物的浓度分布与污染物排放的情况较吻合,臭氧的高值区主要分布在城市的下风方向、源区浓度较低,白天臭氧的浓度普遍大于日平均浓度。利用WRF-CALGRID模拟减少35%前体物排放后臭氧浓度的变化,结果显示前体物浓度减小幅度与35%相差不大,减少NOx时臭氧增加、减少VOC时臭氧减少,说明南京城市区域多为VOC控制区;进一步通过光化产物指示因子分析,结果显示南京地区的指示因子数值小于敏感性过渡值,控制臭氧浓度要控制VOC的排放。利用WRF-CALGRID模拟未来气温增加条件下臭氧的变化,结果显示南京大部分地区浓度将增高1×10-9以上。城市光化学污染问题不容忽视。

英文摘要：

Photochemical pollution is one of the major air quality problems in urban areas. With the aid of air quality model system WRF-CALGRID, the concentrations of ozone and its major precursors were modeled. The modeling results match the observations well. The distribution of precursors is in good accordance with actual emission condition. The concentration of ozone in the downwind area of Nanjing is higher than that in the source areas. And the concentration in the daytime is higher than that during the day. The emissions of NOxand VOCs were reduced by 35% to further study O3-NOx-VOC sensitivity.Ozone increased when NOxwere reduced, and decreased when VOCs were reduced. Values of indicators were smaller than the sensitivity transition value. It can be concluded that Nanjing belongs to the VOC-sensitive region. Evolution trend of O3 in warmer climate was estimated. The concentration of O3 will increase over 1 ×10^-9in most parts of Nanjing. Photochemical pollution cannot be ignored in metropolis.