中国地区臭氧前体物对地面臭氧的影响

利用GEOS-Chem模式的数值试验结果,研究中国地区NOx和两类VOCs对O3质量浓度分布及其化学机理的影响。研究表明,NOx的减少会使得中国西部O3质量浓度显著降低,但在冬季NOx的减少会使得东北、华北地区O3质量浓度上升。而京津唐地区由于VOCs/NOx比值偏低,不能通过单一减少NOx来控制O3质量浓度。VOCs排放的减少会使得我国东部地区O3质量浓度大幅减少,其中人为VOCs的减少能降低我国东部地面O3质量浓度,而生物VOCs的减少只能在夏秋季有效减少我国东部地区35°N以南区域的地面O3质量浓度。控制地面O3质量浓度时,中国西部主要考虑NOx的减排,东部35°N以北主要考虑AVOCs的减排,而30~35°N应同时考虑AVOCs和BVOCs的减排,在30°N以南的地区,则需要全面考虑NOx和VOCs的减排。

Impacts of O3 Precursor on Surface O3 Concentration over China

The impacts of nitrogen oxides（NOx）,anthropogenic and biogenic volatile organic compounds（AVOCs and BVOCs） on distribution and mass concentration of O3 over China are examined by using the global chemical transport model GEOS-Chem.Model results indicate that,with a 50% reduction of NOx emissions,mass concentration of O3 is predicted to decrease remarkably in western China,but to increase in Northeast and North China in winter because of the low ratio of VOCs to NOx there,especially in Beijing-Tianjin-Tangshan area.Mass concentration of O3 decreases in eastern China with a 50% reduction of AVOCs emissions in the whole year,and does in eastern China south of 35°N with a 50% reduction of BVOCs only in summer and autumn.Thus,NOx emissions in western China,AVOCs emissions in eastern China north of 35°N,both AVOCs and BVOCs emissions between 30°N and 35°N in eastern area,whereas both NOx and VOCs emissions in eastern area south of 30°N should be considered for O3 control.