Based on acid rain and related contemporaneous meteorological sounding and air pollution data observed in Changchun during 2012-2015,the annual and seasonal characteristics of acid rain and their responses to meteoro-logical conditions and pollutant concentrations were investigated. The results show that Changchun city has experi-enced a transformation from weak to moderate acid rain area during the studied period. The precipitation pH indi-cates a fluctuant downward trend and is smaller in autumn and winter than that in spring and summer,while K val-ue shows an opposite trend. More specifically,the acid rain is more likely to occur in precipitation for the small magnitude in Changchun city. In addition,the severe acid rain is closely associated with south or west wind and the pH value in precipitation decreases with the increasing temperature difference and thickness of thermal inversion. Besides,a negative correlation between the pH value of rainfall and the SO2 and NO2 concentrations of the previous day is very significant,which suggests the pollution of acid rain in Changchun city is to a large extent attributed to SO2 and NO2 concentrations.%利用2012-2015年长春市酸雨观测资料和同期气象要素观测资料、探空资料及大气污染物监测资料,对长春市酸雨的变化特征及气象条件对酸雨的影响进行了分析,并研究了大气污染物浓度对酸雨的作用.结果表明:2012-2015年长春市由轻度酸雨区逐渐发展为中度酸雨区,降水pH值呈波动下降的趋势,秋季和冬季降水的pH值低于春季和夏季,降水的电导率K值呈相反的变化态势.长春市区酸雨更易发生在小量级降水中,受偏南风或偏西风影响时,酸雨污染严重;降水pH值随逆温温差和逆温厚度的增大而减小.长春市降水pH值与前一日的SO2和NO2浓度呈显著的负相关关系,可见NO2和SO2浓度对长春市酸雨污染的贡献更大.
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