气候变化对浙江省大气污染的影响

开展气候变化对大气污染影响的研究有利于加深对大气污染形成机理的认识.利用1996-2015年浙江省大气成分、气象观测资料，分析气候变化对大气污染的影响.结果表明，近20 a来浙江省呈年高压天气日数增多、年均气温升高、降水集中及年均净辐射、日照时数、风速、气温日较差和水汽蒸发量都下降的气候变化事实.气候变化引起大气污染扩散能力下降，1996-2015年杭州市和浙江省年均大气扩散指数分别下降了0.55和0.81，降幅分别达35.71%和42.69%.大气扩散指数与ρ（PM₁₀）、ρ（PM_2.5）及年霾日数之间呈显著负相关，当大气扩散指数增大时，大气颗粒物浓度和年霾日数均下降，反之亦然.杭州市大气扩散指数与ρ（PM₁₀）、ρ（PM_2.5）之间的相关系数分别为0.73和0.76.杭州市和浙江省大气扩散指数与年霾日数之间的相关系数分别达到0.77和0.78，T检验值则分别为28.88和30.81，说明由气候变化引起的大气扩散能力改变是影响大气污染的重要原因，但不同大气成分受气候变化的影响程度不同.影响ρ（PM₁₀）的关键气候要素是降水量、风速及相对湿度等，影响ρ（PM_2.5）的主要是辐射、气温，影响ρ（SO₂）的主要是气温，影响ρ（NO₂）及ρ（NO₃-）、ρ（NH₄+）的主要是辐射.总体来说，浙江省近20 a的气候变化事实可能有利于促进ρ（PM₁₀）、ρ（PM_2.5）、ρ（NO₂）及ρ（O₃）等上升，促进ρ（SO₂）、ρ（NO₃-）、ρ（SO₄2-）、ρ（NH₄+）等下降. 

The Influence of Climatic Change on Air Pollution in Zhejiang Province

The research on the influence of climate change on air pollution is helpful to deepen understanding of the formation mechanism of air pollution. Based on comprehensive observations of complex atmospheric pollutions and meteorology from 1996 to 2015, the influence of climatic change on air pollution was investigated in Zhejiang Province. The results showed the obvious climatic changes of more frequent high-pressure weather, the increase of temperature as well as precipitation concentration, and even the decrease of net radiation, sunshine duration, wind speed, daily temperature range and evaporation capacity were found. The climatic change caused the decline of the capacity of atmospheric diffusion. The annual average atmospheric diffusion coefficients descend to 0.55 and 0.81 that the descent percentages are nearly 35.71% and 42.69% in Hangzhou City and Zhejiang Province, respectively. The atmospheric diffusion index presents the strong inverse correlation with the concentrations of PM₁₀, PM_2.5 and annual haze day, and the concentrations of PM₁₀, PM_2.5 as well as annual haze day presents decreasing trend with the atmospheric diffusion index increasing and vice verse. The correlation coefficients between the atmospheric diffusion index and concentrations of PM₁₀, PM_2.5 are 0.73 and 0.76 in Hangzhou City, respectively. The correlation coefficients between the atmospheric diffusion index and annual haze day are 0.77 and 0.78 in Hangzhou City and Zhejiang Province, respectively, and T-values in test are 28.88 and 30.81. The result illustrates the capacity of atmospheric diffusion induced by climatic change is an important influence factor of atmospheric pollution, but the different pollutants are differently affected by climatic change. The key climatic elements are precipitation, wind speed and relative humidity influenced on PM₁₀ concentration, and then atmospheric radiation, air temperature as well as precipitation on PM_2.5 concentration. The most important climatic element on SO₂ and SO₄^2- concentration is air temperature. Different from sulfide, the most significant climatic element on NO₂, NO₃^- and NH₄⁺ concentration is atmospheric radiation. On the whole, climatic change in Zhejiang Province in recent 20 years may be benefit to the concentration increases of PM₁₀, PM_2.5, NO₂ and O₃ as well as the concentration decreases of SO₂, NO₃^-, SO₄^2- and NH₄⁺.