基于气流轨迹聚类分析方法浅析桂林市酸雨来源

Study on the Source of Acid Rain in Guilin Based on the Clustering Method of Backward Trajectory

通过对桂林市2009—2013年的酸雨状况及变化趋势分析,结果表明:桂林市酸雨强度及频率从2010年出现峰值后,呈现逐渐下降的趋势;酸雨的季节分布差异明显,冬、春季酸雨频率较高,夏季相对较低;酸雨中的阴离子主要为SO2-4和NO-3,阳离子主要为Ca2+和NH+4。利用后向轨迹和聚类分析方法对桂林市酸雨来源进行气流轨迹模拟分析,结果显示,主要作用气流来自南方地区,其中东南和偏东南方向气流形成的降雨酸性较强,酸雨频率较高。

The acid rain situation and trends were analyzed in Guilin during 2009 to 201 3.The result showed that a declining trend appears after the peak intensity and frequency of acid rains in 201 0 in Guilin.It was significantly different of seasonal distribution in acid rain,the larger the frequency of acid rain was present to winter and spring,it was lower at summer.The cations in acid rain mainly were SO2 -4 and NO -3 ,the anions mainly were Ca2 + and NH +4 .The precipitation source and influence of acid rain by air masses in Guilin were a-nalysis.The result showed that the southern region was the main source of air masses.Among them,the acidity of precipitation and the frequency of acid rain were higher that formed by air masses from southeast.