大连地区酸雨外来源分析

Analysis of external source of acid rain in Dalian

应用Hysplit传输扩散模式计算2008—2009年大连地区酸雨和非酸雨期间的后向气流轨迹,利用条件概率和轨迹聚类法分析气流轨迹,探讨大连地区酸雨外来源。结果表明:外来源通过大气输送对大连地区酸沉降的贡献较大。大连地区酸雨主要受中国华东沿海至山东半岛经黄海中北部或经渤海及其西岸的近地面大气污染输送影响,中国华东和华南等南方内陆地区和日本海周边东亚国家对大连地区酸雨均有贡献。海洋性气团或北方大陆气团一般为大连地区非酸雨来源。

Air parcel backward trajectory during periods with acid and no-acid rain from 2008 to 2009 in Dalian was calculated based on a Hysplit model,and external source of acid rain was analyzed by methods of a conditional probability distribution and a trajectory clustering.The result shows that the external source transported through at-mosphere makes a greater contribution to acid deposition in Dalian area.The main source of acid rain owe to near-surface atmospheric transportation comes from the East China coast to Shandong peninsula,passing through north Huanghai Sea or Bohai Sea and its west coast,and the lower-air atmospheric transportation from the inland area of southward and eastward of China and East Asia countries around Japan Sea provides additional sources.On the contrary,source of no-acid rain comes from ocean air mass or northward land air mass.