中纬度地区大气汞消减、控制因素及其对我国大气汞传输的影响

项目名称： 中纬度地区大气汞消减、控制因素及其对我国大气汞传输的影响

项目编号： No.41273145

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 付学吾

作者单位： 中国科学院地球化学研究所

项目金额： 75万元

中文摘要： 大气不同形态汞的转化是研究全球性汞迁移、输送和分布规律的一个核心环节。传统的大气汞理论多是基于陆地近地表的大气物理化学状况，是制约全球性汞生物地球化学循环研究发展的一个瓶颈。自由对流层（富含臭氧且干燥）和海洋边界层（富含无机溴及其化合物和海盐气溶胶）是可能存在显著气态单质汞（Hg0）消减和活性气态汞（GOM）生成的重要场所。作为全球人为源排放最为集中的区域，对中纬度地区自由对流层和海洋边界层大气汞形态转化的研究，对全球汞的生物地球化学循环起至关重要的作用。通过研究长白山自由对流层入侵事件和我国东部海洋边界层不同形态大气汞的转化及其和臭氧、无机溴及其化合物的关系，分析大气汞形态转化的影响因素，并估算自由对流层和海洋边界层Hg0 的大气居留时间。此工作的开展为将来正确认识我国汞排放参与全球传输的份额及我国偏远地区和近海海洋汞的输入及生态环境效应提出重要的基础数据。

中文关键词： 大气汞；清除作用；形态转化；传输；

英文摘要： Transformation of mercury (Hg) species in the atmosphere plays a crucial role in the transportation and distribution of Hg in the global scale. However, there are many uncertainties are associated with the global biogeochemical cycle of Hg due to limitations of the current knowledge with respect to Hg fate in the atmosphere, which were mostly developed from studies in the lower troposphere. The free troposphere is generally characterized by high ozone concentrations and dry air, and the air in the marine boundary layer is enriched with inorganic bromine and sea-salt aerosols. Therefore, it is reasonable to speculate that there is a fast transformation of gaseous elemental mercury (Hg0) to reactive gaseous mercury (GOM).The mid-latitude is the most important anthropogenic Hg source region over the world, and therefore it is of importance to the study the transformation of Hg species in the free troposphere and marine boundary layer in the mid-latitude. In this proposed project, we will try to study the fate and transformation of Hg species in the free troposphere intrusion air in Mt. Changbai area and marine boundary layer in Eastern China, as well as its relationships with atmospheric ozone and inorganic bromine compounds. This will help us to elucidate the factors which influence transformation of atmospheric s

英文关键词： Atmospheric mercury；Depletion；Transformation；Transport；