Atmospheric Sulfur Dioxide Over the Southern Ocean: Shipboard and Land-based Measurements During the ACE-1 Experiment

小行星9420157 这个项目是南半球海洋浮质特性试验的一部分，该试验将于1995年在遥远的南太平洋进行，利用飞机、船上和地面测量各种化学物质、物理和气象参数，其中心目标是调查大气浮质的形成、演变和光学特性。在这一部分中，大气二氧化硫将在研究船“发现者”号上和塔斯马尼亚的格里姆角进行测量。使用的仪器是高效液相色谱荧光装置，能够检测10 ppt二氧化硫，测量时间少于10分钟。除二氧化硫外，还将在船上对空气中的硫化氢进行基于滤光片的荧光衰减测量。硫化氢是二氧化硫的前体，目前没有这一海洋区域的数据。 该项目的目标是建立塔斯马尼亚以南南大洋海洋边界层中二氧化硫的预算。具体而言，将估计以下数量：1）二甲基硫醚氧化产生的二氧化硫，2）气相硫酸的光化学损失率，以及3）云、海盐气溶胶和海面损失的相对重要性。将使用海洋边界层的光化学箱模型和详细的非均相化学模型对现场数据进行解释。最终，这项工作将有助于发展的机制模型的生产和海洋空气中的硫酸气溶胶的增长。为了发展对全球变化和地球辐射收支中气溶胶/云成分之间相互关系的预测能力，显然需要这种模式。

9420157 Saltzman This project is part of the Southern Hemisphere Marine Aerosol Characterization Experiment (ACE-1), which will be conducted in the remote Southern Pacific in 1995 using aircraft, ship-board, and ground-based measurements of a wide variety of chemical species, physical and meteorological parameters with the central goal of investigating the formation, evolution, and optical properties of atmospheric aerosol. In this component, atmospheric sulfur dioxide will be measured aboard the research vessel Discoverer and at Cape Grim, Tasmania. The instruments to be used are HPLC-fluorescent devices which are capable of detecting 10 ppt sulfur dioxide with a measurement period of less than 10 minutes. In addition to sulfur dioxide, filter-based fluorescence decay measurements of hydrogen sulfide in air will be made on board the ship. Hydrogen sulfide is a precursor to sulfur dioxide and no data are currently available from this region of the oceans. The goal of this project is to construct a budget for sulfur dioxide in the marine boundary layer over the Southern Ocean, south of Tasmania. Specifically, the following quantities will be estimated: 1) the yield of sulfur dioxide from the oxidation of dimethyl sulfide, 2) the photochemical loss rate to gas phase sulfuric acid, and 3) the relative importance of losses to clouds, sea-salt aerosols and to the sea surface. The interpretation of the field data will be done using a photochemical box model of the marine boundary layer coupled to a detailed model of heterogeneous chemistry. Ultimately, this work will contribute to the development of mechanistic models for the production and growth of sulfuric acid aerosols in marine air. Such models are clearly needed in order to develop a predictive capability for the interrelation between global change and the aerosol/cloud component of the earth s radiative budget.