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

9420157萨尔茨曼这个项目是南半球海洋气溶胶特性实验的一部分，该实验将于1995年在遥远的南太平洋进行，使用飞机、船载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气溶胶的形成、演变和光学性质。在这个组成部分中，大气中的二氧化硫将在发现者号科考船和塔斯马尼亚州格里姆角进行测量。将使用的仪器是高效液相色谱-荧光设备，能够检测10ppt的二氧化硫，测量时间少于10分钟。除了二氧化硫，还将在船上进行空气中硫化氢的滤光片荧光衰减测量。硫化氢是二氧化硫的前体，目前还没有来自这一海洋区域的数据。该项目的目标是为塔斯马尼亚南部南大洋的海洋边界层中的二氧化硫建立一个预算。具体来说，将估计以下数量：1)二甲基硫化物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。对实地数据的解释将使用海洋边界层的光化学盒子模型和非均相化学的详细模型。最终，这项工作将有助于开发海洋空气中硫酸气溶胶的产生和生长的机械模型。显然，为了发展预测全球变化与地球S辐射预算的气溶胶/云部分之间的相互关系的能力，这种模式是必要的。

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.