Airborne Studies of Stratus Clouds, Hazes and Dimethylsulfide in the Alaskan Arctic

该项目是对北极对流层气溶胶雾霾的航空现场调查，其中将包括研究海洋中二甲基硫化物(DMS)的排放以及层云的辐射和微物理特性。该项目将使用华盛顿大学拥有的一架仪表化C-131飞机。北极夏季雾霾现象被认为在北极的各种大气过程中是重要的。它通过改变云顶层的反照率和热红外通量直接影响辐射收支，并通过云凝结核(CCN‘s)对云辐射特性的调制作用间接影响辐射收支。特别是，如果能够证明DMS的排放控制了当地的CCN浓度，那么就有可能确定对北极海层反照率的生物控制。该项目将直接测量北极雾霾的分布，以及它们的化学、微物理和光学性质。将测量北冰洋DMS的浓度和通量，并估计它们对当地和全球硫收支的贡献。观测将提供用于验证卫星云参数的数据集。

This project is an airborne field investigation of aerosol hazes in the arctic troposphere, which will include studies of the emission of dimethylsulfide (DMS) from the ocean and of the radiative and microphysical properties of stratus clouds. The project will make use of an instrumented C-131 aircraft owned by the University of Washington. The arctic summer haze phenomenon is considered to be important in a variety of arctic atmospheric processes. It affects the radiation budget directly by modifying the albedo and the thermal infra-red flux at cloud top levels, and indirectly through the modulating effects on cloud radiative properties by cloud condensation nuclei (CCN's). In particular, if it can be shown that DMS emissions control the local CCN concentrations, it may be possible to identify a biological control of the arctic marine stratus albedo. The project will make direct measurements of the distribution of arctic haze, and their chemical, microphysical, and optical properties. The concentration and fluxes of DMS from the Arctic Ocean will be measured, and their contribution to the local and global sulfur budgets will be estimated. The observations will provide data sets that will be used for the validation of satellite-derived cloud parameters.