From local to global scale - marine emissions of the climate relevant sulfur gases carbonyl sulfide, carbon disulfide and dimethyl sulfide

Oceanic emissions of sulfur containing trace gases alter global atmospheric chemistry. The gases act for example as aerosol precursors and change the radiative budget of the Earth, with a significant impact on climate. Large uncertainties exist in the amount of sulfur gases emitted from the ocean, and a gap in the atmospheric budget of carbonyl sulfide – the most abundant sulfur gas in the atmosphere – has been suggested to result from tropical ocean emissions. This thesis uses new shipbased measurements from the tropical Pacific and Indian Ocean together with models to quantify these emissions. Three studies were performed: 1) A 3D model study to test how oceanic emissions can be represented in atmospheric chemistry climate models, 2) A combination of new shipbased data and box model calculation to derive a global emission estimate of carbonyl sulfide and 3) a detailed process study of production processes and their drivers for the gases carbonyl sulfide and carbon disulfide in the Eastern tropical South Pacific. Together, the results yield a new temporally and spatially resolved emission climatology of the three gases