Reduced sulphur species and their transformations

Oceans contribute about 20% of biogenic sulphur into atmosphere (15-20 Tg/yr). Various biological processes drive the sulphur cycle in the surface of the open ocean. Through these biological processes various sulphur compounds are produced in the ocean and the volatile sulphur compounds are emitted to the atmosphere among them dimethylsulphide (DMS) is the most abundant biological sulphur compound. Andreae (1990) estimated the flux of the DMS to be 0.6-1.6 Tmol S/year. The emission of DMS into the atmosphere is taking place due to its very large concentration difference across the air-water interface.