Dimethylsulphide: Oceans, Atmosphere and Climate

Dimethylsulphide (DMS), emitted by marine phytoplankton, is the second most important source of atmospheric sulphur, after anthropogenic SO2. In the atmosphere, DMS is transformed into condensable acidic sulphur products and, through gas-to-particle conversion, it becomes the most important natural source of atmospheric sulphate aerosols. Possible climatic effects have been suggested, linked to the negative radiative forcing due to scattering of solar radiation and especially to modification of cloud albedo over oceans by sulphate aerosol particles. These effects occur in addition to those deriving from the superimposed anthropogenic component of the atmospheric sulphate. Understanding the cycle of DMS in the marine troposphere and its interaction with the aerosol budget and cloud properties has become a key research target over the past few years. Our knowledge of the many processes involved is still fragmentary, however. This book, which updates the state of our comprehension of the marine DMS cycle with special regard to its climatic impact, should be of interest to marine biologists, atmospheric chemists, aerosol physicists and climatologists, and to scientists concerned with changes in the Earth's climate.