ELUCIDATION OF THE TROPOSPHERIC REACTIONS OF BIOGENIC SULFUR SPECIES FROM A FIELD MEASUREMENT CAMPAIGN IN NW SCOTLAND

Dimethyl sulfide, produced as a result of the metabolism of marine phytoplankton, is emitted into the atmosphere from the sea/air interface. It has been speculated that the products of its oxidation in the atmosphere may be an important source of cloud condensation nuclei and contribute to the acidity of precipitation. Here we compare the relative concentrations of a number of sulfur compounds measured at a remote site in NW Scotland with those expected from our current understanding of DMS oxidation chemistry. Diurnal cycles in DMS and methane sulfonic acid concentrations in air were observed, consistent with the removal of DMS during the daytime by hydroxyl to form the acid, sulfur dioxide and sulfate being two other major oxidation products.