Dimethyl sulfide and its oxidation products in the atmosphere of the Atlantic and Southern Oceans

Dimethyl sulfide, methane sulfonate, non-sea-salt sulfate and sulfur dioxide concentrations in air were obtained during a cruise between the U.K. and the Antarctic during the period October 1992-January 1993. In equatorial regions (30 degrees N to 30 degrees S) the atmospheric DMS concentration ranged from 3 to 46 ng (S)m(-3) with an average of 18 ng(S)m(-3). In the polar waters and regions south of the Falkland Islands concentrations from 3 to 714 ng(S)m(-3) were observed with a mean concentration of 73 ng(S)m(-3) Methane sulfonate concentrations were also enhanced in the vicinity of the Antarctic Peninsula and in the Weddell Sea. A simple model of DMS oxidation was used to estimate the ocean to atmosphere flux rate,and this was found to be within the range of previous estimates, with a mean value of 1011 ng(S) m(-2) h(-1).