A method for sampling dimethylsulfide in polluted and remote marine atmospheres

Methods have been developed for the measurement of atmospheric dimethylsulfide in both polluted and clean marine environments, avoiding Sampling losses due to reactions with atmospheric oxidants. Preconcentration of DMS on Molecular Sieve 5A was followed by analysis using gas chromatography with flame photometric detection. Prolonged contact of polluted air samples with a potassium iodide-based solution resulted in total oxidant destruction. Dimethylsulfide was measured over the Atlantic Ocean during a cruise between the U.K. and the Antarctic, between October 1992 and January 1993. In equatorial regions (30° N-30° S) the atmospheric DMS concentration ranged from 5 to 90 ng m −3 with an average of 30 ng m −3 In the polar waters and regions south of the Falkland Islands concentrations from 5 to 1050 ng m −3 were observed with a mean concentration of 120 ng m −3