THE DIMETHYL SULFIDE REACTION WITH ATOMIC CHLORINE AND ITS IMPLICATIONS FOR THE BUDGET OF METHYL-CHLORIDE

DMS is produced in large quantities by natural oceanic processes. Its chemistry and emissions have been postulated to play a role in the rad iative balance of the atmosphere. While its reactions with OH and NO3 radicals are well known, the reaction with chlorine atoms in the marin e boundary layer has also been suggested recently. If this produces CH 3Cl, it would contribute to the global budget of this naturally occuri ng halocarbon. Experiments were carried out to measure the yield of CH 3Cl in the C1+DMS reaction. CH3Cl was indeed formed in this reaction i n laboratory experiments at 1 atm. and 298 K, with a small yield of (1 .34 +/- 0.07) x 10(-3). This yield is sufficiently small that the cont ribution to the global CH3Cl budget is estimated to be less than or eq ual to 2% and it is unlikely to be responsible for the anomalously hig h CH3Cl concentrations measured recently over the Labrador Sea.