Boucher O. auteur aut IRD Moulin C. auteur aut IRD Belviso S. auteur aut IRD Aumont Olivier auteur aut IRD Bopp L. auteur aut IRD Cosme E. auteur aut IRD Von Kuhlmann R. auteur aut IRD Lawrence M.G. auteur aut IRD Pham M. auteur aut IRD Reddy M.S. auteur aut IRD Sciare J. auteur aut IRD Venkataraman C. auteur aut IRD text journalArticle eng The global sulphur cycle has been simulated using a general circulation model with a focus on the source and oxidation of atmospheric dimethylsulphide (DMS). The sensitivity of atmospheric DMS to the oceanic DMS climatology, the parameterisation of the sea-air transfer and to the oxidant fields have been studied. The importance of additional oxidation pathways (by O₃ in the gas- and aqueous-phases and by BrO in the gas phase) not incorporated in global models has also been evaluated. While the global DMS flux is well constrained at 24-27 Tg S yr ^-1, there are large differences in the spatial and seasonal distribution of the atmospheric DMS flux generated from the three climatologies of oceanic DMS considered here. The relative contributions of OH and NO₃ radicals to DMS oxidation depends critically on which oxidant fields are prescribed in the model. Oxidation by O₃ appears to be significant at high latitudes in both hemispheres. Oxidation by BrO could be significant even for BrO concentrations at sub-pptv levels in the marine boundary layer. specialized 021 032 2 4 1181-1216 2002 https://www.documentation.ird.fr/hor/PAR00002856 https://www.documentation.ird.fr/hor/PAR00002856 Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2009-03-24 2017-08-23 PAR00002856 fre