Global ocean emission of dimethylsulfide predicted from biogeophysical data -: art. no. 1078

Among the biosphere-atmosphere interactions that influence climate, the emission of dimethylsulfide (DMS) from the ocean plays a prominent role for its high potential in cloud albedo regulation. In order to advance in our understanding and quantification of this coupled ocean-atmosphere system, both synoptic and predictive capabilities must be largely improved. Hitherto, large-scale oceanic DMS has eluded being captured from remote sensing, correlated with synoptic variables, or simulated by mechanistic modeling. We have found a simple empirical relationship that permits global-ocean monthly distributions of DMS concentration to be computed from a combination of remotely sensed biospheric data (chlorophyll a) and climatological geophysical data (mixed layer depth). This relationship allows for the desired synopticity and predictability in the ocean-to-atmosphere sulfur flux, which we have globally quantified as 23-35 Tg S yr(-1). Also, our algorithm stands in support of a biogenic-DMS/solar-radiation negative feedback and opens the door toward quantifying its strength and its response to global warming.