J. Phys. IV France 139 (2006) 197-209
Biogeochemical processes in the ocean and at the ocean-atmosphere interfaceA. Saliot
LOCEAN, IPSL$/$UPMC$/$CNRS$/$MNHN$/$IRD, Université Pierre et Marie Curie, Case 100, 75252 Paris Cedex 05, France
(Published online: 9 January 2007)
The ocean can be considered as a chemical reactor, whose energy sources are the various matter inputs originating from the continent and the ocean. Among various elements, carbon plays a key role as it is involved in both inorganic form as CO2 and organic forms such as compounds synthesized through photosynthesis. Thus, the ocean is presently an active actor in climate change and ocean-atmosphere exchange processes. This review will present some insights into: 1) schematic representations of the carbon cycle, with emphasis on CO2 exchange between the ocean and the atmosphere and to the organic parts of this cycle, 2) concepts relative to the biological pump of CO2, with a detailed view on photosynthesis, 3) concepts leading to the existence of oceanic provinces and associated productivity for open sea and coastal areas, 4) addressing the question: what is the net efficiency of the biological pump of CO2 in terms of exportation of organic carbon and sequestration in sediments and 5) specific aspects on biogeochemical processes occurring at the boundary between the ocean and the atmosphere.
© EDP Sciences 2006