The Oceans and Climate

The ocean is an integral part of the climate system. It contains almost 96% of the water in the Earth s biosphere and is the dominant source of water vapour for the atmosphere. It covers 71% of the planet s surface and has a heat capacity more than four times that of the atmosphere. With more than 97% of solar radiation being absorbed that falls on the surface from incident angles less than 50 from the vertical, it is the main store of energy within the climate system. 

Thus the atmospheric component of the planet s radiation budget is strongly modulated by the indirect effects of oceanic gas and particle exchange. As will be 

Issues in Environmental Seienee and Teehnology No. 13 Chemistry in the Marine Environment The Royal Soeiety of Chemistry, 2000 

While this chapter is mainly concerned with the chemical interactions between ocean and atmosphere, a few words need to be said about the physical interactions, because of their general importance for climate. The main physical interaction between the ocean and atmosphere occurs through the exchange of heat, water and momentum, although the presence of sea-ice acts to reduce all of these exchanges to a greater or lesser extent. 

Momentum is mostly transferred from the atmosphere to the ocean, having the effect of driving the ocean circulation through the production of a wind-driven flow. Of course, the resultant flow carries heat and water, so contributing to fluxes of these quantities to the atmosphere in ways that would not have occurred without the establishment of the wind-driven circulation in the first place. 

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The effect of wind velocity on (a) thin-film thickness and (b) piston velocity. The solid line represents results obtained from measurements made in wind tunnels. In situ measurements were made from distributions of the naturally occurring radioisotopes of carbon and radon. Source From (a) Broecker, W. S., and T.-H. Peng (1982). Tracers in the Sea. Lamont-Doherty Geological Observatory, p. 128, and (b) Bigg, G. R. (1996). The Oceans and Climate. Cambridge University Press, p. 85. 

G.R. Bigg, The Oceans and Climate, Cambridge University Press, Cambridge, 1996, ch. 3, p. 85. 

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