The influence of air-sea exchange on the isotropic composition of oceanic carbon: Observations and modeling
- Columbia Univ., New York, NY (United States); and others
Although the carbon isotropic composition of ocean waters after they leave the surface ocean is determined by biological cycling, air-sea exchange affects the carbon isotopic composition of surface waters in two ways. The equilibrium fractionation between oceanic and atmospheric carbon increases with decreasing temperature. In Southern Ocean Surface Waters this isotopic equilibrium enriches {delta}{sup 13}C relative to the {delta}{sup 13}C expected from uptake and release of carbon by biological processes alone. Similarly, surface waters in the subtropical gyres are depleted in {delta}{sup 13}C due to extensive air-sea exchange at warm temperatures. Countering the tendency toward isotopic equilibration with the atmosphere (a relatively slow process), are the effects of the equilibration of CO{sub 2} itself (a much faster process). In regions where there is a net transfer of isotopically light CO{sub 2} from the ocean to the atmosphere (e.g., the equator) surface waters become enriched in {sup 13}C, whereas in regions where isotopically light CO{sub 2} is entering the ocean (e.g., the North Atlantic) surface waters become depleted in {sup 13}C. A compilation of high quality oceanic {delta}{sup 13}C measurements along with experiments performed using a zonally averaged three-basin dynamic ocean model are used to explore these processes. 40 refs., 14 figs., 1 tab.
- DOE Contract Number:
- FG02-91ER61202
- OSTI ID:
- 244078
- Journal Information:
- Global Biogeochemical Cycles, Journal Name: Global Biogeochemical Cycles Journal Issue: 4 Vol. 9; ISSN 0886-6236; ISSN GBCYEP
- Country of Publication:
- United States
- Language:
- English
Similar Records
Steady-state and transient modeling of tracer and nutrient distributions in the global ocean. Progress report, August 1, 1993--July 31, 1994
The Influence of Air‐Sea CO 2 Disequilibrium on Carbon Sequestration by the Ocean's Biological Pump