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Mechanisms Controlling the Air-Sea Flux of CO2 in the North Atlantic

  • Mick Follows
  • Richard G. Williams
Part of the NATO Science Series book series (NAIV, volume 40)

Abstract

The air-sea flux of carbon is controlled by the disequilibrium in partial pressure of carbon dioxide between the atmosphere and surface ocean. This disequilibrium is a consequence of the interactions of physical, chemical and biological processes in the ocean and, today, includes a response to the anthropogenic increase of atmospheric pCO 2. Fig. 1 illustrates the annual mean airsea flux of carbon, F, estimated from a knowledge of the atmospheric partial pressure, pCO 2 at and compilation of surface pCO 2 observations by Takahashi et al. (1999). The air-sea flux of carbon is determined by
$$ F = - {K_g}{K_0}(pC{O_2} - pCO_2^{at} $$
(1)
where K 0 is the solubility of CO 2 at local temperature and salinity. K g is the air-sea gas transfer coefficient, which is dependent on local environmental conditions and is usually parameterized as a function of wind speed, sea-surface temperature and sea-surface salinity (Wanninkhof, 1992). The major global scale features in Fig. 1 are the outgassing of CO 2 from the tropical oceans, and the influx at mid and high latitudes. In this chapter we focus on understanding what sets the basin wide, and regional patterns of air-sea carbon flux in the North Atlantic basin. While we focus on the North Atlantic, some of the concepts and discussions are also relevent to other regions of the ocean.

Keywords

Mixed Layer Gulf Stream Subtropical Gyre Cyclonic Eddy Subpolar Gyre 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media Dordrecht 2004

Authors and Affiliations

  • Mick Follows
    • 1
  • Richard G. Williams
    • 2
  1. 1.Program in Atmospheres, Oceans and Climate, Department of Earth Atmosphere and Planetary SciencesMassachusetts Institute of TechnologyCambridgeUSA
  2. 2.Oceanography Laboratories, Department of Earth and Ocean SciencesUniversity of LiverpoolLiverpoolEngland

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