Detecting Saturation in the Ocean Carbon Sink
A.R. Jacobson
Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309; 303-497-4916, E-mail: andy.jacobson@noaa.gov
Recently, the 4.5 million observations used to create the Takahashi et al. (2009) surface ocean pCO2 climatology were released to the scientific community. This collection of individual pCO2 observations has never before been available to researchers outside the ocean carbon community, and this opportunity has generated innovative new lines of research. In this presentation, I demonstrate a new method for the fusion of pCO2 data, which manifest all the intense variability of the upper ocean, with ocean interior carbon data, which through ocean inverse methods provide a strong constraint on long-term mean surface fluxes of CO2. With some climatological flux information coming from interior observations, the obligation of surface observations to constrain long-term means by themselves is reduced. The surface observations can more fully express their interannual and mesoscale variability in this framework, and I model that variability in terms of satellite observables such as sea surface temperature. I use this technique to evaluate multi-decadal trends in global surface ocean pCO2, in order to test recent claims that the ocean carbon sink is saturating.
Figure 1. Locations of the more than 4.5 million surface ocean pCO2 observations during 1968-2008 in the recently released Takahashi et al. (2009) database.