Western boundary currents as conduits for the ejection of anthropogenic carbon from the thermocline
A long-standing question regarding the ocean carbon cycle is whether western boundary currents (WBCs) and their extension regions provide an important pathway for anthropogenic carbon (Cant) uptake, thereby contributing to the known importance of these regions in the climate system. Successive versions of the Lamont Doherty Earth Observatory air-sea carbon dioxide (CO2) flux climatologies (Takahashi et al. 2002, 2009) indicate that, at the very least, there is a broad correspondence between the maxima in CO2 fluxes (uptake) and surface heat fluxes (release of heat to the atmosphere over the western subtropical gyres and WBCs). Motivated to understand the mechanistic controls on the ocean carbon cycle in these regions, a number of modeling and observationally based studies have drawn on multiple platforms to constrain fluxes both at the surface and in the interior of this region (Fassbender et al. 2017, and references therein; Nakano et al. 2011).