What did we do? We analyzed the transport of fossil fuel CO2 in an ocean model using density as the coordinate.
What did we find? Tracking the flow of carbon within the ocean, we found that almost 2/3 of the fossil fuel CO2 enters via gas exchange in waters less dense than the base of the ventilated thermocline. However, almost 2/3 of it is stored below the ventilated thermocline.
Why is it important? Ocean is the dominant sink of fossil fuel CO2 on the timescales of century and longer. Our study highlights the crucial role of ocean circulation between the subtropical and subpolar regions that sets the pathway of carbon sequestration into the deep sea.
Reference: Iudicone D., K. B. Rodgers, Y. Plancherel, O. Aumont, T. Ito, R. Key, G. Madec and M. Ishii, (2016), The formation of the ocean’s anthropogenic carbon reservoir, Scientific Reports, doi:10.1038/srep35473