ABSTRACT
A time series of observations from merchant ships between the UK and the Caribbean is used to establish the variability of sea surface pCO2 and air-to-sea flux from the mid-
1990s to early 2000s. We show that the sink for atmospheric CO2 exhibits important inter-annual variability, which is in phase across large regions from year to year.
Additionally, there has been an inter-decadal decline, evident throughout the study region but especially significant in the northeast of the area covered, with the sink reducing
>50% from the mid-nineties to the period 2002-2005. A review of available observations suggests a large region of decrease covering much of the North Atlantic but excluding the
western subtropical areas. We estimate that the uptake of the region between 20o and 65oN declined by ~0.24 Pg C yr-1 from 1994/1995 to 2002-2005. Declining rates of
winter-time mixing and ventilation between surface and subsurface waters due to increasing stratification, linked to variation in the North Atlantic Oscillation, are
suggested as the main cause of the change. These are exacerbated by a contribution from the changing buffer capacity of the ocean water, as the carbon content of surface waters
increases.

http://www.uea.ac.uk/~ajw/pubs1.htm

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“A variable and decreasing sink for atmospheric CO2 in the North Atlantic ”

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http://lgmacweb.env.uea.ac.uk/ ajw/ Reprints/ Schuster_Watson_JGR_in_press.pdf