One of the greatest sources of uncertainty in future climate projections is our limited understanding of how the relationship between CO 2 emissions and atmospheric CO2 concentrations will evolve. To constrain this we need to understand the behaviour of the major terrestrial and marine CO2 sources and sinks. The North Atlantic is an intense and highly variable sink region. Here we demonstrate a multi-model consensus that subpolargyre Atlantic CO2 uptake may peak in the near future before slowly declining. We link this change to a theoretical understanding of N. Atlantic CO2 behaviour and attempt to constrain the controls on the magnitude and timing of the CO2 uptake turnover.