The role of North Atlantic ocean dynamics in the uptake of heat and carbon

A key source of uncertainty in predictions of transient climate change is the uptake of heat and carbon by the ocean. The ocean is often described as diffusive with the mixing timescale setting the long-term adjustment of the climate system. The goal of this study is to demonstrate the role of the ocean dynamics in determining the uptake of heat and carbon under different climate change scenarios and therefore in setting the key timescales scale associated with anthropogenic climate change. Using a hierarchy of models, from idealised to state-of-the-art climate models, and various idealised and realistic emission scenario pathways, we describe the role of the large scale dynamical processes in determining the timescales associated with global warming: key results include the importance of the dynamical adjustment timescales associated with the meridional overturning circulation and the circulation in the southern ocean and most importantly showing that mixing is not as important as previously thought. The dynamics and response of the large scale overturning circulation circulation due to surface forcing will be discussed as well highlighting some key discrepancies in coupled climate models and their representation of the MOC.