- Conference Proceedings Paper
A key factor in determining the predictability of the climate system, and by extension of climate change, is the sensitivity of the meridional overturning circulation (MOC), commonly referred to as thermohaline circulation, to forcing and changes in forcing from the atmosphere. This problem is addressed by analyzing the geographic patterns of sensitivity of the steady-state MOC to atmospheric wind stresses and the fluxes of heat and water at the ocean-atmosphere interface. These sensitivity maps are obtained from the adjoint version of the MIT Ocean General Circulation Model. The patterns of sensitivity are substantially different when the ocean model is forced by fixed surface boundary conditions and when the ocean model is coupled to a simple energy balance model. This highlights the importance of atmospheric transport of heat and water in determining climate sensitivity and predictability. Striking points which will be discussed include the role of gateways to the Atlantic basin such as the Drake passage and the area of the Agulhas retroflection, and the role of convection in conveying information about perturbations in the model.