The team is charged with assessing the physical mechanisms underlying AMOC variability and the potential predictability of the AMOC. Both natural and anthropogenically-induced variations are being pursued. 

View TT3 Near- and Long-Term Priorities

Near-term priorities

• Investigate how surface exchanges of buoyancy and momentum between the ocean and the atmosphere/cryosphere drive the AMOC circulation across a broad range of timescales from monthly to millennial (i.e., quasi-steady-state).
• Clarify the apparent disagreement between models of different complexity regarding i) the role of Southern Ocean wind and ii) the role of Nordic Seas overflows in maintaining and modulating the AMOC.
• Quantify the magnitude, location, and physical mechanisms associated with interior diapycnal mixing in the ocean, which contribute to the diabatic AMOC, and evaluate the realism of current GCMs in this regard.
• Investigate the role of freshwater forcing and South Atlantic freshwater transports in determining the variability and stability of the AMOC.
• Expand the use of eddy-resolving models, particularly in regional/process studies designed to: i) test the robustness of AMOC variability mechanisms identified in coarser GCMs or idealized models; ii) address the origins of persistent model bias in the North Atlantic region (e.g., Gulf Stream separation and the North Atlantic Current path); and iii) assess the role of ocean turbulence in AMOC variability.
• Quantify the predictability properties of AMOC in idealized and comprehensive models and identify mechanisms that affect these properties.
• Explore the mechanisms associated with AMOC variability on centennial-to-millennial timescales, and evaluate the realism of GCMs on these timescales relative to available paleo proxy data, perhaps using proxy-enabled coupled climate models.

Long-term priorities

• Translate the knowledge developed about AMOC variability and predictability mechanisms into reliable decadal climate forecasts.
• Incorporate mesoscale eddy-resolving ocean models more fully into the toolkit used for AMOC mechanisms/prediction studies, including long coupled GCM simulations, in order to address questions about the role of turbulence in controlling AMOC.
• Synthesize results from theoretical, idealized models, and more complex GCM investigations into a common conceptual framework regarding key AMOC variability mechanisms and identify the resulting predictability of the AMOC.

The task team will also coordinate with the U.S. CLIVAR Decadal Predictability Working Group as well as the CLIVAR Working Group on Ocean Model Development and CLIVAR Global Synthesis and Observational Panel.