Investigating the role of Sea-Surface Salinity (SSS) in simulating historical AMOC decadal variation

A new study, supported by CPO’s Climate Variability and Predictability Program (CVP) demonstrates that realistic Atlantic meridional overturning circulation (AMOC) decadal variations can be simulated in a coupled climate model by sea-surface temperature (SST) and sea-surface salinity (SSS) restoring. As a heat transport current in the North Atlantic, AMOC is an important component in Earth’s climate, and having realistic simulations of it is key to decadal climate predictions. Forced ocean – sea ice (FOSI) model simulations are used to initialize decadal climate predictions in a fully coupled model. However, due to systematic differences in the atmospheric state used for FOSI and that of the coupled climate model, achieving a balanced atmosphere-ocean state continues to be a struggle. As a result, prediction skill may be lower than expected.