Atlantic Meridional Overturning Circulation:
Low-Frequency Variability and Model Representation
The Atlantic meridional overturning circulation (AMOC) is thought to play a major role in decadal and longer time-scale climate variability as well as in prediction of the earth’s future climate on these time scales. However, because only rather short records of continuous observational estimates of AMOC transports are available at very limited locations and only for the recent period, support for such a prominent role for AMOC primarily comes from model simulations. Here, we examine representations of AMOC low-frequency (decadal to multi-decadal) variability and mechanisms from forced ocean and coupled model simulations as well as from data assimilation products and identify some robust and non-robust aspects. We also present our new 40-member ensemble of initialized decadal prediction simulations, highlighting levels of skill in predicting upper-ocean heat content and land precipitation.