Centennial AMOC variability in a perturbed parameter ensemble of the EMIC iLOVECLIM

The Atlantic Meridional Overturning Circulation (AMOC) is an important set of large-scale ocean currents that impacts regional climates on a wide variety of timescales due to its transport of heat to high northern latitudes. Understanding internal AMOC variability on (multi)centennial timescales is important for accurate attribution of recent changes in AMOC strength to internal variability or to anthropogenic forcing, and to improve future climate projections.  However, much remains unknown about the spatiotemporal structure and underlying physical mechanisms of (multi)centennial AMOC variability (CAV). Recent research with various Earth System Models (ESMs) and Earth System Models of intermediate complexity (EMICs) have shown several different potential mechanisms of CAV across models, with the dominant mechanisms taking place in different regions, such as the Arctic, subtropical North Atlantic, or Southern Ocean. Here, we take a different approach and analyse how mechanisms of CAV vary within a perturbed parameter ensemble of the EMIC iLOVECLIM. Specifically, we investigate whether parameter choice alters spatio-temporal aspects of a model specific mechanism of CAV, or whether parameter choice alters the dominance of different mechanisms of CAV within the model. The ensemble is analysed using the spatiotemporal pattern recognition technique Multi-channel Singular Spectrum Analysis (MSSA).