Processes governing the coupling of the atmosphere and ocean occur on a range of time and space scales and modulate weather and climate variability, as well as the ocean uptake of excess heat and carbon. This project is focused on advancing understanding of atmosphere-ocean coupling on mesoscales (100-1000 km) over the Southern Ocean and its impact on the long-term, large-scale climate variability of the region. This addresses a significant gap in the current understanding of mesoscale atmosphere-ocean coupling regarding its role in decadal to multi-decadal climate variability. The Southern Ocean has some of the most continuous and significant mesoscale ocean variability on the planet, motivating the choice to focus on this region. The investigators hypothesize that mesoscale air–sea interaction related sea surface temperature anomalies lead to large-scale reorganization of the mid-latitude jet stream over the Southern Ocean, which in turn feeds back onto the large-scale currents and mesoscale ocean variability in the region. To explore this idea, the investigators will use a hierarchy of coupled climate models of different resolutions and complexities, allowing them to isolate and explore regional-scale processes, as well as examine these processes in conjunction with larger-scale influences. The project’s focus on advancing understanding of climate variability on decadal time scales has strong societal implications. The project also includes the mentoring of undergraduate a