Climate change induced by human activity will impact the oceans in unprecedented ways. Interactions among ocean basins are also expected to change, and much effort will be required to better understand and predict these changes. This chapter starts by an overview about projected changes in processes participating in ocean interactions and mentioned in previous chapters. The overview starts with the intensity and frequency of the Pacific and Atlantic Niños. This is followed by a review of decadal climate modes in the Pacific and other basins, as well as past climate shifts in the Pacific. The following two sections discuss the ocean’s thermohaline circulation, its projected changes, and its potential collapse. The last section addresses present-day and future global mean sea level rise and its geographical variations due to ocean warming and land ice loss (from glaciers, Greenland, and Antarctica).

This chapter presents a conceptual discussion on how ocean–atmosphere interactions are key to outstanding aspects of climate variability. The principal goal is to describe the mechanisms by which the atmosphere and ocean interact, and their perturbation feedback on each other, as well as how these interactions can lead to a new breed of modes in the coupled ocean–atmosphere system. The realization of such local interactions can project onto basin scales, and subsequently to the other basins.