How the ocean ventilates heat and carbon

A primary challenge to 21st century global climate predictability is understanding the ocean’s role as a heat and carbon sink or source to the atmosphere. The Southern Ocean surrounding Antarctica absorbs vast quantities of heat and carbon in its surface waters that subduct to the ocean interior where they are stored at centennial timescales. Rates of global climate change occurring at decadal to centennial scales ultimately depend on the ocean processes occurring in the Southern Ocean. However, there is large uncertainty to the magnitude and variability of these oceanic heat and carbon pathways and how they will change in a warming world. Much of this uncertainty stems from our poor knowledge of the key ocean dynamics that determine the physical environment of the polar oceans. The focus of this project is on the ocean’s fine-scale circulation near its surface. As an oceanographer, I investigate these circulations at the scale of 1-100 km in size and how they vertically ventilate the ocean. It is through these currents that the key climate currencies of heat and carbon are transported from the ocean surface towards the deep ocean interior of several kilometers depth, and therefore away from the atmosphere.