Title: Role of the Southern Ocean in changes of past atmospheric CO₂ and implications for the future

Authors: Laurie Menviel

Affiliations: Climate Change Research Centre, University of New South Wales, Australia.

Abstract: The Southern Ocean (SO) has been identified as a crucial region modulating the concentration of atmospheric CO₂. The sustained upwelling of carbon-rich deep waters and inefficient nutrient utilization at the surface of the SO leads to an outgassing of CO₂. Changes to the SO circulation, resulting from both dynamic and buoyancy forcing, can alter the rate of upwelling, as well as formation and subsequent transport of Antarctic bottom and intermediate waters. This impacts the air-sea CO₂ exchange in the SO and the carbon content of these water masses. In this talk, I will discuss the processes that might have led to changes in SO circulation over the last glacial period and deglaciation, as well as the impact of these changes on the marine carbon cycle and atmospheric CO₂. I will further discuss how recent and projected climate change might impact SO circulation and the capacity of the SO to uptake CO₂.

Biography: Laurie Menviel is a Scientia associate Professor at the Climate Change Research Centre, the University of New South Wales, Sydney, and a chief investigator of the Australian Centre for Excellence in Antarctic Science. Her research focuses on understanding the role of oceanic circulation in past and future abrupt climate change, including changes to the global carbon cycle and atmospheric CO₂ concentration.  She explores these themes by performing numerical experiments with Earth system models and comparing with proxy records or observations. She is a co-editor in chief of Climate of the Past.
She obtained a PhD in oceanography from the University of Hawaii, USA, held post-doctoral positions at the University of Hawaii, University of Bern and the University of New South Wales, and obtained two Australian Research Council fellowships.