Project description
Unravelling the secrets of ocean circulation
The Weddell Sea, located in the northernmost part of mainland Antarctica, plays a crucial role in the circulation of the world’s oceans. Even subtle changes can have significant impacts on floating ice shelves, which in turn affect global sea levels, the production of deep water and the overall circulation of the world’s oceans. The ERC-funded WAPITI project will investigate the regional pathways of water masses in the Weddell Sea using both experimental and numerical oceanography techniques. It will focus on the factors that shape the three-dimensional structure and pathways of water masses in the Weddell Sea, as well as the factors that influence the flow of deep waters between the Antarctic ice shelves and the global ocean circulation.
Objective
Deep water formed around the Antarctic continent drives the world ocean circulation. 50-70% of this deep water is formed within only about 10% of the Antarctic circumpolar band: the Weddell Sea. Subtle changes in the circulation of the Weddell Sea can lead to major changes in floating ice-shelves, with critical implications for global sea-level, the production of deep water and the global ocean overturning circulation. Despite these critical climate implications, the Antarctic shelf circulation remains poorly understood.
I propose an ambitious project at the crossroads of experimental and numerical oceanography. By drawing on the strengths of each discipline I will explore the regional water-mass pathways in the Weddell Sea: an unchartered cornerstone for understanding the polar ocean circulation and its links to global climate. A key issue facing climate scientists will be addressed: “What sets the tridimensional water-mass structure and pathways in the Weddell Sea and modulates the flow of deep waters between the Antarctica ice-shelves and the global ocean circulation?”
To address this question I propose to investigate several key aspects of the Weddell Sea system: the dynamical forcing of the Weddell gyre and its response to atmospheric variability; the forcing and the circulation on the continental shelf and its interaction with the gyre; and the time-scale and mixing associated with bottom water sinking along the continental shelf. WAPITI approaches these objectives through a series of innovations, including (i) an ambitious field experiment to investigate the shelf circulation and processes, (ii) a powerful conceptual framework applied for the first time to a realistic eddy-resolving model of the Weddell gyre, and (iii) a novel instrument that will be developed to directly observe the sinking of deep water into the abyssal ocean for the first time. Collectively, the project will contribute a new insight into global climate feedbacks.
Fields of science
Programme(s)
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Funding Scheme
ERC-STG - Starting GrantHost institution
75006 Paris
France