Opening the window to the Southern Ocean: the role of jet dynamics
The surface waters of the Southern Ocean act as a control valve through which climatically important tracers suchas heat, freshwater, and CO2 are transferred between the atmosphere and the ocean. The process that transportsthese tracers through the surface mixed layer into the ocean interior is know...
| Published in: | Science Advances |
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| Main Author: | |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
American Association for the Advancement of Science
2018
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| Subjects: | |
| Online Access: | https://eprints.utas.edu.au/28630/ https://eprints.utas.edu.au/28630/1/128432%20-Opening%20the%20window%20to%20the%20Southern%20Ocean%20the%20role%20of%20jet%20dynamics.pdf |
| Summary: | The surface waters of the Southern Ocean act as a control valve through which climatically important tracers suchas heat, freshwater, and CO2 are transferred between the atmosphere and the ocean. The process that transportsthese tracers through the surface mixed layer into the ocean interior is known as ocean ventilation. Changes inocean ventilation are thought to be important for both rapid transitions of the ocean’s global overturning circulationduring the last deglaciation and the uptake and storage of excess heat and CO2 as a consequence of anthropogenicclimate change. I show how the interaction between Southern Ocean jets, topographic features, andocean stratification can lead to rapid changes in Southern Ocean ventilation as a function of wind stress. For increasingwinds, this interaction leads from a state in which tracers are confined to the surface mixed layer to astate in which tracers fill the ocean interior. For sufficiently high winds, the jet dynamics abruptly change, allowingthe tracer to ventilate a water mass known as Antarctic Intermediate Water in the mid-depth Southern Ocean.Abrupt changes in Antarctic Intermediate Water ventilation have played a major role in rapid climate transitionsin Earth’s past, and combined with the results presented here, this would suggest that jet dynamics could play aprominent role in contributing to, or even triggering, rapid transitions of the global climate system. |
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