Observations of Upwelling and Downwelling Around Antarctica Mediated by Sea Ice
We infer circumpolar maps of stress imparted to the ocean by the wind, mediated by sea-ice, in and around the Seasonal Ice Zone (SIZ) of Antarctica. In the open ocean we compute the wind stress using surface winds from daily atmospheric reanalyses and applying bulk formulae. In the presence of sea i...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2022-06-01
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| Series: | Frontiers in Marine Science |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/articles/10.3389/fmars.2022.864808/full |
| _version_ | 1818202625618739200 |
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| author | Ali Ramadhan John Marshall Gianluca Meneghello Lodovica Illari Kevin Speer |
| author_facet | Ali Ramadhan John Marshall Gianluca Meneghello Lodovica Illari Kevin Speer |
| author_sort | Ali Ramadhan |
| collection | DOAJ |
| description | We infer circumpolar maps of stress imparted to the ocean by the wind, mediated by sea-ice, in and around the Seasonal Ice Zone (SIZ) of Antarctica. In the open ocean we compute the wind stress using surface winds from daily atmospheric reanalyses and applying bulk formulae. In the presence of sea ice, the stress imparted to the underlying ocean is computed from satellite observations of daily ice concentration and drift velocity assuming, first, that the ocean geostrophic currents beneath are negligible, and then including surface geostrophic ocean currents inferred from satellite altimetry. In this way maps of surface ocean stress in the SIZ are obtained. The maps are discussed and interpreted, and their importance in setting the circulation emphasised. Just as in parallel observational studies in the Arctic, we find that ocean currents significantly modify the stress field, the sense of the surface ageostrophic flow and thus pathways of exchange across the SIZ. Maps of Ekman pumping reveal broad patterns of upwelling within the SIZ enhanced near the sea ice edge, which are offset by strong narrow downwelling regions adjacent to the Antarctic continent. |
| first_indexed | 2024-12-12T03:12:26Z |
| format | Article |
| id | doaj.art-a4bbae1841564ae0a3138a6be79ade93 |
| institution | Directory Open Access Journal |
| issn | 2296-7745 |
| language | English |
| last_indexed | 2024-12-12T03:12:26Z |
| publishDate | 2022-06-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Marine Science |
| spelling | doaj.art-a4bbae1841564ae0a3138a6be79ade932022-12-22T00:40:22ZengFrontiers Media S.A.Frontiers in Marine Science2296-77452022-06-01910.3389/fmars.2022.864808864808Observations of Upwelling and Downwelling Around Antarctica Mediated by Sea IceAli Ramadhan0John Marshall1Gianluca Meneghello2Lodovica Illari3Kevin Speer4Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United StatesDepartment of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United StatesDepartment of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United StatesDepartment of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, United StatesGeophysical Fluid Dynamics Institute, Florida State University, Tallahassee, FL, United StatesWe infer circumpolar maps of stress imparted to the ocean by the wind, mediated by sea-ice, in and around the Seasonal Ice Zone (SIZ) of Antarctica. In the open ocean we compute the wind stress using surface winds from daily atmospheric reanalyses and applying bulk formulae. In the presence of sea ice, the stress imparted to the underlying ocean is computed from satellite observations of daily ice concentration and drift velocity assuming, first, that the ocean geostrophic currents beneath are negligible, and then including surface geostrophic ocean currents inferred from satellite altimetry. In this way maps of surface ocean stress in the SIZ are obtained. The maps are discussed and interpreted, and their importance in setting the circulation emphasised. Just as in parallel observational studies in the Arctic, we find that ocean currents significantly modify the stress field, the sense of the surface ageostrophic flow and thus pathways of exchange across the SIZ. Maps of Ekman pumping reveal broad patterns of upwelling within the SIZ enhanced near the sea ice edge, which are offset by strong narrow downwelling regions adjacent to the Antarctic continent.https://www.frontiersin.org/articles/10.3389/fmars.2022.864808/fullSouthern OceanAntarcticaphysical oceanographysea icemeridional overturning circulation |
| spellingShingle | Ali Ramadhan John Marshall Gianluca Meneghello Lodovica Illari Kevin Speer Observations of Upwelling and Downwelling Around Antarctica Mediated by Sea Ice Frontiers in Marine Science Southern Ocean Antarctica physical oceanography sea ice meridional overturning circulation |
| title | Observations of Upwelling and Downwelling Around Antarctica Mediated by Sea Ice |
| title_full | Observations of Upwelling and Downwelling Around Antarctica Mediated by Sea Ice |
| title_fullStr | Observations of Upwelling and Downwelling Around Antarctica Mediated by Sea Ice |
| title_full_unstemmed | Observations of Upwelling and Downwelling Around Antarctica Mediated by Sea Ice |
| title_short | Observations of Upwelling and Downwelling Around Antarctica Mediated by Sea Ice |
| title_sort | observations of upwelling and downwelling around antarctica mediated by sea ice |
| topic | Southern Ocean Antarctica physical oceanography sea ice meridional overturning circulation |
| url | https://www.frontiersin.org/articles/10.3389/fmars.2022.864808/full |
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