A model study of the first ventilated regime of the Arctic Ocean during the early Miocene
The tectonic opening of Fram Strait during the Neogene was a significant geological event that transferred the Arctic Ocean from a poorly ventilated enclosed basin, with weak exchange with the North Atlantic, to a fully ventilated “ocean stage”. Previous tectonic and physical o...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Norwegian Polar Institute
2012-07-01
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| Series: | Polar Research |
| Subjects: | |
| Online Access: | http://www.polarresearch.net/index.php/polar/article/view/10859/pdf_1 |
| _version_ | 1811287222080503808 |
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| author | Bijoy Thompson Martin Jakobsson Johan Nilsson Jonas Nycander Kristofer Döös |
| author_facet | Bijoy Thompson Martin Jakobsson Johan Nilsson Jonas Nycander Kristofer Döös |
| author_sort | Bijoy Thompson |
| collection | DOAJ |
| description | The tectonic opening of Fram Strait during the Neogene was a significant geological event that transferred the Arctic Ocean from a poorly ventilated enclosed basin, with weak exchange with the North Atlantic, to a fully ventilated “ocean stage”. Previous tectonic and physical oceanographic analyses suggest that the early Miocene Fram Strait was likely several times narrower and less than half as deep as the present-day 400 km wide and 2550 m deep strait. Here we use an ocean general circulation model with a passive age tracer included to further address the effect of the Fram Strait opening on the early Miocene Arctic Ocean circulation. The model tracer age exhibits strong spatial gradient between the two major Arctic Ocean deep basins: the Eurasian and Amerasian basins. There is a two-layer stratification and the exchange flow through Fram Strait shows a bi-layer structure with a low salinity outflow from the Arctic confined to a relatively thin upper layer and a saline inflow from the North Atlantic below. Our study suggests that although Fram Strait was significantly narrower and shallower during early Miocene, and the ventilation mechanism quite different in our model, the estimated ventilation rates are comparable to the chemical tracer estimates in the present-day Arctic Ocean. Since we achieved ventilation of the Arctic Ocean with a prescribed Fram Strait width of 100 km and sill depth of 1000 m, ventilation may have preceded the timing of a full ocean depth connection between the Arctic Ocean and North Atlantic established through seafloor spreading and the development of the Lena Trough. |
| first_indexed | 2024-04-13T03:14:56Z |
| format | Article |
| id | doaj.art-10bef4f6db8b49e7964c5cd5efd18cb4 |
| institution | Directory Open Access Journal |
| issn | 0800-0395 1751-8369 |
| language | English |
| last_indexed | 2024-04-13T03:14:56Z |
| publishDate | 2012-07-01 |
| publisher | Norwegian Polar Institute |
| record_format | Article |
| series | Polar Research |
| spelling | doaj.art-10bef4f6db8b49e7964c5cd5efd18cb42022-12-22T03:04:56ZengNorwegian Polar InstitutePolar Research0800-03951751-83692012-07-0131011910.3402/polar.v31i0.10859A model study of the first ventilated regime of the Arctic Ocean during the early MioceneBijoy ThompsonMartin JakobssonJohan NilssonJonas NycanderKristofer DöösThe tectonic opening of Fram Strait during the Neogene was a significant geological event that transferred the Arctic Ocean from a poorly ventilated enclosed basin, with weak exchange with the North Atlantic, to a fully ventilated “ocean stage”. Previous tectonic and physical oceanographic analyses suggest that the early Miocene Fram Strait was likely several times narrower and less than half as deep as the present-day 400 km wide and 2550 m deep strait. Here we use an ocean general circulation model with a passive age tracer included to further address the effect of the Fram Strait opening on the early Miocene Arctic Ocean circulation. The model tracer age exhibits strong spatial gradient between the two major Arctic Ocean deep basins: the Eurasian and Amerasian basins. There is a two-layer stratification and the exchange flow through Fram Strait shows a bi-layer structure with a low salinity outflow from the Arctic confined to a relatively thin upper layer and a saline inflow from the North Atlantic below. Our study suggests that although Fram Strait was significantly narrower and shallower during early Miocene, and the ventilation mechanism quite different in our model, the estimated ventilation rates are comparable to the chemical tracer estimates in the present-day Arctic Ocean. Since we achieved ventilation of the Arctic Ocean with a prescribed Fram Strait width of 100 km and sill depth of 1000 m, ventilation may have preceded the timing of a full ocean depth connection between the Arctic Ocean and North Atlantic established through seafloor spreading and the development of the Lena Trough.http://www.polarresearch.net/index.php/polar/article/view/10859/pdf_1Ocean modellingMiocene Arctic Oceanpalaeoceanographyocean ventilationage tracer |
| spellingShingle | Bijoy Thompson Martin Jakobsson Johan Nilsson Jonas Nycander Kristofer Döös A model study of the first ventilated regime of the Arctic Ocean during the early Miocene Polar Research Ocean modelling Miocene Arctic Ocean palaeoceanography ocean ventilation age tracer |
| title | A model study of the first ventilated regime of the Arctic Ocean during the early Miocene |
| title_full | A model study of the first ventilated regime of the Arctic Ocean during the early Miocene |
| title_fullStr | A model study of the first ventilated regime of the Arctic Ocean during the early Miocene |
| title_full_unstemmed | A model study of the first ventilated regime of the Arctic Ocean during the early Miocene |
| title_short | A model study of the first ventilated regime of the Arctic Ocean during the early Miocene |
| title_sort | model study of the first ventilated regime of the arctic ocean during the early miocene |
| topic | Ocean modelling Miocene Arctic Ocean palaeoceanography ocean ventilation age tracer |
| url | http://www.polarresearch.net/index.php/polar/article/view/10859/pdf_1 |
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