The Dynamics of the Beaufort Gyre
The Beaufort gyre is located in the Canadian Arctic basin and is responsible for the dominant circulation of the Beaufort Sea. Currently, the gyre flows in an anti-cyclonic direction, which leads to the deflection of fresh water from melting sea ice into the centre due to the Coriolis force. However...
Main Author: | |
---|---|
Format: | Master Thesis |
Language: | English |
Published: |
University of Waterloo
2020
|
Subjects: | |
Online Access: | http://hdl.handle.net/10012/16356 |
id |
ftunivwaterloo:oai:uwspace.uwaterloo.ca:10012/16356 |
---|---|
record_format |
openpolar |
spelling |
ftunivwaterloo:oai:uwspace.uwaterloo.ca:10012/16356 2023-05-15T14:29:19+02:00 The Dynamics of the Beaufort Gyre Webb, Elizabeth 2020-09-19 http://hdl.handle.net/10012/16356 en eng University of Waterloo http://hdl.handle.net/10012/16356 Beaufort Gyre Arctic Ocean ocean fluid dynamics Master Thesis 2020 ftunivwaterloo 2022-06-18T23:03:02Z The Beaufort gyre is located in the Canadian Arctic basin and is responsible for the dominant circulation of the Beaufort Sea. Currently, the gyre flows in an anti-cyclonic direction, which leads to the deflection of fresh water from melting sea ice into the centre due to the Coriolis force. However, every 5 - 7 years it has been observed to reverse direction and release the collected fresh water into Transpolar Drift, towards the Northern Atlantic Ocean. The last recorded reversal was over 20 years ago, and the Beaufort gyre now holds as much fresh water as all the Great Lakes combined. When the next reversal happens, it is predicted that the fresh water will be released and then act as a thick, cold blanket over the Northern Atlantic Ocean, preventing heat transfer to the atmosphere, and greatly affecting the European climate and fisheries. The research in this thesis aims to understand the structure of the Beaufort gyre and how it might destabilize and give rise to eddies. Eddies are known to be very effective in mixing the deep Arctic ocean water with the cold fresh surface water, which could lead to the increased melting of the floating sea ice. In this work we develop numerical tools that can be used to study both the classical wind-driven gyre problem, and also an idealized Beaufort gyre. We use the reduced gravity, Quasi-Geostrophic model, which accounts for the effects of the rotation of earth, wind forcing, bottom drag and lateral viscosity. The solutions are computed using Firedrake, a finite element method library, and we examine how the structure of the steady solution depends on varying values of bottom drag, the beta effect and stratification. Subsequently, we investigate the linear stability of the gyre. Unfortunately, we were not able to simulate winds that are as strong as are observed and as a result did not simulate any instabilities, but the tools have been established for future research. Master Thesis Arctic Basin Arctic Arctic Ocean Beaufort Sea Sea ice University of Waterloo, Canada: Institutional Repository Arctic Arctic Ocean |
institution |
Open Polar |
collection |
University of Waterloo, Canada: Institutional Repository |
op_collection_id |
ftunivwaterloo |
language |
English |
topic |
Beaufort Gyre Arctic Ocean ocean fluid dynamics |
spellingShingle |
Beaufort Gyre Arctic Ocean ocean fluid dynamics Webb, Elizabeth The Dynamics of the Beaufort Gyre |
topic_facet |
Beaufort Gyre Arctic Ocean ocean fluid dynamics |
description |
The Beaufort gyre is located in the Canadian Arctic basin and is responsible for the dominant circulation of the Beaufort Sea. Currently, the gyre flows in an anti-cyclonic direction, which leads to the deflection of fresh water from melting sea ice into the centre due to the Coriolis force. However, every 5 - 7 years it has been observed to reverse direction and release the collected fresh water into Transpolar Drift, towards the Northern Atlantic Ocean. The last recorded reversal was over 20 years ago, and the Beaufort gyre now holds as much fresh water as all the Great Lakes combined. When the next reversal happens, it is predicted that the fresh water will be released and then act as a thick, cold blanket over the Northern Atlantic Ocean, preventing heat transfer to the atmosphere, and greatly affecting the European climate and fisheries. The research in this thesis aims to understand the structure of the Beaufort gyre and how it might destabilize and give rise to eddies. Eddies are known to be very effective in mixing the deep Arctic ocean water with the cold fresh surface water, which could lead to the increased melting of the floating sea ice. In this work we develop numerical tools that can be used to study both the classical wind-driven gyre problem, and also an idealized Beaufort gyre. We use the reduced gravity, Quasi-Geostrophic model, which accounts for the effects of the rotation of earth, wind forcing, bottom drag and lateral viscosity. The solutions are computed using Firedrake, a finite element method library, and we examine how the structure of the steady solution depends on varying values of bottom drag, the beta effect and stratification. Subsequently, we investigate the linear stability of the gyre. Unfortunately, we were not able to simulate winds that are as strong as are observed and as a result did not simulate any instabilities, but the tools have been established for future research. |
format |
Master Thesis |
author |
Webb, Elizabeth |
author_facet |
Webb, Elizabeth |
author_sort |
Webb, Elizabeth |
title |
The Dynamics of the Beaufort Gyre |
title_short |
The Dynamics of the Beaufort Gyre |
title_full |
The Dynamics of the Beaufort Gyre |
title_fullStr |
The Dynamics of the Beaufort Gyre |
title_full_unstemmed |
The Dynamics of the Beaufort Gyre |
title_sort |
dynamics of the beaufort gyre |
publisher |
University of Waterloo |
publishDate |
2020 |
url |
http://hdl.handle.net/10012/16356 |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Basin Arctic Arctic Ocean Beaufort Sea Sea ice |
genre_facet |
Arctic Basin Arctic Arctic Ocean Beaufort Sea Sea ice |
op_relation |
http://hdl.handle.net/10012/16356 |
_version_ |
1766303359044681728 |