Interactions of the northern and southern branches of the thermohaline circulation
Thesis (Ph. D.)--University of Washington, 1996. Coarse resolution models are used to investigate the influence of Southern Hemisphere processes on the Northern branch of the thermohaline circulation. The link between the zonal wind stress at the latitude of Drake Passage and the production of deep...
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ftunivwashington:oai:digital.lib.washington.edu:1773/10055 2024-06-02T08:05:51+00:00 Interactions of the northern and southern branches of the thermohaline circulation McDermott, David A., 1962- 1996 vii, [207] p. http://hdl.handle.net/1773/10055 en_US eng b38308526 37112266 http://hdl.handle.net/1773/10055 Copyright is held by the individual authors. Theses--Atmospheric sciences Thesis 1996 ftunivwashington 2024-05-06T11:39:40Z Thesis (Ph. D.)--University of Washington, 1996. Coarse resolution models are used to investigate the influence of Southern Hemisphere processes on the Northern branch of the thermohaline circulation. The link between the zonal wind stress at the latitude of Drake Passage and the production of deep water in the Northern Hemisphere is explored. A nearly linear response to wind stress at the tip of South America is seen in northern deep water production rates in both one- and two-basin configurations. Transient studies are conducted that illustrate the transmission of the wind generated signal from the Southern Hemisphere to the northern sinking region.Mixed-boundary condition experiments are conducted in a number of model configurations. Deep-decoupling oscillations are produced in a one-hemisphere configuration, but can be suppressed by representing the influence of AABW by restoring the bottom temperatures to appropriate values. In two-hemisphere numerical experiments, the continuous production of AABW is seen to prevent the destabilization of the high northern latitudes, and deep-decoupling oscillations do not occur. In a two-basin configuration, the export of fresh water from the Atlantic basin during a colder climate allows century-scale deep-decoupling oscillations.The results of the OGCM mixed boundary condition experiments are investigated using simple box models. One-hemisphere circulations are generated that are consistent with the 3-D model, and the influence of deep restoring is explored. Deep-decoupling oscillations can only be produced in a two-hemisphere box model if boundary and initial conditions do not allow AABW production. Multiple equilibria are found in the overturning circulation.Two scenarios are presented to produce oscillations that are similar to deep-decoupling oscillations in the presence of continued AABW production. First, the high northern latitudes are subjected to a melt pulse/retreat pattern of freshening. These perturbations can cause transitions from one stable mode to ... Thesis Drake Passage University of Washington, Seattle: ResearchWorks Drake Passage |
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University of Washington, Seattle: ResearchWorks |
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ftunivwashington |
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English |
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Theses--Atmospheric sciences |
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Theses--Atmospheric sciences McDermott, David A., 1962- Interactions of the northern and southern branches of the thermohaline circulation |
topic_facet |
Theses--Atmospheric sciences |
description |
Thesis (Ph. D.)--University of Washington, 1996. Coarse resolution models are used to investigate the influence of Southern Hemisphere processes on the Northern branch of the thermohaline circulation. The link between the zonal wind stress at the latitude of Drake Passage and the production of deep water in the Northern Hemisphere is explored. A nearly linear response to wind stress at the tip of South America is seen in northern deep water production rates in both one- and two-basin configurations. Transient studies are conducted that illustrate the transmission of the wind generated signal from the Southern Hemisphere to the northern sinking region.Mixed-boundary condition experiments are conducted in a number of model configurations. Deep-decoupling oscillations are produced in a one-hemisphere configuration, but can be suppressed by representing the influence of AABW by restoring the bottom temperatures to appropriate values. In two-hemisphere numerical experiments, the continuous production of AABW is seen to prevent the destabilization of the high northern latitudes, and deep-decoupling oscillations do not occur. In a two-basin configuration, the export of fresh water from the Atlantic basin during a colder climate allows century-scale deep-decoupling oscillations.The results of the OGCM mixed boundary condition experiments are investigated using simple box models. One-hemisphere circulations are generated that are consistent with the 3-D model, and the influence of deep restoring is explored. Deep-decoupling oscillations can only be produced in a two-hemisphere box model if boundary and initial conditions do not allow AABW production. Multiple equilibria are found in the overturning circulation.Two scenarios are presented to produce oscillations that are similar to deep-decoupling oscillations in the presence of continued AABW production. First, the high northern latitudes are subjected to a melt pulse/retreat pattern of freshening. These perturbations can cause transitions from one stable mode to ... |
format |
Thesis |
author |
McDermott, David A., 1962- |
author_facet |
McDermott, David A., 1962- |
author_sort |
McDermott, David A., 1962- |
title |
Interactions of the northern and southern branches of the thermohaline circulation |
title_short |
Interactions of the northern and southern branches of the thermohaline circulation |
title_full |
Interactions of the northern and southern branches of the thermohaline circulation |
title_fullStr |
Interactions of the northern and southern branches of the thermohaline circulation |
title_full_unstemmed |
Interactions of the northern and southern branches of the thermohaline circulation |
title_sort |
interactions of the northern and southern branches of the thermohaline circulation |
publishDate |
1996 |
url |
http://hdl.handle.net/1773/10055 |
geographic |
Drake Passage |
geographic_facet |
Drake Passage |
genre |
Drake Passage |
genre_facet |
Drake Passage |
op_relation |
b38308526 37112266 http://hdl.handle.net/1773/10055 |
op_rights |
Copyright is held by the individual authors. |
_version_ |
1800750738955042816 |