Interactions of the northern and southern branches of the thermohaline circulation
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 n...
Main Author: | |
---|---|
Language: | unknown |
Published: |
2014
|
Subjects: | |
Online Access: | http://www.osti.gov/servlets/purl/527451 https://www.osti.gov/biblio/527451 https://doi.org/10.2172/527451 |
id |
ftosti:oai:osti.gov:527451 |
---|---|
record_format |
openpolar |
spelling |
ftosti:oai:osti.gov:527451 2023-07-30T04:03:12+02:00 Interactions of the northern and southern branches of the thermohaline circulation McDermott, D.A. 2014-05-13 application/pdf http://www.osti.gov/servlets/purl/527451 https://www.osti.gov/biblio/527451 https://doi.org/10.2172/527451 unknown http://www.osti.gov/servlets/purl/527451 https://www.osti.gov/biblio/527451 https://doi.org/10.2172/527451 doi:10.2172/527451 54 ENVIRONMENTAL SCIENCES OCEANIC CIRCULATION ATMOSPHERIC CIRCULATION CONFIGURATION INTERACTION WIND WATER CURRENTS GENERAL CIRCULATION MODELS OSCILLATIONS MIXING BOX MODELS ATLANTIC OCEAN PACIFIC OCEAN NUMERICAL DATA 2014 ftosti https://doi.org/10.2172/527451 2023-07-11T08:34:39Z 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. The results of the OGCM mixed boundary condition experiments are investigated using simple box models. 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 another, as well as overturning flushes that are followed by a return to the original stable overturning mode. Second, stochastic forcing is applied to the high northern latitude surface fresh water flux. The variations in surface forcing are capable of producing transitions between overturning states that are similar to deep-decoupling oscillations. The stochastic forcing acts to overcome the stabilizing effect of the AABW. In two-basin mixed boundary condition experiments, cooling the climate is seen to result in deep-decoupling type oscillations under stochastic forcing that produced no such variability in a warmer climate. Other/Unknown Material Drake Passage SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Drake Passage Pacific |
institution |
Open Polar |
collection |
SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
op_collection_id |
ftosti |
language |
unknown |
topic |
54 ENVIRONMENTAL SCIENCES OCEANIC CIRCULATION ATMOSPHERIC CIRCULATION CONFIGURATION INTERACTION WIND WATER CURRENTS GENERAL CIRCULATION MODELS OSCILLATIONS MIXING BOX MODELS ATLANTIC OCEAN PACIFIC OCEAN NUMERICAL DATA |
spellingShingle |
54 ENVIRONMENTAL SCIENCES OCEANIC CIRCULATION ATMOSPHERIC CIRCULATION CONFIGURATION INTERACTION WIND WATER CURRENTS GENERAL CIRCULATION MODELS OSCILLATIONS MIXING BOX MODELS ATLANTIC OCEAN PACIFIC OCEAN NUMERICAL DATA McDermott, D.A. Interactions of the northern and southern branches of the thermohaline circulation |
topic_facet |
54 ENVIRONMENTAL SCIENCES OCEANIC CIRCULATION ATMOSPHERIC CIRCULATION CONFIGURATION INTERACTION WIND WATER CURRENTS GENERAL CIRCULATION MODELS OSCILLATIONS MIXING BOX MODELS ATLANTIC OCEAN PACIFIC OCEAN NUMERICAL DATA |
description |
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. The results of the OGCM mixed boundary condition experiments are investigated using simple box models. 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 another, as well as overturning flushes that are followed by a return to the original stable overturning mode. Second, stochastic forcing is applied to the high northern latitude surface fresh water flux. The variations in surface forcing are capable of producing transitions between overturning states that are similar to deep-decoupling oscillations. The stochastic forcing acts to overcome the stabilizing effect of the AABW. In two-basin mixed boundary condition experiments, cooling the climate is seen to result in deep-decoupling type oscillations under stochastic forcing that produced no such variability in a warmer climate. |
author |
McDermott, D.A. |
author_facet |
McDermott, D.A. |
author_sort |
McDermott, D.A. |
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 |
2014 |
url |
http://www.osti.gov/servlets/purl/527451 https://www.osti.gov/biblio/527451 https://doi.org/10.2172/527451 |
geographic |
Drake Passage Pacific |
geographic_facet |
Drake Passage Pacific |
genre |
Drake Passage |
genre_facet |
Drake Passage |
op_relation |
http://www.osti.gov/servlets/purl/527451 https://www.osti.gov/biblio/527451 https://doi.org/10.2172/527451 doi:10.2172/527451 |
op_doi |
https://doi.org/10.2172/527451 |
_version_ |
1772814161256906752 |