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Title: Mixed boundary conditions in ocean general circulation models and their influence on the stability of the model`s conveyor belt

Abstract

When driven under `mixed boundary conditions` coarse resolution ocean general circulation models (OGCMs) generally show a high sensitivity of the present-day thermohaline circulation against perturbations. We will show that an alternative formulation of the boundary condition for temperature, a mixture of prescribed heat fluxes and additional restoring of the sea surface temperature to a climatological boundary temperature with a longer time constant, drastically alters the stability of the modes of the thermohaline circulation. The results from simulations with the Hamburg large-scale geostrophic OGCM indicate that the stability of the mode of the thermohaline circulation with formation of North Atlantic deepwater increases, if the damping of sea surface temperature anomalies is reduced, whereas the opposite is true for the mode without North Atlantic deep water formation. It turns out that the formulation of the temperature boundary condition also affects the variability of the model.

Authors:
;  [1]
  1. Max-Planck-Institut fuer Meteorologie, Hamburg (Germany)
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
45772
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Geophysical Research; Journal Volume: 99; Journal Issue: C11; Other Information: PBD: Nov 1994
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; ATLANTIC OCEAN; HEAT TRANSFER; TEMPERATURE GRADIENTS; OCEANIC CIRCULATION; COMPUTERIZED SIMULATION; BOUNDARY CONDITIONS; WATER CURRENTS; OCEANOGRAPHY

Citation Formats

Mikolajewicz, U., and Maier-reimer, E. Mixed boundary conditions in ocean general circulation models and their influence on the stability of the model`s conveyor belt. United States: N. p., 1994. Web. doi:10.1029/94JC01989.
Mikolajewicz, U., & Maier-reimer, E. Mixed boundary conditions in ocean general circulation models and their influence on the stability of the model`s conveyor belt. United States. doi:10.1029/94JC01989.
Mikolajewicz, U., and Maier-reimer, E. 1994. "Mixed boundary conditions in ocean general circulation models and their influence on the stability of the model`s conveyor belt". United States. doi:10.1029/94JC01989.
@article{osti_45772,
title = {Mixed boundary conditions in ocean general circulation models and their influence on the stability of the model`s conveyor belt},
author = {Mikolajewicz, U. and Maier-reimer, E.},
abstractNote = {When driven under `mixed boundary conditions` coarse resolution ocean general circulation models (OGCMs) generally show a high sensitivity of the present-day thermohaline circulation against perturbations. We will show that an alternative formulation of the boundary condition for temperature, a mixture of prescribed heat fluxes and additional restoring of the sea surface temperature to a climatological boundary temperature with a longer time constant, drastically alters the stability of the modes of the thermohaline circulation. The results from simulations with the Hamburg large-scale geostrophic OGCM indicate that the stability of the mode of the thermohaline circulation with formation of North Atlantic deepwater increases, if the damping of sea surface temperature anomalies is reduced, whereas the opposite is true for the mode without North Atlantic deep water formation. It turns out that the formulation of the temperature boundary condition also affects the variability of the model.},
doi = {10.1029/94JC01989},
journal = {Journal of Geophysical Research},
number = C11,
volume = 99,
place = {United States},
year = 1994,
month =
}
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