On freshwater-dependent bifurcations in box models of the interhemispheric thermohaline circulation

Sven Titz; Till Kuhlbrodt; Stefan Rahmstorf; Ulrike Feudel

doi:10.3402/tellusa.v54i1.12126

On freshwater-dependent bifurcations in box models of the interhemispheric thermohaline circulation

Tellus

Volume 54 (2002): Issue 1

By: Sven Titz, Till Kuhlbrodt, Stefan Rahmstorf and Ulrike Feudel

Open Access

|Jan 2002

Abstract

Conceptual box models of the interhemispheric thermohaline circulation are studied with respect to bifurcations. Freshwater fluxes are the main control parameters of the system: they determine the stable states and transitions between stable states of the large-scale thermohaline circulation. In this study of interhemispheric box models both numerical and analytical methods are used to investigate transition mechanisms of the thermohaline circulation. The box model examined first is an interhemispheric four-box model. It is shown that the two bifurcations where the present THC can become unstable, the saddle-node and the Hopf bifurcation, dependin a different way on hemispheric freshwater fluxes. A reduction of the model variables leads to the conclusion that two fixed freshwater fluxes between three surface boxes are the model feature responsible for the bifurcation behaviour found. The significance of the Hopf bifurcation for the stability of the thermohaline circulation is discussed.

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Articles in this issue

DOI: https://doi.org/10.3402/tellusa.v54i1.12126 | Journal eISSN: 3035-9554

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Language: English

Page range: 89 - 98

Submitted on: Mar 28, 2001

Accepted on: Oct 10, 2001

Published on: Jan 1, 2002

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

© 2002 Sven Titz, Till Kuhlbrodt, Stefan Rahmstorf, Ulrike Feudel, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 54 (2002): Issue 1