Thermohaline circulation hysteresis: A model intercomparison

Stefan Rahmstrof, Michel Crucifix, Andrey Ganopolski, Hugues Goosse, Igor Kamenkovich, Reto Knutti, Gerrit Lohmann, Robert Marsh, Lawrence A. Myzak, Zhaomin Wang, Andrew J. Weaver

Research output: Contribution to journalArticle

222 Scopus citations


We present results from an intercomparison of 11 different climate models of intermediate complexity, in which the North Atlantic Ocean was subjected to slowly varying changes in freshwater input. All models show a characteristic hysteresis response of the thermohaline circulation to the freshwater forcing; which can be explained by Stommel's salt advection feedback. The width of the hysteresis curves varies between 0.2 and 0.5 Sv in the models. Major differences are found in the location of present-day climate on the hysteresis diagram. In seven of the models, present-day climate for standard parameter choices is found in the bi-stable regime, in four models this climate is in the mono-stable regime. The proximity of the present-day climate to the Stommel bifurcation point, beyond which North Atlantic Deep Water formation cannot be sustained, varies from less than 0.1 Sv to over 0.5 Sv.

Original languageEnglish (US)
Article numberL23605
Pages (from-to)1-5
Number of pages5
JournalGeophysical Research Letters
Issue number23
StatePublished - Dec 16 2005
Externally publishedYes


ASJC Scopus subject areas

  • Geophysics
  • Earth and Planetary Sciences(all)

Cite this

Rahmstrof, S., Crucifix, M., Ganopolski, A., Goosse, H., Kamenkovich, I., Knutti, R., Lohmann, G., Marsh, R., Myzak, L. A., Wang, Z., & Weaver, A. J. (2005). Thermohaline circulation hysteresis: A model intercomparison. Geophysical Research Letters, 32(23), 1-5. [L23605].