The glacial thermohaline circulation: stable or unstable?

The stability of the glacial thermohaline circulation (THC) with respect to North Atlantic freshwater input is examined using a global ocean general circulation model. It is found that the quasi-equilibrium hysteresis behaviour is much less pronounced under glacial conditions than under present-day...

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Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Prange, M., Romanova, V., Lohmann, Gerrit
Format: Article in Journal/Newspaper
Language:unknown
Published: 2002
Subjects:
Online Access:https://epic.awi.de/id/eprint/11055/
https://epic.awi.de/id/eprint/11055/1/Pra2002a.pdf
https://doi.org/10.1029/2002GL015337
https://hdl.handle.net/10013/epic.21515
https://hdl.handle.net/10013/epic.21515.d001
Description
Summary:The stability of the glacial thermohaline circulation (THC) with respect to North Atlantic freshwater input is examined using a global ocean general circulation model. It is found that the quasi-equilibrium hysteresis behaviour is much less pronounced under glacial conditions than under present-day conditions, and the existence of multiple equilibria requires an anomalous freshwater inflow. The results may help to assess the effect of iceberg invasions and meltwater events, suggesting that the THC is prone to instability during a deglaciation phase when the Atlantic meridional overturning is weakened. Under full glacial conditions, however, the THC is mono-stable and even extreme freshwater pulses are unable to exert a persistent effect on the conveyor.