Two-way feedback interaction between the thermohaline and wind-driven circulations
نویسندگان
چکیده
The thermohaline circulation (THC) affects the meridional atmospheric temperature gradient and therefore the atmospheric wind and the wind driven ocean circulation. The wind driven circulation (WDC), in turn, affects the THC by the advection of salinity anomalies into deep water formation sites. This paper considers this two way coupling between the WDC and THC, using tools from engineering feedback control. The two way feedback can have a significant effect on the dynamics of the coupled system. For a reasonable choice of parameters, the feedback destabilizes the THC equilibrium for low fresh-water forcing. For higher fresh water forcing, the feedback results in a new stable equilibrium instead of the large amplitude limit cycle that develops without feedback. It is expected that the analysis approach used here may be broadly applicable to the study of feedback interconnections of other climate systems as well.
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