Stability of the Atlantic Meridional Overturning Circulation in the Last Glacial Maximum climate
نویسندگان
چکیده
[1] The stability of the glacial Atlantic Meridional Overturning Circulation is examined using a coupled model of intermediate complexity. Two slightly different climatic states are generated. One has a southward overturning freshwater transport at the southern border of the Atlantic basin, the other a northward transport. Pulse experiments with varying magnitude always result in a collapsed circulation in case of a southward transport, while the overturning recovers in case of a northward transport. In the latter case recovery is due to a positive salinityoverturning feedback, which strengthens the remnant circulation cell that exists in the ‘collapsed’ state. This is amplified by advection by wind-driven currents and a southward ITCZ shift. The glacial circulation is more easily perturbed than the modern and restoring timescales are considerably longer, matching the duration of Heinrich events. Citation: Weber, S. L., and S. S. Drijfhout (2007), Stability of the Atlantic Meridional Overturning Circulation in the Last Glacial Maximum climate, Geophys. Res. Lett., 34, L22706, doi:10.1029/2007GL031437.
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