North-South Connections

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This behavior is sometimes called “antiphasing” between north and south. The term “antiphasing” ignores, however, the fact that adjustment to thermal anomalies in the Southern Hemisphere evolves qualitatively differently from that in the north. Because of the large thermal heat capacity of the Southern Ocean, an abrupt cooling in the Northern Hemisphere due to a collapse ot the THC within less than a decade leads to a millennial warming trend in the south Atlantic.

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This work is supported by the European Commission project POP. I thank G. Schmidt and M. Vellinga for providing data from their model runs; R. Pawlowicz for producing and sharing Matlab code for geophysical mapping; and T. Blunier, G. Delaygue, J. Jouzel, V. Masson, G. Raisbeck, J. Schwander, B. Stauffer, T. van Ommen, and F. Vimeux for valuable discussions.