Testing the influence of the Central American Seaway on orbitally forced Northern Hemisphere glaciation
نویسندگان
چکیده
[1] Utilizing a climate model of intermediate complexity, we test the hypothesis that the Pliocene closure of the Central American Seaway was a necessary precondition for orbitally triggered Northern Hemisphere glaciation. We conduct a series of sensitivity experiments in order to analyze the isolated and combined effects of Panama closure and orbital forcing on Northern Hemisphere perennial snow cover. While orbital forcing efficiently controls the extension of perennial snow cover, the model results suggest that the closure of the Central American Seaway did not intensify orbitally forced glaciation in high northern latitudes. Citation: Klocker, A., M. Prange, and M. Schulz (2005), Testing the influence of the Central American Seaway on orbitally forced Northern Hemisphere glaciation, Geophys. Res. Lett., 32, L03703, doi:10.1029/2004GL021564.
منابع مشابه
Pliocene oceanic seaways and global climate
Tectonically induced changes in oceanic seaways had profound effects on global and regional climate during the Late Neogene. The constriction of the Central American Seaway reached a critical threshold during the early Pliocene ~4.8-4 million years (Ma) ago. Model simulations indicate the strengthening of the Atlantic Meridional Overturning Circulation (AMOC) with a signature warming response i...
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