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Amplified North Atlantic warming in the late Pliocene by changes in Arctic gateways
Author(s) -
OttoBliesner Bette L.,
Jahn Alexandra,
Feng Ran,
Brady Esther C.,
Hu Aixue,
Löfverström Marcus
Publication year - 2017
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2016gl071805
Subject(s) - arctic dipole anomaly , arctic , oceanography , archipelago , geology , climatology , arctic sea ice decline , arctic geoengineering , arctic ecology , thermohaline circulation , arctic ice pack , drift ice
Under previous reconstructions of late Pliocene boundary conditions, climate models have failed to reproduce the warm sea surface temperatures reconstructed in the North Atlantic. Using a reconstruction of mid‐Piacenzian paleogeography that has the Bering Strait and Canadian Arctic Archipelago Straits closed, however, improves the simulation of the proxy‐indicated warm sea surface temperatures in the North Atlantic in the Community Climate System Model. We find that the closure of these small Arctic gateways strengthens the Atlantic Meridional Overturning Circulation, by inhibiting freshwater transport from the Pacific to the Arctic Ocean and from the Arctic Ocean to the Labrador Sea, leading to warmer sea surface temperatures in the North Atlantic. This indicates that the state of the Arctic gateways may influence the sensitivity of the North Atlantic climate in complex ways, and better understanding of the state of these Arctic gateways for past time periods is needed.