Publication Date:
2022-05-26
Description:
Author Posting. © American Geophysical Union, 2006. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 21 (2006): PA4103, doi:10.1029/2006PA001340.
Description:
The temporal relationship between meltwater pulse 1a (mwp-1a) and the climate history of the last deglaciation remains a subject of debate. By combining the Greenland Ice Core Project δ 18O ice core record on the new Greenland ice core chronology 2005 timescale with the U/Th-dated Barbados coral record, we conclusively derive that mwp-1a did not coincide with the sharp Bølling warming but instead with the abrupt cooling of the Older Dryas. To evaluate whether there is a relationship between meltwater injections, North Atlantic Deep Water (NADW) formation, and climate change, we present a high-resolution record of NADW flow intensity from Eirik Drift through the last deglaciation. It indicates only a relatively minor 200-year weakening of NADW flow, coincident with mwp-1a. Our compilation of records also indicates that during Heinrich event 1 and the Younger Dryas there were no discernible sea level rises, and yet these periods were characterized by intense NADW slowdowns/shutdowns. Clearly, deepwater formation and climate are not simply controlled by the magnitude or rate of meltwater addition. Instead, our results emphasize that the location of meltwater pulses may be more important, with NADW formation being particularly sensitive to surface freshening in the Arctic/Nordic Seas.
Description:
R. G. Fairbanks’ sea level and radiometric dating programs
were supported by U.S. NSF grants ATM03-27722 and OCE99-11637.
Keywords:
North Atlantic
;
Deglaciation
;
Overturning
Repository Name:
Woods Hole Open Access Server
Type:
Article
Format:
application/pdf
Format:
text/plain
Format:
image/tiff
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