Linking the 8.2 ka event and its freshwater forcing in the Labrador Sea
|Author(s)||Hoffman Jeremy S.2, Carlson Anders E.1, 3, Winsor Kelsey1, Klinkhammer Gary P.4, Legrande Allegra N.5, 6, Andrews John T.7, 8, Strasser Jeffrey C.2|
|Affiliation(s)||1 : Univ Wisconsin, Dept Geosci, Madison, WI 53706 USA.
2 : Augustana Coll, Dept Geol, Rock Isl, IL 61201 USA.
3 : Univ Wisconsin, Ctr Climat Res, Madison, WI 53706 USA.
4 : Oregon State Univ, Coll Earth Ocean & Atmospher Sci, Corvallis, OR 97331 USA.
5 : Columbia Univ, Ctr Climate Syst Res, New York, NY USA.
6 : NASA, Goddard Inst Space Studies, New York, NY 10025 USA.
7 : Univ Colorado, Dept Geol Sci, Boulder, CO 80309 USA.
8 : Univ Colorado, Inst Arctic & Alpine Res, Boulder, CO 80309 USA.
|Source||Geophysical Research Letters (0094-8276) (Amer Geophysical Union), 2012-09 , Vol. 39 , N. 18 , P. L18703 (5p.)|
|WOS© Times Cited||49|
The 8.2 ka event was the last deglacial abrupt climate event. A reduction in the Atlantic meridional overturning circulation (AMOC) attributed to the drainage of glacial Lake Agassiz may have caused the event, but the freshwater signature of Lake Agassiz discharge has yet to be identified in delta O-18 of foraminiferal calcite records from the Labrador Sea, calling into question the connection between freshwater discharge to the North Atlantic and AMOC strength. Using Mg/Ca-paleothermometry, we demonstrate that similar to 3 degrees C of near-surface ocean cooling masked an similar to 1.0 parts per thousand decrease in western Labrador Sea delta O-18 of seawater concurrent with Lake Agassiz drainage. Comparison with North Atlantic delta O-18 of seawater records shows that the freshwater discharge was transported to regions of deep-water formation where it could perturb AMOC and force the 8.2 ka event.