Linking the 8.2 ka event and its freshwater forcing in the Labrador Sea

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.

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Text S1. Detailed description of the core site and methodology.
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Figure S1. Hydrography of core site HU87033‐017.
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Table S1. 14C dates used for HU87033‐017.
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Table S2. HU87033‐017 percent sand and calcification temperature.
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Table S3. HU87033‐017 averageδ18Oswat 100‐year resolution.
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How to cite
Hoffman Jeremy S., Carlson Anders E., Winsor Kelsey, Klinkhammer Gary P., Legrande Allegra N., Andrews John T., Strasser Jeffrey C. (2012). Linking the 8.2 ka event and its freshwater forcing in the Labrador Sea. Geophysical Research Letters. 39 (18). L18703 (5p.).,

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