American Geophysical Union, Geophysical Research Letters, 23(31), 2004
DOI: 10.1029/2004gl021429
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The ever increasing need for accurate predictions of global environmental change under greenhouse conditions has sparked immense interest in an abrupt, century-scale cooling around 8200 years ago, with a focal point in the North Atlantic and with hemispheric teleconnections. Despite considerable progress in the unraveling of this striking feature, including a conceivable driving mechanism (rapid drainage of proglacial Lake Agassiz/Ojibway and a resulting reduced strength of North Atlantic thermohaline circulation), several key questions remain unanswered. One salient aspect concerns the total amount of freshwater released during this catastrophic event, likely echoed by a near-instantaneous eustatic sea-level rise. So far, no attempts have been made to perform high-resolution sea-level studies that explicitly focus on this critical time interval. Here, we present new data from the Mississippi Delta suggestive of abrupt sea-level rise associated with the 8.2 ka event. However, the amount of sea-level rise was likely less than ∼1.2 m, corresponding to a meltwater volume of less than ∼4.3 1014 m3; values lower than estimates used by several recent studies.