Tracking the sea-level signature of the 8.2 ka cooling event: New constraints from the Mississippi Delta

• Published in: Geophysical Research Letters
• Main Authors: Törnqvist, Torbjörn E., Bick, Scott J., Gonzalez, Juan L., van der Borg, Klaas, de Jong, Arie F. M.
• Format: Text
• Language: unknown
• Published: ScholarWorks @ UTRGV 2004
• Subjects: Earth Sciences; Environmental Sciences; Marine Biology; North Atlantic; North atlantic Thermohaline circulation
• Online Access: https://scholarworks.utrgv.edu/eems_fac/51; https://doi.org/10.1029/2004GL021429; https://scholarworks.utrgv.edu/context/eems_fac/article/1051/viewcontent/2004__GL021429.pdf

The ever increasing need for accurate predictions of global environmental change under greenhouse conditions has sparked immense interest in an abrupt, centuryâ€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 nearâ€instantaneous eustatic seaâ€level rise. So far, no attempts have been made to perform highâ€resolution seaâ€level studies that explicitly focus on this critical time interval. Here, we present new data from the Mississippi Delta suggestive of abrupt seaâ€level rise associated with the 8.2 ka event. However, the amount of seaâ€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.