FastFind »   Lastname: doi:10.1029/ Year: Advanced Search  

Geophysical Monograph Series

 

Keywords

  • meltwater
  • Gulf of Mexico
  • foraminifera
  • Younger Dryas
  • Mystery Interval
  • AMOC

Index Terms

  • 1605 Global Change: Abrupt/rapid climate change
  • 4962 Paleoceanography: Thermohaline
  • 1051 Geochemistry: Sedimentary geochemistry
  • 1041 Geochemistry: Stable isotope geochemistry

Article

GEOPHYSICAL MONOGRAPH SERIES, VOL. 193, PP. 39-56, 2011

Laurentide Ice Sheet Meltwater and the Atlantic Meridional Overturning Circulation During the Last Glacial Cycle: A View From the Gulf of Mexico

B. P. Flower

College of Marine Science, University of South Florida, St. Petersburg, Florida, USA


C. Williams

College of Marine Science, University of South Florida, St. Petersburg, Florida, USA


H. W. Hill


D. W. Hastings

Marine Science Discipline, Eckerd College, St. Petersburg, Florida, USA


Meltwater input from the Laurentide Ice Sheet (LIS) has often been invoked as a cause of proximal sea surface temperature (SST) and salinity change in the North Atlantic and of regional to global climate change via its influence on the Atlantic meridional overturning circulation (AMOC). Here we review the evidence for meltwater inflow to the Gulf of Mexico and its reduction relative to the onset of the Younger Dryas, compare inferred meltwater inflow during marine isotope stage 3 (MIS 3), and thereby assess the role of LIS meltwater routing as a trigger of abrupt climate change. We present published and new Mg/Ca and δ18O data on the planktic foraminifer Globigerinoides ruber from four northern Gulf of Mexico sediment cores that provide detailed records of SST and δ18O of seawater (δ18Osw) for most of the last glacial cycle (48–8 ka). These results generally support models that suggest meltwater rerouting away from the Gulf of Mexico and directly to the North Atlantic may have caused Younger Dryas cooling via AMOC reduction. Alternatively, southern meltwater input may simply have been reduced during the Younger Dryas. Indeed, Dansgaard-Oeschger cooling events must have had a different cause because southern meltwater input during MIS 3 does not match their number or timing. Furthermore, the relationships between Gulf of Mexico meltwater input, Heinrich events, Antarctic warm events, and AMOC variability suggest bipolar warming and enhanced seasonality during meltwater episodes. We formulate a “meltwater capacitor” hypothesis for understanding enhanced seasonality during abrupt climate change in the North Atlantic region.

Citation: Flower, B. P., C. Williams, H. W. Hill, and D. W. Hastings (2011), Laurentide Ice Sheet meltwater and the Atlantic meridional overturning circulation during the last glacial cycle: A view from the Gulf of Mexico, in Abrupt Climate Change: Mechanisms, Patterns, and Impacts, Geophys. Monogr. Ser., vol. 193, edited by H. Rashid, L. Polyak and E. Mosley-Thompson, pp. 39–56, AGU, Washington, D. C., doi:10.1029/2010GM001016.

references

Please wait one moment ...

Cited By

Please wait one moment ...