American Geophysical Union Become an AGU Member
Subscribe to AGU Journals		 AGU Home AGU Publications

Read Full Article (file size: 743234 bytes)    Cited by

PALEOCEANOGRAPHY, VOL. 18, NO. 2, 1048, doi:10.1029/2002PA000868, 2003

Millennial- to century-scale variability in Gulf of Mexico Holocene climate records

R. Z. Poore

U.S. Geological Survey, Reston, Virginia, USA


H. J. Dowsett

U.S. Geological Survey, Reston, Virginia, USA


S. Verardo

U.S. Geological Survey, Reston, Virginia, USA


T. M. Quinn

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


Abstract

Proxy records from two piston cores in the Gulf of Mexico (GOM) provide a detailed (50–100 year resolution) record of climate variability over the last 14,000 years. Long-term (millennial-scale) trends and changes are related to the transition from glacial to interglacial conditions and movement of the average position of the Intertropical Convergence Zone (ITCZ) related to orbital forcing. The δ18O of the surface-dwelling planktic foraminifer Globigerinoides ruber show negative excursions between 14 and 10.2 ka (radiocarbon years) that reflect influx of meltwater into the western GOM during melting of the Laurentide Ice Sheet. The relative abundance of the planktic foraminifer Globigerinoides sacculifer is related to transport of Caribbean water into the GOM. Maximum transport of Caribbean surface waters and moisture into the GOM associated with a northward migration of the average position of the ITCZ occurs between about 6.5 and 4.5 ka. In addition, abundance variations of G. sacculifer show century-scale variability throughout most of the Holocene. The GOM record is consistent with records from other areas, suggesting that century-scale variability is a pervasive feature of Holocene climate. The frequency of several cycles in the climate records is similar to cycles identified in proxy records of solar variability, indicating that at least some of the century-scale climate variability during the Holocene is due to external (solar) forcing.

Received 25 November 2002; accepted 7 April 2003; published 11 June 2003.

Index Terms: 4267 Oceanography: General: Paleoceanography; 9604 Information Related to Geologic Time: Cenozoic; 3030 Marine Geology and Geophysics: Micropaleontology.

Read Full Article (file size: 743234 bytes)    Cited by

Citation: Poore, R. Z., H. J. Dowsett, S. Verardo, and T. M. Quinn (2003), Millennial- to century-scale variability in Gulf of Mexico Holocene climate records, Paleoceanography, 18(2), 1048, doi:10.1029/2002PA000868.