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Calibration of Paleoenvironmental Proxy Records for Application to the Holocene Climate Record of the Gulf of Mexico: Kathy Tedesco


Project Title: Calibration of Paleoenvironmental Proxy Records for Application to the Holocene Climate Record of the Gulf of Mexico
Mendenhall Fellow: Kathy Tedesco, kathy.tedesco@gmail.com
Duty Station: St. Petersburg, FL
Start Date: October 29, 2007
Education: Ph.D. (Geological Oceanography), University of South Carolina, 2002
Research Advisors: Richard Poore, (727) 803-8747, x. 3131, rpoore@usgs.gov; Terry Quinn, (512) 471-6381, tquinn@mail.utexas.edu

Project Description: In order to better anticipate future changes in the Earth’s climate, it is necessary to differentiate between natural and anthropogenic influences on the climate system. Paleoclimate reconstructions provide information regarding the timing and magnitude of natural climate variability. One of the primary goals of paleoceanography is the reconstruction of past climates based on the examination of proxy records in marine sediments. The accuracy of reconstructions of past environmental conditions, including temperature and productivity of the ocean, is dependent largely on the reliability of the proxies (Weferand others, 1999). To make optimal use of the information derived from the sediment record, it is necessary to calibrate sedimentary properties to current oceanographic and biological conditions by measuring modern mass fluxes of carbonate, biogenic opal, organic carbon, terrigenous material, microfossil assemblage and shell chemistry (Wefer and others, 1999).

The main objective of this proposal is to contribute to the understanding of Holocene climate variability by calibrating sediment proxy records from the Gulf of Mexico for paleoceanographic reconstructions of the region (fig. 1).
Map of the Glf of Mexico   Figure 1. Map of the Gulf of Mexico showing generalized path of prevailing moisture bearing winds and position of the Intertropical Convergence Zone (ITCZ) for the Northern Hemisphere winter and summer (bold arrows and dashed lines). Generalized position of Loop Current during winter season is shown by light dashed line. From Poore and others (2004).

Specifically, a subsurface sediment trap will be deployed near the Pigmy Basin in the Northern Gulf of Mexico to directly measure the flux and shell chemistry of planktonic foraminifera and sediment geochemistry for comparison with concurrent hydrographic and climatic observations. The results of this study will provide improved calibration of standard proxy measurements leading to improved interpretation and correlation between marine and continental paleoclimate records.

References:

Poore, R.Z., Quinn, T.M., and Verardo, S., 2004, Century-scale movement of the Atlantic Intertropical Convergence Zone linked to solar variability: Geophysical Research Letters, v. 31, L12214, doi:10.1029/2004GL019940.

Wefer, G., Berger, W.H., Bijma, J., and Fischer, G., 1999, Clues to ocean history: A brief overview of proxies, in Fischer, G., and Wefer, G., eds., Use of proxies in [aleoceanography: Examples from the South Atlantic: Berlin, Springer-Verlag, p. 1–68. 


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Last modified: 16:08:33 Thu 13 Dec 2012