Research Interests

My research interests lie in understanding Earth's climate history. Better predictions of future climate change are dependent upon understanding Earth's climate system, but existing instrumental climate records do not span enough time to fully understand the climate system, especially at time scales longer than a few decades and under conditions of changing background climate state. That is where geologic archives of Earth's climate can be of use. Different archives have different strengths and weaknesses, and for my graduate research, I have focused on using the geochemistry of corals to reconstruct temperature and hydrologic variability in the tropics.

Some question exists as to the permanence of the El Nino-Southern Oscillation (ENSO), especially during times of different background climate states. For my Masters research, I was able to use the chemistry of corals from Espiritu Santo Island, Republic of Vanuatu to reconstruct both mean climate state, and interannual variability over much of the 20th century and during a ~13-year time window from a fossil coral which grew approximately 350 thousand years ago. The Republic of Vanuatu is situated beneath the South Pacific Convergence Zone (SPCZ) which can be considered the upward limb of Walker Circulation and is integrally tied to ENSO. The fossil coral sample revealed evidence of the ENSO phenomenon in the southwest tropical Pacific. It also indicated that conditions were generally cooler and that the SPCZ may have been directly over Vanuatu more of the year, causing lower mean salinity values and a decrease in the seasonal variations of seawater d18O. The results of this study were published in 2004 by the journal Paleoceanography (links to the papers are below). The first paper describes the work on the fossil coral, while the second paper focuses on using corals for reconstructing hydrologic changes related to ENSO in this area.

The focus of my Ph.D. research is climate variability in Tropical North Atlantic and Caribbean Sea over the last two centuries. My collaborators and I hope to answer three fundamental questions:

1) What is the nature of climate variability in the Greater Antilles sector of the Caribbean over the last ~200 years?
2) How have the contributions of various source waters to the Gulf Stream current system varied over the same time period?
3) What impact do changes in Tropical Atlantic/Caribbean Sea climate have on the extra-tropical North Atlantic?

Field work took place in August of 2004 and data generation is in its final stages. Initial results were presented in San Francisco at the Fall 2005 American Geophysical Union meeting. In October of 2005, I spent a month at Lawrence Livermore National Laboratory’s Center for Accelerator Mass Spectrometry generating 14C data on a coral from Puerto Rico. These data are being used to examine circulation changes in the Caribbean and investigate the relationship between those circulation changes and climate variability as measured from the same coral. Manuscripts on my Caribbean work will be coming out soon as I plan to finish my Ph. D. by summer, and I am currently in the market for postdoctoral positions beginning in the Fall of 2006.



Publications & Presentations

Kilbourne, K., Quinn, T.M., Taylor, F., Delcroix, T., Gouriou, Y., 2004. ENSO-related Salinity Variations Recorded in the Skeletal Geochemistry of a Porites Coral from Espiritu Santo, Vanuatu. Paleoceanography, Vol. 19, No. 4, PA4002 10.1029/2004PA001033. abstract (html) or full text (pdf 532kb)

Kilbourne, K.H., Quinn, T.M., Taylor, F.W., 2004. A fossil coral perspective on western tropical Pacific climate ~350 ka. Paleoceanography, 19, 1, PA1019, 10.1029/2003PA000944. abstract (html) or full text (.pdf 544kb) * Highlighted in Science Editor's Choice (March 26, 2004)