University Department and/or Lab
Department of Earth and Planetary Science, Science Alliance Stable Isotope Laboratory and Laboratory of Tree-Ring Science
My research is on reconstructing tropical cyclone frequency using oxygen isotopes in tree rings in order to extend our understanding of hurricane cycles and their natural and anthropogenic forcings beyond meteorological and historical records.
Description of Research
Hurricanes rank among the most destructive natural disasters that affect the United States. Documentary evidence of hurricane occurrence is limited to instrumental records (~1900) and historical archives (~1700s), making it difficult to observe trends, fluctuations, and causal factors (natural v. anthropogenic) of tropical cyclone activity. To characterize long-term trends, it is necessary to develop proxies that extend the record of hurricane activity beyond historic documents.
Tree-ring oxygen isotope analysis is a useful proxy that allows a seasonal resolution of climatic events. Tropical cyclones have distinct oxygen isotopic signatures that are recorded in the cellulose of tree rings. For my research, I have identified two areas known for having high hurricane frequency: Pensacola, Florida and McClellanville, South Carolina. In these areas, the tree-ring oxygen isotopes captured the meteorologically observed and measured hurricane record very well. Currently, I am pushing the record back into the 1700s, with the potential to extend it into the 1500s.
Example of how my research is integrated into my GK-12 experience
I am integrating my research into my Jefferson County 8th grade classroom by conducting two projects with my students. The current project involves tree-ring dating of a log structure on school grounds, assumed to be the oldest school building in the county. The students spent two days learning basic dendrochronology terms and principles, and techniques such as skeleton plotting and crossdating, while examining many different hand samples. We took core samples from the cabin during class periods and involved all students in photographing the study, taking notes, mounting cores, and making drawings. Another Fellow and I are using our expertise in dendrochronology to do the dating, but the middle-school students have actively participated and are anxious to see the results!
The second project I am developing involves the oxygen isotopes of surface waters and how that relates to site characteristics including latitude, longitude, and physiography. Students will be collecting water from their taps, wells, and streams; purchasing bottled water from different sources; and asking relatives and friends to send water from various locations around the world. We will also use water samples we’ve obtained from the International Ocean Drilling Project. Samples will be analyzed in the Stable Isotope Laboratory at the University of Tennessee, with middle-school students actively participating in sample collection and data analysis. They are excited to see who can get water samples from the most unique location!
Profile date: September 2007