Date of Award

12-2025

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

School

Ocean Science and Engineering

Committee Chair

Dr. Davin Wallace

Committee Chair School

Ocean Science and Engineering

Committee Member 2

Dr. Christopher Hayes

Committee Member 2 School

Ocean Science and Engineering

Committee Member 3

Dr. Chelsea Pederson

Committee Member 3 School

Ocean Science and Engineering

Committee Member 4

Dr. Joshua Bregy

Committee Member 5

Dr. Elizabeth Wallace

Abstract

This dissertation explores the use of sediment cores as proxy data for the reconstruction of paleoclimatic and environmental conditions. Human-caused climate change is leading to dramatic shifts in the global climate. As the instrumental record of climate is relatively short compared to the amount of time Earth has experienced weather, this work aims to extend our knowledge of climate beyond the instrumental record, thereby improving our holistic understanding of the climate system. In Chapter one, sediment cores from the central Texas inner shelf are used to produce a record of intense tropical cyclone (TC) activity over a ~4500-year period. X-Ray Fluorescence (XRF) and data assimilation are used to bolster depositional and climatic interpretations. Ultimately, sedimentological analyses revealed a long-term annual landfall probability of intense TCs of ~0.53%.

Chapter two is a ~4000-year record of intense TC activity at Dauphin Island, Alabama, located along the northern Gulf of Mexico (GOM). In this research, sediment cores from the subaqueous backbarrier are used as archives of overwash produced from TC impacts. Similar to Chapter 1, grain size and statistical threshold analysis yield discrete, intense TC impacts over the span of the record. In addition, inverse sediment transport modeling is used to reconstruct the flooding intensities relating to each event. Interestingly, over the length of this record, the highest frequency of intense TC impacts (events per century) occurred after 1900 CE.

Chapter three uses a sediment core from a reef hole near Bohol, Philippines, to present new applications to reconstruct paleoclimate and depositional histories. Stable oxygen isotopes of benthic foraminifera genera: Spiroloculina spp. and Elphidium spp. are used alongside data assimilation and reanalysis data to reconstruct SST over an ~800-year record. In addition, XRF and data assimilation reveal a connection between local hydroclimate and earthquake activity in the region. Given the abundance of benthic foraminifera in coastal waters around the globe, similar methods may be used to increase the number of paleoclimate and paleoenvironmental archives.

Download

  Contact Author

Share

COinS