RAPID: Collaborative Research: Using the Hurricane Michael Event Layer for Developing a Paleo-Tempestite Archive at Strandplain Swales, St. Vincent Island, Florida

点击翻译按钮获取中文摘要

The project is a rapid-response study of the Hurricane Michael event along the Florida Panhandle coast that experienced the most severe geomorphological impact of this high Category 4 storm in October 2018. Research will focus on collecting cores and samples from sediments deposited by Hurricane Michael on beach ridge swales of St. Joseph Island, Florida and in the area of the Florida Apalachicola Delta. These recently deposited sediments and deposits will have relevance to establishing possible reconstructions of hurricane events over the last ~3,000 years that have impacted this section of the Gulf Coast of the US. Further study of collected sediments and geomorphic changes will help provide detailed information about the frequency, intensity, and wind fields (i.e., direction of storm approach) of strong storms and hurricanes in the past. Broader impacts of the work include student training in rapid response sampling techniques and in providing information that can be used by coastal managers, residents, insurance companies and policy makers regarding the frequency and intensities of hurricanes in this part of the US Gulf Coast. The data collected may also allow inference as to the impacts of human and other environmentally-induced climate change on future hurricanes and the development of new and high-quality proxy records for understanding past storm events.Hurricane Michael, the strongest hurricane known to hit the Florida Gulf Coast, provides an opportunity to examine how a storm event layer (i.e., tempestite) is recorded in strandplain deposits. This research will sample Hurricane Michael deposits on St. Vincent Island, Florida and those in the wetlands of the Apalachicola Delta and adjacent mainland. Project objectives are to (1) map the characteristics (e.g., thickness, granulometry, primary sedimentary structures) of the Michael event layers in the study area as it is expressed across multiple subaerial swales, swale ponds, and coastal wetlands; (2) collect and sample cores of the Hurricane Michael event layer using procedures that will preserve the optically stimulated luminescence signature of the sand fraction; and (3) gather a comprehensive record of ancillary Hurricane Michael datasets from multiple sources (i.e., agencies and individual investigators). Goals are to build a dataset to allow construction of key spatio-temporal parameters shaping the morphological response of coastal systems, like St. Vincent Island, to major storms and how various parameters, such as wind field, storm surge level, wave field, and coastal currents evolved over the course of the storm. The Michael dataset will provide critical information that can aid in recognizing paleo-tempestites in the St. Vincent record, improve our understanding of how optically stimulated luminescence is expressed in hurricane tempestites, and allow calibration of hindcast models of process-geomorphological response that can reconstruct individual paleo-events.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.