2014 GSA Annual Meeting in Vancouver, British Columbia (19–22 October 2014)

Paper No. 182-9
Presentation Time: 10:05 AM

RECONSTRUCTING WESTERN ATLANTIC HOLOCENE HURRICANE IMPACTS FROM TWO COASTAL PONDS IN BERMUDA


WALLACE, Davin J., Division of Marine Science, The University of Southern Mississippi, 1020 Balch Blvd, Stennis Space Center, MS 39529, DONNELLY, Jeffrey P., Geology & Geophysics Department, Woods Hole Oceanographic Institution, MS #22, 266 Woods Hole Rd, Woods Hole, MA 02543 and WOODRUFF, Jonathan D., Department of Geosciences, University of Massachusetts Amherst, 611 North Pleasant St, 233 Morrill Science Center, Amherst, MA 01003

Paleohurricane archives can elucidate current and future hurricane impacts by establishing a geologic and climatic context from numerous sites across the Earth. Due to relatively short instrumental observations in most regions, these records have been useful for interpreting long-term coastal environment evolution and hurricane response to variable climatic and oceanographic conditions in the past. By comparing existing and carefully selected new sites, additional insights can be gained towards a deeper understanding of basin-wide Holocene Atlantic trends. Here we highlight an ongoing paleotempestological project from Mangrove Lake (ML) and Spittal Pond (SP), Bermuda. Due to the unique location of Bermuda in the western Atlantic, these ponds could yield one of the only coastal records of northeastwardly recurving Atlantic storms. These sites have different flooding heights required for inundation and storm deposition, with minimum thresholds of 7 meters (ML) and 3 meters (SP). ML appears to contain a ~4,000 yr B.P. record of intense hurricanes, while Spittal Pond contains a similar ~3,000 yr B.P. record of less intense storms. We will discuss a multiproxy paleotempestological approach consisting of X-radiographs, X-ray fluorescence, and grain size measurements in the context of a short-lived isotope and radiocarbon-derived age model. These sites will provide valuable insight concerning Holocene Atlantic hurricane variability due to North Atlantic Oscillation-like conditions, in addition to quantifying regional trends and responses of storms to oceanographic changes.