The Mighty Susquehanna—Extreme Floods in Eastern North America During the Past Two Millennia

TitleThe Mighty Susquehanna—Extreme Floods in Eastern North America During the Past Two Millennia
Publication TypeJournal Article
Year of Publication2019
AuthorsToomey M, Cantwell M, Colman S, Cronin T, Donnelly J, Giosan L, Heil C, Korty R, Marot M, Willard D
JournalGeophysical Research Letters
Volume46
Issue6
Pagination3398 - 3407
Date PublishedApr-03-2021
ISSN0094-8276
Abstract

The hazards posed by infrequent major floods to communities along the Susquehanna River and the ecological health of Chesapeake Bay remain largely unconstrained due to the short length of streamgage records. Here we develop a history of high‐flow events on the Susquehanna River during the late Holocene from flood deposits contained in MD99‐2209, a sediment core recovered in 26 m of water from Chesapeake Bay near Annapolis, Maryland, United States. We identify coarse‐grained deposits left by Hurricane Agnes (1972) and the Great Flood of 1936, as well as during three intervals that predate instrumental flood records (~1800–1500, 1300–1100, and 400–0 CE). Comparison to sedimentary proxy data (pollen and ostracode Mg/Ca ratios) from the same core site indicates that prehistoric flooding on the Susquehanna often accompanied cooler‐than‐usual winter/spring temperatures near Chesapeake Bay—typical of negative phases of the North Atlantic Oscillation and conditions thought to foster hurricane landfalls along the East Coast.

URLhttps://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018GL080890
DOI10.1029/2018GL080890