700 yr sedimentary record of intense hurricane landfalls in southern New England

Abstract

Five intense (category 3 or greater) hurricanes occurring in 1635, 1638, 1815, 1869, and 1938 have made landfall on the New England coast since European settlement. Historical records indicate that four of these hurricanes (1635, 1638, 1815, and 1938) and hurricane Carol, a strong category 2 storm in 1954, produced significant storm surges (>3 m) in southern Rhode Island. Storm surges of this magnitude can overtop barrier islands, removing sediments from the beach and nearshore environment and depositing overwash fans across back-barrier marshes, lakes, and lagoons. In a regime of rising sea level, accumulation of marsh, lake, or lagoon sediments on top of overwash deposits will preserve a record of overwash deposition. We examined the record of overwash deposition at Succotash salt marsh in East Matunuck, Rhode Island, and tested the correlation with historical records of intense storms. Aerial photographs taken after hurricanes in 1954 and 1938 show overwash fans deposited at the site. Analysis of 14 sediment cores from the back-barrier marsh confirmed the presence of these fans and revealed that 4 additional large-scale overwash fans were deposited within the marsh sediments. The four overwash fans deposited since the early seventeenth century at Succotash Marsh matches the historical record of significant hurricane-induced storm surge. These fans were most likely deposited by hurricanes in 1954, 1938, 1815, and either 1638 or 1635. Radiocarbon dating of two prehistoric overwash fans indicated that these were deposited between A.D. 1295– 1407 and 1404–1446 and probably represent intense hurricane strikes. In the past 700 yr, at least 7 intense hurricanes struck the southern Rhode Island coast and produced a storm surge that overtopped the barrier at Succotash Marsh.