Northeastern Section - 36th Annual Meeting (March 12-14, 2001)

Paper No. 6
Presentation Time: 1:30 PM-5:00 PM

DEVELOPMENT OF A 1,200 YEAR LONG HIGH-RESOLUTION RECORD OF HURRICANE ACTIVITY FOR SOUTHERN NEW ENGLAND


BESONEN, Mark R., ABBOTT, Mark B., FRANCUS, Pierre and BRADLEY, Raymond S., Department of Geosciences, Univ of Massachusetts, Morrill Science Center, Amherst, MA 01003, besonen@geo.umass.edu

We are developing a 1,200 year long high-resolution record of hurricane and tropical storm activity for the Boston area based on the sedimentary record archived in the Lower Mystic Lake. The Mystic Lake record is laminated, and appears to contain an annually resolved archive of sedimentation for the last millennium. The lake is directly connected to Boston Harbor by the Mystic River, and has a low surface elevation of just 1 m a.s.l. Overwash and storm surge events that drove marine water inland of Boston Harbor can be detected by changes in sedimentology and diatom assemblages in the sedimentary record. Analysis of the sedimentary record will produce a high-resolution record of such events over the last 1,200 years. We intend to compare this record with a 1 cm resolution loss-on-ignition record we will develop from a marsh in Boston Harbor. Such records are more typical of studies from elsewhere which reconstruct past hurricane frequency based on siliciclastic overwash layers in normal marsh stratigraphy. Comparison of the two records will allow us to determine how accurately each type records overwash events. The frequency of hurricane events will be placed in the context of long-term climate changes. In particular, comparison of the frequency of events over the past millennium during the cold episode of the "Little Ice Age" versus warmer periods may shed light on how hurricane frequencies might be expected to vary under globally warmer conditions in the future.