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My Ph.D. work was focused on developing a high resolution (annually resolved) record of hurricane activity for the Boston area based on the varved sedimentary record from the Lower Mystic Lake (Medford/Arlington, MA). This record extends back over the last millennium making it the longest, annually resolved paleotempestology record available from the North Atlantic basin at the moment (July 2008). A paper with results from some of this work was recently published in Geophysical Research Letters, and the paper abstract and full citation follow here.

The annually-laminated (i.e., varved) sediment record from the Lower Mystic Lake (near Boston, MA), contains a series of anomalous graded beds deposited by strong flooding events that have affected the basin over the last millennium. From the historic portion of the record, 10 out of 11 of the most prominent graded beds correspond with years in which category 2–3 hurricanes are known to have struck the Boston area. Thus, we conclude that the graded beds represent deposition related to intense hurricane precipitation combined with wind-driven vegetation disturbance that exposes fresh, loose sediment. The hurricane signal shows strong, centennial-scale variations in frequency with a period of increased activity between the 12th–16th centuries, and decreased activity during the 11th and 17th–19th centuries. These frequency changes are consistent with other paleoclimate indicators from the tropical North Atlantic, in particular, sea surface temperature variations.

Citation: Besonen, M. R., R. S. Bradley, M. Mudelsee, M. B. Abbott, and P. Francus (2008), A 1,000-year, annually-resolved record of hurricane activity from Boston, Massachusetts, Geophys. Res. Lett., 35, L14705, doi:10.1029/2008GL033950.

An electronic reprint of the paper for academic, non-commericial only use by individuals, and not meant for reproduction, is available as Besonen et al. 2008 [GRL].pdf.

Some older figures also related to this work are found below.  Clicking on a thumbnail will bring up a larger version.  Descriptions for the figures, from left to right, are as follows.

1. 15' topo map of Boston area from 1903; the Upper and Lower Mystic Lakes can be seen between Winchester, Medford, and Arlington; the huge increase in urbanization over the last century is clear when comparing this map to the recent air photo of the Mystic Lake/River system at the right
2. a recent airphoto of the Mystic Lake/River system; tidal circulation up and down the Mystic River generally made it to some point past Cradock Dam in Medford during normal circulation, but often reached the lake during high spring and storm tides according to historical documentation; as early as the 1850/60's it was known that the lake was chemically stratified when it was being evaluated as a possible source for fresh water; this makes it one of the earliest meromictic lakes to be described in the United States according to Ludlam and Duval (2001)
3. a 6 cm segment of laminated sediment viewed under plain transmitted and polarized light as a petrographic thin-section, and by X-ray exposure of a 2 mm thick sediment slab (top to left); preliminary varve counts with abritrary, serial numbers can be seen on the thin-section images

Content last updated in July 2008.