Ventifact-bearing cover sands, wind-driven lacustrine spits, and fluted bedrock outcrops in New England indicate that a strong anticyclonic circulation under moist periglacial conditions accompanied early recession of the Laurentide ice sheet. Dunes from this interval are conspicuously absent. An abrupt shift to warmer and drier conditions during the Bolling/Allerod period (12.7–11 ka) was apparently associated with rapid accretion of transverse dunes built by northeast winds along the shore of New England's largest ice-recessional lake. By the time of lake drainage, however, the anticyclonic circulation had been replaced by a northwesterly wind regime, resulting in erosion of the older deposits, the development of parabolic dunes, and gradual stabilization associated with revegetation. Reactivation of the dunes was associated with a return to colder and windier conditions during the Younger Dryas (11–10 ka) and with anthropogenic changes during the historic period, but not during Holocene time.

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