Dune orientation indicates preferential movement during winter with winds dominantly from the W-NW and with reduced vegetation cover. A threshold of landscape stability was exceeded in the late seventeenth to early eighteenth centuries, indicated by dune formation in response to human-induced land-cover changes, concomitant severe droughts and exposure to tropical storm/hurricane windfield. Stratigraphic studies, coupled with optically stimulated luminescence ages, place erosion and burial of the pre-settlement forest soil by migrating dunes at AD 1690 ± 40 yr, with aeolian deposition continuing into the nineteenth and twentieth centuries, consistent with the historic record of land surface conditions. Wetlands expand post dune movement often forming in dune blowouts with seasonally wet conditions. In contrast, dune movement between 19 slowed to ~1 m/yr with wetter conditions. ![]() An aerial photographic time series from AD 1938 to 2003 quantifies dune movement that reflects processes over centuries and documents accelerated parabolic dune movement at ~4 m/yr from 1938 to 1977 during a drier interval. Cape Cod, an early North American colony, was covered by mature forest prior to European contact but, with settlement in the late seventeenth century, aeolian processes dominated into the twenty-first century.
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