Sea-level Change during the Last Thousand Years In Chesapeake Bay


  • Michael S. Kearney


Sea-level rise, Chesapeake Bay, Little Ice Age, radiocarbon dates, paleoclimate, shore erosion


New basal peat dates and older published sea-level indicators for the middle Chesapeake Bay document a very slow overall rate of sea-level rise in this area during the last thousand years, around 0.56 mm/yr. This figure is significantly lower than known rates of subsidence for the mid-Bay region (~1.6-2.0 mm/yr) and implies that most of the last millennium was characterized by a relatively flat sea-level trend punctuated by a major regression. The paleoclimatic record of the late Holocene suggests that the timing of the regression probably coincided with the Little Ice Age. Refining this picture of the recent sea-level history of the middle U.S. Atlantic Coast will require new sea-level information drawn from sources other than marsh sediments, which document regressions poorly due to slowing or cessation of vertical and lateral accretion processes when sea level falls.