Holocene Sea-Level Changes along the North Carolina Coastline: Implications for Glacial Isostatic Adjustment Models and Current Rates of Sea-Level Change
We subdivided the late Holocene RSL observations into two regions and compared these with predictions from the ICE-5G(VM2) glacial isostatic adjustment model. The observational data are only fully explicable when rotational feedback is included in the ICE-5G(VM2) model. Rotational feedback increases the rate of sea-level rise in Region 1 (Albemarle, Currituck, Roanoke, Croatan and northern Pamlico sounds), compared to Region 2 (southern Pamlico, Core and Bogue sounds and further south to Wilmington). The observations from Region 1 and 2 show late Holocene sea-level rising at 1.02 ± 0.04 mmyr-1 and 0.92 ± 0.05 mmyr-1, respectively. The ICE-5G(VM2) predictions capture the general temporal trend of the observations, although there is an apparent misfit for index points older than 2000 cal a BP. It is presently unknown whether these misfits derive from possible tectonic uplift associated with the mid-Carolina Platform High.
A comparison of local tide gauge data with the late-Holocene RSL trends imply an additional increase of mean sea-level of greater than 2 mmyr-1 during the latter half of the 20th century; this is in general agreement with historical tide gauge and satellite altimetry data.