Sea-level variability in the northwest Atlantic during the past 1500 years: A delayed response to solar forcing?

Abstract

Numerical experiments with a coupled ocean-atmosphere model (ECBilt) have shown that centennial variations in sea level (SL) in the northwest Atlantic may be associated with deep-ocean salinity anomalies generated by solar-forced variations in the North Atlantic overturning circulation. Here we compare simulated SL curves for the Gulf Stream region with reconstructed, late-Holocene SL records from Connecticut (USA). Simulated SL variations lag the solar forcing record by ca. 120 year. This lag is found to be robust over a small number of different experiments. The reconstructed SL curves visually match the solar forcing optimally when lagging it by ca. 125 yr. A quantitative test shows that the correlation is significant, while this result is not sensitive to dating uncertainties. The temporal response pattern of the simulated SL curves compares reasonably well with the reconstructions.