SEA-LEVEL VARIABILITY OVER THE PAST TWO MILLENNIA (NORTH CAROLINA, USA)

We provide continuous, high resolution, reconstructions of sea-level variability for the last 2000 years using detailed composite chronologies and foraminifera from salt‑marsh sedimentary sequences. Removal of a long term rate of glacio-isostatic subsidence allows recognition of sea‑level changes driven by eustatic processes. Four distinct intervals of persistent sea-level variations are identified and compared to established climate records. From at least BC 200 until AD 1000 there was no discernible eustatic change and sea level was in equilibrium with climate. An acceleration to 0.7mm/yr (AD1000‑1350) was coincident with peak Northern Hemisphere air, sea surface and Greenland Ice Sheet temperatures during the Medieval Climate Anomaly and suggests a 300-400 year response time between climatic warming and sea-level rise. A second stable period (AD 1350-1894) reflects a cooler climate associated with expansion of the Greenland Ice Sheet and alpine glaciers during the Little Ice Age. The magnitude of sea-level variations did not exceed 0.30m during the last two millennia until the onset of the modern rate of rise. The timing of this acceleration (AD 1894) is coincident with climate warming and suggests a modified and much reduced response period between climate and sea level in the 20^th century. The rate of sea-level rise during the 20^th century was unprecedented in the last 2000 years.