Sea-level rise in New Jersey over the past 5000 years: Implications to anthropogenic changes

Abstract

We present a mid to late Holocene sea-level record derived from drilling the New Jersey coast that shows a relatively constant rise of 1.8 mm/yr from ~ 5000 to 500 calibrated calendar years before present (yrBP). This contrasts with previous New Jersey estimates that showed only 0.5 mm/yr rise since 2000 yrBP. Comparison with other Mid-Atlantic sea-level records (Delaware to southern New England) indicates surprising uniformity considering different proximities to the peripheral bulge of the Laurentide ice sheet, with a relative rise throughout the region of ~ 1.7–1.9 mm/yr since ~ 5000 yrBP. This regional sea-level rise includes both: 1) global sea-level (eustatic) rise; and 2) far-field geoidal subsidence (estimated as ~ 0.8–1.4 mm/yr today) due to removal of the Laurentide ice sheet and water loading. Correcting for geoidal subsidence, the U.S. east coast records suggest a global sea-level (eustatic) rise of ~ 0.4–1.0 mm/yr (with a best estimate of 0.7 ± 0.3 mm/yr) since 5000 yrBP. Comparison with other records provides a best estimate of pre-anthropogenic global sea-level rise of < 1.0 mm/yr from 5000 until ~ 200 yrBP. Tide gauge data indicate a 20th century rate of eustatic rise of 1.8 mm/yr, whereas both tide gauge and satellite data suggest an increase in the rate of rise to ~ 3.3 mm/yr from 1993–2006 AD. This indicates that the modern rise (~ 3.3 mm/yr) is significantly higher than the pre-anthropogenic rise (0.7 ± 0.3 mm/yr).