HR: 0800h
AN: PP31A-0890    [Abstracts]
TI: Holocene Sea-Level Rise in New Jersey and W. North Atlantic Reefs: Untangling Natural and Anthropogenic Effects
AU: * Stanley, A M
EM: Alissams@eden.rutgers.edu
AF: Rutgers, the State University of New Jersey, Department of Geological Sciences, Piscataway, NJ 08854 United States
AU: Miller, K G
EM: kgm@rci.rutgers.edu
AF: Rutgers, the State University of New Jersey, Department of Geological Sciences, Piscataway, NJ 08854 United States
AU: Sugarman, P J
EM: Pete.Sugarman@dep.state.nj.us
AF: New Jersey Geological Survey, PO Box 427, Trenton, NJ 08625 United States
AU: Browning, J V
EM: jvb@rci.rutgers.ed
AF: Rutgers, the State University of New Jersey, Department of Geological Sciences, Piscataway, NJ 08854 United States
AB: The history of pre-anthropogenic Holocene global sea level has not been well constrained. We provide Holocene sea-level estimates for five new boreholes on the New Jersey (NJ) coast (Rainbow Island, Great Bay I, Great Bay II, Cape May, and Island Beach). We analyzed facies, radiocarbon dated marsh deposits, and derived a sea-level record by compiling new and previously published NJ data. Our sea-level record shows a constant rise of $\sim$2 mm/yr from $\sim$7000 yrBP to present. This contrasts sharply with previous NJ estimates that suggested a slowing in rise since 2000 yrBP. Comparison with other NJ locations suggests surprising uniformity in the rate of rise amongst sites as far flung as Cape May and Cheesequake (200 km apart), suggesting a far-field response to the Laurentide ice sheet. The "Barbados/western North Atlantic reefs sea-level" record shows a major decrease in the rate of rise from 12 mm/yr to $\sim$2 mm/yr between 7000 and 8000 yrBP. Data from NJ and western North Atlantic reefs indicate a constant rate of rise of $\sim$2 mm/yr since $\sim$7000 yrBP. This suggests a background, pre-anthropogenic sea-level rise of 2 mm/yr for the entire east coast of the U.S. This background includes both the global (water volume) rise and far-field geoidal subsidence due to removal of the Laurentide ice sheet and water loading (estimated as 1 mm/yr in the modern). Applying the modern subsidence rate to the Holocene suggests a eustatic rise of $\sim$1 mm/yr since 7000 yrBP. Based on tide gauge data, regional sea-level rise averaged 3 mm/yr from 1900-1995, with higher rates (4 mm/yr) locally due to compaction and groundwater withdrawal. We conclude that the anthropogenically induced rise in sea level was $\sim$1 mm/yr from 1900-1995.
DE: 9604 Cenozoic
DE: 4267 Paleoceanography
DE: 1635 Oceans (4203)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2004 AGU Fall Meeting