Rapid sea-level rise in the North Atlantic Ocean since the first half of the nineteenth century

A high-resolution late-Holocene sea-level record is produced from salt-marsh deposits at Vioarholmi in Sn ae fellsnes, western Iceland. The stratigraphy of Vioarholmi saltmarsh is documented using detailed descriptions of ten exposed sections and numerous hand-drilled cores. Fossil foraminifera are...

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Bibliographic Details
Published in:The Holocene
Main Authors: Gehrels, Roland W., Marshall, William A, Gehrels, Maria J, Larsen, Gudrun, Kirby, Jason R, Eiriksson, Jon, Heinemeier, J, Shimmield, Tracy
Format: Article in Journal/Newspaper
Language:English
Published: 2006
Subjects:
Geosciences
Multidisciplinary
ICE CORE
SALT-MARSH PONDS
PB ISOTOPE RATIOS
Geography
Physical
LEAD
ICELAND SHELF
SEDIMENTS
HOLOCENE
WESTERN ICELAND
GREENLAND
RECORD
Greenland
ice core
Iceland
North Atlantic
Online Access:https://pure.uhi.ac.uk/en/publications/6b61278d-876e-4f58-a6d1-93d0de6339d1
https://doi.org/10.1177/0959683606hl986rp
Description
Summary:A high-resolution late-Holocene sea-level record is produced from salt-marsh deposits at Vioarholmi in Sn ae fellsnes, western Iceland. The stratigraphy of Vioarholmi saltmarsh is documented using detailed descriptions of ten exposed sections and numerous hand-drilled cores. Fossil foraminifera are used as proxy sea-level indicators in an exposed section of salt-marsh peat. The agglutinated foraminifera Jadammina macrescens and Paratrochammina (Lepidoparatrochammina) haynesi are most useful as sea-level indicators because of their narrow vertical extent on the marsh surface and their good preservation in the peaty marsh deposits. We collected compaction-free sea-level index points from salt-marsh peat directly overlying the bedrock surface to establish the pre-industrial millennial-scale trend of sea-level rise and evaluate effects of autocompaction on the stratigraphy. The chronology of the sea-level reconstruction is based on tephra stratigraphy, AMS C-14, (CS)-C-137, Pb and palaeomagnetic analyses. The main tephra layer visible in the stratigraphy of Vioarholmi salt marsh is the Landnam (settlement) layer, previously dated to AD 875 +/- 6. A sea-transported pumice layer was correlated to the 'Mediaeval Layer' of AD 1226/27. Our reconstruction indicates that relative sea level along the coast of western Iceland has risen by about 1.3 m since C. AD 100. The detrended sea-level record shows a slow rise between AD 100 and 500, followed by a slow downward trend reaching a lowstand in the first half of the nineteenth century. This falling trend is consistent with a steric change estimated from reconstructions of sea-surface and sea-bottom temperatures from shelf sediments off Northern Iceland. The sea-level record shows a marked recent rise of about 0.4 m that commenced AD 1820 +/- 20 as dated by palaeomagnetism and Ph produced by European coal burning. This rapid sea-level rise is interpreted to be related to global temperature rise. The rise has continued up to the present day and has also been measured, since ...

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