Nineteenth and twentieth century sea-level changes in Tasmania and New Zealand

Positive deviations from linear sea-level trends represent important climate signals if they are persistent and geographically widespread. This paper documents rapid sea-level rise reconstructed from sedimentary records obtained from salt marshes in the Southwest Pacific region (Tasmania and NewZeal...

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Bibliographic Details
Published in:Earth and Planetary Science Letters
Main Authors: Gehrels, W.R., Callard, S.L., Moss, P.T., Marshall, W.A., Blaauw, M., Hunter, J., Milton, J.A., Garnett, M.
Format: Article in Journal/Newspaper
Language:unknown
Published: 2012
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Online Access:http://eprints.gla.ac.uk/63595/
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Summary:Positive deviations from linear sea-level trends represent important climate signals if they are persistent and geographically widespread. This paper documents rapid sea-level rise reconstructed from sedimentary records obtained from salt marshes in the Southwest Pacific region (Tasmania and NewZealand). A new late Holocene relative sea-level record from eastern Tasmania was dated by AMS14C (conventional, high precision and bomb-spike), 137Cs, 210Pb, stable Pb isotopic ratios, trace metals, pollen and charcoal analyses. Palaeosea-level positions were determined by foraminiferal analyses. Relative sealevel in Tasmania was within half a metre of present sealevel for much of the last 6000 yr. Between 1900 and 1950 relative sealevel rose at an average rate of 4.2 ± 0.1 mm/yr. During the latter half of the 20thcentury the reconstructed rate of relative sea-level rise was 0.7 ± 0.6 mm/yr. Our study is consistent with a similar pattern of relative sea-levelchange recently reconstructed for southern NewZealand. The change in the rate of sea-level rise in the SW Pacific during the early 20thcentury was larger than in the North Atlantic and could suggest that northern hemisphere land-based ice was the most significant melt source for global sea-level rise.