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Variability in the El Niño-Southern Oscillation Through
a Glacial-Interglacial Cycle
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Uplifted coral reef terraces of the Huon Peninsula, Papua New Guinea. In this area, the land is moving upwards at a rate of ~2m/1000 years. Consequently, fringing coral reefs along the coast get uplifted, and become sub-aerially exposed. These ancient reefs now form a succession of 'steps', or terraces, in the coastal landscape, with the youngest reefs closest to the coast, and the oldest reefs at higher elevation further back from the coast. The oldest reefs in this image are about 250,000 years old and are seen as terraces towards the top-left of the photo. For our study, we collected fossil corals from reefs up to 130,000 years old, seen here as the terraces from the present-day coast up to the top of the first very distinctive set of cliffs near the middle of the photo. [Photo: Sandy Tudhope] |
Variability in the El Niño-Southern
Oscillation Through a Glacial-Interglacial Cycle Science, v.291(5508), pp 1511-1517, February 23, 2001
Alexander W. Tudhope,1,2* Colin P. Chilcott,1 Malcolm T. McCulloch,3 Edward R. Cook,4 John Chappell,3 Robert M. Ellam,5 David W. Lea,6 Janice M. Lough,2 Graham B. Shimmield7
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1Department of Geology & Geophysics, Edinburgh University, Edinburgh, EH9 3JW, UK. 2Australian Institute of Marine Science, Townsville, Queensland 4810, Australia. 3Research School of Earth Sciences, Australian National University, Canberra, ACT 0200, Australia. 4Tree-Ring Laboratory, Lamont-Doherty Earth Observatory, New York 10964, USA. |
5Scottish Universities Environmental Research Centre, East Kilbride, Glasgow G75 0QF, UK. 6Department of Geological Sciences and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA. 7Dunstaffnage Marine Laboratory, Oban, Argyll, PA34 4AD, UK. *To whom correspondence should be addressed. E-mail: sandy.tudhope@ed.ac.uk |
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ABSTRACT:
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| Walking up through the raised reef terraces on the Huon Peninsula. The scientists are walking on top of Holocene reefs (about 6,000- 10,000 years old), and are going towards older reefs. The ridge at the top of the photograph is the reef crest of the reef that grew ~125,000 years ago during the Last Interglacial. The cliffs and terraces between the scientists and the uppermost ridge are former reefs which grew during the last glacial period [Photo: Sandy Tudhope] | ![]() |
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| Fig. 1. Location of the study sites | ![]() |
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Fig. 3. ENSO variability since 1880. Modern coral skeletal d18O and instrumental climate records have been filtered with a Gaussian bandpass filter to reveal the 2.5- to 7-year (ENSO) components of variability. For all parameters, the polarity of the y axis has been set so that the El Niño phase of the Southern Oscillation would be expected to result in a downward anomaly in the curve. The "local" SST record is the reconstruction for the 1° square centered on 146.5°E, 5.5°S from the GISST2.3b data set of the UK Meteorological Office; the NINO3.4 OS SST is the optimally smoothed SSTreconstruction for the NINO3.4 region in the equatorial central-western Pacific. Darwin sea level pressure and NINO3.4 SST are widely recognized indices of ENSO activity. The pattern of relatively weak and irregular ENSO activity in the middle of the 20th century (but with a major event in the early 1940s) is a well-known feature of historical ENSO variability. Download modern coral data as an Excel file Download modern coral data as individual text files:
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Download fossil coral data as an Excel file Download fossil coral data as individual text files: |
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To read or view the full study, please visit the Science website. It was published in Science Vol. 291, Issue 5508, pp.1511-1517, February 23, 2001. |
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