A snapshot of climate variability at Tahiti ~ 9 ka using a fossil coral from IODP Expedition 310

Kristine L DeLong; Terrence M. Quinn; Chuan-Chou Shen; Ke Lin

doi:10.1029/2009gc002758

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A snapshot of climate variability at Tahiti ~ 9 ka using a fossil coral from IODP Expedition 310

Kristine L DeLong·Terrence M. Quinn·Chuan-Chou Shen·Ke Lin

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Abstract

The Integrated Ocean Drilling Program (IODP) Expedition 310 recovered drill cores from the drowned reefs around the island of Tahiti (17°40′S, 149°30′W), many of which contained samples of massive corals from the genus Porites . Herein we report on one well-preserved fossil coral sample: a 13.6 cm long Porites sp. dated by uranium series techniques at 9523 ± 33 years. Monthly δ 18 O and Sr/Ca determinations reveal nine clear and robust annual cycles. Coral δ 18 O and Sr/Ca determinations estimate a mean temperature of ∼24.3°C (∼3.2°C colder than modern) for Tahiti at 9.5 ka; however, this estimate is viewed with caution since potential sources of cold bias in coral geochemistry remain to be resolved. The interannual variability in coral δ 18 O is similar between the 9.5 ka coral record and a modern record from nearby Moorea. The seasonal cycle in coral Sr/Ca is approximately the same or greater in the 9.5 ka coral record than in modern coral records from Tahiti. Paired analysis of coral δ 18 O and Sr/Ca indicates cold/wet (warm/dry) interannual anomalies, opposite from those observed in the modern instrumental record.

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Geochemistry, Geophysics, Geosystems Article

Source-reported bounding extent: -17.956825850324933° to -17.37818620895858° latitude; -149.97340625761515° to -149.0404249716099° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Kristine L DeLong, Terrence M. Quinn, Chuan-Chou Shen, Ke Lin. 2010-06-08. A snapshot of climate variability at Tahiti ~ 9 ka using a fossil coral from IODP Expedition 310. https://doi.org/10.1029/2009gc002758

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