Show simple item record

dc.contributor.authorCohen, Anne L.  Concept link
dc.contributor.authorHart, Stanley R.  Concept link
dc.date.accessioned2010-05-12T14:16:17Z
dc.date.available2010-05-12T14:16:17Z
dc.date.issued2004-12-30
dc.identifier.citationPaleoceanography 19 (2004): PA4031en_US
dc.identifier.urihttps://hdl.handle.net/1912/3436
dc.descriptionAuthor Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 19 (2004): PA4031, doi:10.1029/2004PA001084.en_US
dc.description.abstractUsing Secondary Ion Mass Spectrometry (SIMS) ion microprobe techniques, we generated annual Sr/Ca cycles with subweekly resolution from chunks of Porites coral retrieved from a Tahiti barrier reef drill core (149°W, 17°S), representing the period 13,650 to 13,100 years B.P. The centers of pristine skeletal septa were selectively targeted with a 10 μm diameter ion beam spot, avoiding adjacent pore spaces occupied by secondary aragonite needles. Applying a Sr/Ca–sea surface temperature (SST) calibration equation derived from modern Tahiti Porites having the same low growth rate as the fossil specimens, we obtained SSTs ∼0.5°–1.5°C cooler during the Bølling-Allerod relative to the present day, with no significant change in seasonality. On the contrary, we estimate that analysis of bulk samples would yield excessively cool Sr/Ca-based SST estimates due to the occupation by secondary aragonite crystals of up to 50% of the skeletal pore space in the ancient samples. We find that growth rate effects on coral Sr/Ca further depress the apparent mean annual derived SSTs (by >3°C) and amplify the apparent seasonality by selectively enhancing wintertime cooling. Our microscale analysis of pristine skeleton and application of an appropriate growth-dependent calibration yield Sr/Ca-derived SSTs that are in good agreement with those derived from Mg/Ca ratios of calcitic foraminifera which indicate a continuous postglacial warming of the western tropical Pacific, in phase with the warming of the tropical Atlantic.en_US
dc.description.sponsorshipFunds for this study were provided by NSF MG&G award number OCE-0241075.en_US
dc.format.mimetypeapplication/pdf
dc.language.isoen_USen_US
dc.publisherAmerican Geophysical Unionen_US
dc.relation.urihttps://doi.org/10.1029/2004PA001084
dc.subjectTropical Pacificen_US
dc.subjectSea surface temperatureen_US
dc.subjectBølling-Alleroden_US
dc.subjectCoral Sr/Caen_US
dc.subjectIon microprobeen_US
dc.subjectDiagenesisen_US
dc.titleDeglacial sea surface temperatures of the western tropical Pacific : a new look at old coralen_US
dc.typeArticleen_US
dc.identifier.doi10.1029/2004PA001084


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record