HR: 10:35h
AN: PP32A-02 [Abstracts]
TI: Select, High-Resolution Windows Into Sub-Centennial-Scale Climate Variability in the Western Pacific
Warm Pool Between 7 and 12 ka
AU: * Quinn, T M
EM: quinn@marine.usf.edu
AF: College of Marine Science, Univ. South Florida, 140 7th Ave., South, MSL 119, St. Petersburg, FL 33701
United States
AU: Taylor, F W
EM: fred@utig.ig.utexas.edu
AF: Institute for Geophysics, The John A. and Katherine G. Jackson School of Geosciences, The Univ. of Texas
at Austin, 4412 Spicewood Springs Rd., Austin, TX 78759-8500
United States
AU: Cheng, H
EM: cheng021@umn.edu
AF: Department of Geology and Geophysics, University of Minnesota, 310 Pillsbury Drive Southeast,
Minneapolis, MN 55455
United States
AU: Edwards, R L
EM: edwar001@umn.edu
AF: Department of Geology and Geophysics, University of Minnesota, 310 Pillsbury Drive Southeast,
Minneapolis, MN 55455
United States
AU: Burr, G
EM: burr@physics.arizona.edu
AF: NSF Accelerator Facility, Department of Physics, University of Arizona, 1118 E. 4th Street, PO Box
210081, Tucson, AZ 85721
United States
AU: Chen, Y
EM: ygchen@ccms.ntu.edu.tw
AF: Dept. of Geosciences, National Taiwan University, No.1, Sec. 4, Roosevelt Road, Tapei, 106
Taiwan
AB:
Post-glacial, coral-based climate records from the Western Pacific Warm Pool (WPWP), a region that serves as a major heat and
moisture source to the ocean-atmosphere system, provide sub-annually resolved windows into climate variability on
interannual to multi-decadal timescales from this climatologically significant region. Paleoclimate reconstructions based on
fossil corals require that the skeletal geochemistry be unaffected by diagenesis and that secular changes in seawater
chemistry be known. Global seawater \delta$^{18}$O variations can be constrained using knowledge of past variations in ice
volume, whereas much less is known about global seawater Sr/Ca variations, if they occur in the post-glacial interval. Our
paleoclimate reconstructions are based on monthly resolved \delta$^{18}$O and Sr/Ca records in fossil Porites corals from the
Western Solomon Islands ($\sim$$8\deg$ S, $\sim$$157\deg$ E; Tetepare and Rendova). Post-depositional alteration of our
fossil coral samples is minimal based on mineralogic (XRD), petrographic (SEM) and geochemical criteria (preservation of
modern marine initial \delta$^{234}$U values). Four of these fossil coral time series are of particular interest: 99RND
(age, 7,992$\pm$42; ~45 years), 01T-B (age, 7,647$\pm$73; ~65 years), 01T-AQ (age, 10,208$\pm$44; ~30 years), and 99TET-B
(age, 11,987$\pm$69; ~ 30 years). We apply a model that uses simultaneous variations in coral \delta$^{18}$O and Sr/Ca in
combination with estimates of post-glacial changes in seawater chemistry to reconstruct mean climate state during the early
Holocene and the Younger Dryas. Model results indicate that on average SSTs in the WPWP were within $1\deg$C of modern and
that surface waters were more saline than modern during each of the four time intervals during which our fossil corals grew.
DE: 3344 Paleoclimatology
DE: 4215 Climate and interannual variability (3309)
DE: 3309 Climatology (1620)
DE: 1620 Climate dynamics (3309)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2004 AGU Fall Meeting