Opposite trends in sea-surface salinity and temperature between open-ocean and marginal seas in the tropical Western Pacific during the Holocene

HR: 0800h
AN: PP31D-0652 [Abstracts]
TI: Opposite trends in sea-surface salinity and temperature between open-ocean and marginal seas in the tropical Western Pacific during the Holocene
AU: * Wei, K
EM: weiky@ntu.edu.tw
AF: Dept. of Geosciences, National Taiwan University, PO Box 13-318, Taipei, 106, Taiwan
AU: Chen, C
AF: Dept. of Geosciences, National Taiwan University, PO Box 13-318, Taipei, 106, Taiwan
AU: Chen, M
EM: mtchen@mail.ntou.edu.tw
AF: Inst. of Applied Geosciences, National Taiwan Ocean University, 2, Beining Road, Keelung, 202, Taiwan
AB: The δ¹⁸O profiles of surface sea-waters from the Western Equatorial Pacific (MD982170, MD982176 and MD982181 in Stott et al., 2004) show a common, declining trend (~0.7‰) during the Holocene, reflecting a freshening-up of the tropical Pacific. On the other hand, our newly compiled data show that the sea- waterƒnδ¹⁸O in the South China Sea (MD972142, MD972151), Celebes Sea (MD12380) and Banda Sea (MD12388) increased through the Holocene by ~0.6‰. This suggests that in the western Pacific when the open-ocean has become less saline, the tropical marginal seas have become saltier. The latter phenomenon is consistent with the interpretation that the East Asian monsoon has become weaker during the past 9 ka as suggested by the increasing δ{18}O trend in speleothems of Doggae Cave (Wang et al., 2005) and Shanbao Cave in southern China (Dong et al., 2006). Furthermore, the SSTs in the Western equatorial Pacific have decreased by about 0.6°C during the Holocene (Stott et al., 2004) while the SSTs in the NE South China Sea (MD972142) shows a rising trend of ~1.0°C. On the other hand, the SSTs at other sites of the studied tropical marginal seas do not show any distinctive trends.
DE: 1605 Abrupt/rapid climate change (4901, 8408)
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1626 Global climate models (3337, 4928)
DE: 3344 Paleoclimatology (0473, 4900)
DE: 4901 Abrupt/rapid climate change (1605)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting