Seasonal Radiocarbon Variation of Surface Seawater Recorded in a Coral from Kikai Island, Subtropical Northwestern Pacific
C 14 C 12
O 18 O 16
sea surface temperature
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CitationMorimoto, M., Kitagawa, H., Shibata, Y., & Kayanne, H. (2004). Seasonal radiocarbon variation of surface seawater recorded in a coral from Kikai Island, subtropical northwestern Pacific. Radiocarbon, 46(2), 643-648.
DescriptionFrom the 18th International Radiocarbon Conference held in Wellington, New Zealand, September 1-5, 2003.
AbstractA coral radiocarbon (Delta-14C) investigation with a high time-resolution is crucial for reconstructing secular and seasonal Delta-14C changes in the surface seawater which potentially reflect ocean circulations and dynamic ocean-atmosphere interactions. The Delta-14C values of a modern coral (Porites sp.) from Kikai Island, southern Japan, in the subtropical northwestern Pacific, were determined for the period of 1991-1998 at a monthly resolution. A coral Delta-14C time series for the 8 yr indicated seasonal cycles superimposed on a secular decreasing trend of 3.8 per mil per yr. The seasonal amplitude of the coral Delta-14C was about 18 per mil on the average and the minimum Delta-14C was observed in late spring and summer. The Delta-14C changes were tentatively explained by horizontal oceanic advections around Kikai Island or over the wide range of the equatorial and subequatorial Pacific.
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