Kikai Island Coral Radiocarbon and Oxygen Isotope Data --------------------------------------------------------------------- NOAA Paleoclimatology Program and World Data Center for Paleoclimatology, Boulder --------------------------------------------------------------------- NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!! NAME OF DATA SET: Kikai Island Coral Radiocarbon and Oxygen Isotope Data LAST UPDATE: 11/2004 (Original Receipt by WDC Paleo) CONTRIBUTOR: Maki Morimoto, Nagoya University IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2004-081 SUGGESTED DATA CITATION: Morimoto, M. et al.. 2004. Kikai Island Coral Radiocarbon and Oxygen Isotope Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series #2004-081. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Morimoto, M., H. Kitagawa, Y. Shibata, and H. Kayanne. 2004. Seasonal radiocarbon variation of surface seawater recorded in a coral from Kikai Island, subtropical Northwestern Pacific. Radiocarbon, 46-2, 643-648. ABSTRACT: A coral radiocarbon (D14C) investigation with a high time-resolution is crucial for reconstructing secular and seasonal D14C changes in the surface seawater, which potentially reflect ocean circulations and dynamic ocean-atmosphere interactions. The D14C 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 D14C 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 D14C was about 18 per mil on the average, and minimum D14C was observed in late spring and summer. The D14C changes were tentatively explained by horizontal oceanic advections around Kikai Island or over the wide range of the equatorial and subequatorial Pacific. GEOGRAPHIC REGION: Western Pacific PERIOD OF RECORD: 1991 to 1998 AD DESCRIPTION: Coral radiocarbon and oxygen isotope data at monthly resolution from Kikai Island, Japan for 1991 to 1998. A 25-cm-diameter colony of Porites sp. was collected at the water depth of 2.9 m (msl) at Araki, on the southwestern coast of the Island. (28 deg, 17.2'N, 129 deg. 55.6'E). Samples for measurements were drilled out from the coral slab at 1.2-mm intervals for d18O and at 1.5-mm for D14C. The chronology has been established by fitting coral d18O peaks, both in summer and winter, to the 3-week-averaged SST maximums and minimums, assuming linear extension rates between peaks. DATA: 1. Kikai coral radiocarbon Column 1: Calendar Year A.D. Column 2: D14C (permil) Year A.D D14C 1998.54 90 1998.47 78 1998.39 86 1998.32 93 1998.25 94 1998.17 91 1998.1 88 1998.04 88 1997.98 96 1997.91 92 1997.85 101 1997.78 94 1997.72 97 1997.65 84 1997.56 81 1997.46 1997.37 93 1997.28 86 1997.19 87 1997.11 92 1997.04 97 1996.98 1996.92 104 1996.85 100 1996.78 96 1996.72 100 1996.65 81 1996.59 80 1996.47 87 1996.34 94 1996.22 106 1996.13 103 1996.06 106 1995.99 101 1995.92 95 1995.84 101 1995.77 97 1995.7 95 1995.63 103 1995.56 97 1995.48 88 1995.41 94 1995.34 88 1995.27 99 1995.2 98 1995.12 99 1995.04 105 1994.96 103 1994.88 107 1994.8 104 1994.72 95 1994.64 108 1994.56 105 1994.48 101 1994.39 98 1994.31 104 1994.23 106 1994.15 95 1994.07 110 1994 109 1993.93 102 1993.86 108 1993.79 106 1993.72 97 1993.64 111 1993.57 107 1993.51 100 1993.45 98 1993.4 99 1993.35 101 1993.29 106 1993.24 113 1993.18 113 1993.06 113 1992.95 105 1992.84 114 1992.73 112 1992.61 109 1992.53 114 1992.48 112 1992.43 115 1992.38 106 1992.33 103 1992.28 99 1992.23 108 1992.18 108 1992.12 113 1992.05 114 1991.98 122 1991.91 123 1991.83 110 1991.76 122 1991.69 113 1991.62 118 1991.55 123 1991.48 112 1. Kikai coral oxygen isotopes Column 1: Calendar Year A.D. Column 2: d18O (permil VPDB) Year A.D. d18O 1998.55 -5.3 1998.49 -5.14 1998.43 -4.98 1998.37 -4.76 1998.31 -4.4 1998.25 -4.04 1998.19 -4.01 1998.13 -3.97 1998.08 -4.17 1998.03 -4.28 1997.98 -4.44 1997.93 -4.64 1997.88 -4.85 1997.83 -4.99 1997.78 -5 1997.73 -5.08 1997.68 -5.28 1997.6 -5.16 1997.53 -4.97 1997.45 -4.68 1997.38 -4.71 1997.31 -4.41 1997.23 -3.98 1997.16 -3.86 1997.1 -3.91 1997.05 -3.96 1997 -4.28 1996.95 -4.43 1996.9 -4.59 1996.84 -4.84 1996.79 -5.17 1996.74 -5.2 1996.69 -5.09 1996.64 -5.2 1996.58 -5.26 1996.48 -5.05 1996.38 -4.5 1996.28 -4.13 1996.18 -3.68 1996.12 -3.7 1996.07 -3.91 1996.01 -4.22 1995.95 -4.4 1995.9 -4.69 1995.84 -4.95 1995.78 -5.03 1995.72 -5.08 1995.67 -5.24 1995.61 -5.37 1995.55 -5.25 1995.49 -5.16 1995.44 -5.15 1995.38 -4.93 1995.32 -4.53 1995.26 -4.29 1995.21 -3.82 1995.15 -3.78 1995.08 -4.07 1995.02 -4.25 1994.96 -4.51 1994.89 -4.66 1994.83 -4.84 1994.76 -5.05 1994.7 -5.17 1994.64 -5.19 1994.57 -5.35 1994.5 -5.31 1994.44 -5.27 1994.37 -4.97 1994.3 -4.68 1994.24 -4.36 1994.17 -3.77 1994.11 -3.85 1994.05 -4.14 1994 -4.49 1993.94 -4.68 1993.88 -4.69 1993.82 -4.87 1993.77 -5.03 1993.71 -5.01 1993.65 -5.21 1993.59 -5.17 1993.54 -5.26 1993.49 -5.22 1993.45 -5.07 1993.41 -4.73 1993.36 -4.41 1993.32 -4.04 1993.28 -3.79 1993.23 -3.9 1993.19 -3.74 1993.1 -4.04 1993.01 -4.32 1992.92 -4.51 1992.83 -4.73 1992.74 -4.88 1992.65 -5.15 1992.56 -5.24 1992.52 -5.09 1992.48 1992.44 -5.22 1992.4 -5.06 1992.36 -4.79 1992.32 -4.67 1992.28 -4.49 1992.24 -4.1 1992.19 -3.88 1992.16 -3.85 1992.1 -4.02 1992.04 1991.99 -4.49 1991.93 -4.8 1991.87 -5 1991.81 -5.28 1991.76 -5.33 1991.7 -5.35 1991.64 -5.23 1991.58 -5.44 1991.53 -5.33 1991.47 -5.31 1991.41 -5.24 1991.35 -4.76 1991.3 -4.38