TY - JOUR
T1 - Carbon and oxygen isotopic composition of a Guam coral and their relationships to environmental variables in the western Pacific
AU - Asami, Ryuji
AU - Yamada, Tsutomu
AU - Iryu, Yasufumi
AU - Meyer, Christopher P.
AU - Quinn, Terrence M.
AU - Paulay, Gustav
N1 - Funding Information:
We gratefully acknowledge Mr. Adachi, H. of Geoact Corporation and Mr. Akama, S. of C.S. Corporation for drilling corals in Guam, and Mr. Irish, B. and the staff of Marine Laboratory, University of Guam for helping the field investigation in Guam. Deep appreciation is expressed to Professor Hanawa, K. of the Physical Oceanography Laboratory, Department of Geophysics, Graduate School of Science Tohoku University for his helpful advice and providing useful oceanographic data. Our special thanks are due to Dr. Tsuji, Y. and Ms. Shimbo, E. of the Technology Research Center/Japan National Oil Corporation for helping measurements of oxygen isotopic composition of seawater, to Dr. Nakamura, Y. of Division of Environmental Bioremediation, Graduate School of Agriculture, Tohoku University for helping measurements of salinity, and to Mr. Oikawa, T. of Tohoku Historical Museum for taking X-radiographs. The constructive comments and suggestions from Lough, J.M. and the anonymous reviewer were helpful for improving this paper. This study was partially financially supported by Grants-in-Aid for Scientific Research, Japan Society for the Promotion of Science (12304028 to Y.I. and 12740288 to T.Y.), by ‘GCMAPS’ from the Ministry of Education, Culture, Sport, Science and Technology of Japan, by Fujiwara Natural History Foundation, and by the 21st Century Center-Of-Excellence Program, ‘Advanced Science and Technology Center for the Dynamic Earth’, of Tohoku University.
PY - 2004/9/15
Y1 - 2004/9/15
N2 - We examine the high-resolution (∼32 samples/year) carbon and oxygen isotopic composition (δ13Ccoral and δ18Ocoral) in a coral core (Porites lobata) from Double Reef, Guam over the years 1980-2000. The δ13C coral shows clear seasonal variations with mean seasonal amplitude of 1.89‰, which roughly corresponds with seasonal variations in solar radiation. The seasonal amplitude of δ18Ocoral variations are small (0.23-0.57‰), but they are significantly correlated with sea surface temperature (SST) and salinity (SSS). The δ 18Ocoral and SST are more strongly correlated during El Nĩno/Southern Oscillation (ENSO) warm phases (r=-0.81, p<0.01) than during non-ENSO phases (r=-0.65, p<0.01) and ENSO cool phases (r=-0.48, p<0.01). These different relationships are due to differences in winter SST and in seawater δ18O (delta18Osw) during ENSO warm phases (<27°C and higher values of δ18O sw) compared with cool phases (>28°C and lower values of δ18Osw) at Guam. These differences in oceanic parameters result from movements of the Western Pacific Warm Pool (WPWP) during the different phases of ENSO. Anomalies in δ18Osw, inferred from the δ18Ocoral and instrumental SST, are consistent with SSS anomalies for the years 1980-2000. These δ18Osw anomalies may reflect changes in SSS and evaporation-precipitation due to movements of the WPWP. This detailed analysis of a coral from Guam suggests that it may contain an excellent archive of past ENSO events.
AB - We examine the high-resolution (∼32 samples/year) carbon and oxygen isotopic composition (δ13Ccoral and δ18Ocoral) in a coral core (Porites lobata) from Double Reef, Guam over the years 1980-2000. The δ13C coral shows clear seasonal variations with mean seasonal amplitude of 1.89‰, which roughly corresponds with seasonal variations in solar radiation. The seasonal amplitude of δ18Ocoral variations are small (0.23-0.57‰), but they are significantly correlated with sea surface temperature (SST) and salinity (SSS). The δ 18Ocoral and SST are more strongly correlated during El Nĩno/Southern Oscillation (ENSO) warm phases (r=-0.81, p<0.01) than during non-ENSO phases (r=-0.65, p<0.01) and ENSO cool phases (r=-0.48, p<0.01). These different relationships are due to differences in winter SST and in seawater δ18O (delta18Osw) during ENSO warm phases (<27°C and higher values of δ18O sw) compared with cool phases (>28°C and lower values of δ18Osw) at Guam. These differences in oceanic parameters result from movements of the Western Pacific Warm Pool (WPWP) during the different phases of ENSO. Anomalies in δ18Osw, inferred from the δ18Ocoral and instrumental SST, are consistent with SSS anomalies for the years 1980-2000. These δ18Osw anomalies may reflect changes in SSS and evaporation-precipitation due to movements of the WPWP. This detailed analysis of a coral from Guam suggests that it may contain an excellent archive of past ENSO events.
KW - Coral
KW - ENSO
KW - Guam
KW - Stable isotopes
KW - Western Pacific Warm Pool
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U2 - 10.1016/S0031-0182(04)00301-3
DO - 10.1016/S0031-0182(04)00301-3
M3 - Article
AN - SCOPUS:4444308929
SN - 0031-0182
VL - 212
SP - 1
EP - 22
JO - Palaeogeography, Palaeoclimatology, Palaeoecology
JF - Palaeogeography, Palaeoclimatology, Palaeoecology
IS - 1-2
ER -