Reliability of coral isotope records from the Western Pacific Warm Pool: A comparison using age‐optimized records

Stable isotope analysis of two separate corals from Nauru Island in the warm pool of the western tropical Pacific confirm that coral oxygen isotopes are a robust recorder of environmental variables. Coral delta(18)O faithfully records interannual variability even when strongly influenced by kinetic effects. Interannual to decadal variability of coral delta(13)C remains enigmatic; only one of the two corals exhibits the expected light-delta(13)C response in the interannual band. Coral delta(18)O from this region has a great similarity to global instrumental temperature records reflecting the impact of the Pacific warm pool and variations of the Indonesian Low in concert with El Nino-Southern Oscillation on global climate. Since 1896, coral delta(18)O has exhibited a cumulative decrease of 0.7 parts per thousand, which reflects a combination of warming and more frequent El Nino events (precipitation) affecting the surface waters of this region.

[1]  T. Guilderson,et al.  Seasonal variations in the boron isotopic composition of coral: A productivity signal? , 1998 .

[2]  D. Schrag,et al.  Radiocarbon variability in the western equatorial Pacific inferred from a high-resolution coral record , 1998 .

[3]  Balaji Rajagopalan,et al.  Analyses of global sea surface temperature 1856–1991 , 1998 .

[4]  M. D. Moore,et al.  Evaluating climate indices and their geochemical proxies measured in corals , 1997, Coral Reefs.

[5]  N. Graham,et al.  Recent changes in tropical freezing heights and the role of sea surface temperature , 1996, Nature.

[6]  R. Reynolds,et al.  Global surface air temperature in 1995: Return to pre‐Pinatubo level , 1996 .

[7]  N. Graham,et al.  Recent Trends in Rain Gauge Precipitation Measurements from the Tropical Pacific: Evidence for an Enhanced Hydrologic Cycle , 1996 .

[8]  Henry F. Diaz,et al.  The Quality Control of Long-Term Climatological Data Using Objective Data Analysis , 1995 .

[9]  T. Coplen,et al.  Reporting of stable hydrogen, carbon, and oxygen isotopic abundances , 1995 .

[10]  P. Jones,et al.  Hemispheric Surface Air Temperature Variations: A Reanalysis and an Update to 1993. , 1994 .

[11]  Thomas M. Smith,et al.  Improved Global Sea Surface Temperature Analyses Using Optimum Interpolation , 1994 .

[12]  Richard G. Fairbanks,et al.  Tropical Temperature Variations Since 20,000 Years Ago: Modulating Interhemispheric Climate Change , 1994, Science.

[13]  B. Tilbrook,et al.  Oceanic Uptake of Fossil Fuel CO2: Carbon-13 Evidence , 1992, Science.

[14]  H. Mächel,et al.  Recent changes of the tropical water and energy budget and of midlatitude circulations , 1990 .

[15]  J. Cole,et al.  The southern oscillation recorded in the δ18O of corals from Tarawa Atoll , 1990 .

[16]  J. Peixoto,et al.  Physics of climate , 1984 .

[17]  R. Dodge,et al.  Annual Periodicity of the 18O16O and 13C12C ratios in the coral Montastrea annularis , 1979 .

[18]  J. Erez.  Vital effect on stable-isotope composition seen in foraminifera and coral skeletons , 1978, Nature.

[19]  R. Buddemeier,et al.  Coral Chronometers: Seasonal Growth Bands in Reef Corals , 1972, Science.

[20]  Samuel Epstein,et al.  REVISED CARBONATE-WATER ISOTOPIC TEMPERATURE SCALE , 1953 .

[21]  H. Urey,et al.  CARBONATE-WATER ISOTOPIC TEMPERATURE SCALE , 1951 .

[22]  J. McCrea.  On the Isotopic Chemistry of Carbonates and a Paleotemperature Scale , 1950 .

[23]  M. Hughes,et al.  Global-scale temperature patterns and climate forcing over the past six centuries , 1998 .

[24]  T. McConnaughey.  13C and 18O isotopic disequilibrium in biological carbonates: II. In vitro simulation of kinetic isotope effects , 1989 .

[25]  T. McConnaughey.  13C and 18O isotopic disequilibrium in biological carbonates: I. Patterns , 1989 .

[26]  P. Swart.  Carbon and oxygen isotope fractionation in scleractinian corals: a review , 1983 .

[27]  J. N. Weber,et al.  Carbon and oxygen isotope fractionation in the skeletal carbonate of reef-building corals , 1970 .

[28]  H. Urey,et al.  The thermodynamic properties of isotopic substances. , 1947, Journal of the Chemical Society.