TY - JOUR
T1 - Eastern Pacific sea surface temperature since 1600 A.D.
T2 - The δ18O record of climate variability in Galápagos Corals
AU - Dunbar, Robert B.
AU - Wellington, Gerard M.
AU - Colgan, Mitchell W.
AU - Glynn, Peter W.
PY - 1994/4
Y1 - 1994/4
N2 - We measured stable oxygen isotope ratios and skeletal growth rates in the massive corals Pavona clavus and P. gigantea from the west coast of Isabela Island, Galapagos, to assess interannual to decadal climate variability in the eastern Pacific. Comparisons of instrumental data sets show that sea surface temperatures (SST) in the Galapagos region are representative of a broad portion of the eastern equatorial Pacific. The P. gigantea isotope record is nearly monthly in resolution, spans the period 1961-1982, and shows strong correlation with a Galapagos instrumental SST record. Cross-spectral analysis shows that SST can explain greater than 80% of the variance in δ18O at both the annual cycle and within the high-frequency portion of the ENSO band (3-5 years). The P. clavus record is annual in resolution, extends from 1587 to 1953 A.D., and was obtained from a 10-m diameter colony preserved within the Urvina Bay uplift. The isotopic record appears to be a very good, but not perfect, indicator of ENSO events. The dominant oscillatory modes, both within the ENSO and interdecadal frequency bands, shift to shorter periods from the early to middle 1700s and again from the middle to late 1800s. This may reflect major reorganizations within the tropical ocean-atmosphere system and suggests that tropical Pacific climate variability is linked across timescales ranging from years to decades. -from Authors
AB - We measured stable oxygen isotope ratios and skeletal growth rates in the massive corals Pavona clavus and P. gigantea from the west coast of Isabela Island, Galapagos, to assess interannual to decadal climate variability in the eastern Pacific. Comparisons of instrumental data sets show that sea surface temperatures (SST) in the Galapagos region are representative of a broad portion of the eastern equatorial Pacific. The P. gigantea isotope record is nearly monthly in resolution, spans the period 1961-1982, and shows strong correlation with a Galapagos instrumental SST record. Cross-spectral analysis shows that SST can explain greater than 80% of the variance in δ18O at both the annual cycle and within the high-frequency portion of the ENSO band (3-5 years). The P. clavus record is annual in resolution, extends from 1587 to 1953 A.D., and was obtained from a 10-m diameter colony preserved within the Urvina Bay uplift. The isotopic record appears to be a very good, but not perfect, indicator of ENSO events. The dominant oscillatory modes, both within the ENSO and interdecadal frequency bands, shift to shorter periods from the early to middle 1700s and again from the middle to late 1800s. This may reflect major reorganizations within the tropical ocean-atmosphere system and suggests that tropical Pacific climate variability is linked across timescales ranging from years to decades. -from Authors
UR - http://www.scopus.com/inward/record.url?scp=0028322790&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028322790&partnerID=8YFLogxK
U2 - 10.1029/93PA03501
DO - 10.1029/93PA03501
M3 - Article
AN - SCOPUS:0028322790
VL - 9
SP - 291
EP - 315
JO - Paleoceanography and Paleoclimatology
JF - Paleoceanography and Paleoclimatology
SN - 2572-4517
IS - 2
ER -