A 200-year coral stable oxygen isotope record from a high-latitude reef off Western Australia

• Published in: Coral reefs 1999-04, Vol.18 (1), p.1-12
• Main Authors: KUHNERT, H, PÄTZOLD, J, HATCHER, B, WYRWOLL, K.-H, EISENHAUER, A, COLLINS, L. B, ZHU, Z. R, WEFER, G
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Marine; Porites lutea; Scleractinia; Sea water ecosystems; Synecology
• ISSN: 0722-4028; 1432-0975
• DOI: 10.1007/s003380050147

A core from a coral colony of Porites lutea was analysed for stable oxygen isotopic composition. A 200-year proxy record of sea surface temperatures from the Houtman Abrolhos Islands off west Australia was obtained from coral delta super(18)O. At 29 degree S, the Houtman Abrolhos are the southernmost major reef complex of the Indian Ocean. They are located on the path of the Leeuwin Current, a southward flow of warm, tropical water, which is coupled to Indonesian throughflow. Coral delta super(18)O primarily reflects local oceanographic and climatic variability, which is largely determined by spatial variability of the Leeuwin Current. However, coherence between coral delta super(18)O and the current strength itself is relatively weak. Evolutionary spectral and singular spectrum analyses of coral delta super(18)O demonstrate a high variability in spectral composition through time. Oscillations in the 5-7-y, 14-15-y, and quasi-biennial bands reflect teleconnections of local sea surface temperature (SST) to Tropical Pacific climate variability. Deviations between local (coral-based) and regional (instrument) SST contain a cyclic component with a period of 15 y. Coral delta super(18)O suggests a rise in SST by 0.6'C since AD 1944, consistent with available instrumental SST records. A long-term warming by 1.4 degree C since AD 1795 is inferred from the coral record.