Chronological control of coral records using luminescent lines and evidence for non-stationary ENSO teleconnections in northeast Australia

Abstract

Eight, multicentury, Porites coral cores were used to develop a 373-year chronology by cross-dating techniques adapted from dendrochronology. Characteristic patterns of distinct luminescent lines within the coral skeletons were matched between coral cores from inshore and mid-shelf reefs in the central Great Barrier Reef, Australia. Skeleton-plots of luminescent banding were produced for each core and combined into a master chronology back to AD 1615. In addition to improving dating control, the luminescence master chronology provides a proxy for Burdekin River runoff and Queensland summer rainfall. Variations in the magnitude of the correlation between the luminescence master and the Mann et al. (2000) NINO3 sea-surface temperature reconstruction provides insights into the long-term stability of El Niño-Southern Oscillation (ENSO) teleconnections. Burdekin River runoff was significantly inversely related to ENSO variability for much of the period from the AD 1650s to 1800, suggesting that ENSO-related teleconnections were as dominant then as in recent decades. The extremely dry mid-1760s to mid-1780s stand out as a period of anomalously positive correlation between river runoff and the NINO3 reconstruction. Weak ENSO teleconnections are apparent from the 1800s to 1870s, when conditions were possibly similar to those reported for the 1920s-1950s.