Long-term monitoring of sea temperature on the Great Barrier Reef (C3.1.1)

Task leader: Dr Ray Berkelmans, Australian Institute of Marine Science.

Task associate: Ms Simona Trimarchi, Ports Corporation of Queensland.

CRC Reef has supported a project by Ray Berkelmans (from Australian Institute of Marine Science, formerly from Great Barrier Reef Marine Park Authority - GBRMPA) to install and monitor a sea temperature monitoring system. The monitoring program commenced in 1996 and aimed to build a picture of sea temperature trends at various locations throughout the Great Barrier Reef. Initially, 80 data loggers were deployed at 40 representative sites. Additional sites were added at several Queensland ports over time. The data loggers are downloaded every six to 12 months, and summaries are available on GBRMPA's website. Research organisations can download the data for global climate research. The sea temperature monitoring program captured comprehensive data during the 1998 bleaching event which may enable an early warning system to be developed for any future bleaching events.

GBRMPA water temperature site

CRC Reef researchers working at the Australian Institute of Marine Science (AIMS) have also established two automatic reef-based weather stations and software in collaboration with the US-based National Oceanographic and Atmospheric Administration (NOAA) to help provide early warnings of temperature anomalies.

Research at AIMS supported by CRC Reef on global climate change and coral bleaching has linked the 1998 warming event to an unusually strong El Nino-Southern Oscillation (ENSO) event, with possible enhancement by global warming. Satellite technology is also being used in the study- to map spatial and temporal patterns in sea temperature with a view to scenario modelling and risk assessment of future episodes of coral bleaching and death.

Research into environmental records contained in coral skeletons suggests that so far there has been no impact on the fundamental process of coral calcification. To 1980, calcification rates had increased with increasing average sea temperatures, more than counteracting any declines caused by changing ocean chemistry brought about by rising carbon dioxide levels in the atmosphere. Analysis of more recent coral growth will determine whether this trend has continued to the end of the century.

For more information see CRC Reef Publications on coral bleaching and climate change