Last summer, the Great Barrier Reef experienced its worst-ever coral bleaching event – data has shown it was even the more severe than in 1998.
Despite this, many sections of the Reef are showing signs of recovery. UQ’s Director of the Centre for Marine Studies, Professor Ove Hoegh-Guldberg, is examining reasons why parts of the reef are doing better than expected.
The future of the Great Barrier Reef
University of Queensland researchers are reporting that sections of the Great Barrier Reef severely bleached last summer are showing surprising signs of recovery.
Although there are still some dead patches on the reef, there hasn’t been the destruction of whole colonies, as was the case during the last major bleaching event in 1998.
This is surprising, because this year’s coral bleaching event on the Great Barrier Reef was its worst-ever. The Great Barrier Reef Marine Park Authority (GBRMPA) aerial surveys found coral-bleaching was evident at almost 60 percent of the 641 reefs surveyed.
Professor Hoegh-Guldberg doesn’t agree with the theory that coral is somehow adapting to climate change. He believes the explanation for the differences between 1998 and 2002 may be the severity of the following winter.
Unlike 1998, the 2002 bleaching event, although severe, was followed by a relatively warm winter. Further research is continuing into how coral can recover from bleaching.
Professor Hoegh-Guldberg however believes that the better-than-expected recovery of the coral affords no room for complacency. Should future warm-water events increase in severity, duration, or frequency, coral-bleaching on the Great Barrier Reef is likely to become increasingly severe .
Professor Hoegh-Guldberg has been issuing dire warnings about the future of the Reef since 1999. He has warned that if severe bleaching events continue, the Great Barrier Reef may be largely coral-free within 50 to 100 years.
He argues the reef-building corals that make the Reef possible are likely to become very rare if global warming continues unabated. Corals do not survive the tropical sea temperatures predicted by 99 percent of all global climate experts.
Using results of climate-modeling by various international research organisations and knowledge of the maximum temperatures coral can withstand, the predictions point to some reefs suffering major damage in as few as 20 years from now with most coral reefs unable to survive the Century.
Taking into account various environmental fluctuations such as the El Nino and La Nina cycles, ocean temperatures have been rising 1–2 degrees Celsius per century and the capacity for corals to adapt to the rising temperatures has already been exceeded during the warmest years.
The latest Intergovernmental Panel on Climate Change (IPCC) report has projected warming of between 2–6 degrees Celsius by the end of this Century.
The temperature rise is primarily due to atmospheric carbon dioxide and chlorofluorocarbons (CFCs). Even pristine reefs in isolated locations far from direct human influence are suffering damage due to changes in the atmosphere.
Professor Hoegh-Guldberg stresses the importance of a global approach including commitments from governments and international organisations.
The University of Queensland is a lead partner in a major funding proposal to the Global Environmental Facility, which will involve more than 20 countries in targeted research across the issue of climate change and coral reefs.
Media: For more information, contact Professor Ove Hoegh-Guldberg (telephone 07 3365 1156 or 3365 4333) or Jan King at UQ Communications (telephone 07 3365 1120 or mobile 0413 601 248).
