Rising CO2 levels may reduce coral reefs’ ability to fight climate change
Washington, Oct 29 : A major new investigation by Australian scientists has revealed that rising carbon dioxide levels in the world’s oceans could deliver a disastrous blow to the ability of coral reefs to withstand climate change.
The investigation has revealed that acidification of the oceans from human CO2 emissions has the potential to worsen the impact of the bleaching and death of reef-building organisms expected to occur under global warming.
The study, by a team led by Dr Ken Anthony of the ARC Centre of Excellence for Coral Reef Studies and the University of Queensland, concludes that earlier research may significantly understate the likely damage to the world’s reefs caused by man-made change to the Earth’s atmosphere.
In a large experiment on Australia’s Heron Island, the team simulated CO2 and temperature conditions predicted for the middle and end of this century, based on current forecasts of the world’s likely emission levels and warming by the Intergovernmental Panel on Climate Change (IPCC).
The results of their analyses of the bleaching, growth and survival of a number of organisms including corals indicates that a number of very important reef builders may be completely lost in near future.
“We found that coralline algae, which glue the reef together and help coral larvae settle successfully, were highly sensitive to increased CO2. These may die on reefs such as those in the southern Great Barrier Reef (GBR) before year 2050,” said Dr Anthony.
The CoECRS team erected 30 large aquaria in the waters of Heron Island in the southern GBR and studied the combined effects of warming, high CO2 and sunlight on a large range of reef organisms for eight weeks.
“The results, frankly, are alarming,” said Professor Ove Hoegh-Guldberg. “They clearly suggest that previous predictions of coral bleaching have been far too conservative, because they didn’t factor in the effect of acidification on the bleaching process and how the two interact,” he added.
The results of the team’s analyses of the bleaching, growth and survival of key coral reef species indicate that a number of very important reef builders may be completely lost in the near future.
According to Dr Guillermo Diaz-Pulido, “This is an important discovery that can buy the reef time while the nations of the world work together to stabilize CO2 emissions.”
The results of the research are being offered to reef managers to help them develop strategies to protect the reefs that are most at risk. (ANI)