Acidification Sign Shows Up On Great Barrier Reef - Calcification Rate Down 21% In 16 Years

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Scientists studying Australia’s Great Barrier Reef may have detected the first signs of impact of ocean acidification after finding a sharp cut in growth rates in some corals. Oceans become acidic when carbon dioxide (CO2) emitted by humanity dissolves in sea water. This increase in acidity makes it harder for marine organisms to grow and maintain their shells.

The researchers studied a common coral species called porites, growing along the northern end of the Great Barrier Reef off Queensland. The species grows into massive reefs and is a key species for reef eco-systems around the world.

The scientists found that calcification - the process by which corals extract calcium carbonate from seawater to build their protective shells - had slowed by 21% over the past 16 years. Timothy Cooper, a scientist at the Australian Institute of Marine Sciences, said the findings were “consistent” with the impact of raised CO2 levels and raised temperatures, both of which are linked to global climate change.

However, the study, just published in Global Change Biology, also warns that further research was needed to confirm the link.

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http://www.timesonline.co.uk/tol/news/uk/science/article3423465.ece