As politicians debate the merits of a carbon tax scheme, antarctic waters are being used to create an early warning system for oceans affected by climate change.
Carbon dioxide does not just affect global warming. Ocean acidification is picking up pace, threatening entire marine ecosystems.
Famed coral, like the Great Barrier Reef, is at risk from more acidic seawater, but the planet’s polar waters are especially vulnerable.
Aboard the temporary floating science laboratory Aurora Australis, marine geologist Dr Will Howard and a team of scientists are investigating the marine repercussions of climate change by sampling the curious life of the southern ocean.
Rarely seen, tiny marine snails called pteropods are vulnerable to subtle changes in ocean chemistry.
The concern is that if seawater becomes too acidic they and other organisms like coral will not be able to form.
Dr Howard says entire ecosystems are at risk.
“The raw ingredient that a lot of these shell making organisms require is being reduced,” he said.
“Now some of the evidence we are getting from the field would suggest that they are sensitive enough to already be feeling the impact of that reduction in this raw material they need for their shells.”
Dr Howard says seawater is slightly alkaline, but increasing carbon dioxide is making the ocean more acidic.
“It is unprecedented for millions of years the last time the carbon dioxide of the atmosphere was as high as we have now,” he said.
Dr Howard says the acidity of the oceans has increased by about 30 per cent.
“That acid in this case has been added by additional carbon dioxide because unlike other gases, when it dissolves in water it forms a weak carbonic acid and that is the source of acidification, and that is the source of the concern,” he said.
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Karen Barlow, ABC News, 3 March 2011. Full article.
