Several times over the past months we’ve noted the anticipated effects of ocean acidification. As the atmosphere’s carbon dioxide content increases, some of it mixes with ocean water, forming carbonic acid, lowering the pH of ocean water. Even a slightly more acidic ocean could be enormously damaging to sea creatures, because it also means less of the mineral aragonite that some sea creatures use to form their shells.

We just didn’t really expect it would happen this fast. From New Scientist:

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In a small patch of the Southern Ocean, the shells of sea snails are dissolving. The finding is the first evidence that marine life is already suffering as a result of man-made ocean acidification.

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“This is actually happening now,” says Geraint Tarling of the British Antarctic Survey in Cambridge, UK. He and colleagues captured free-swimming sea snails called pteropods from the Southern Ocean in early 2008 and found under an electron microscope that the outer layers of their hard shells bore signs of unusual corrosion. …

He visited the Southern Ocean near South Georgia where deep water wells up to the surface. This water is naturally low in aragonite, meaning the surface waters it supplies are naturally somewhat low in the mineral — although not so much so that it would normally be a problem. Add in the effect of ocean acidification, however, and Tarling found that the mineral was dangerously sparse at the surface.

“It’s of concern that they can see it today,” says Toby Tyrrell of the National Oceanography Centre in Southampton, UK.

The state of the world: It is of concern that a terrible thing we expected in the future can be seen today.

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How do we save these sea creatures? The way we save ourselves.

The only way to stop ocean acidification is to reduce our CO2 emissions, Tyrrell says. It has been suggested that we could add megatonnes of lime to the ocean to balance the extra acidity. However, Tyrrell says this is “probably not practical” because the amounts involved — and thus the costs — are enormous.

If only there were some animal on Earth that we felt was worth such an expenditure.