Antarctic Animals Are Dissolving

Scientists have warned about ocean acidification for years, but now it’s actually happening

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British Antarctic Survey, Nina Bednarsek

Scientists have warned about ocean acidification in the future. As the oceans absorbe more anthropogenic carbon dioxide, the pH of the water decreases and can cause untold damage to marine animals. Now, it’s actually happening. In a small patch in the Southern Ocean, near South Georgia Island, sea snail shells are dissolving thanks to man-made acidification. New Scientist reports:

“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.

The ocean’s pH is currently dropping around 0.1 per century, shirting faster than at any time within the last 300 million years. This scenario spells disaster for animals with hard shells such as corals and mollusks, since excess carbonic acid (dissolved CO2) impacts the availability of the calcium carbonate that the organisms depend upon for building their shells.

By 2050, regions lacking in shell-supporting nutrients will become widespread, according to predictive climate models. The polar oceans will be the first to succumb to this problem, followed by the tropics a few decades later. The researchers told New Scientist, ”These pockets will start to get larger and larger until they meet.”

As with most aspects of climate change, the only way to slow or stop this process is to reduce our carbon dioxide emissions.

More from Smithsonian.com:

Ocean Acidification and the Battle Between Seaweed and Coral
Will the Oyster Survive Ocean Acidification? Depends on the Oyster

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