Steve Connor | May 23

The Independent - A significant increase in the acidity of the Pacific Ocean has been detected by scientists, who believe it could upset the delicate balance of marine ecosystems and lead to their collapse.

Rising ocean acidity is one of the results of increasing levels of carbon dioxide in the atmosphere and scientists are concerned that the phenomenon could make it impossible for key species in the marine food chain to make their protective shells.

The scientists, led by Richard Feely of the US National Oceanic and Atmospheric Administration (NOAA), surveyed 13 different locations off the west coast of North America, from Canada to Mexico, and found higher-than-expected levels of acidity in seawater samples taken near the surface.

"Our results show for the first time that a large section of the North American continental shelf is impacted by ocean acidification," the scientists said in their study, published online in the journal Science.

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"This phenomenon, which is commonly called 'ocean acidification', could affect some of the most fundamental biological and geochemical processes of the sea in the coming decades, and could seriously alter the fundamental structure of pelagic [free- swimming] and benthic [seafloor] ecosystems," the scientists said.

Dr Feely said many species of fish that are not directly affected by rising acidity levels would nevertheless still be indirectly affected by the inability of key marine organisms to make their protective shells. "The best example, of course, is coral reefs. They support 25 per cent of the entire biodiversity of the world's oceans. If they should be lost, then many of the fish species that depend on them would also be lost," Dr Feely said.

"Coral reefs also provide food resources for 500 million people throughout the world. Deep- water corals have been found along the US coast, from California to Alaska," he said.

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Sealife at risk from rapid acidification

· Increased CO2 levels to blame, say experts
· Catastrophic impact on marine ecology predicted

The Guardian, By James Randerson, May 23

Scientists conducting a major survey of the North American Pacific coast have found significant increases in acidity that could have a profound effect on sealife.

Rising ocean acidity has been predicted by scientists as a consequence of increased CO2 emissions, but the new research suggests that in some parts of the ocean these increases are happening much faster than predicted. The change seen in the surveys was not expected until 2050.

Experts predict that the changes could have a catastrophic effect on marine life. More acidic seawater means that species such as shellfish, plankton and coral will have much more difficulty making their shells and hard skeletons. That will seriously reduce the productivity of the entire food chain, changing ocean ecology and leading potentially to drastic reductions in fish stocks.

"It's very worrying," said Dr Carol Turley, at Plymouth Marine Laboratory. "The marine food web is extremely complex so [the effects are] very hard to predict. Whether it will support the kind of food web we are used to seeing and depending on in future is anyone's guess really."

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Acidified ocean water rising up nearly 100 years earlier than scientists predicted

The Seattle Times, By Sandi Doughton, May 23

Climate models predicted it wouldn't happen until the end of the century.

So Seattle researchers were stunned to discover that vast swaths of acidified sea water are already showing up along the Pacific Coast as carbon dioxide from power plants, cars and factories mixes into the ocean.

In surveys from Vancouver Island to the tip of Baja California, the scientists found the first evidence that large amounts of corrosive water are reaching the continental shelf — the shallow sea margin where most marine creatures live. In some places, including Northern California, the acidified water was as little as four miles from shore.

"What we found ... was truly astonishing," said oceanographer Richard Feely, of the National Oceanic and Atmospheric Administration's Pacific Marine Environmental Laboratory in Seattle. "This means ocean acidification may be seriously impacting marine life on the continental shelf right now."

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Until now, researchers believed most of the acidified water was confined to the deep oceans.

But during ship-based surveys last year, Feely and his colleagues found the natural upwelling that occurs along the West Coast each spring was pulling the acidified water up onto the continental shelf.

"This is another example where what's happening in the natural world seems to be happening much faster than what our climate models predict," said Carnegie Institution climate scientist Ken Caldeira, whose work suggested it would be nearly 100 years before acidified water was common along the West Coast.

And there's worse to come, the scientists warn.

The acidified water upwelling along the coast today was last exposed to the atmosphere about 50 years ago, when carbon-dioxide levels were much lower than they are now. That means the water that will rise from the depths over the coming decades will have absorbed more carbon dioxide, and will be even more acidic.