Corrosive Oceans: Carbon Emissions Threaten Ecosystem

Rising Co2 levels in oceans pose threat to ecosystem, sea life worldwide.

ByABC News
August 21, 2008, 12:32 PM

Aug. 22, 2008— -- Under the vast, trackless surface of the ocean, scientists have discovered a monster of a problem, literally rising from the deep.

The world's oceans are becoming more acidic and corrosive because of the same carbon emissions that cause another immense problem: global warming.

"We think this can have devastating impacts on our ocean ecosystem," said Richard Feely, program manager at the National Oceanic and Atmospheric Association's Pacific Marine Environmental Laboratory.

Cold water naturally absorbs carbon dioxide from the air, and the oceans have absorbed about half of the carbon emissions we've spewed out in the last two centuries -- hundreds of billions of tons of it.

Scientists first thought that was a good thing, since all that carbon sinking into the ocean meant it wouldn't be causing even more global warming in the air.

But Feely says that "the ocean ecosystem can no longer handle all this excess Co2."

The problem? Excess carbon dioxide turns seawater into carbonic acid. Scientists report the ocean's new acidity worldwide is crippling sea creatures in their efforts to form their shells and skeletons, to breathe, to move and catch prey, and to reproduce and mature.

Scientists have been slow to identify the problem, partly because it's invisible. Life in the ocean is mostly out of sight and out of mind, down there under that vast gray surface. Also invisible is all the carbon dioxide and its absorption into the ocean surface. But now scientists are beginning to see it all.

Huge amounts of fossil fuels have been burned since the industrial age began, and those carbon emissions have already increased the ocean's acidification by 30 percent. This summer scientists were stunned to find acidic waters -- normally trapped in the deeper parts of the ocean -- rising up to shallow waters just off shore on the continental shelf, where so much sea life is found.

"This corrosive ocean acidified water has come on to our continental shelf years 50 to 100 years before we ever thought it would be occurring," Feely said.