Ocean Acidification Update

Oceans' Growing Acidity Alarms Scientists
By Les Blumenthal
McClatchy Newspapers

Sunday 16 December 2007

Washington - Seven hundred miles west of Seattle in the Pacific at Ocean Station Papa, a first-of-its-kind buoy is anchored to monitor a looming environmental catastrophe.

Forget about sea levels rising as glaciers and polar ice melt, and increasing water temperatures affecting global weather patterns. As the oceans absorb more and more carbon dioxide and other greenhouse gases, they're gradually becoming more acidic.

And some scientists fear that the change may be irreversible.

At risk are sea creatures up and down the food chain, from the tiniest phytoplankton and zooplankton to whales, from squid to salmon to crabs, coral, oysters and clams.

The oceans are already 30 percent more acidic than they were at the beginning of the Industrial Revolution, as they absorb 22 tons of carbon dioxide a day. By the end of the century, they could be 150 percent more acidic.

"Everything points to dramatic effects," said Richard Feely, an oceanographer with the National Oceanic and Atmospheric Administration in Seattle. "There are suggestions the entire ecosystem could change over time."

Originally, scientists thought the oceans could be one of the solutions to the buildup of greenhouse gases, as they absorb about one-third of the carbon dioxide that's emitted worldwide. But they now know that the fundamental chemistry of the oceans has changed, and the possible impacts seem to grow more nightmarish as research accelerates.

"It seems like it is a one-way street, and that is alarming," said Steven Emerson, a professor of oceanography at the University of Washington. "The pH of the oceans could be lowered permanently."

[. . .]

Though cuts in carbon dioxide and other greenhouse-gas emissions might slow or reverse global warming, scientist say it could take thousands of years or longer to reverse the increased acidity of the oceans.

"For all practical purposes this is permanent," Emerson said. "That's not true of temperature. But with ocean acidification the time scales are long."

H2O + CO2 = H2CO3

That means water plus carbon dioxide equals carbonic acid, which disolves sea shells and coral.

the Independent:

A world dying, but can we unite to save it?

Pollution in the seas is now speeding global warming, says a devastating new climate report.

'IoS' Environment Editor Geoffrey Lean reports from Valencia

Published: 18 November 2007

Humanity is rapidly turning the seas acid through the same pollution that causes global warming, the world's governments and top scientists agreed yesterday. The process – thought to be the most profound change in the chemistry of the oceans for 20 million years – is expected both to disrupt the entire web of life of the oceans and to make climate change worse.

The warning is just one of a whole series of alarming conclusions in a new report published by the official Intergovernmental Panel on Climate Change (IPCC), which last month shared the Nobel Peace Prize with former US vice president Al Gore.

[. . .]

Scientists have found that the seas have already absorbed about half of all the carbon dioxide emitted by humanity since the start of the industrial revolution, a staggering 500 billion tons of it. This has so far helped slow global warming – which would have accelerated even faster if all this pollution had stayed in the atmosphere, already causing catastrophe – but at an increasingly severe cost.

The gas dissolves in the oceans to make dilute carbonic acid, which is increasingly souring the naturally alkali seawater. This, in turn, mops up calcium carbonate, a substance normally plentiful in the seas, which corals use to build their reefs, and marine creatures use to make the protective shells they need to survive. These include many of the plankton that form the base of the food chain on which all fish and other marine animals depend.

As the waters are growing more acid this process is decreasing, with incalculable consequences for the life of the seas, and for the fisheries on which a billion of the world's people depend for protein. Every single species that uses calcium in this way, that has so far been studied, has been found to be affected. And the seas are most acid near the surface, where most of their life is concentrated.

A report by the Royal Society, Britain's premier scientific body, concludes that, as a result, of the pollution, the world's oceans are probably now more acidic that they have ever been in "hundreds of millennia", and that even if emissions stopped now, the waters would take "tens of thousands of years to return to normal".

Professor Ulf Reibesell of the Leibnitz Institute of Marine Sciences in Kiel, Germany's leading expert on the process, concludes in an issue of UNEP's magazine Our Planet, to be published next month, that, if it continues to the levels predicted by yesterday's report for the end of the century, the seas will reach a condition unprecedented in the last 20 million years.