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Group warns of shift in oceans' pH

WASHINGTON - With the oceans absorbing more than 1 million tons of carbon dioxide an hour, a National Research Council study released Thursday found acid in the oceans is increasing at an unprecedented rate and threatening to change marine ecosystems.

The council said the oceans are 30 percent more acidic than before the start of the Industrial Revolution roughly 200 years ago, and one-third of today’s carbon dioxide emissions are absorbed by the oceans.

Unless emissions are reined in, ocean acidity could increase by 200 percent by the end of the century and even more in the next century, said James Barry, a senior scientist at the Monterey Bay Aquarium Research Institute in California and one of the study’s authors.

“Ocean acidification is changing the chemistry of the oceans at a scale and magnitude greater than thought to occur on earth for many millions of years and is expected to cause changes in the growth and survival of a wide variety of marine organisms, potentially leading to massive shifts in ocean ecosystems,” Barry told the Senate Commerce Committee’s oceans, atmosphere, fisheries and Coast Guard subcommittee.

Also testifying was actress Sigourney Weaver, who made passing references to her roles in “Alien” and “Avatar” while urging Congress to pass global climate change legislation.

The hearing came on the 40th observance of Earth Day, an anniversary noted by the subcommittee’s chairwoman, Sen. Maria Cantwell, D-Wash.

“We know that this is changing the very chemistry of our oceans,” Cantwell said. “And while the full implications of these changes aren’t clear, the initial signs are frightening.”

The effects of growing ocean acid levels might be more pronounced off the Northwest coast. Cold water absorbs more carbon dioxide than warm water. And a phenomenon known as “upwelling” off the coast of Washington state and Oregon brings deep ocean water already more acidic to the surface, where it is saturated with even more carbon dioxide. According to one study, upwelling of acidified water off the West Coast had reached levels not anticipated until 2050.

Shellfish growers and commercial fishermen from the Gulf of Alaska to the Gulf of Mexico are worried.

“This is a devastating ghost lurking in the shadows that would change our whole lives,” said Donald Waters, a commercial fisherman who fishes for red snapper and king mackerel out of Pensacola, Fla.

The National Research Council report, requested by Congress, said carbon dioxide emissions are increasing so rapidly that natural processes in the sea that maintain pH levels can’t keep up. The pH scale measures acid or alkaline levels, with 7 being neutral. The average pH of ocean surface waters has decreased from 8.2 to 8.1 and while that not might seem a lot, scientists are concerned.

Not everyone is convinced rising acid levels would be devastating.

John Everett, a former scientist with the National Oceanic and Atmospheric Administration who is now a consultant on ocean issues, told the subcommittee the oceans will remain alkaline even as they absorb more carbon dioxide.

Everett said rainwater, which absorbs carbon dioxide as it is falling, is 100 times more acidic than ocean water. He also assured beachgoers that their feet will not dissolve when they enter the water. “It doesn’t look like it is a problem,” said Everett. “I don’t see damage.”

Les Blumenthal: 202-383-0008

lblumenthal@mcclatchydc.com

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