Monday, September 16, 2013

Ocean acidification having same impact on oceans that climate change is having on land

About 25 percent of all carbon dioxide emitted through burning fossil fuels, such as coal, oil and natural gas, gets absorbed by the seas, equaling about 20 trillion pounds each year, Craig Welch reports for The Seattle Times.  "All that CO2 is changing the chemistry of the ocean faster than at any time in human history. Now the phenomenon known as ocean acidification — the lesser-known twin of climate change — is helping push the seas toward a great unraveling that threatens to scramble marine life on a scale almost too big to fathom, and far faster than first expected." (Top photo shows a healthy coral reef; below is an unhealthy reef affected by excess carbon dioxide)

"When CO2 mixes with water it takes on a corrosive power that erodes some animals’ shells or skeletons. It lowers the pH, making oceans more acidic and sour, and robs the water of ingredients animals use to grow shells in the first place," Welch writes. The result of "changing sea chemistry already has killed billions of oysters along the Washington coast and at a hatchery that draws water from Hood Canal. It’s helping destroy mussels on some Northwest shores. It is a suspect in the softening of clam shells and in the death of baby scallops. It is dissolving a tiny plankton species eaten by many ocean creatures, from auklets and puffins to fish and whale."

"Ocean acidification also can bedevil fish and the animals that eat them, including sharks, whales, seabirds and, of course, bigger fish. Shifting sea chemistry can cripple the reefs where fish live, rewire fish brains and attack what fish eat," Welch writes. "Those changes pose risks for our food, too. Globally, overfishing remains a scourge. But souring seas and ocean warming are expected to reduce even more of the plants and animals we depend on for food and income. The changes will increase ocean pests, such as jellyfish, and make the system more vulnerable to disasters and disease. The transformation will be well under way by the time today’s preschoolers reach middle age."

Stephen Palumbi, a professor of evolutionary and marine biology at Stanford University, told Welch, There’s a train wreck coming and we are in a position to slow that down and make it not so bad. But if we don’t start now the wreck will be enormous.” But not much is being done about the problem. "Combined nationwide spending on acidification research for eight federal agencies, including grants to university scientists by the National Science Foundation, totals about $30 million a year — less than the annual budget for the coastal Washington city of Hoquiam, population 10,000," Welch writes. (Read more)

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