Alaskan Seas Hit Hard By Acidification - In Some Areas, Pteropods Already Unable To Form Shells

The Arctic's increased vulnerability to climate change is not limited to higher temperatures and melting permafrost.

New research from the University of Alaska Fairbanks suggests Arctic oceans are particularly susceptible to acidification, with potentially dire consequences to Alaska's rich crab and salmon fisheries.

"Everything is acting in unison on the environment – it's not just the ice loss or the warming or the acidification," said UAF chemical oceanographer Jeremy Mathis. "The Arctic is taking a multilateral hit." Mathis' newest data from the Gulf of Alaska show that acidity levels far higher than expected might already be impacting the food web. In several sites the increasing acidity has changed ocean chemistry so significantly that organisms are unable to pull crucial minerals out of the water to build shells, he said.

EDIT

But the impact is already being felt by a tiny creature at the base of the food web supporting the state's legendary salmon runs – the pteropod, or swimming sea snailPteropod-300. Accounting for up to half the diet of pink salmon, pteropods build shells from a form of calcium, aragonite, most vulnerable to acidification. Mathis' sampling of the Gulf of Alaska found several spots so undersaturated with aragonite that pteropods would find it impossible to create a shell. Scientists estimate a 10 percent drop in the pteropod populations could drop the body weight of salmon by 20 percent; Mathis, talking with commercial salmon fishers in Alaska's Kenai Peninsula earlier this year, said many have reported smaller than normal fish.

EDIT

http://wwwp.dailyclimate.org/tdc-newsroom/2009/08/rising-acidity-erodes-alaskas-fisheries

Excuse me.
As you were.

n/t

Some are reporting a complete fisheries' collapse, even after a three year moratorium on fishing.

On a bright note, the oceans will be far less acidic after the ice caps have melted - until they've absorbed the remaining CO2 from the atmosphere, anyway.