Alaska's cold waters make the region more prone to ocean acidity caused by fossil fuel emissions. (Photo: Stock File)

Alaska fisheries at risk from pollutants

UNITED STATES
Wednesday, November 04, 2009, 21:50 (GMT + 9)

Fish and shellfish populating US waters are set to receive more protection from mercury and other toxins in the atmosphere

The Environmental Protection Agency (EPA) announced last week that it is forcibly reducing fossil fuel emissions from US power plants, SitNews reports. The decision -- the first of its kind ever taken -- will have positive implications for oceans.

About half of the carbon dioxide produced by burning fossil fuels is absorbed by the seas and heightens water acidity.

Many other polluters were obliged to reduce toxic emissions when the Clean Air Act was strengthened in 1990. However, the Bush Administration issued a ruling that absolved US power plants, the largest source of carbon dioxide and mercury pollution, from complying with EPA regulations.

In February 2008, a federal appeals court overturned that ruling and ordered the EPA to regulate toxic air pollutants from power plants.

By November 2011, the EPA will be required to establish controls for coal- and oil-fired power plants; oil generates only a small percentage of electricity in the United States.

Firms will have three years to comply after the new regulations go into effect.

A large percentage of the atmospheric pollutants in the North Pacific are sourced from coal fired power plants in Asia. According to scientists, water samples collected last spring from the Gulf of Alaska showed that acid levels are increasing more quickly and severely than had been thought before.

The Gulf study yielded similar results to tests undertaken in the Chukchi and Bering Seas.

"It seems to be more accelerated in Alaska because of the colder water temperatures. Cold water naturally holds more carbon dioxide (CO2), which controls the acidity levels in the water," said Jeremy Mathis, a chemical oceanographer at the University of Alaska/Fairbanks.

The increase in acidity adversely affects calcium carbonate, the main component of sea creatures' skeletons and shells. Scientists estimate the ocean is 25 per cent more acidic now than it was 300 years ago.

"This isn't the case where we're going to talk about the impact 100 years from now," Mathis said. "This is an impact that we're going to see over the next decade that could potentially disrupt all the major fisheries in Alaska."

Related article:

- Oceans growing dangerously more acidic, say scientists

By Denise Recalde
editorial@fis.com
www.fis.com