Tuesday, April 17, 2012

Conversations about Washington's future — helping Washington respond to the growing threat of ocean acidification

By Ted Sturdevant, Ecology Director

In the past several years, Washington's shellfish producers have seen significant increases in oyster larvae deaths. Some species aren't able to build their shells. Others species survive long enough to form shells, but they never reach market size.

What is going on?

A mounting body of evidence suggests that the ocean's chemistry is changing, due to increased carbon dioxide from emissions, polluted land runoff and other sources.

The ocean absorbs about one-third of the carbon dioxide released in the atmosphere. As this happens, a chemical reaction takes place that lowers the pH of the water and makes it more acidic. Acids tend to dissolve calcium compounds. And because of that, ocean acidification interferes with the ability of certain organisms - like Pacific oysters - to build their shells.

Washington's shellfish industry employs thousands of people and contributes hundreds of millions of dollars to the state economy - so this is an economic as well as an environmental threat.

There is an even larger concern. Some of the ocean's smallest creatures that use some form of calcium for their shells are essential links in the food chain. Directly or indirectly, they supply food for larger species such as salmon, halibut, cod and whales.

While the growing acidity of our oceans is a worldwide problem, Washington is particularly vulnerable due to certain factors. For example, the winds off of our coast tend to displace the surface water and bring deeper, colder, more carbon rich - and therefore more acidic - water up from the depths. Some of our human activities, such as overuse of fertilizer, failing septic systems and polluted runoff from the land, contribute to the problem.

A blue ribbon panel - the first of its kind in the nation - has been formed as part of the Governor's Washington Shellfish Initiative. By October 1, 2012, it will make recommendations to the Governor and to the National Oceanic and Atmospheric Administration on what Washington can do to reduce the impacts of ocean acidification on Washington's shellfish industry and other marine resources.

In my latest "Conversations on Washington's Future" message, I share what I and other members of the panel learned about the threat of ocean acidification, and where we will focus our energies over the next six months.

You can follow the progress of the panel at our web site: Ocean Acidification — Science & Actions in Washington State.

See more Conversations on Washington's Future.

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