It's a summertime sequel for OSU biologists. For the sixth straight year the oxygen-depleted "Dead Zone" has returned off the Oregon coast.

The evidence, though not yet definitive, points to global warming as the cause:

In 2002, Chan says researchers thought Oregon's dead zone was an anomaly brought on by a perfect storm of changes in wind and water circulation patterns. However, he adds, "now we're seeing that the system is very sensitive, and that a little more mild [winds] might put us in this state year after year." If that occurs, it could turn a rich and productive ocean ecosystem into an underwater desert. (Link)

The slightly good news, as it were: the dead zone is a little bit smaller this year.

That is not as bad as last year, when scientists plotted a dead zone that stretched from southern Oregon to the tip of Olympic Peninsula in Washington, a distance of nearly 300 miles. (Link)