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The Mystery of Oregon's 'Dead Zone'

Posted by ryuzaki0 on from the behind-the-scary-door dept.

Roland Piquepaille writes "The area off Cape Perpetua on the central Oregon coast is now a gigantic crab and fish graveyard. It was first discovered in 2002, but according to the Christian Science Monitor, researchers at Oregon State University (OSU) have taken a close-up look into this coastal dead zone. And things are getting worse. A few weeks ago, the researchers measured the level of dissolved oxygen in this part of the ocean. They found that levels were 10 to 30 times lower than normal, down to 0.5 milliliters per liter, a characteristic of hypoxia. And because they have no explanations about this phenomenon, they're even envisioning a total absence of oxygen, or anoxia. Read more for additional details and pictures about this mystery."

9 of 235 comments (clear)

  1. No explanation? by broothal · · Score: 4, Informative

    " And because they have no explanations about this phenomenon..."

    Let me help them out here a bit then. The Oregon zone appears when the wind generates strong currents carrying nutrient-rich but oxygen-poor water from the deep sea to the surface near shore, a process called upwelling. The nutrients encourage the growth of plankton, which eventually dies and falls to the ocean floor. Bacteria there consume the plankton, using up oxygen.

    No - I'm not so smart that I knew the answer, but google did - first (and several more) hit.

    1. Re:No explanation? by tigheig · · Score: 4, Informative
      Yes. It was discussed. Starting in the fifth paragraph of the linked article.

      Follow the link, it's a good article.

    2. Re:No explanation? by enharmonix · · Score: 5, Informative

      Hmm, we've been dealing with this in the Gulf for a while. It's recurrant - it goes away, then comes back the next year, and is caused by too much algae, which is basically fed by nitrogen rich runoff from ground water. IIRC, though, wind actually helps by mixing the water, so global warming shouldn't really enter into this picture. Not to say the article didn't quote somebody saying that, or that different climates won't affect things, but that's just what I heard. For anybody interested, there's a pretty scientific assessment of the phenomenon (in the gulf at least) here (I don't think anybody's linked to this yet, apologies if this is a dupe). Anyway, don't panic, Oregonians, you'll survive! Cheers.

    3. Re:No explanation? by Anonymous Coward · · Score: 3, Informative

      Y'know, maybe you should just read TFA, where this explaination is given:

      To be sure, the jury is still out on that connection, says Jane Lubchenco, a marine zoologist at Oregon State University who is heading up this day-long expedition. But, she adds, what she and her colleagues see is consistent with projections of global warming's effects on coastal winds in the spring and summer, which drive upwelling of nutrient-laden water.

      These effects - identified as early as 1990 by researcher Andrew Bakun, then with the National Oceanic and Atmospheric Administration's fisheries lab in Monterey, Calif. - turbocharge the upwelling. This overloads the waters with nutrients and spawns large algae blooms. The algae sink, die, and decompose, in a process that sucks oxygen out of the water and the topmost layer of sediment on the bottom, where many worms and shellfish live.

      Hey, that's exactly what the OP said!

  2. volcanic ridge/rift, most likely by nido · · Score: 3, Informative

    I guess it's called the Juan de Fuca Ridge.

    This dead zone is "most likely caused by underwater volcanism along the Juan De Fuca Ridge, which is about 20% volcanic along its 500 mile length. Occassional volcanic eruptions occur along the Ridge (Rift) which can create gigantic megaplumes of hot mineral water. Could be there is very little oxygen in the plumes, it most likely would have reacted with the minerals, leaving dissolved oxygen at nil."

    --
    Learn the rules so you know how to break them properly.
    www.teslabox.com
  3. Re:USA IS IGNORANT! by DrSkwid · · Score: 5, Informative

    Lets not forget that China & India are also not signees.

    Thus the three most populous continents on earth are simply not concerned.

    --
    There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
  4. No mystery - Polution by PietjeJantje · · Score: 4, Informative

    From the article:

    "This overloads the waters with nutrients and spawns large algae blooms. The algae sink, die, and decompose, in a process that sucks oxygen out of the water and the topmost layer of sediment on the bottom, where many worms and shellfish live."

    Fosfate/nitrate (among others) --> Nutritions for algae --> No oxygen

    The "mystery" is where the polution is coming from.

  5. Re:CSM or ZDNET - Which is it? by Anonymous Coward · · Score: 5, Informative

    This is nothing new. Roland Piquepaille has been submitting stories which invariably link to his own blog (which carries a pale imitaiton of the original article) for ages. There have been accusations that he is paying the slashdot editors for the service of publishing his stories. See http://www.google.com/search?q=roland.piquepaille+ site:Slashdot.org.

  6. It's just Roland the Plogger screwing up again by Animats · · Score: 5, Informative

    That's just a link to a Roland the Plogger blog, who doesn't understand the problem. Read the New York Times story, which has important facts the Plogger missed, like the fact that this has been happening for the past five years. The local paper, the Register-Guard, has a good story. "On the way down, the camera lens illuminates a nighttime blizzard, a flurry of broken chunks of plankton called "marine snow." This is evidence of what caused this year's hypoxia - an onslaught of nutrients brought to shallow coastal waters by wind-driven currents, whose decomposing structures suck up available oxygen."

    This is no mysterious dramatic event. It happens every year, but this year, it's worse than usual, possibly because ocean currents have shifted due to weather.