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Thread: the elephant in the living room....

  1. #1
    Member homerdave's Avatar
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    Exclamation the elephant in the living room....

    this is some serious stuff, folks, and not getting the attention it warrants!
    one of the first major casualties of ocean acidification will be salmon, as the pteropodss that young salmon rely on are one of the first trophic levels to crash....


    FOR IMMEDIATE RELEASE
    Aug. 11, 2009

    Fairbanks, Alaska
    most productive in the world may also make them the most vulnerable to ocean
    acidification. According to new findings by a University of Alaska Fairbanks
    scientist, Alaska¹s oceans are becoming increasingly acidic, which could
    damage Alaska¹s king crab and salmon fisheries.

    This spring, chemical oceanographer Jeremy Mathis returned from a cruise
    armed with seawater samples collected from the depths of the Gulf of Alaska.
    When he tested the samples¹ acidity in his lab, the results were more acidic
    than expected. They show that ocean acidification is likely more severe and
    is happening more rapidly in Alaska than in tropical waters. The results
    also matched his recent findings in the Chukchi and Bering Seas.

    ³It seems like everywhere we look in Alaska¹s coastal oceans, we see signs
    of increased ocean acidification,² said Mathis.

    Often referred to as the ³sister problem to climate change,² ocean
    acidification is a term to describe increasing acidity in the world¹s
    oceans. The ocean absorbs carbon dioxide from the air. As the ocean absorbs
    more carbon dioxide, seawater becomes more acidic. Scientists estimate that
    the ocean is 25 percent more acidic today than it was 300 years ago.

    ³The increasing acidification of Alaska waters could have a destructive
    effect on all of our commercial fisheries. This is a problem that we have to
    think about in terms of the next decade instead of the next century,² said
    Mathis.

    The ocean contains minerals that organisms like oysters and crabs use to
    build their shells. Ocean acidification makes it more difficult to build
    shells, and in some cases the water can become acidic enough to break down
    existing shells. Mathis¹ recent research in the Gulf of Alaska uncovered
    multiple sites where the concentrations of shell-building minerals were so
    low that shellfish and other organisms in the region would be unable to
    build strong shells.

    ³We¹re not saying that crab shells are going to start dissolving, but these
    organisms have adapted their physiology to a certain range of acidity. Early
    results have shown that when some species of crabs and fish are exposed to
    more acidic water, certain stress hormones increase and their metabolism
    slows down. If they are spending energy responding to acidity changes, then
    that energy is diverted away from growth, foraging and reproduction,² said
    Mathis.

    Another organism that could be affected by ocean acidification is the tiny
    pteropod, also known as a sea butterfly or swimming sea snail. The pteropod
    is at the base of the food chain and makes up nearly half of the pink
    salmon¹s diet. A 10 percent decrease in the population of pteropods could
    mean a 20 percent decrease in an adult salmon¹s body weight.

    ³This is a case where we see ocean acidification having an indirect effect
    on a commercially viable species by reducing its food supply,² said Mathis.

    The cold waters and broad, shallow continental shelves around Alaska¹s coast
    could be accelerating the process of ocean acidification in the North,
    Mathis said. Cold water can hold more gas than warmer water, which means
    that the frigid waters off Alaska¹s coasts can absorb more carbon dioxide.
    The shallow waters of Alaska¹s continental shelves also retain more carbon
    dioxide because there is less mixing of seawater from deeper ocean waters.

    Ask any coastal Alaskan and they will tell you that Alaska¹s waters are
    teeming with biological life, from tiny plankton to humpback whales. All of
    these animals use oxygen and emit carbon dioxide. Mathis and other
    scientists call this the ³biological pump.²

    ³We are blessed with highly productive coastal areas that support vast
    commercial fisheries, but this productivity acts like a pump, absorbing more
    and more carbon dioxide from the atmosphere,² said Mathis. ³Because of this,
    the acidity of Alaska¹s coastal seas will continue to increase, and likely
    accelerate, over the next decade.²

    Mathis said that it is still unclear what the full range of effects of ocean
    acidification will be, but that it is a clear threat to Alaska¹s commercial
    fisheries and subsistence communities.

    ³We need to give our policy makers and industry managers information and
    forecasts on ocean acidification in Alaska so they can make decisions that
    will keep our fisheries viable,² said Mathis. ³Ecosystems in Alaska are
    going to take a hit from ocean acidification. Right now, we don¹t know how
    they are going to respond.²

    CONTACT: Carin Stephens, public information officer, at 907-322-8730, or via
    e-mail at stephens@sfos.uaf.edu. Jeremy Mathis, assistant professor of
    oceanography, at 907-474-5926, or via e-mail at jmathis@sfos.uaf.edu.

    ON THE WEB: www.sfos.uaf.edu/oa

    ___________
    Alaska Board of Game 2015 tour... "Kicking the can down the road"
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    Interesting. Thanks Dave.

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    Default Yes Interesting

    Thanks Dave!

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    Great read Dave! i wonder what impact it has had already

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    they were doing the same research at the "Noah?" facility in Kodiak

    If you cant stand behind the troops in Iraq.. Feel free to stand in front of them.

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    I've heard a couple of stories on this on NPR with in the last couple of days. Wonder if this has anything to to with the king runs this year? Scary to think about how fast thing could go down hill if this plays out like they predict.

    KK

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    Interesting factoid in the article. Acidification level today is compared with an "estimated" level of 300 years ago. I'd like to see a more current number, say of 30 years, to compare it to, rather than a guess of what it was like 300 years ago.

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    Default pH levels now and then

    It is indeed an interesting article- thanks Dave for posting it.

    Acidic levels or pH is a complex subject in itself even without the biological aspects. I worked for several years on an industrial wastewater project where we were neutralizing acid waste for discahrge to a river. Measuring pH accurately is hard enough I found. Complicating measurment even more is the fact that the pH of a sample can change from the collection point to the lab- sometimes drastically due to such factors as buffers, temperature, gas dissolved from the air etc. How you could "estimate" what it was 300 yrs. ago must be pretty iffy IMO.

    As pointed out in the article colder water absorbes more CO2 so it becomes more acidic or has a lower ph. Therefore global warming would be a plus from the aspect of acidity.

    Quote Originally Posted by willphish4food View Post
    Interesting factoid in the article. Acidification level today is compared with an "estimated" level of 300 years ago. I'd like to see a more current number, say of 30 years, to compare it to, rather than a guess of what it was like 300 years ago.
    Living the urban lifestyle so I can pay my way and for my family's needs, and support my country. And you?
    ".. ask not what your country can do for you, ask what you can do for your country" JFK

  9. #9

    Default Science questions

    The article was not written clearly to distinguish whether the more acidic levels in Alaska's waters are due to:

    a) increased range of CO2 in the atmosphere over the past 300 years - in which I would like to know how the acidity estimates of sea water 300 years ago along the Alaska coastline were made so as to have a basis of fair comparison, or

    b) Alaska waters are naturally more acidic because it is teaming with much more marine life - during the summer time for the large plankton blooms - in which case the author should do a summer water ph value against a winter ph value when there isn't the large plankton bloom as a variable.

    c) lack of a deep water mixing zone for the Bering Sea continental shelf area and the Pacific Ocean. Some comparisons to the Gulf of Alaska would be helpful in the report to isolate out this lack of clarity, as there is definately mixing along the Gulf of Alaska continental shelf.

    Also, as an aside, it is interesting to note that changes in plankton levels are related to potential weight changes in salmon, but we never seem to be concerned on how many pink and chum salmon hatchery fish get dumped into the ocean to go feed in the same grounds. What about a study on effects of increased competition from hatchery fish in the feeding grounds on the weight and size of wild salmon.

    On second thought, if it is all considered wild salmon anyway, who really cares if it is a wild or hatchery salmon as long as it is sold under the wild Alaska salmon banner.

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    Default AP News finally picked up today

    I found an AP news release story on this today - Aug. 24th.
    Living the urban lifestyle so I can pay my way and for my family's needs, and support my country. And you?
    ".. ask not what your country can do for you, ask what you can do for your country" JFK

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