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Disassociation of methane hydrates due to ocean temp. changes.

Discussion in 'Environmental Discussion' started by F8L, Oct 1, 2007.

  1. F8L

    F8L Protecting Habitat & AG Lands

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    Many of you are probably very familiar with this idea. It is believed to be one of the major contributors to the largest extinction in the history of the planet, the Permian extinction.

    I am posting this as an illustrative example of what a massive release of methane hydrates (also called clathrates) due to disassociation after ocean temperatures rise high enough to break down the molecular bonds between "water" and methane.

    For an interesting example of methane hydrate disassociation in a lab setting start watching around the 6min mark.

    The Permian Mas Extinction.

    This idea has been expressed in many articles and even documentaries (Dimming the Sun, Global Warming: The Signs and the Science)but I rarely see it show up as a concern in internet forums or even daily discussions. Is there something I am missing and that is why not many people seem at all concerned?
     
  2. patsparks

    patsparks An Aussie perspective

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    I thought it was all about a massive fish fart but looks worse than that.
     
  3. chogan

    chogan New Member

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    <div class='quotetop'>QUOTE(F8L @ Oct 1 2007, 02:55 AM) [snapback]519730[/snapback]</div>
    This is one of the changes that I just turn a blind eye to, because a large methane release would ... well, I just won't think about it.

    As usual, realclimate.org has a good discussion of the issue:

    http://www.realclimate.org/index.php?p=227

    My main takeaway from that discussion is that catastrophic release is an unlikely scenario. Instead, you'd have small, piecemeal releases over a timescale large enough to allow the released methane to degrade into C02. And in fact, we are currently having small ongoing releases from methane clathrates under the eroding Siberian coastline. There is evidence that geologists interpret as showing massive gas releases from the ocean bottom ("pockmarks"), and there were apparent methane releases coincident with the cycle of ice ages (ie, releases at peak global temperature).

    So, in general I trust realclimate.org to get the facts straight, and their take on it is that the most likely global impact of clathrates would be to add modestly to GHG emissions over the course of centuries, but not to pose a significant hazard for catastrophic release.
     
  4. qbee42

    qbee42 My other car is a boat

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    <div class='quotetop'>QUOTE(patsparks @ Oct 1 2007, 03:12 AM) [snapback]519731[/snapback]</div>
    Do fish farts bubble?

    Tom
     
  5. F8L

    F8L Protecting Habitat & AG Lands

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    <div class='quotetop'>QUOTE(chogan @ Oct 1 2007, 04:27 AM) [snapback]519758[/snapback]</div>
    Thanks for the link chogan, I'll check it out when I get home from work and comment then. :)
     
  6. MarinJohn

    MarinJohn Senior Member

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    after watching the link F8L provided, the 'second phase' of extinction whereby there was an abrupt death of everything in the sea, I was reminded of an article in our local paper about recurring and expanding 'dead zones' off our coast:

    http://www.coastalpost.com/07/09/25.html