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Methane Hydrates: What’s the worst — and best — that could happen?

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"Methane Hydrates: What’s the worst — and best — that could happen?"

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methane_hydrate.jpgMethane hydrates (or clathrates), “burning ice,” are worth understanding because they could affect the climate for better or worse. You can get the basics here on

… a solid form of water that contains a large amount of methane within its crystal structure [that] occur both in deep sedimentary structures, and as outcrops on the ocean floor.

The worst that could happen is a climate catastrophe if they were released suddenly, as some people believed happened during the Permian-Triassic extinction event and the Paleocene-Eocene Thermal Maximum. The best that could happen is if they could be recovered at a large scale safely — then they would be an enormous new source of natural gas, the lowest-carbon and most efficient-burning fossil fuel.

A recent workshop was held — “Vulnerability and Opportunity of Methane Hydrates Workshop,” IIASA, 13-14 March 2008. You can find most of the presentations here. Science magazine (here, subs. req’d) ran a summary of the meeting recently, which I will reprint below:

Weighing the Climate Risks of an Untapped Fossil Fuel

John Bohannon

As the energy industry hungrily eyes methane hydrates, scientists ponder the fuel’s impact on climate

VIENNA, AUSTRIA–A recent workshop on methane hydrates felt like a powwow of 19th century California gold prospectors, looking ahead to both riches and peril. Sizing up the prize, Arthur Johnson, a veteran geologist of the oil industry who is now an energy consultant based in Kenner, Louisiana, predicted that “within a decade or two, hydrates will grow to 10% to 15% of natural gas production,” becoming a more than $200 billion industry. And the peril? “The worst-case scenario is that global warming triggers a decade-long release of hundreds of gigatons of methane, the equivalent of 10 times the current amount of greenhouse gas in the atmosphere,” said David Archer, a climate modeler at the University of Chicago in Illinois. Although no current model predicts such an event, said Archer, “we’d be talking about mass extinction.”

When methane molecules become locked in atomic cages of water called clathrates, they form icy chunks that ignite when lit. These solids form wherever methane encounters water at high pressure and low temperature. The necessary conditions reign in permafrost and in some sea-floor sediments, forming a “ring around the bathtub” on continental slopes. This exotic fuel was discovered by the Soviet petroleum industry more than 3 decades ago, but even a few years ago many doubted its commercial potential (Science, 13 February 2004, p. 946). After several successful pilot drilling studies and heavy research investment over the past 4 years, says Johnson, “the question now is not whether industry will exploit hydrates but how soon.”

Considering the skyrocketing price of oil, the answer seems to be soon, says one of the workshop organizers, NebojÅ¡a Nakicenovic, an energy economist here at the International Institute for Applied Systems Analysis (IIASA) outside Vienna. “And yet hydrates are absent from most of the climate discussions,” he says, “and virtually absent from the IPCC fourth assessment report,” last year’s 1000-page tome by the Intergovernmental Panel on Climate Change (Science, 11 May 2007, p. 812). The goal of the IIASA workshop was to bring together researchers from all the different fields that touch hydrates–from chemistry and economics to climate impact–to get an “interdisciplinary perspective” on the uncertainties.

“It’s clear that one of our biggest knowledge gaps is figuring out the distribution,” says Michael Riedel, a marine geophysicist at McGill University in Montreal, Canada. “We still don’t know how much there is in the world, not even within an order of magnitude.”

Another crucial gap is the flux of methane, which drives hydrate formation over time. The largest amounts of methane hydrates are thought to reside in sub-sea-floor sediments. In a newly built sea-floor-monitoring network called NEPTUNE off the western coast of Canada, Riedel is part of a team studying methane-spewing vents to get a handle on their flow rate and marine chemistry. Where the conditions are just right, methane hydrates form caps over pockets of such gas. These not only are sweet spots for those who want to tap hydrates for energy but also represent a major worry for climate modelers.

“If the sea floor warms up by a few degrees Celsius, the most vulnerable hydrates will melt, and then you’re going to get a massive release of methane,” says Euan Nisbet, a marine geologist at Royal Holloway, University of London. That warming and release is expected to take centuries or even millennia even in the most extreme climate scenarios. Riedel says the methane bubbles from seafloor vents are sponged up by the ocean water. But if a methane release were large and shallow enough, it would reach the atmosphere, says Archer. What is unclear is whether the climate system has methane-driven positive feedback mechanisms that could lead to abrupt climate change.

Johnson threw cold water on the scenario of a massive release of submarine hydrate-trapped methane to the atmosphere. Most hydrate deposits found so far “are as deep as a kilometer below the sea floor,” he says, “and they aren’t going anywhere.” Walter Oechel, an ecologist and carbon-cycle expert at San Diego State University in California, doesn’t find the “doom-and-gloom scenarios” very likely either. “The real story for me is hydrates as yet another chronic contributor to greenhouse gas emissions,” he says.

Others considered methane hydrates part of a greenhouse gas solution. A plan proposed by Vladimir Yakushev, a geologist at Gazprom, the world’s largest natural gas corporation, based in Moscow, involves simultaneously extracting methane and methane hydrates while pumping liquefied carbon dioxide into the underground spaces left behind. Researchers also discussed the idea of using hydrates for electricity generation or even manufacturing on the spot. “We have to try to make it carbon-neutral if we’re serious about climate change,” says Nisbet.

The overarching question of whether methane hydrates should play a major role in climate change debate was up for grabs. Considering the workshop discussions, “the methane hydrate issue is one risk that shouldn’t drive policy considerations at the moment,” concludes Brian O’Neill, an IPCC author and climate modeler at the National Center for Atmospheric Research in Boulder, Colorado. “There are bigger fish to fry.” But Neil Hamilton, director of the International Arctic Programme for the World Wildlife Fund, based in Oslo, Norway, says, “It’s absolutely shocking that hydrates have gotten so little attention.” The risk of a massive methane release, however unlikely, “is reason enough for very serious concern,” he says. More meetings like these are clearly needed.

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5 Responses to Methane Hydrates: What’s the worst — and best — that could happen?

  1. Tom says:

    I noticed there wasn’t any mention of the “pingo like features” in the Beaufort Sea. Their depth ranges from 20m to 200m, far less than a kilometer.

  2. john says:

    I have three concerns about the attitudes documented in this post.

    First, the scientists dismiss “gloom and doom” scenarios out of hand.

    I say not so fast. and here’s why.

    Hydrates form along a gradient defined by temperature and pressure. So what? Well, that means a great deal of them are in relatively shallow — but cold – seas and even on land in perma-frost.

    In fact, estimates are that more than 10% of the world’s hydrates are located on-shore in arctic permafrost; and a sizable — although not quantified — amount are in relatively shallow arctic seas. These are susceptible to melting from warming. And as we know, the polar regions are warming faster and will get hotter than the global average. So a sizable amount of the methane trapped in hydrates is vulnerable to release by warming.

    Even the deep sea stuff isn’t immune to releases — there are two confirmed large scale releases of methane from deep sea hydrates in the geologic record: One off the coast of Norway, one off the coast of North Carolina. More are suspected.

    So, any geologist worth his beans who glibly dismisses “gloom and doom” scenarios associated with hydrates either doesn’t know what he or she is talking about, or they are more amenable to playing craps with the planet than they should be.

    Second, since hydrates are quite dispersed and extremely volatile when disturbed, it will take extremely sophisticated technologies to recover them without substantial leakage. And we can’t afford releases of methane — a GHG 23 times stronger than CO2 — into the atmosphere. In the long run, attempts to exploit this “resource” in an environmentally safe manner are likely to be so complex and expensive that they would render it an economic dog.

    Third, we don’t need to recover the stuff. With a full court press on efficiency and renewables, we can leave the stuff where it is.

    The evidence from both the Permian mass extinctions and the Paleocene-Eocene Thermal maximum is pretty clear: Once started, methane hydrate releases can become self-reinforcing. No do overs. No going back. Just a giant Whoops.

    So, I would suggest that folks are grossly underestimating the danger posed by hydrates. But even if they weren’t, the danger they pose falls into the category of unlikely, but potentially cataclysmic. As Pascal noted, the only rational response to such risks is to act as if they were certain and do all we can to avoid them.

    Including letting this particular sleeping dog lie.

  3. David B. Benson says:

    Paleocene-Eocene Thermal maximum — Does not appear to be associated with releases of methane from deep sea clathrates. It does seem to be associated with the release of methane from bogs. This suggests that the methane in permafrost will go first, and anyway, there is probably enough methane there to do us in…

  4. Andy says:

    One explanation of the Paleocene-Eocene Thermal Maximum is release of methane due to volcanic intrusion and heating of sediments.

    There is enough methane in bogs in tropical zones, the Tundra, permafrost and shallow seas to pose huge dangers in addition to CO2 release / feedbacks and ice melt / feedbacks.

    People often forget it is the SYNERGY of all these processes which is the point.

    The mid-Pliocene (3 Ma) is the closest to the “experiment” Homo “sapiens” is conducting at present. CO2 rose to about 400 ppm, tempratures by 2 – 3 degrees, sea lelvels by 25+/- 12 metres. It is not clear to what extent methane was released at that stage.

    Homo enerctus appeared in the wake of the mid-Pliocene climate upheaval. It remains to be seen (not by us) what kind of species would appear in the wake of the Anthropocene???

  5. Yoron says:

    Stop wondering:)
    Read and be enlightened-

    First of all, what is Methane clathrate’s?
    http://en.wikipedia.org/wiki/Methane_hydrate

    About Canadian & Russian permafrost and Arctic Sea Ice.
    http://www.ucar.edu/news/releases/2008/permafrost.jsp

    And then this.
    The methane time bomb at
    http://www.independent.co.uk/environment/climate-change/exclusive-the-methane-time-bomb-938932.html?startindex=110

    So we already have ‘chimneys’ under the ” the East Siberian Sea and the Laptev Sea, covering several tens of thousands of square kilometres, amounting to millions of tons of methane ” and the Russian tundra is melting too, creating small ‘lakes’ from which methane is released in the process.

    As for using it as ‘energy’:)
    Well, wouldn’t you say that we would need it frozen first?
    It doesn’t seems to cooperate here. does it.
    It seems that mother Earth has a different opinion of us than we our self have.
    Not so much masters of our Earth as locust, without thinking ability but with an insatiable greed.