It’s a gas, gas, gas

arcticmethane.jpg It’s not good news. The USA’s National Oceanic and Atmospheric Administration (NOAA) has produced its annual report on greenhouse gas levels in the atmosphere, and carbon dioxide concentration continues its accelerated growth. And there are signs that methane levels are beginning to rise, after a decade of remaining more or less static. The BBC reports:

NOAA figures show CO2 concentrations rising by 2.4 parts per million (ppm) from 2006 to 2007. By comparison, the average annual increase between 1979 and 2007 was 1.65ppm.

The methane rise is worrying because it’s a very powerful greenhouse gas (23 times as effective at trapping heat as CO2), and there are a number of positive feedbacks that could come into play as the planet warms. From the NOAA release:

Rapidly growing industrialization in Asia and rising wetland emissions in the Arctic and tropics are the most likely causes of the recent methane increase, said scientist Ed Dlugokencky from NOAA’s Earth System Research Laboratory. ”We’re on the lookout for the first sign of a methane release from thawing Arctic permafrost,” said Dlugokencky. “It’s too soon to tell whether last year’s spike in emissions includes the start of such a trend.”

Permafrost is one thing, methane hydrates are another. Sometimes called burning ice, methane hydrates (aka clathrates) are a mixture of ice and methane that exist in large quantities on the sea floor – and there are particularly large amounts in the shallow Arctic seas north of Russia and Siberia (more info at Climate Progress). At the recent European Geophysical Union conference in Vienna, a Russian scientist discussed the issue. From SpiegelOnline:

In the permafrost bottom of the 200-meter-deep sea [off the northern coast of Siberia], enormous stores of gas hydrates lie dormant in mighty frozen layers of sediment. The carbon content of the ice-and-methane mixture here is estimated at 540 billion tons. “This submarine hydrate was considered stable until now,” says the Russian biogeochemist Natalia Shakhova, currently a guest scientist at the University of Alaska in Fairbanks who is also a member of the Pacific Institute of Geography at the Russian Academy of Sciences in Vladivostok.

The permafrost has grown porous, says Shakhova, and already the shelf sea has become “a source of methane passing into the atmosphere.” The Russian scientists have estimated what might happen when this Siberian permafrost-seal thaws completely and all the stored gas escapes. They believe the methane content of the planet’s atmosphere would increase twelvefold. “The result would be catastrophic global warming,” say the scientists.

The SpeigeOnline article is worth reading in full. Shakova’s observations of methane emissions hint at an explanation for the increase in global atmospheric methane. If that’s the case – and its too early to say for sure – then we may be seeing the beginnings of one of the most worrying of the positive carbon cycle feedbacks – one that could potentially make anything we do to cut CO2 emissions the equivalent of pissing in the wind.

[Hat tip for the Spiegel piece to No Right Turn – I’m frankly amazed the EGU paper hasn’t had much more coverage in the world’s media.]

[Update for the interested: The EGU abstract for Shakhova’s paper is here [PDF]. Here’s the last few words:

“…we consider release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time. That may cause ~ 12-times increase of modern atmospheric methane burden with consequent catastrophic greenhouse warming.”

“Abrupt release at any time”. That’s truly alarming.]

11 thoughts on “It’s a gas, gas, gas”

  1. I don’t see how the Spiegel piece would make a jot of difference to the fact that, for a long time now, methane has a far bigger effect than CO2. Madness.

  2. This phrase in the story is very confusing: “Siberian permafrost-seal thaws completely and all the stored gas escapes”. It implies that some of it is in gaseous form already and just being held in by a “seal” on top, but I don’t think that’s true. Rather, once the permafrost layer melts it will still take some time for the hydrates to decompose and release the gas. How much time, I have no idea. Perhaps David Archer would be willing to comment on this.

    The other question I have is how this a large quantity of hydrates would have survived the Holocene thermal maximum (which IIRC had a considerable warming effect in the Arctic) but be vulnerable now.

  3. Cindy

    I guess you would call it relatively climate friendly because tapping the methane and burning it (in say a power station) gives you electricity and CO2 and possibly some spare heat to use if we get really clever.

    If I had a choice between a) a massive release of methane and b) a controlled release of CO2 plus some useful byproducts I’d go for b) every time.

    Of course the choice isn’t quite that simple.

    Good question from Steve Bloom re the HTM.

  4. There was a presentation at the NZ oil and gas conference in Feb on NZ methane hydrates. Apparantly a resource about 800tcf(Maui was about 4tcf). Much lower practical estimate but still greater than all of Taranaki conventional gas.

    Crown minerals doc 5Mb file

    Also USGS presented on the global resource

    here 2Mb

  5. I’ve updated the post to point to Shakhova’s abstract from the EGU. Not pleasant reading for those of a nervous disposition.

    I appears that there’s a “permafrost cap” over the bulk of the methane hydrates, and that present leakage is through faults and discontinuities in that “cap”.

    As for the Holocene Thernal Maximum, that’s a very good question. Kaufman et al, Holocene thermal maximum in the western Arctic (0–180W) (pdf), suggests that the “lingering” residual Laurentide ice sheet over North America could have had a marked impact on Arctic climate. The forcings involved, being orbital (Milanokovitch) would have been distinctly different (ie, perhaps not so much heat being shipped north by the Atlantic).

    {Edited to add] And then there’s the fact that the recent emergence from an ice age may have created a thick permafrost layer – thick enough to survive the warming. Hansen thinks we’re now past HTM temps…

  6. This is off topic but I heard on Morning Report news summary: “Co2 levels have been this high in the past”…..? I have been searching for some new findings but can’t find any reference.

  7. Hi john,

    That’s both true and irrelevant. CO2 levels in deep geological time have been well above today’s levels (see image here). But over the last 4 million years (the current sequence of ice ages), maximum CO2 reached during interglacials is about 290/300ppm, dropping to 180ppm during ice ages. We’ve pushed that to 385 ppm, and (surprise!) it’s getting warmer.

  8. There have been several items on the ETS (Emmissions Trading Scheme) in the news recently.

    The report from the Sustainability Council

    “The proposed rules for the Emissions Trading Scheme (ETS) will involve huge transfers of wealth but make very little difference to New Zealand’s greenhouse gas emissions in the next five years”

    “agriculture receives a net subsidy of $1.31 billion up to 2012”

    got (at least according to Stuff) no coverage in the newspapers, and nor did supporting press releases from the NZ Business Council for Sustainable Development. They were interviewed yesterday on National Radio though.

    On the same day, an NZIER report

    made great headlines:

    “The Government’s proposed Emissions Trading Scheme could cost New Zealand 20,000 jobs, reduce agriculture exports, cut wages and slash almost $6 billion from gross domestic product.”

    and vigorous comments on the Stuff blog. However, you only have to read to page 7 to find that their model predicts 42% GDP growth from 2007 to 2025 under the ETS, vs 44% without it – that’s where the $6b comes from. ie it affects about 1 part in 20 of our economic growth. Not such a great headline.

    While I am not an economist, I am not convinced of the value of this kind of modelling. Their assumptions include
    “no comprehensive global commitment to reducing CO_2” and “All of our scenarios are based on an assumed international price of carbon equivalent to $40 per tonne of CO2-e in 2008 prices”; the alternative scenario is that
    “In our ‘NZ Pays’ simulations we assume that it does so by paying for emission reductions abroad.” Nor did I see any mention of possibly much greater reductions being required after 2012.

    However, both the Sustability and the NZIER reports agree that the phase-in period, especially for agriculture, is much too long.

    It seems kind of ironic that after decades of right-wing economists promoting auctions and trading as sound market-based solutions for these situations, the moment the government tries to implement one they are up in arms! They should have been speaking up when we signed Kyoto, it’s a bit late now.

    How about some reports from economists on how we can actually cut our emissions by 50% by 2050 (John Key’s “50 by 50” – haven’t heard so much about that lately!)

    How about some leadership from local councils? When local councils started declaring themselves nuclear free in the late 1970s everybody laughed, but it led to the whole country becoming nuclear free in 1984.

    For that matter, how about some actual leadership from the government? I would like to see New Zealand become a world leader in reducing GHG emissions. It seems you can win a medal from the UN without actually doing anything.



  9. See probing interview of our PM on BBC Hard Talk about our so-called “carbon neutral” goal. Great questions around our coal exports.

    re: “I’m not an economist”: Sir Nicholas Stern has issued new report on economics of carbon trading (although obviously a global view rather than NZ-specific), etc here:

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