More evidence of climate change: Arctic methane hydrates evaporating


It’s a pretty picture, but it should strike a bit of fear once you know what it is.

New Scientist explains:

Sonar image of methane plumes rising from methane hydrates on the Arctic Ocean floor; image from National Oceanography Centre, Southampton (Britain)

Sonar image of methane plumes rising from methane hydrates on the Arctic Ocean floor; image from National Oceanography Centre, Southampton (Britain)

It’s been predicted for years, and now it’s happening. Deep in the Arctic Ocean, water warmed by climate change is forcing the release of methane from beneath the sea floor.

Over 250 plumes of gas have been discovered bubbling up from the sea floor to the west of the Svalbard archipelago, which lies north of Norway. The bubbles are mostly methane, which is a greenhouse gas much more powerful than carbon dioxide.

The methane is probably coming from reserves of methane hydrate beneath the sea bed. These hydrates, also known as clathrates, are water ice with methane molecules embedded in them.

The methane plumes were discovered by an expedition aboard the research ship James Clark Ross, led by Graham Westbrook of the University of Birmingham and Tim Minshull of the National Oceanography Centre, Southampton, both in the UK.

Fortunately, the methane is not making it out of the water — yet.  The gases are absorbed before they get to the surface — but that increases ocean acidity.  If, and when, the methane hits the atmosphere, it will contribute to greenhouse warming of the planet.  This could create a runaway heat effect:  Warmer waters cause hydrates to release methane to the atmosphere, which causes the atmosphere to warm more, faster.

Scientists have not dismissed all other possibilities, but methane hydrate melting is the most likely cause:

Cohen cautions that the Arctic methane may not be from hydrate, but could be coming from the methane’s primary source, which might be deep within the Earth.

If that was the case, the warming of the West Spitsbergen current may not be to blame.

He says that the large amounts of methane being released make this unlikely, however: “If the methane is all primary, it would be an unprecedented amount.” So the idea that the hydrates are at least partly to blame is more plausible. “It’s not definitively proven, but it’s certainly reasonable,” he says.

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8 Responses to More evidence of climate change: Arctic methane hydrates evaporating

  1. […] Cool SONAR pictures of methane bubbling up from the floor of the Arctic Ocean, but scary once you realize what they are, at this vintage post at Millard Fillmore’s Bathtub. […]

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  2. Climate change is getting worse day by day.I think we should have make appropriate remedy measures against these ones.

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  3. Ed Darrell says:

    First, the stuff is coming from areas where hydrates are known to exist, but gas deposits are not. Second, I gather from reports that the two forms of methane look different on SONAR — that’s what SONAR training is all about.

    Warming is invoked because methane hydrates are frozen water, essentially, with trapped methane. Warming oceans thaw the ice, and the methane bubbles up. As predicted by scientists who warned of the bad effects of global climate change that manifests as warming, we’re seeing these hydrates melt, and the methane is bubbling up. It’s the best explanation we’ve got. The predictions are following earlier observations almost exactly. Warming is invoked because that appears to be the cause.

    This area of the Arctic has been extensively explored by the U.S. Navy in their submarine hunting expeditions. For 50 years this tract has been observed. It’s not like this is the first look down there.

    Yes, methane is all through the universe, one of the building blocks of life and abiogenesis. But under the ocean floor, it’s generally frozen in methane hydrates. And now the hydrates appear to be thawing, releasing the gases.

    If you have information to make the case this isn’t methane hydrate melting, make the case. I see you flailing a bit trying to find reasons to deny the obvious, but no contrary case.

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  4. ScientistForTruth says:

    Just a thought. The UK and Norway extract large amounts of oil and natural gas (=methane) from under the sea bed, and there is talk of large deposits of oil and natural gas under the Arctic seabed. Why can’t these plumes be natural gas escaping from oil and gas deposits? In the Middle East pools of oil percolated to the surface and formed pools before commercial discovery and extraction (at least as far back as 4000 years ago according to the Bible, where they are termed “bitumen pits”: “the valley of Siddim was full of bitumen pits” [near the Dead Sea]. This oil product, also termed and as pitch and asphalt, was used commercially for mortar and for sealing water craft thousands of years ago). Doubtless natural gas escaped as well. The Chimaera gas seep, near Antalya in Turkey, has been continuously active for thousands of years.

    Why does global warming have to be invoked? Just because methane has been noticed for the first time here by sonar doesn’t mean it hasn’t been creating plumes for thousands of years, especially as there are no bubbles reaching the surface, which would have been easier to spot. The article itself says “Almost none of the Arctic has been surveyed in a way that might detect a gas release like this”.

    Let’s not forget that methane doesn’t have to come from ‘trapped’ decomposed fossil material anyway – it’s found on moons and planets. Methane is produced by reacting iron oxide, calcium carbonate, and water under high temperature and pressure – all of which can be in abundance beneath the sea floor: it might be forming quite naturally and could continue to do so for millennia.

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  5. j a higginbotham says:

    Ed:”The gases are absorbed before they get to the surface — but that increases ocean acidity.”
    Ed:”The methane reacts, and one of the byproducts is CO2. CO2 reacts to form acids.”

    NS:Just because it fails to reach the surface doesn’t mean the methane is harmless, though, as some of it gets converted to carbon dioxide.

    So methane does not directly affect ocean acidity. It is just as valid then to say that oil or coal or wood or people increase ocean acidity; burning any of them liberates CO2.

    I didn’t see anything in the article (or links) about how the methane reacts, specifically whether it is biologic or chemical.

    Here are a few possibly related abstracts from the web:

    Titre du document / Document title
    Methane oxidation potential in the water column of two diverse coastal marine sites
    Auteur(s) / Author(s)
    KELLEY Cheryl (1) ;
    Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)
    (1) Dept. of Geological Sciences, University of Missouri, 101 Geological Sciences Building, Columbia, MO 65211, ETATS-UNIS
    Résumé / Abstract
    Methane oxidation in the water column was investigated at two nearshore marine environments with relatively high concentrations of dissolved methane. In the northern Gulf of Mexico, high methane oxidation rates were observed at the pycnocline, with the highest oxidation rate corresponding to the most negative bacterial δ13C values. These low isotopic values occurred during the winter when overall bacterial productivity was low, suggesting that at this time of the year, methanotrophs in the Gulf could make up a significant portion of the overall bacterial assemblage. Although methane oxidation also occurred during more productive times (i.e., summer), the isotopic signal of methane oxidation was not observed in the bacterial biomass because of the higher overall bacterial productivity. The other site, Cape Lookout Bight, NC, is a small marine embayment where methane is produced in the organic-rich sediments. No measurable rates of methane oxidation in the water column occurred, and no anomalously low δ13C values of the bacterioplankton were measured. In both environments, methane production and oxidation appear to be spatially coupled, occurring at/near the pycnocline in the northern Gulf of Mexico and at the sediment-water interface at Cape Lookout Bight, NC.

    Letters to Nature
    Nature 327, 226 – 229 (21 May 1987); doi:10.1038/327226a0

    Methane oxidation and methane fluxes in the ocean surface layer and deep anoxic waters

    B. B. Ward*, K. A. Kilpatrick*, P. C. Novelli† & M. I. Scranton†

    *Institute of Marine Resources, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093, USA
    †Marine Science Research Center, State University of New York, Stony Brook, Long Island, New York 11794, USA

    Methane is supersaturated in sea water, and is typically at its maximum concentration in near-surface waters, which could support a significant sea-air flux. The magnitude and variability of the flux depends on the mechanisms which produce and consume methane in sea water. Here, we compare measured biological oxidation rates of methane with the diffusional fluxes computed from concentration gradients in the surface layer of the ocean, and show that oxidation of methane in sea water is a mechanism which modulates the flux of methane from marine waters to the atmosphere. Methane fluxes and oxidation rates were investigated in surface waters, at the oxic/anoxic interface and in deep anoxic waters of the Cariaco Basin. Measured oxidation rates were equivalent to 5% of the methane flux into oxygenated waters from the methane-rich deep waters and 10% of the flux into surface waters from the subsurface methane maximum. Thus oxidation was not sufficient to prevent a net sea-air flux. The total methane oxidation rate in the basin amounted to 1.5% of total primary production in the surface layer. Only a small fraction of oceanic primary production would be required to cycle through the methane pool to support the global atmospheric flux from the ocean1.

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  6. Ed Darrell says:

    The methane reacts, and one of the byproducts is CO2. CO2 reacts to form acids.

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  7. j a higginbotham says:

    How does methane increase ocean acidity? Is something eating it and producing acids as waste products?

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  8. george.w says:

    That is a scary picture. I’m becoming a little numb to things scaring the crap out of me; resistant bugs, global warming, a half-billion people soon without water, idiot senators, etc.

    Methane is also starting to bubble out of permafrost, too. And “much more powerful” is right; it may be 25 times more potent a greenhouse gas than carbon dioxide.

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