The threat from methane in the North

by Milan on February 18, 2010

in Climate change, Climate science, Wildlife

If catastrophic climate change is to be avoided, it is critical that the massive stock of greenhouse gas held in the Arctic permafrost and in undersea deposits called methane clathrates not be allowed to enter the atmosphere. The permafrost and clathrates contain methane: a gas that is about 25 times more powerful than carbon dioxide, when it comes to preventing infrared radiation from escaping into space, keeping it within the Earth system and warming the planet. As the planet heats up from human greenhouse gas emissions, the threat of all this methane getting released increases.

Right now, there is even more methane on Earth than there was before the Paleocene-Eocene Thermal Maximum (PETM), a period about 56 million years ago when the methane bound up in the north got released over the course of several thousand years. Back then, those emissions made the planet’s temperature rise between 5°C and 9°C – far beyond the level which would be dangerous for human beings. And remember that this warming is on top of whatever warming arises directly from human emissions. According to the modeling conducted by the Met Office in the United Kingdom, if our emissions continue on a business-as-usual course, they will generate 5.5 – 6.1°C of warming by 2100. Just imagine what impact melting clathrates and permafrost could have in addition.

The PETM happened fairly slowly, but was nonetheless accompanied by the extinction of about half the planet’s marine life. Other species migrated hundreds or thousands of kilometres, as the climate in different regions changed. There were no ice sheets during the PETM, whereas Earth currently has enough ice in Greenland and Antarctica to raise sea levels by more than sixty metres. Human-induced climate change is happening far faster than what happened during the PETM. That makes it even harder for plants and animals to adapt. It also means there is less time for negative feedbacks (like increased weathering of rocks) to blunt the edge of the warming.

In addition to the vanishing multi-year sea ice, we are already seeing worrisome degradation of the Arctic permafrost. For instance, researchers in Quebec have found that the edge of where permafrost is found in one region has moved 130 km in just 50 years. The threat of kicking off a PETM-type event is one major reason why the warming caused by human beings must be limited. Because the amount of warming we produce is directly related to how many fossil fuels we burn, it is critical that humanity make the conscious choice to limit our fossil fuel usage. For the sake of protecting a planet that provides the foundation for human prosperity and survival, we need to leave fossil fuels underground and move to a clean and renewable global energy system that can keep operating forever.

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. February 25, 2010 at 9:21 pm

Mallik 2002
GSC Bulletin 585:
Scientific results from the Mallik 2002 gas hydrate production well program

Edited by S.R. Dallimore and T.S. Collett
Co-editors: S.R. Dallimore, T.S. Collett, A.E. Taylor, T. Uchida, M. Weber, A. Chandra, T.H. Mroz, E.M. Caddel, and T. Inoue

The science and engineering results presented in this volume are truly extraordinary, as is the chronicle of the Mallik 2002 Gas Hydrate Production Research Well Program itself. Five countries participated in this partnership, with the lead agencies being Natural Resources Canada (Geological Survey of Canada), the Japan National Oil Corporation (JNOC), GeoForschungsZentrum Potsdam (GFZ), the United States Geological Survey (USGS), the United States Department of Energy (USDOE), the India Ministry of Petroleum and Natural Gas (MOPNG)-Gas Authority of India (GAIL), and the BP-ChevronTexaco Mackenzie Delta Joint Venture (formerly the BP-ChevronTexaco-Burlington Joint Venture). A substantially expanded science program for the well was enabled through the International Continental Scientific Drilling Program (ICDP).

The 63 technical research papers and accompanying databases presented in this publication are far reaching in their impact, and provide an extraordinary level of detail on one of the world’s most concentrated gas hydrate deposits. Important new work and insight are presented on gas hydrate production testing. New studies are reported on in situ physical and geophysical properties of gas hydrate, with complementary studies on an extensive coring program. New appraisals are presented on the relevance of gas hydrate to energy, climate, and geohazard research. We are proud of the efforts of all 300 scientists and engineers involved in the Mallik 2002 Gas Hydrate Production Research Well Program, and we hope that the body of work we have contributed to the public forum will leave a mark in this fast-growing and important research field.

The science and engineering results presented in this volume are truly extraordinary, as is the chronicle of the Mallik 2002 Gas Hydrate Production Research Well Program itself. Five countries participated in this partnership, with the lead agencies being Natural Resources Canada (Geological Survey of Canada), the Japan National Oil Corporation (JNOC), GeoForschungsZentrum Potsdam (GFZ), the United States Geological Survey (USGS), the United States Department of Energy (USDOE), the India Ministry of Petroleum and Natural Gas (MOPNG)-Gas Authority of India (GAIL), and the BP-ChevronTexaco Mackenzie Delta Joint Venture (formerly the BP-ChevronTexaco-Burlington Joint Venture). A substantially expanded science program for the well was enabled through the International Continental Scientific Drilling Program (ICDP).

The 63 technical research papers and accompanying databases presented in this publication are far reaching in their impact, and provide an extraordinary level of detail on one of the world’s most concentrated gas hydrate deposits. Important new work and insight are presented on gas hydrate production testing. New studies are reported on in situ physical and geophysical properties of gas hydrate, with complementary studies on an extensive coring program. New appraisals are presented on the relevance of gas hydrate to energy, climate, and geohazard research. We are proud of the efforts of all 300 scientists and engineers involved in the Mallik 2002 Gas Hydrate Production Research Well Program, and we hope that the body of work we have contributed to the public forum will leave a mark in this fast-growing and important research field.

Irwin Itzkovitch
Assistant Deputy Minister
Earth Sciences Sector
Natural Resources Canada

Tsuneo Shimamura
Executive Director, Member of the Board
Japan Oil, Gas and Metals National Corporation

Rolf Emmermann
Scientific Executive Director and Chairman of the Executive Board
GeoForschungsZentrum Potsdam, Germany

Charles Groat
Director
United States Geological Survey

V.K. Sibal
Director General
Directorate General of Hydrocarbons, India

Robert Ball
BP-ChevronTexaco Mackenzie Delta Joint Venture

Brad Tomer
Director, Office of Natural Gas
Strategic Center for Natural Gas and Oil
United States Department of Energy

. March 9, 2010 at 2:40 pm

Arctic Methane on the Move?
— david @ 6 March 2010

Methane is like the radical wing of the carbon cycle, in today’s atmosphere a stronger greenhouse gas per molecule than CO2, and an atmospheric concentration that can change more quickly than CO2 can. There has been a lot of press coverage of a new paper in Science this week called “Extensive methane venting to the atmosphere from sediments of the East Siberian Arctic Shelf”, which comes on the heels of a handful of interrelated methane papers in the last year or so. Is now the time to get frightened?

No. CO2 is plenty to be frightened of, while methane is frosting on the cake. Imagine you are in a Toyota on the highway at 60 miles per hour approaching stopped traffic, and you find that the brake pedal is broken. This is CO2. Then you figure out that the accelerator has also jammed, so that by the time you hit the truck in front of you, you will be going 90 miles per hour instead of 60. This is methane. Is now the time to get worried? No, you should already have been worried by the broken brake pedal. Methane sells newspapers, but it’s not the big story, nor does it look to be a game changer to the big story, which is CO2.

For some background on methane hydrates we can refer you here. This weeks’ Science paper is by Shakhova et al, a follow on to a 2005 GRL paper. The observation in 2005 was elevated concentrations of methane in ocean waters on the Siberian shelf, presumably driven by outgassing from the sediments and driving excess methane to the atmosphere. The new paper adds observations of methane spikes in the air over the water, confirming the methane’s escape from the water column, instead of it being oxidized to CO2 in the water, for example. The new data enable the methane flux from this region to the atmosphere to be quantified, and they find that this region rivals the methane flux from the whole rest of the ocean.

. March 12, 2010 at 10:05 am

China To Tap Combustible Ice As New Energy Source

“Huge reserves of “combustible ice” — frozen methane and water, have been discovered in the tundra of the Qinghai-Tibet Plateau in China. Estimates show that there is enough combustible ice to provide 90 years worth of energy for China. Burning the combustible ice may be a far better alternative than letting it just melt, releasing tons of methane into the air.”

. March 17, 2010 at 10:15 am

Methane May Be Building Under Antarctic Ice

* By Alexandra Witze, Science News Email Author
* March 16, 2010
* 3:39 pm
* Categories: Earth Science

BALTIMORE — Microbes living under ice sheets in Antarctica and Greenland could be churning out large quantities of the greenhouse gas methane, a new study suggests.

In recent years scientists have learned that liquid water lurks under much of Antarctica’s massive ice sheet, and so, they say, the potential microbial habitat in this watery world is huge. If the methane produced by the bacteria gets trapped beneath the ice and builds up over long periods of time — a possibility that is far from certain — it could mean that as ice sheets melt under warmer temperatures, they would release large amounts of heat-trapping methane gas.

Jemma Wadham, a geochemist at the University of Bristol in England, described the little-known role of methane-making microbes, called methanogens, below ice sheets on March 15 at an American Geophysical Union conference on Antarctic lakes.

Her team took samples from one site in Antarctica, the Lower Wright glacier, and one in Greenland, the Russell glacier. Trapped within the ice were high concentrations of methane, Wadham said, as well as methanogens themselves — up to 10 million cells per gram in the Antarctic sample and 100,000 cells per gram in Greenland. That’s comparable to the concentration of methanogens found in deep-ocean sediments, she said. The species of microbes were also similar to those found in other polar environments, such as Arctic peat or tundra.

. April 7, 2010 at 11:59 am

“Crucially, the period of plummeting coincides with a phenomenon called the late Triassic fern spike. This marks precisely—to within a few thousand years—the point of mass extinction on the land. What is believed to have happened is that something killed all the forests and with them the animals that depended on them. Freed from the competition for light (because the shade from the trees had gone), ferns flourished (their spores are ubiquitous in the rocks). Previous work has suggested that the oceans also became acidic at this time. Shelled creatures, whose calcium-carbonate-rich armour tends to dissolve in acid, suddenly became rare.

Put it all together and the probable course of events was this. The initial volcanism as North America split from Europe released carbon dioxide from deep inside the Earth. That produced a greenhouse effect which, in turn, melted seabed structures known as methane clathrates, which trap that gas in ice. This caused a massive release of 12C-rich methane into the atmosphere, explaining the initial drop in 13C concentrations. The methane, being a much more potent greenhouse gas than carbon dioxide, exacerbated things, while the carbon dioxide acidified the oceans, killing most of the animal shellmakers and fertilising the photosynthesis of planktonic plants. The subsequent plankton bloom sucked up the 12C and the isotope ratio veered off in the opposite direction.

The greenhouse warming and the acid rain also did for the forests and many of the reptiles. Only once things had settled down could the survivors regroup. New species of trees took over. The forests grew back. And a bunch of hitherto not-so-terrible lizards began their long march.”

. October 25, 2010 at 4:22 pm

As the permafrost warms, chances increase that pools of carbon previously trapped in the frozen permafrost will be released. Much more ominous will be the release of methane in the warming permafrost, since methane is a much more powerful greenhouse gas than carbon dioxide.

In other words, there are accelerating warming trends that feed into others that have been confirmed by scientists during the International Polar Year. To wit, more water instead of ice means more reflected sunlight, which, in turn, contributes to warming, which then causes more melting ice, and so on. To wit, more warming of permafrost changes patterns of animal and insect behaviour, and releases more greenhouse gases into the atmosphere. These gases, in turn, produce more warming. The scientists confirmed that the permafrost melt accelerates, in turn, when sea ice disappears and is replaced by open water.

Peer reviewed science! July 14, 2011 at 9:43 pm

Shakhova,N., Semiletov,I., Salyuk,A. et al. 2010.Extensive methane venting to the atmosphere from sediments of the East Siberian Arctic Shelf. Science 327:1246-1250: Heimann,M. 2010. How stable is the methane cycle? Science 327:1211-1212.

Eastern Siberian Arctic Shelf waters show evidence of significant escape to the atmosphere of old methane from ocean sediments. This implies another important positive climate system feedback that is as yet not included in model projections for future climates.

Methane stored within frozen permafrost on land and beneath the ocean floor is one of the wild cards in predicting future climate change since there is a risk that warmer climates could trigger the rapid release of large volumes of such methane. This would significantly enhance the change in climate currently projected by climate models. Analysis of observational data from the East Siberian Arctic Shelf region suggests that some release of methane may already be happening. The analyses of more than 5000 observations at many different locations over the region indicate that 80% of the bottom waters in this part of the Arctic Ocean are supersaturated with methane. Since average water depth in the region is only about 45 meters, much of the methane makes its way to the surface before being oxidized, resulting in 50% of surface waters also being supersaturated with methane. The net annual flux of methane from these waters into the atmosphere, both through diffusion from the surface and through bubbles rising directly from the bottom, is estimated to be about 8 Mt of C. The authors note that this is similar in magnitude to past estimates for total methane emissions from all global ocean surfaces. They also note that although the oceanic methane flux needs revision, their results do not drastically alter the contemporary global methane budget. However, this feedback should be added as an important feedback within earth system models.

Summary courtesy of Environment Canada

Peer reviewed science! July 14, 2011 at 9:46 pm

Archer, D., B. Buffett and V. Brovkin, 2009, Ocean hydrates as a slow tipping point in the global carbon cycle, PNAS, 106 (49), 20596-20601.

The ocean methane hydrate reservoir can be considered a very slow but irreversible tipping point in the Earth’s carbon cycle. The warming effect potentially caused by methane release from this source is likely to be very gradual and of moderate magnitude, but it would last for millennia.

Archer et al. simulate the spatial distribution of ocean methane hydrates and assess their sensitivity to changing climate. They estimate the current total inventory of methane in ocean hydrates is between 1600-2000 Pg of C. When the sediment column warms and hydrates melt, methane bubbles are produced. If the volume of these methane bubbles exceeds a critical value, the sediment column releases methane. A critical question for the future is how much methane from melting hydrates will potentially escape from the seafloor to reach the ocean or the atmosphere. The authors find that, in response to a 3°C ocean warming and assuming a 10% critical bubble fraction for gas escape, only 2% of the methane inventory (about 30 Pg of C) would potentially escape. However, if the critical bubble fraction is 2.5%, about 50% of the methane (940 Pg of C) could escape. When the hydrate model was embedded in a global climate model forced by two fossil fuel CO2 emission scenarios (1000 Pg of C and 5000 Pg of C) they found that methane is released over a time period of several thousand years. Even for high methane emission responses, the atmosphere only warms by about 0.4-0.5°C. Thus, the potential warming effect of melting hydrates on the atmosphere would be quite moderate and would take millennia to manifest. However, the induced warming was shown to persist for at least 10-kyr.

Summary courtesy of Environment Canada

. August 5, 2011 at 4:22 pm

By analysing the isotopic composition of hydrocarbon molecules from plant waxes of the period, he found what looks like a spike in the amount of recently non-biological carbon (which has a distinctive ratio of light isotopes to heavy ones), lasting between 10,000 and 20,000 years. He thinks the liberation of methane stored at the bottom of the ocean in structures called clathrates is the most likely culprit. The alternative, that the carbon came from the volcanoes, is unlikely because the spike is much shorter than the period of volcanic activity. Methane is a greenhouse gas far stronger than carbon dioxide, so the consequence would have been a rapid warming of the climate—a phenomenon that the rocks suggest did actually happen.

This is not the first time a methane burp has been blamed for an extinction. Though the Cretaceous asteroid cleared the stage, mammals did not really get going until 10m years later, in the Eocene epoch. The preceding Palaeocene epoch was also brought to an end, the rocks suggest, by a sudden release of methane.

The burp could, of course, have been provoked by the eruptions, so the volcanoes are not off the hook completely. But, for those of a nervous disposition, the tying of an ancient greenhouse warming to an ancient mass extinction might suggest lessons for the future.

. November 30, 2011 at 10:09 pm

As the Arctic warms, greenhouse gases will be released from thawing permafrost faster and at significantly higher levels than previous estimates, according to survey results from 41 international scientists published in the Nov. 30 issue of the journal Nature. Permafrost thaw will release approximately the same amount of carbon as deforestation, say the authors, but the effect on climate will be 2.5 times bigger because emissions include methane, which has a greater effect on warming than carbon dioxide.

The survey, led by University of Florida researcher Edward Schuur and University of Alaska Fairbanks graduate student Benjamin Abbott, asked climate experts what percentage of the surface permafrost is likely to thaw, how much carbon will be released and how much of that carbon will be methane. The authors estimate that the amount of carbon released by 2100 will be 1.7 to 5.2 times larger than reported in recent modeling studies, which used a similar warming scenario.

peer reviewed science November 30, 2011 at 10:12 pm

Climate change: High risk of permafrost thaw

Edward A. G. Schuur
Benjamin Abbott

Nature
480,
32–33
(01 December 2011)
doi:10.1038/480032a

Published online
30 November 2011

Northern soils will release huge amounts of carbon in a warmer world, say Edward A. G. Schuur, Benjamin Abbott and the Permafrost Carbon Network.

. January 11, 2012 at 6:58 pm

An Arctic methane worst-case scenario

Or, trying to “correct” for the different lifetimes of the gases using Global Warming Potentials, over a 100-year time horizon (which still way under-represents the lifetime of the CO2), you get that the methane would be equivalent to increasing CO2 to about 500 ppm, lower than 750 because the CO2 forcing lasts longer than the methane, which the GWP calculation tries in its own myopic way to account for.

But the methane worst case does not suddenly spell the extinction of human life on Earth. It does not lead to a runaway greenhouse. The worst-case methane scenario stands comparable to what CO2 can do. What CO2 will do, under business-as-usual, not in a wild blow-the-doors-off unpleasant surprise, but just in the absence of any pleasant surprises (like emission controls). At worst comparable to CO2 except that CO2 lasts essentially forever.

. August 24, 2012 at 3:43 pm

The worry that needs to be taken most seriously is climate change itself. The impact of the melting Arctic may have a calamitous effect on the planet. It is likely to disrupt oceanic circulation—the mixing of warm tropical and cold polar waters, of which the Gulf Stream is a part—and thawing permafrost will lead to the emission of masses of carbon dioxide and methane, and thus further warming. It is also raising sea levels. The Greenland ice sheet has recently shed around 200 gigatonnes of ice a year, a fourfold increase on a decade ago. If the warming continues, it could eventually disintegrate, raising the sea level by seven metres. Many of the world’s biggest cities would be inundated long before that happened.

. August 26, 2012 at 12:58 pm

The land masses that encircle the Arctic also prevent the polar oceans revolving around it as they do around Antarctica. Instead they surge, north-south, between the Arctic land masses in a gigantic exchange of cold and warm water: the Pacific pours through the Bering Strait, between Siberia and Alaska, and the Atlantic through the Fram Strait, between Greenland and Norway’s Svalbard archipelago.

That keeps the average annual temperature for the high Arctic (the northernmost fringes of land and the sea beyond) at a relatively sultry -15°C; much of the rest is close to melting-point for much of the year. Even modest warming can therefore have a dramatic effect on the region’s ecosystems. The Antarctic is also warming, but with an average annual temperature of -57°C it will take more than a few hot summers for this to become obvious.

. August 26, 2012 at 12:59 pm

Another concern, that thawing Arctic permafrost could release vast quantities of carbon dioxide and methane, looms larger. That, too, has happened before, around 55m years ago, leading to a global temperature increase of 5°C in a few thousand years.

. August 26, 2012 at 1:02 pm

Roughly a quarter of the northern hemisphere, including most of the Arctic land, is covered by this layer of frozen rock, soil and organic carbon. Formed over millennia, it varies in depth from a few centimetres to up to 1,500 metres in Siberia. Much of the Arctic’s shallow continental shelf is also covered by permafrost. According to an estimate made in 2009, terrestrial permafrost holds about 1.7 trillion tonnes of carbon, roughly twice as much as the atmosphere. By another estimate subsea permafrost stores an additional 0.5 trillion tonnes. And underlying it there may be another 0.8 trillion tonnes in the form of methane hydrates, an icy white material discovered in the 1960s.

Though tricky to get at, methane hydrates could be a massive energy source. Globally they are estimated to contain more energy than all known deposits of fossil fuels. Yet if even a small portion of the methane contained in them were to be abruptly emitted, the warming effect could be catastrophic. Methane is a short-lived greenhouse gas—it stays in the atmosphere for 6-10 years before being oxidised—but it is 25 times more efficient than carbon dioxide at trapping heat. And no one is sure how stable the hydrates are.

Given the scale of these risks, it is extraordinary how little research has been done on permafrost. “There are a lot of white spots in our knowledge,” admits Leonid Yurganov, a permafrost expert at the University of Maryland—Baltimore County. But a lot has recently been learned, which suggests that an explosive methane release is very unlikely. Ice cores going back 800,000 years show no trace of such an event. Nonetheless, the release of permafrost or subsea carbon could be gradual and still cause a lot of warming, and that does seem likely.

. September 17, 2012 at 11:42 am

Permafrost is permanently frozen soil, sediment or rock. It’s estimated that about 18.8 million sq km of northern soils hold about 1,700 billion tonnes of organic carbon, or frozen compost—the remains of plants and animals that have accumulated over thousands of years. That’s about four times more than all the carbon emitted by human activity in modern times, and twice as much than is currently in the atmosphere.

The new study predicts that by the end of this century, permafrost could release between 68 and 508 billion additional tonnes of carbon into the atmosphere, raising global temperatures by an average of 0.4 to 0.8°C. When combined with observed warming since pre-industrial times and committed warming in response to existing greenhouse gas levels, this suggests the planet is heading toward a 1.8 to 2.3°C rise in temperature—even if we start reducing emissions immediately.

. November 13, 2012 at 9:48 pm

Tapping what could be world’s next big energy source threatens to ‘unleash the monster’

Work is underway to extract methane trapped in the Alaskan ice, but environmentalists fear this potent greenhouse gas could stoke a global warming nightmare.

. April 14, 2014 at 7:28 pm

The climate is warming in the arctic at twice the rate of the rest of the globe creating a longer growing season and increased plant growth, which captures atmospheric carbon, and thawing permafrost, which releases carbon into the atmosphere. Woods Hole Research Center (WHRC) Assistant Scientist Sue Natali and colleagues engineered first-of-a-kind warming experiments in the field to determine net gains or losses in carbon emissions. The study entitled “Permafrost degradation stimulates carbon loss from experimentally warmed tundra,” published in the journal Ecology found that growing season gains do not offset carbon emissions from permafrost thaw. According to Dr. Natali, “Our results show that while permafrost degradation increased carbon uptake during the growing season, in line with decadal trends of ‘greening’ tundra, warming and permafrost thaw also enhanced winter respiration, which doubled annual carbon losses.”

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