Saturday 16 August 2014

The Arctic methane emergency monster

The Keystone Pipeline, Arctic Methane Eruptions, and Why Human Fossil Fuel Burning Must Swiftly Halt

15 August, 2014


Human fossil fuel emissions heating the Earth’s airs, waters, and ice.


Since the 1880s, humans have emitted nearly 600 billion tons of carbon into the atmosphere. This vast emission has spiked atmospheric CO2 and CO2e (when all other heat trapping gasses are included) levels to above 400 parts per million and 481 parts per million respectively. According to climate sensitivity and paleoclimate science, these volumes are already enough to increase global temperatures by between 1.5 to 2 C this century and 3-4 C long term.

At the current carbon emissions rate of more than 10 billion tons each year and growing at around 2 percent, humans will have emitted a trillion tons of carbon by 2041. Under business as usual fossil fuel burning, more than 2.5 trillion tons of greenhouse gas trapping carbon will hit the atmosphere before the end of this century. It’s a terrible blow we will sorely want to avoid. And one we can only circumvent if we start working to radically curtail carbon emissions now.

Already, we can see instances of emissions-driven climate change and related harm. But what we see now is minor compared to what the future holds in store. We’ve warmed the Earth by more than 0.8 degrees Celsius since the 1880s, and if human emissions do not swiftly come to a halt, we could easily see warming of 4, 5, 7 C or more by the end of this century alone.



Probability of stabilizing below 2 C
(Probability of exceeding 2 C warming this Century [equilibrium climate sensitivity] given a certain level of human greenhouse gas forcing. Note that this study did not include feedbacks from Arctic carbon stores. Also note that current CO2 equivalent forcing without aerosols is around 481 CO2e and with the aerosol negative feedback is around 425 CO2e. Also note that equilibrium climate sensitivity is about half that implied by Earth Systems Sensitivity over the long term [many centuries]. For a final note, consider that the aerosol negative feedback is temporary. Image source: IPCC.)


What Does Warming Look Like If We Continue To Burn Fossil Fuels?

We talk about warming in terms of degrees Celsius and gigatons of carbon burned. But what does it all really mean?

Droughts rampaging through the lower to mid latitudes as the US, Southern Europe, India, the Middle East, Brazil, Australia, the Sahel and sections of China rapidly turn to desert.

Stratified oceans turning into extinction engines for fish and marine life, fresh water poisoning due to toxic algae blooms, oceans emitting increasing volumes of poisonous hydrogen sulfide gas into the air. Fires the likes of which we have never seen in the far north as the permafrost burns and methane leaks and explodes from the thawing earth. Floods raging from an atmosphere whose moisture cycling has increased by 30 percent or more Sea level rise rapid enough to swallow cities and coastlines over the course of decades.

Devastating storms emerging from the regions closest to large glacial melt events bordering Greenland and West Antarctica. And all around, more and more people migrating, trying to find a place that is not being gobbled up by desert, incessantly burning, ravaged by storms, flooded, or poisoned by toxic air and water.




Very Large Algae Bloom Barents
(Very large bloom of micro-organisms north of Scandinavia in Arctic waters on August 14, 2014. Arctic waters are rich in nutrients. As they warm and as the sea ice retreats, larger areas are freed for invasion by major blooms of algae and other microbes. Large enough blooms can rob the ocean of oxygen, produce harmful toxins, result in large fish kills, and in the end create dangerous bottom conditions favoring microbial hydrogen sulfide production. Image source: LANCE-MODIS.)


That’s the dark future we inch closer to with every 0.1 C degree of further warming, with each additional megaton of fossil fuel and industrial carbon hitting the atmosphere.

And it is in this context that we must judge our actions and those of our leaders in reducing or in failing to reduce a nightmare that now grows in intensity with each passing year. A nightmare we create and continue to contribute to each time we light a fossil fuel driven fire.

Quibbling over Keystone Carbon Emissions When Tar Sands is the Real Issue

50 billion tons. That’s the amount of extractable, burnable carbon that likely sits beneath what were once the green forests of Alberta and are now little more than a sprawling waste of smoking pits covering tens of square miles. It’s more than 8 percent of the carbon we’ve already dumped into the atmosphere and it’s a volume of carbon we simply cannot afford to burn.

1.7 million barrels of crude oil per day now comes out of a place that Tolkien would likely describe as a mechanized orc warren. Keystone would boost that total to 2.2 million barrels per day, enrich the pit owners, and lay the groundwork for an ever-more-rapid exploitation of this dangerous pile of atmospheric heat-venom.

This week, a recent study out of Stockholm’s Environment Institute found that the pipeline itself would result in at least 4 times the carbon emissions currently estimated by the US State Department. This, well-duh, assessment, came as pit mining cheerleaders such as the American Petroleum Institute and Canadian Industry groups marshaled yet another effort to ram the pipeline through and boost global carbon emissions all in one go.



IDL TIFF file
(Athabasca’s sprawling tar sands operation as seen from space in 2009. The brown ribbon cutting through center frame is the Athabasca river. Image source: NASA’s Earth Observatory.)



In the end, all fossil fuels are terrible, adding to the global nightmare described above. But tar sands are between 12 and 20 percent more carbon intensive than even regular oil, especially when burning of the, worse than coal, coke bi-product is taken into account.

Arctic Methane Explosions — A Result of Human Warming

On the other side of the Arctic from the smoking fossil fuel pits of Alberta, nature is in the process of excavating a new, and no less terrifying, kind of pit. For from the Siberian tundra this summer were discovered three gaping wounds in the earth. Black holes shaped by impressive charges of methane blasting up from beneath the thawing permafrost.

All around the holes were ejected material. A kind of reverse meteor strike or methane volcano in which frozen methane trapped in clathrate beneath the thawing permafrost warmed enough to destabilize. The thawed methane built up in pressure pockets 250 feet or more below ground. Eventually, the pressure became too great and the permafrost overburden erupted, ejecting both earth and methane into the air above.

Eyewitnesses described eruption scenes where the Earth at first began to smoke. The smoke continued to bleed from the ground. Then, there was a loud flash and bang. When the smoke cleared, the methane eruption craters were plainly visible — a rim of sloped and ejected earth surrounding a black, gun-barrel like structure tunneling deep into the ground.




Russia Siberia Crater
(One of three freakish craters caused by eruptions of methane from Siberia’s thawing tundra. Image source: Moscow Times.)


The Arctic permafrost alone contains about 1.5 trillion tons of carbon. And when it thaws, a portion of that carbon is bound to be released. It will be broken down by microbes and turned into methane in wet soil. In drier soil, it will form a peat like underburden that will slowly release CO2 by decay or, in more violent instances, by burning in one of the ever more powerful wildfires raging through the Arctic during the increasingly hot summers.

Beneath the icy permafrost layer are pockets of frozen methane in the form of clathrates. These structures are not included in the 1.5 trillion ton carbon estimate for permafrost. They are an addition of likely billions more tons of carbon. And, this year, we can now see a physical mechanism for their continued release — warming and thaw of the permafrost overburden.

The Human-Arctic Feedback Link: Why We Absolutely Must Stop Burning Fossil Fuels, And Swiftly

It is estimated that 1.5-2 degrees Celsius worth of global warming (5-8 C Arctic warming) is enough to thaw all the permafrost and eventually release a substantial portion of the carbon stored in and beneath it. For the Arctic warms much faster than the globe as a whole. In tundra regions, rates of warming over the past three decades have been 0.5 degrees Celsius per decade or more. In the region where the methane craters were discovered, recent temperatures at 5 degrees Celsius above average, during summer heatwaves in 2013 and 2014, have been reported.

As a result of past and current human greenhouse gas emissions, we have already locked in a substantial and significant rate of Arctic carbon emission feedback. And the speed of the Arctic carbon store release will likely determine how rapidly and whether other global carbon stores also respond.

A 2011 survey of 41 Arctic researchers found that rapidly reducing human greenhouse emissions would limit the volume of carbon feedback from the Arctic to 10% of the annual current human emission (or about 1 billion tons of carbon per year) by the end of the 21rst Century, but continue that emission for centuries to come (current Arctic carbon emissions are likely in the range of 30 million tons of methane and 100 million tons of CO2 each year). This is bad news. For we have already burned enough fossil fuel to keep warming on the trajectory to hit 1.5 to 2.5 C this century and 3-5 C or somewhat more long term — a bad result, and one that would likely require extensive human deployment of atmospheric carbon capture technologies. But it is far better than the alternative.

For continued fossil fuel burning would be enough to force a release of Arctic carbon stores equal to 35% or more of the human annual emission, or about 3.5 to 4 gigatons of carbon each year. By itself, this emission would easily represent a mini-runaway pushing the business as usual burning level of 800 ppm CO2 and 1,000 ppm CO2e by end century to 1,400 ppm CO2 + over the course of centuries and likely resulting in 4-7 C + warming this century and 12-14 C + worth of warming long term. A hothouse extinction event to rival or potentially exceed the worst seen in the geological record.

We simply must stop fossil fuel burning as it risks triggering ever greater carbon releases from stores around the globe and especially in the Arctic. In this way, stopping fossil fuel burning or failing to stop that burning is directly related to the ferocity and intensity of the Earth systems response we set off. And halting the Keystone Pipeline is a good approach to curtailing future carbon emission increases. A good start to a long, hard road ahead.

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