Tuesday, November 19, 2013

Me, or your lying eyes?

Walk with me, talk with me
Walk with me, talk with me
Natalia, Natalia, Natalia

 Van Morrison 


          Is Abrupt Climate Change due to methane releases from the Arctic something we should be concerned about?     Not according to the IPCC.     Yet, according to this article :  Climate change crisis intensifies: 'Methane levels are going through the roof,  recent readings are very high.
The latest levels published today have recorded methane readings "well over 2600 ppb at multiple altitudes, as illustrated by the image." (see slideshow to the left of this article)
What is considered a "normal" release of methane? According to Dr. James Hansen, an American adjunct professor in the Department of Earth and Environmental Sciences at Columbia University, 1250 ppb is a livable level. To put that into perspective, the current number of methane being released is twice that level.
       I generally like to go with IPCC.  However, they have been known to be very conservative.         

       I get the impression it all comes down t Dr Natalia Sahkhova,  who is up there studying where no one else is.   She's getting some disturbing readings. And no one really has a good explanation.  They don't fit with the models.   So they either don't accept the measuerments, or chalk it up to some local anomaly

Here's what Prof Peter Wadhams says:  in response to criticism of his paper in Nature, which relied on Sahkova's data

"In support of its skepticism about methane emissions the article quoted authors who wrote before the enormous retreat of summer Arctic sea ice and its oceanographic effects became so evident. The mechanism which is causing the observed mass of rising methane plumes in the East Siberian Sea is itself unprecedented and the scientists who dismissed the idea of extensive methane release in earlier research were simply not aware of the new mechanism that is causing it.
"What is happening is that the summer sea ice now retreats so far, and for so long each summer, that there is a substantial ice-free season over the Siberian shelf, sufficient for solar irradiance to warm the surface water by a significant amount – up to 7C according to satellite data. That warming extends the 50 m or so to the seabed because we are dealing with only a polar surface water layer here (over the shelves the Arctic Ocean structure is one-layer rather than three layers)  and the surface warming is mixed down by wave-induced mixing because the extensive open water permits large fetches.  So long as some ice persisted on the shelf, the water mass was held to about 0C in summer because any further heat content in the water column was used for melting the ice underside. But once the ice disappears, as it has done, the temperature of the water can rise significantly, and the heat content reaching the seabed can melt the frozen sediments at a rate that was never before possible.
- See more at: here

    Here's a couple of articles for your consideration.  Here's a  Video : Last Hours  ( h/t LarryT)

The methane emergency-denying IPCC

Never mind the evidence - the problem does not exist, says the science-by- committee IPCC

Just do NOT tell them the monster exists

The Arctic Methane Monster
7 October, 2013

As discussed in a previous post, the IPCC appears to be acting as if there was a carbon budget to divide among countries, whereas in reality there is a huge carbon debt to our children, while the situation could become catastropic any time soon.

Indeed, carbon dioxide is not the only greenhouse gas and the Arctic methane monster is threatening to disrupt the cosy lifetyle of those who want to keep selling parts of such non-existing carbon budgets.

So, who do you think the IPCC has been listening to, to reach a conclusion after six years of analysis? Experts or snake oil sellers? The cartoon may give you a hint, but why don't you make up your own mind by going over the IPCC statements and comments below.

Abrupt Climate Change

The IPCC recently issued AR5 documents that included a discussion of Abrupt Climate Change.

from: IPCC AR5 Working Group 1 Technical Summary (final draft)

The IPCC gives some examples:

Yes, methane release from clathrates sounds scary.

If there is little consensus on the likelyhood, then surely some experts do believe it is likely. Yet, the IPCC somehow reaches the following conclusion, and does so with high confidence:

Unlikely? What was the basis for this IPCC conclusion? 

This seems like a conclusion that can only have been reached after a robust analysis of all the evidence. So, how did the IPCC reach this conclusion, given that it did so with such high confidence?

Let's have a look. The above conclusion is preceeded by this statement:

OK, that means clathrates will increasingly become destablilized. The IPCC then adds an argument why this would not result in abrupt climate change this century. 

Sure, but that's just one rather insignificant negative feedback, compared to the many more significant positive feedbacks, such as melting causing isostatic rebound that can contribute to the occurrence of earthquakes and landslides, in turn triggering methane release. Yet, without even mentioning these positive feedbacks, the paragraph then jumps to the following conclusion:

If these initial estimates are not insignificant and if it's all rather difficult to formally assess, how then is it possible that the IPCC reached its end-conclusion with such high confidence? Moreover, was there any basis for these "initial estimates"? Perhaps there's more elsewhere in the IPCC documents. Here's another paragraph that preceeded the above.

All this expresses is low confidence in existing modeling and lack of understanding of the various processes. Again, how then is it possible that the IPCC reached its conclusion with such high confidence?

How much methane is currently released from hydrates?

On this, the IPCC says:

OK, so things could become scary. And sure, there are no large abrupt releases taking place now, but that doesn't mean there's not going to be any in future. In case of gradual processes, it makes sense to base projections on historic releases. In case of abrupt releases, however, current releases should not be the basis for reaching a conclusion with high confidence.

So, was the work of Dr. Natalia Shakhova perhaps used as the basis for these estimates? Read on!

How much methane is stored under the Arctic Ocean?

How much methane is present in sediments under the seabed of the Arctic Ocean, in the form of free gas and hydrates? On this, the IPCC says in FAQ6:

That doesn't seem to reflect the estimates of Dr. Natalia Shakhova. The total 
amount of methane currently in the atmosphere is about 5 Gt. Saying that more than 50 Gt of methane could be stored in hydrates the Arctic seems deceptive and appears to be seriously downplaying a very dangerous situation.

Natalia Shakhova et al. in 2010 estimated the accumulated potential for the East Siberian Arctic Shelf (ESAS) region alone (image on the right) as follows:
  • organic carbon in permafrost of about 500 Gt
  • about 1000 Gt in hydrate deposits
  • about 700 Gt in free gas beneath the gas hydrate stability zone.
Back in 2008, Natalia Shakhova et al. considered release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time. Did the IPCC perhaps misread the figures, mistaking the part of the methane that is ready for abrupt release for the total amount of methane in the Arctic?

How long could it take for large amounts of methane to reach the atmosphere?

How long could it take for large amounts to reach the atmosphere? On this, the IPCC says in FAQ6, in the same and the next paragraph:

Below, a screenshot from an interview of John Mason with Natalia Shakhova, published at:

In conclusion, Dr Natalia Shakhova also rejects the idea that methane release from hydrates always takes place gradually, over a long time. Especially in the Arctic, there's a huge danger of abrupt release, given the accelerated warming that takes place in the Arctic, given the huge amounts of methane stored in sediments in the form of free gas and methane, given the presence of a tectonic fault line, etc, etc.

Once released, methane won't get broken down easily in the Arctic Ocean, as this requires the presence of bacteria that can oxidize the methane, as well as free oxygen in the water. Once depleted, oxygen isn't quickly replenished in the Arctic Ocean. Lack of bacteria and depletion of oxygen in the waters of the Arctic Ocean could prevent oxidation of methane rising up in the waters, as described at:

In the Arctic, low temperatures mean there are less bacteria that need more time to break down the methane. In other places, currents may bring bacteria back to the location of the methane plume repeatedly. In the Arctic, many currents are long, so once bacteria have flow away from the location of the plume, they could be driven out of the Arctic Ocean or may return only after a long time, i.e. too long to survive in Arctic waters which are cold and often ice-covered, so a lot of time little or no sunshine penetrates the waters.

In the Arctic, the danger is much larger that methane releases will overwhelm the capacity of bacteria to break it down in the water. In case of large abrupt releases in the Arctic, the danger is that much of the methane will reach the atmosphere unaffected and remain there for a long time, due to the Jet Stream and the low levels of hydroxyl in the Arctic atmosphere, as further described at:

BTW, how did all this methane manage to reach the atmosphere over the Arctic Ocean? 

Methane levels over the Arcic Ocean appear to be rising, as illustrated by the combination of images below, showing methane levels over five years (2009 on the left, to 2013 on the right), each time for the same period (January 21-31) - images by Dr. Leonid Yurganov.

[ Click on image to enlarge - from: Dramatic increase in methane in the Arctic in January 2013 ]

If the IPCC was right, how then was it possible methane levels to rise so sharply and abruptly. How was it possible for large amounts of methane to be present over the deep waters of the Arctic Ocean, as discussed at:http://arctic-news.blogspot.com/2013/10/methane-over-deep-waters-of-arctic-ocean.html

[ How did this methane get there? - click on image to enlarge - see also: Methane over deep waters of Arctic Ocean ]

There is a wealth of evidence from scientists such as Igor Semiletov and Natalia Shakhova who have - year after year - been taking measurements in the East Siberian Arctic Shelf, complete with first-hand reports that methane plumes have been detected.

"We've found continuous, powerful and impressive seeping structures more than 1,000 metres in diameter. In a very small area, less than 10,000 square miles, we have counted more than 100 fountains, or torch-like structures, bubbling through the water column and injected directly into the atmosphere from the seabed," Dr Semiletov said, "We carried out checks at about 115 stationary points and discovered methane fields of a fantastic scale - I think on a scale not seen before. Some of the plumes were a kilometre or more wide and the emissions went directly into the atmosphere - the concentration was a hundred times higher than normal."  -  Vast methane 'plumes' seen in Arctic ocean as sea ice retreats, by Steve Connor in The Independent, December 13, 2011.

The image below shows a cluster of methane plumes, over one km in diameter, that appeared in the Laptev Sea end September 2011. The image is part of a paper on the unfolding "Methane Catastrophe".

Of course, we all wished that we're wrong about this terrifying Arctic methane threat, but the precautionary principle demands a thorough investigation of observations that appear to be at odds with wishful thinking, especially when the stakes are so high. So, IPCC, where's the evidence?


How much should you worry about an Arctic methane bomb?

planet-earth-bomb.jpgIt was a stunning figure: $60 trillion.
Such could be the cost, according to a recent commentary [PDF] in the journal Nature, of “the release of methane from thawing permafrost beneath the East Siberian Sea, off northern Russia … a figure comparable to the size of the world economy in 2012.” More specifically, the paper described a scenario in which rapid Arctic warming and sea ice retreat lead to a pulse of undersea methane being released into the atmosphere. How much methane? The paper modeled a release of 50 gigatons of this hard-hitting greenhouse gas (a gigaton is equal to a billion metric tons) between 2015 and 2025. This, in turn, would trigger still more warming and gargantuan damage and adaptation costs.
The $60 trillion figure went everywhere, and no wonder. It’s jaw-dropping. To provide some perspective, 50 gigatons is 10 times as much methane as currently exists in the atmosphere. Atmospheric methane levels have more than doubled since the industrial revolution, but this would amount to a much sharper increase in a dramatically shorter time frame.
According to the Nature commentary, that methane “is likely to be emitted as the seabed warms, either steadily over 50 years or suddenly.” Such are the scientific assumptions behind the paper’s economic analysis. But are those assumptions realistic — and could that much methane really be released suddenly from the Arctic?
A number of prominent scientists and methane experts interviewed for this article voiced strong skepticism about the Nature paper. “The scenario they used is so unlikely as to be completely pointless talking about,” says Gavin Schmidt, a noted climate researcher at the NASA Goddard Institute for Space Studies in New York.
Schmidt is hardly the only skeptic. “I don’t have any problem with 50 gigatons, but they’ve got the time scale all wrong,” adds David Archer, a geoscientist and expert on methane at the University of Chicago. “I would envision something like that coming out, you know, over the centuries.”
Still, the Nature paper is the most prominent airing yet of concerns that a climate catastrophe could be brought on by the release of Arctic methane that is currently frozen in subsea deposits — concerns that seem to be mounting in lockstep with the dramatic warming of the Arctic. That’s why it’s important to put these fears into context and try to determine just how much weight they ought to be accorded.
Methane on ice
Let’s start with some basics on methane — CH4 — a greenhouse gas that reaches the atmosphere from sources as diverse as wetlands, gas drilling, and cow burps. Compared with carbon dioxide, methane is kind of like the boxer who punches himself out in the early rounds, whereas carbon dioxide goes the distance and wins by TKO. Pound for pound, methane causes some 25 times as much global warming[PDF] as carbon dioxide does. But it only remains in the atmosphere for about nine years, on average, before chemical processes break it down. Carbon dioxide, in contrast, has a far longer atmospheric residence time.
What this means is that methane is most worrisome if a lot of it gets into the atmosphere over a relatively short time period — precisely the scenario contemplated by the Nature paper. So could that happen?
The answer depends on a complicated and uncertainty-laden issue — the stability of frozen deposits of subsea methane in the Arctic region. Frankly, it’s hard to imagine something harder to study: We’re talking about deposits residing not only beneath one of the world’s most remote and inaccessible oceans, but also beneath the sea floor itself.
Much of the world’s methane is concentrated in the form of so-called gas “hydrates,” icelike solids that form from methane and water at cold temperatures and high pressures, e.g., deep beneath the ocean floor. According to the U.S. Geological Survey, the total global carbon content of such methane hydrates is estimated to equal some 1,800 gigatons (to be sure, there is considerable uncertainty about this estimate).
Cross-section showing the location of methane hydrates, which are most vulnerable to dissolution in regions 2 and 3.U.S. Geological SurveyCross-section showing the location of methane hydrates, which are most vulnerable to dissolution in regions 2 and 3.
One thousand eight hundred gigatons would create a climate catastrophe if it were all to be suddenly released, but the vast majority of subsea methane is under deep water, and quite stable. Only a relatively small fraction of global methane hydrates are at issue in the Nature paper, and this methane is in a very peculiar situation: It is frozen in the subsea permafrost of relatively shallow continental shelves in the Arctic region. This frozen sediment was once coastline, but was submerged as oceans rose following the last Ice Age. And now, it is being bathed in warmer waters due to the warming of the Arctic.
So how much should we worry that these particular methane hydrates might melt, releasing gas that would then travel through both sediment and seawater to reach the atmosphere? That’s where the scientific debate begins — over both how much methane falls into this category, and how vulnerable it is to the warming that is now gripping the Arctic region.
Peering beneath the East Siberian Sea
The methane disaster concerns gained major prominence with a2010 paper in Science by University of Alaska-Fairbanks researcher Natalia Shakhova and her colleagues, who examined methane emissions in a very remote area of the Arctic, the East Siberian Sea north of Russia. The continental shelf underlying this ocean is more than 2 million square kilometers (1.2 million square miles) in size, and its subsea permafrost lies only about 50 meters below the sea surface. Traveling to the remote region in Russian ice-breakers, Shakhova’s team sampled water content and air content at the sea surface repeatedly, over a series of years. They found high concentrations of methane in the water — “50 percent of surface waters are supersaturated with methane,” the paper reported — and some of the gas was also venting from the water into the atmosphere.
East_Siberian_Sea_mapWikimedia Commons
Although the Science paper did not contain the figure, it seems clear that Shakhova is the source for the idea that a 50-gigaton release of methane could occur in a short time frame. Or as she put it in a2008 abstract [PDF], “[W]e consider release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time,” adding that this could lead to “catastrophic greenhouse warming.” The Nature paper cited another 2010 paperby Shakhova and her colleagues in the journal Doklady Earth Sciences, which uses the 50-gigaton figure in discussing possible methane emission scenarios.
Shakhova did not respond to several requests for comment for this article; her automatic email response said she was out doing fieldwork. But Peter Wadhams, the Cambridge physicist who is a coauthor of the Nature paper, said that his work relied on that of Shakhova and her team because “they’ve done the most work there, working there every year, doing field observations … we would rather base it on the estimates of the people actually working there, rather than the people who aren’t working there.” Here is a video of Shakhova discussing her research:
The trouble is that at this point, many other scientists don’t accept that work — or rather, don’t agree about its implications. None seem to dispute the actual measurements taken by Shakhova and her team, but as soon as the Science paper came out, a group of researchers questioned the idea that there was any cause for alarm. “A newly discovered [methane] source is not necessarily a changing source, much less a source that is changing in response to Arctic warming,” they wrote. The implication is that perhaps methane has always been in the water at such levels, without methane hydrates having been disturbed — rather, the methane may be from another source. According to one 2011 study, for instance, the observed methane probably came not from hydrates, but simply from “the permafrost’s still adjusting to its new aquatic conditions, even after 8,000 years.” The hydrates, in contrast, are thought to be much deeper below the sea surface, due to basic physical constraints on their formation and stability. According to the U.S. Geological Survey, “in permafrost areas, methane hydrate is not stable until about 225 m [738 feet] depth.”
Indeed, according to Ed Dlugokencky, who monitors global atmospheric methane levels at the National Oceanic and Atmospheric Administration, “so far, there has not been a significant increase in methane emissions in the Arctic.” In other words, if methane is really starting to vent into the air in large quantities, Dlugokencky says he isn’t seeing it.
A debate over hydrate depth
And that’s just the first reason that many scientists are skeptical. According to Carolyn Ruppel, who heads the Gas Hydrates Project at the U.S. Geological Survey, there just isn’t that much vulnerable methane in submerged permafrost to begin with. “We think very little hydrate on this planet is associated with permafrost, either subsea or terrestrial,” she says. Inspired in part by the Shakhova research, the USGS undertook to study the continental shelves of the Beaufort Sea, off Alaska and Canada. “We set out to test this idea that all of the Arctic shelves were going to have high methane emissions,” she says. “And at least for the U.S. Beaufort shelf, we’re not seeing them.”
Ruppel acknowledges that due to Arctic warming, more methane is going to be released, much of it from permafrost on land. But, she continues, “I would say one of the least likely sources is methane gas hydrates. You are limited by the laws of physics,” she adds — noting that the beginning of the zone of stability for these hydrates is some 220 meters (722 feet) deep. That’s a recurrent refrain among skeptics — they say hydrates just can’t form above a certain depth, and warming can’t penetrate such a depth very quickly. “You’ve got to go from the sea floor of 50 meters depth, down to 200 meters where the hydrate is,” explains the University of Chicago’s David Archer. “So that just takes a long time.”
Moreover, even if subsea permafrost methane hydrates do thaw, the liberated gas still has to travel through layers of sediment just to get to the ocean floor. So how does that happen? “That’s kind of mysterious,” says Archer. Perhaps there will be open pathways for gas in some places, but perhaps there won’t. Archer also notes that there have been undersea explosions or landslides that release methane in bursts, but “those kinds of things seem like they would be relatively small compared to 50 gigatons, and they would happen sporadically in time over centuries; not everything blows up in a few years.”
Nonetheless, imagine that methane gas from melted hydrate makes it to the sea floor. It now exists as bubbles with, say, 50 meters (164 feet) to go before they reach the sea surface. Most of the bubbles won’t make it, say scientists: They’ll be dissolved in seawater, and then the methane will be broken down by microorganisms over a period of months. “If methane is in the ocean water column, most of it doesn’t get out,” explains Bill Reeburgh, a professor of earth system science at the University of California-Irvine who has spent his career studying methane. “Most of it is oxidized” by bacteria, which turn it into carbon dioxide and water, Reeburgh continues. “So all these stories about seeps, people seem to think the bubbles go straight to the atmosphere, and they don’t.”
In other words, while the waters of the East Siberian Sea may be full of dissolved methane, for many scientists that doesn’t prove that hydrates have been disturbed, or that the Arctic is starting to vent large amounts of methane from below the sea floor into the atmosphere. Not yet, anyway.
Nonetheless, Cambridge’s Peter Wadhams takes a different view. Of the critics, he says that “it comes to not believing that these scientists who are actually working there know what they’re talking about, which I would say is kind of insulting to them.” Wadhams also says that there is a new mechanism for methane hydrate release that the critics aren’t considering. The retreat of Arctic sea ice, he suggests, is allowing very intense warming of the waters above continental shelves. He adds that there are certain hydrates “detectable at 20 meters [66 feet]” below the sea floor, far shallower than normal. Wadhams calls these hydrates “Ice Age relics” that formed under very different conditions. Shakhova, too, has referred in the past to hydrates occurring at 20 meters depth, saying they have been “sampled in Siberia.”
Other scientists remain skeptical. David Archer says his simulations “never see hydrate stability” above 250 meters (820 feet).
So should you worry?
What is clear about this story, then, is that one group of scientists has articulated a set of concerns that a number of others just do not accept at this point. And no doubt this problem is exacerbated by the realities of methane hydrate research — it is extremely difficult (and costly) to take a scientific expedition to the East Siberian Sea, or for that matter, to conduct Arctic research in general. In this case, it appears that one research team, the one actually working in this area, has developed views distant from those of many other researchers.
So what should you do — and what should you think? Bear in mind that there are many good reasons to be skeptical of a methane disaster — it is hardly a matter of scientific consensus that this is a real concern. And that stands in stark contrast to the issue of climate change in general, an issue on which scientists are overwhelmingly aligned (and where the solution remains incredibly obvious: cutting carbon emissions).
As global warming proceeds, it is also important to step back and acknowledge that with the unprecedented warming of the Arctic, it would be surprising if there weren’t surprises. When we bring on warming this fast, we risk unpredictable consequences, whether with regard to methane or something else.
“It’s weird for me to be saying, ‘Oh, it could never happen.’ It’s always the wrong side of things when you’re talking about nature,” says David Archer of the Arctic methane catastrophe scenario. “But,” he adds, “nobody’s come up with a defendable way of it happening all at once.”
This story was produced by Mother Jones as part of the Climate Desk collaboration.
Chris Mooney is a science and political journalist, blogger, podcaster, experienced trainer of scientists in the art of communication, and the host of Climate Desk Live.

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