The Arctic Methane Monster
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 catastrophic any time soon.
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) |
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 destabilized. 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. According to older estimates, the total amount of methane 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.
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:
Events in which most, if not virtually all methane that escaped from the seabed did enter the atmosphere have been studied in 2002 and published in 2006, as reported at:
http://www.ia.ucsb.edu/pa/display.aspx?pkey=1482
and at:
http://onlinelibrary.wiley.com/doi/10.1029/2005GB002668/abstract
Below, a screenshot from an interview of John Mason with Natalia Shakhova, published at:
http://www.skepticalscience.com/arctic-methane-outgassing-e-siberian-shelf-part2.html
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:
http://methane-hydrates.blogspot.com/2012/03/large-areas-of-open-ocean-starved-of.html
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 flowed 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:
http://methane-hydrates.blogspot.com/2013/04/methane-hydrates.html
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 ] |
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 ] |
“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?
Related
- Arctic Methane Monster
http://arctic-news.blogspot.com/2013/09/arctic-methane-monster.html
- Methane over deep waters of Arctic Ocean
http://arctic-news.blogspot.com/2013/10/methane-over-deep-waters-of-arctic-ocean.html
- Methane hydrate myths
http://methane-hydrates.blogspot.com/p/myths.html
- Methane hydrates
http://methane-hydrates.blogspot.com/2013/04/methane-hydrates.html
- Methane release caused by earthquakes
http://arctic-news.blogspot.com/2013/09/methane-release-caused-by-earthquakes.html
- Earthquake hits Laptev Sea
http://arctic-news.blogspot.com/2013/09/earthquake-hits-laptev-sea.html
- North Hole
http://arctic-news.blogspot.com/2013/09/north-hole.html
- Seismic activity, by Malcolm Light and Sam Carana (2011)
Arctic-news.blogspot.com/p/seismic-activity.html
- Thermal expansion of the Earth’s crust necessitates geoengineering (2011)
Arctic-news.blogspot.com/p/thermal-expansion.html
Post by Sam Carana.
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