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scaddenp at 10:28 AM on 20 August 2014Global warming denial rears its ugly head around the world, in English
"Rarely have I seen a breakup of the argument into the basic science, the evidence, the likely impacts and the political and economic solution."
So what are the IPCC WG reports then? The political and economic solutions are harder because there is not a one-size-fits-all solution. Scientists are not economists either. Use whatever sits with your political values that will results in less emissions is the basic response. The WG3 report certainly lays it out.
The WG1 report does not fit into a media sound-bite and so it is inevitiable that discussion is fragmented. However, anyone actually wanting to be informed can always read the report. Shooting the messenger is more popular however.
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Wol at 10:23 AM on 20 August 2014Global warming denial rears its ugly head around the world, in English
Another problem is that the average man in the street nowadays has such limited education or interest in science (an I myself am a layman in this respect) that being told that the planet will warm by say two degrees evokes the response "so what? I like warmer weather".
That there is a fundamental difference between temperature and heat passes him by. It's the same reasoning that will put two quick meals into the microwave instead of one, give them the recommended time and wonder why they are still cold when they come out.
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mancan18 at 09:49 AM on 20 August 2014Global warming denial rears its ugly head around the world, in English
The problem with the media can also be put at the feet of the climate change proponents themselves. Rarely have I seen a breakup of the argument into the basic science, the evidence, the likely impacts and the political and economic solution. In the media, at one moment the media might be talking about the ice in Antarctica, then the next moment about why an ETS is needed, and then railing against some denier; rather than reminding the public of the basic science. There never seems to be a consistent argument from climate change advocates, and there never appears to be any challenge for the deniers to actually prove what they are saying. Now, in Australia, the Murdoch press and the major polluters have colluded to misinform the public and brow beat climate scientists. As a result, there is nowhere near the balanced reporting that the deniers demand. It is all in their favour. No wonder the Australian public is confused. But rather than stick to the basic science and assume that it is done deal, little effort is made by climate change advocates whenever they get the opportunity, to revert back to the basic science and challenge the deniers to actually prove their case. Deniers should be asked everytime they present an argument, to clearly explain exactly how can the planet cool, or how can the planet not warm up and remain the same if greenhouse gases have increased to the extent they have and continue to increase at the rate they are? Also, they should be asked to what level should we allow greenhouse gases to accumulate in the atmosphere before we do something about them? This is the basic science and very rarely does it rate a mention. Whenever a climate change advocate gets the rare chance nowadays to make an argument in the popular media, rather than bury the public in overwhelming evidence, it would be better to actually challenge climate change deniers everytime they make absurd statements. Ask them to prove that the basic consensus is wrong and ask them to prove that what they are saying is safe. Require them to prove that increasing greenhouse gases is safe and not change the climate rather than trying to use a shotgun of arguments to blast them out of the debate and in doing so confuse the public. Overall, in the popular media, there needs to be a more consistent approach based excusively on the basics clearly delineated between the science, the evidence, the impacts, and what we do.
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scaddenp at 09:10 AM on 20 August 20142014 SkS Weekly News Roundup #33B
I should say though that a long time scales, (100kya), thermogenic gas could be a significant feedback. This paper by two of my colleagues show what happens from a very cursory look and with just commercial modelling software. We havent been able to pursue the matter sadly. The paper also shows that on human time scales, thermogenic gas isnt much of an issue for climate.
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scaddenp at 07:50 AM on 20 August 20142014 SkS Weekly News Roundup #33B
1.6l/m2 for be a very respectable flow rate for a deep natural gas reservoir with its enormous pressure. That kind of permeability in tundra? with almost no pressure?
Your crater photo is methane coming up from a deep thermogenic gas reservoir under enormous pressure. Gas seeps are common (I have a database of around 600 of them from around NZ) and their flow rates have little influence on atmosphere. Its revelance to methane from tundra/hydrates would be nil. Now it is possible the methane in the Yamal crater is from deep thermogenic gas field but then it would have no relevance to climate change at all.
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ubrew12 at 07:12 AM on 20 August 2014Global warming denial rears its ugly head around the world, in English
Phill Marston@2. One analogy I like to put out to people is to think of the ocean as a trillion ton iron ball. We've been pushing on that ball for 150 years and it has begun to roll. Our scientists have recently noticed that it may roll over our children. If we stop pushing on the ball will it stop rolling? No. It'll keep rolling for some time before friction finally stops it, because its so huge. In fact, we have to stop pushing some 40 years before, to make it stop in time. So, yes, the lack of immediacy works in Murdoch's favor, but by this analogy it's possible to make people understand that the same mechanism that allows that lack of immediacy also arrests the immediacy of any response once we do finally take this issue seriously. I think its also helpful to remind people that one doesn't put on a seat belt in a car because one expects to get in a car accident. We do it because its just the prudent thing to do. So is action on Climate Change. Hopefully the scientists are wrong, but if they are not, we need to put some distance between our children and that trillion ton rolling ball.
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Ashton at 07:11 AM on 20 August 2014Global warming denial rears its ugly head around the world, in English
Phil Marston@2 Who warned the BBC and why? Surely presenting both sides of the argument is in the best interests of all. Isn't it? Obviously if the denier is unable to logically discuss the issue at hand this will be to the benefit of the believers (not sure if that is the correct term but it seems suitably opposite to denier).
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MA Rodger at 06:46 AM on 20 August 20142nd law of thermodynamics contradicts greenhouse theory
Dikran Marsupial @1477.
The passage you found in the Tyndall translation (actually @1446 although the link does the job) certainly makes the two-way flow explicit. It is perhaps still a bit obscure being within a footnote but I think if you also point out that the statements of the law nowhere say they aren't talking about net heat flow, then the footnote would be difficult to refute.
Also I wonder if describing the changing size of the vibrations of atoms in a solid that result in transmited heat by conduction may also be useful to show up how brainless the 'no heat shall pass from cold to hot' interpretation really is. Just as the nutters are arguing that by magic photons don't get fired at warmer objects, they also have to be arguing that vibrations only excite adjacent atoms in the direction of net heat flow. How can a vibration only act in one single direction? A mind-boggling requirement.
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scaddenp at 06:30 AM on 20 August 20142014 SkS Weekly News Roundup #33B
Michael, I dont follow. I cant see how methane can diffuse out of the hole faster than the mixing rate on the interface. Yes, CH4 will be faster than CO2 because diffusion rate is dependent on inverse square of molecular mass, but surely Graham's law more or less applies. I dont see the setup being any different to high school diffusion rate experiments really.
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rocketeer at 05:08 AM on 20 August 20142014 Arctic Sea Ice Extent Prediction
Seeing as how JAXA is reporting extent less than 5.7 X 106km2 two weeks before the start of September. the WattsWrongWithThat estimate of 6.1 is already out of the race.
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shoyemore at 02:17 AM on 20 August 20142014 Arctic Sea Ice Extent Prediction
I can't read Figure 4 (it is blank) and a popup keeps asking me for a server username and password to view it.
Monthly average sea ice extent seems to have regressed to the figure given by a linear fit to the historic points, so that is my crude guess, just about 5m km^2 or slightly less.
Any opinion on the "count the early melt pools" method we heard a lot about earlier in the year?
Moderator Response:[Dikran Marsupial] Sorry, problem with images should now be fixed, thank you for bringing it to our attention.
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franklefkin at 02:12 AM on 20 August 20142014 Arctic Sea Ice Extent Prediction
5.35 million square kilometers +/- 1 million
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Leland Palmer at 00:27 AM on 20 August 20142014 SkS Weekly News Roundup #33B
Hi chriskoz-
Well, the total area of the walls of the crater is about 71,000 square meters, assuming a 15 meter radius and a depth of 100 meters. So, that's about 1.6 liters of methane per second per square meter of crater wall.
Is that excessive?
I wonder how much methane is coming out of this crater in Turkey? It's been burning for 40 years, I guess.
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Phill Marston at 22:42 PM on 19 August 2014Global warming denial rears its ugly head around the world, in English
We know there is a scientific consensus about anthropogenic climate change and the problem is one for social science, not the physical sciences. As this (free) article from Nature Climate Change back in 2009 shows, people's attitude to the problem is determined by the likely immediacy of its effects on them and the prevailing political and media environment they occupy. Deniers know that they don't have to prove an opposing case; they only have to sow sufficient doubt in order to continue with a Business As Usual programme. The biggest obstacle to the public understanding of climate science in the modern English-speaking world is the media, with Murdoch's empire leading the debacle but with even organisations like the BBC trying to hard to present a 'balanced' view by reaching for a denier for every article (although they've been warned about this recently).
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chriskoz at 21:20 PM on 19 August 20142014 SkS Weekly News Roundup #33B
Leland@23-24,
While your idea of calculating the hole's emission rate from the measured equilibrium concentration at the bottom is interesting, your results are simply laughably exaggerated, even after the correction by a factor of E3 @24.
82kg/s, that's about 120m3 of pure methane per second! Do you see sizeable vents in the walls of the crater that would possibly provide such big flow? No way. Therefore your methane delivery would have to happen from the water at the bottom. Do you imagine the size of bubbles? This water would not look like a quiet puddle on the movie they've shown but rather like a boiling cauldron from hell. No one would be able to even approach the crater and abseiling along the wall as they've done to film the puddle would endup in suffocation.
I don't bother following your calculatrion/verifying your numbers. But I feel like your statement:
[my rate is] a factor of 1000 greater than Archer's calculation
actually favours Archer, because your rate seems like 1000times greater than the reality (which is a quiet puddle, not a roaring cauldron). I would not be surprised if the expert's calculation estimated hole's emission at ~80g/s exactly 1000times less than yours, in par with Archer's calculation. Said emission, coming from cracks in the bottom and tiny bubbles in water mixes with the air volume at the bottom 1m of the crater and results in 9% concentrate as measured by some hand-held spectrometer. The spectrometer gives the highest readings of 9% in the pockets close to the vents at the bottom. By the time that methane reaches the lip, it's already dilluted close to the background levels. Proof: the abseiler who filmed it did not hesitate to go and apparently survived.
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michael sweet at 19:53 PM on 19 August 20142014 SkS Weekly News Roundup #33B
Scaddenp,
I think in this case it is possible for the methane to rise because it is not well mixed. If the gas in the hole has a higher concentration of methane than the surrounding air it will be less dense and move as a bulk. Once out of the hole, wind will mix the bulk around and distribute the methane. Once it is well mixed it no longer rises. I do not know how to do the calculations, but it has to be considered.
Carbon dioxide can be held in a covered container because it is heavier than air. If the cover is removed the CO2 will stay in the container for a long time until air currents slowly mix it with the surrounding air. Hydrogen can be contained in a container with an open botton.
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scaddenp at 19:18 PM on 19 August 20142014 SkS Weekly News Roundup #33B
Um, are you not implying because methane is lighter than air, it must all go up? In what way is that different from the idiots that claim that CO2 must stay close to ground because it is heavier than air? The change in gas concentration in the crater must be governed instead by gas diffusion laws.
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Leland Palmer at 16:02 PM on 19 August 20142014 SkS Weekly News Roundup #33B
Woops, that's in billions of kilograms, not in billions of metric tons. So, make that 0.0003 gtons- still a factor of 1000 greater than Archer's calculation.
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Leland Palmer at 15:53 PM on 19 August 20142014 SkS Weekly News Roundup #33B
Hi scaddenp-
OK, one more (new - Moderator please note) point and then I'll shut up, at least for a while.
I think Archer may have missed the point, by considering only the initial release of methane. The crucial question might be - how much methane (which is lighter than air and so is bouyant) would have to be released at a constant rate to maintain an equilibrium concentration of 9% in the bottom of such a crater for a long period of time? The measured concentration at the bottom of the crater a couple of weeks ago was 9%.
From Wikipedia:
"Dry air has a density of about 1.29 g/L at standard conditions for temperature and pressure (STP). Methane (density 0.716 g/L at STP, average molecular mass 16.04 g/mol) is the chief component of natural gas and is sometimes used as a lift gas when hydrogen and helium are not available."
To maintain a constant concentration of a bouyant gas must require a constant flow of methane into the crater.
My spreadsheet calculation says that about 82 kg per second of methane would be released to maintain that 9% concentration, as a very rough approximation using Newton's laws of motion and making conservative assumptions. That's assuming a 25 meter square column of gas that is 9% methane and 100 meters high is providing the bouyant force. I get an acceleration of about 0.04 meters per second squared, and a final velocity of about 2 meters per second for the entire column of 9% methane.
So, over 100 years, that's about 0.3 gigatons of methane - roughly 100,000 times Archer's number.
That seems high, no doubt that flow would decline over time. At least, I hope it would. As the flow declines, the bouyant force would also decline. Still, it looks like Archer was asking the wrong question, by limiting himself to a calculation of the initial methane release, and was likely low by a factor of at least 1000.
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scaddenp at 07:17 AM on 19 August 20142014 SkS Weekly News Roundup #33B
The mechanism proposed so far by Phekhanov and others is for pressure release of hydrates as the tundra has warmed. This is plausible. I dont see a plausible mechanism for the crater from release of deep thermogenic gas, and if one was shown to exist, it certainly wouldnt be related to global warming. The other events you mention are still associated with a continental configuration including large shallow seas and thus potentially lots of hydrate. Got a paper that claims the excursions are from a spontaneous release of hydrates? I am familiar with PT and PETM literature but I admit to know little about a Triassic event.
What Archer and others are pointing out, is that is very difficult to find a credible mechanism for producing dangerous amounts of CH4 in the modern world, which makes such claims unduly alarmist. Far from being out by 10 or 100, I think you should note that Archer used an impossible upper end for methane content. We have quite enough problems with CO2 emissions. Truly alarmist claims simply result in lost crediability and distract from the real problems.
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Ashton at 02:22 AM on 19 August 2014Global warming denial rears its ugly head around the world, in English
Unfortunately I think you'll find that almost always reports in the MSM (yes even the reviled MUrdoch papers) reach many, many more readers than does SkS, Real Climate. Open Mind etc. Given that, it is unlikely this analysis will have much effect on the average citizen. Getting a piece into a newspaper, other than The Guardian which is not a high circulation paper as it is regarded by many as a subversive, left wing publication (despite the brilliant Feicity Loake), will achieve much more than 10 pieces here. And yes. I am aware of John Cook's 97% paper and the subsequent comments both for and against that paper. Why not see if Fairfax or indeed News Ltd will publish this piece?
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Dikran Marsupial at 00:28 AM on 19 August 20142nd law of thermodynamics contradicts greenhouse theory
MA Roger, while the translation doesn't explicitly use the phrase "net flow of heat", I think it is implicitly clear in the translation of the first edition of Clausius' textbook in the footnote mentioned in my post at 1146:
"In the first place this implies that in the immediate interchange of heat between two bodies by conduction and radiation, the warmer body never receives more heat from the colder one that it imparts to it."
The only way for this to be satisfied (in the absence of "some other change") is for the net flow of heat to be from the warmer to the cooler body.
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Leland Palmer at 00:22 AM on 19 August 20142014 SkS Weekly News Roundup #33B
Hi chriskoz-
Archer thinks he can predict what will happen.
I don't think so.
We've now seen three cold gas eruption events. Does anyone doubt that there will be more?
This new explosive release plus slow subsidence mechanism needs to be factored into all future scenarios. We need to find out- urgently- how much methane this mechanism will release, and how much it has released in the past.
Beyond that, we need to just stop experimenting on our planet, and introducing factors that no one is competent to predict. Isaksen wrote his paper before he knew about this new explosive release mechanism. I wonder what he would say, now.
The laws of physics will not be denied. Permafrost melts and gas expands when heated. Heat millions of square kilometers of permafrost, and we run the risk of setting off side effects that no one is competent to predict.
Moderator Response:[JH] You are now skating on the thin ice of excessive repetition which is prohibited by the SkS Comments Policy.
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One Planet Only Forever at 00:12 AM on 19 August 2014Climate scientists dub this year’s El Niño “a real enigma”
It is clear that the intricacy of the global system related to the ENSO is worthy of the pursuit of better understanding. Being able to better predict its formation will benefit the many actvities, including plans for potential emergency response, affected by the global influence of this condition.
However, it is possible to clearly show that the expected warming of our planet by the increased CO2 has been occurring and is evident in not only the deep ocean temperatures, but in the global average surface temperature data. Though this El Nino has not yet fully developed the way some models predicted, the 12 month global average surface temperature is currently warmer that the highest 12 month value during the very strong 1997/98 El Nino.
In the NASA GISTemp data set, and probably in the other data sets, the recent averages of 12 months have been warmer than the warmest 12 month average during the 1997/98 event. The maximum 12 month averages during that event were 0.61 C for periods ending in August and September of 1998, after the tropical Pacific had cooled - as measured by NOAA as the ONI. The 12 month averages ending in May, June and July of this year are 0.65 C, and the tropical Pacific has not yet warmed to El Nino levels.
This is another clear indication that the warming so many want to believe has not been continuing has actually continued. And there is no need to wait for the 'full formation of an El Nino' or for the end of the year global surface 12 month average to point out the clear facts of the matter.
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chriskoz at 23:30 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Leland@15,
The study you cite explicitly says:
Although the high‐CH4 scenarios applied in this study are unlikely, they demonstrate the strong CH4 feedbacks in the climate system, with large amplification of atmospheric composition changes and RF compared to the direct RF of CH4 emissions.
I would use even strongeer language: "very unlikely". 2.5 times the rate of current CH4 emissions is where they start their experiments. Note, the current emissions (500Mt/y of which about third can be antropo emissions from FF leakage) already have been shown to be the central estimate of PETM rates (if sustained over several ky). This is the real problem. And the CO2 rate is much larger: 10GtC/y and growing. The potential addition to that rate from thawing permafrost has been shown to be miniscule by comparison.
Expert like David Archer repeat that permafrost feedback is very slow. When talking about deep geological past in search for examples that unleashed said feedback, we need to be aware of the necessarily very long timescale of such events. I speculate (i'm not expert not even familiar with the processes triggering them) they can be even slower than for example orbital forcings. If it wasn't so, then we would have observed such feedback more frequently in the past (say every few orbital cycles of 100ky, rather than only couple in the entire 65My history of Cenozoic).
So, it is unlikely that 2.5 the rate of CH4 feedback will kick in next couple hundred y. The problem of FF emissions is occuring at least 100times faster, therefore its effects may come and go (assuming people grow up to the task of successful mitigation and end up with zero emissions soon), before permafrosts starts thawing. That's IMO the most likely scenario, based on our best knowledge, without scaremongering.
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MA Rodger at 22:45 PM on 18 August 20142nd law of thermodynamics contradicts greenhouse theory
MattJ @1451 & @1455.
@1451 you use words of mine @1436 to exemplify "many people here get on their high horses in defense of science — yet show they cannot even read well enough to do it."
@1455 you complain of "three simple questions" that have failed to be answered here.
It is worth considering the reasons for both these complaints as they have a common source. My input @1436 pointed to potential confusion created @1435 which is also where we find your "three simple questions."
Perhaps I should give three simple answers - (1) What is the "it" you are asking about? (2) Who do you think we are, Sky Dragon Slayers? (3) See (2).
And be mindful, MattJ, that @1435 there had already been a prior trail of alleged missed points and disputes over what you had actually written.Seeking some semblence of sound thinking, we can look back to MattJ@1429 - "It does no good to quote the Second Law incorrectly, and then say, "it does not contravene the second law of thermodynamics" ... since you are still requiring radiating CO2 molecules in a -20C stratosphere to heat up an ocean layer that is on average above +20C ... it is still a violation of the "imaginary second law", but not of the law as Clausius really stated it." (Note my editing here makes things a whole lot clearer.)
Simply MattJ argues that the statement of the Second Law as presented in the SKS post is inadequate. He suggests using the WIkipedia version (from Clausius (1854) - an 1856 translation here) to overcome the inadequacies of the version used by the SKS post. Meeting a rebuff on this MattJ, you compound the confusion with comments that are pretty dire at describing your position and in detail packed with trollish statements.Now, if your "it" in your first question @1435 encompassed the whole of that '@1429 statement' presented above, then there is sensible discussion to be had. For myself, I see a lot of scope for improving the post but I am not convinced that some pre-photon eighteenth century quote will expose the nonsensical cherry-picking of Sky Dragon Slayers and their ilk, however authoritative the quote. Do note in the quote from Wikipedia and its source, Clausius still talks throughout in terms of "the interchange of heat between two bodies of different temperatures" and, beyond the implications of the word 'interchange', never makes clear that he talks of 'net heat flow.'
However to argue the "it" actually is the whole statement @1429 would be rather difficult as it requires some strange interpretation of the words used.
So my response to MattJ @1451 is this - It is not my reading of the words that is at fault but instead the fault lies with the writing of the words I am being expected to read. -
MA Rodger at 22:13 PM on 18 August 2014Error identified in satellite record may have overestimated Antarctic sea ice expansion
BojanD @22.
The transition from V1 and V2 (or V2 to V1) does indeed constitute the error in question. When you say there may be "a minor mistake lurking," do you really mean to suggest there is still something 'lurking' beyond the chosen method being properly applied, another abet minor V1toV2/V2toV1 mistake? I mention this as I can but assume such a harsh meaning is not intended. Yet it is still made.
Regarding your "enigma," it is your creation but its definition as you have described it down this thread has now become itself 'enigmatic'. (And I would add that the Nature article linked @15 had effectively made the "much more closely" comment which was also illustrated in the Supplimentary Discussion & Figures of Eisenman et at (2014) data for SIE (although not the SIA data), so the NSIDC post should not come as some recent revelation.) -
newairly at 19:55 PM on 18 August 20142014 SkS Weekly News Roundup #33C
"Why We're Definitely Not Headed for Another Ice Age"
is behind a paywall
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Dikran Marsupial at 18:21 PM on 18 August 20142nd law of thermodynamics contradicts greenhouse theory
MattJ wrote "For he does say it expresses the same idea as "by itself", and we all agree that the heat transfer from colder CO2 to warmer ocean thin surface layer is ultimately driven by the energy input from the sun, it is not "taking place 'by itself'".
I think you still have not quite understood. While the original source of the heat is the sun, the upper atmosphere is warmed by outboud IR radiation emitted by the surface. Thus the interchange of heat between the surface and the upper atmosphere (no need to mention the sun at all) involves a greater transfer of heat from the surface to the atmosphere than vice versa.
It would be more accurate to say that the backradiation is not compensated by energy from the sun, but that it is directly compensated by outbound IR from the surface.
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Dikran Marsupial at 18:17 PM on 18 August 20142nd law of thermodynamics contradicts greenhouse theory
MattJ wrote "I am genuinely surpised at your interpretation of the word 'generally'. I would have thought English is nor your native language. Either that, or you are the one who is 'digging' and engaging in pedantry."
As it happens, English is my first language (my second being MATLAB). In the context of the quote the word "generally" indicates that there are exceptions to the rule as stated, see e.g. the third definition given here):
3. without reference to or disregarding particular persons, things, situations, etc., that may be an exception:
What could those exceptions be? Rather obviously the exceptions are the cases where there are "some other changes...".
This doesn't weaken the second law at all, it is just a statement of only the general case of the second law, where the exception is not relevant (such as the case for the greenhouse effect, where no "some other change" need be introduced to explain what we observe).
The problem appears to be that you are unaware of a (perhaps idomatic English) usage of "generally", not that there is something badly wrong with the quote. As it happens, I am working on rewriting the article, and I shall use quotations from the translations of Clausius' book.
Now I asked: "MattJ@1460 does that mean you now agree with me on my interpretation of the second law of thermodynamics only applying to the net transfer of heat, and hence there is no need to introduce the "other changes" clause?"but you appear to have ignored yet another of my questions.
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Leland Palmer at 16:05 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Hi scaddenp-
"The natural gas fields that you are associating with the methane hydrate are deep thermogenic gas."
I don't recall saying that these gas eruptions are associated with methane hyrates -just that they could be. I don't know that there are hydrates in the eruption craters, I just said that assuming only gaseous methane under pressure makes the calculated release smaller, I think. Maybe there are hydrates associated with these eruption events, maybe not. Maybe the methane is biogenic, maybe it's thermogenic. Permafrost can contain hydrates, but we don't know yet that these eruption events are associated with hydrate.
About the PT extinction, if I don't get carried away about that one, there are a series of carbon isotope excursions associated with extinction events that I can get carried away about instead. The largest calculated methane release I am aware of in a peer reviewed paper is one that claims a total release of about 12 trillion tons of carbon (16 trillion tons of methane) during the End Triassic.
There are hundreds of peer reviewed scientific papers that agree with the methane release explanation for the carbon isotope ratio excursions associated with a variety of mass extinction events. So, what would you be willing to bet that they are wrong? Would you bet the planet on it, for example?
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scaddenp at 15:23 PM on 18 August 20142014 SkS Weekly News Roundup #33B
I wouldn't get too carried away with PT extinction. Hydate release is but one hypothesis and like the others has it's strengths and weaknesses. Hydrate release could have been a contributing side-effect with others being the cause. The globe was a very different place in PT, including have much larger areas of shallower seas (and thus hydrates). It is an interesting problem but not one that you can use to draw too many conclusions about what might happen in the modern world.
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scaddenp at 15:17 PM on 18 August 20142014 SkS Weekly News Roundup #33B
The natural gas fields that you are associating with the methane hydrate are deep thermogenic gas.
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Leland Palmer at 15:14 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Hi scaddenp-
"But I would also note you have such lakes and landscapes without any gas fields." Maybe. Some areas could be depleted enough by the eruption scenario of 8000 years ago that they fall below the threshold for commercial desirability. Or maybe there are such lakes and landscapes, currently free of methane. Or, maybe nobody has happened to drill in those areas. It's too soon to know, the hypothesis is still too new.
"Leakage of methane from thermogenic reservoirs can definitely create methane hydrates but they have a different chemical and isotopic signature to biogenic hydrates that are normal for permafrost. "
Huh? Who said anything about thermogenic methane? Most of it is of bacterial origin, and certainly isotope ratios can be used to investigate the origin of the methane, but so far as I know, we are talking about normal C13 depleted C12 enriched bacterially generated methane in the eruption scenario, with a bit of random thermogenic thrown in.
Having said that, it looks like an interesting link, and I'll read it. I'm not sure that how that applies to this eruption scenario, though.
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Leland Palmer at 14:57 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Hi chriskoz-
To make it short and sweet, methane is scarier than CO2 because of the carbon isotope excursions associated with past mass extinction events like the End Permian, plausibly due to the release of trillions of tons of methane from the oceanic methane hydrates. The End Permian killed upwards of 90 percent of all species- surely more than 99% of all individual organisms. And the sun is hotter now than it was then, by a couple of percent- an effect Hansen says is equivalent by itself to 1000 ppm of CO2.
Two major greenhouse gases is much scarier than one, mainly because infrared absorption bands get saturated, and because of the ability of methane extend to extend its own lifetime through degradation of the hydroxyl radical degradation mechanism. And three major greenhouse gases is worse than two, if you figure that water vapor will increase about 7% per degree of warming, whether that warming is due to CO2 or methane.
Then there are the atmospheric chemistry effects of methane, and the oceanic chemistry effects of methane.
Strong atmospheric chemistry feedback to climate warming from Arctic methane emissions
"The indirect contribution to RF of additional methane emission is particularly important. It is shown that if global methane emissions
were to increase by factors of 2.5 and 5.2 above current emissions, the indirect contributions to RF would be about 250% and 400%, respectively, of the RF that can be attributed to directly emitted methane alone. " (RF is an abbreviation for Radiative Forcing)For the oceanic chemistry effects of methane, read Peter Ward's book "Under a Green Sky".
No, methane is definitely scarier than CO2. The runaway feedback effects of methane are far, far scarier.
Methane is why we need to ban fossil fuels, not just decrease their use.
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scaddenp at 14:37 PM on 18 August 20142014 SkS Weekly News Roundup #33B
But I would also note you have such lakes and landscapes without any gas fields. Leakage of methane from thermogenic reservoirs can definitely create methane hydrates but they have a different chemical and isotopic signature to biogenic hydrates that are normal for permafrost. I didnt find data for Yamal though in a quick look. Do you know of any? Examples of analyses from elsewhere in Siberian permafrost can be found here. Occam's razor only applies when you have hypotheses that can equally explain the data. I am not sure the data shows that.
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chriskoz at 14:25 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Leland Palmer,
You seem to be missing the final point of David Archer's RC article:
In conclusion, despite recent explosions suggesting the contrary, I still feel that the future of Earth’s climate in this century and beyond will be determined mostly by the fossil fuel industry, and not by Arctic methane. We should keep our eyes on the ball.
Maybe because David did not clearly compare his GHG numbers coming from this "hole from the end of the world" with the FF emission numbers.
So let's try to hypothesize and assume the worst, that this hole is heralding a new PETM-like event. What type of CH4 emissions and what magnitude of GHG forcings can we expect as the result of such bold assumption? There is extensive literature on that subject. Let's take for example Schmidt & Shindell 2003, their Table 2 on p4 lists the possible PETM scenarios. The scenario David is talking about is the release of couple Gt/y on a short timescale. That corresponds roughly to this row in said table:
Experiment: 0.3 Gt/yr (5 kyr)
Atmospheric Concentration Increase (ppmv)
CO2 : 100
CH4 : 1.8
H2Ostr: 0.6
Forcing (W/m2)
CO2: 1.9
CO2+CH4: 2.6
Note the CO2 increase of just 100 (compared to antropo 120 already and rising). Also note the forcing in bold: it is about the same level of forcing antropo emissions have already achieved and rising. That should be really scary to you, not your tale from "the end of the world".
So, according to your own ockham's razor principle, you should be looking at the hints of what's already happening, rather than at the unsubstantiated speculations. To give you the examples of latest developments that should look "scary" to you, read those economic/political events/comments that incidentally could have been the topics of this Roundup. The news are from my part of the world. I don't know what part you live in, perhaps closeby as you're posting at the same time herein.
Claims of Australia's biggest oil discovery in 30 years
The dicovery is not that surprising to me. But the fact that:
Shares in Australian company Carnarvon Petroleum, a junior partner in the venture, instantly more than doubled on the news
look scary to me. Another scary news is the comment by this guy (the current OZ PM business advisor):
which means the politicians are complete nutters and ignorants when it comes to the AWG problems.
That's the ball David warns that you should keep your eye on. The methane tale should not obstruct that view.
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Leland Palmer at 14:11 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Hi Tom Curtis-
"The current crater is of the same size as the "thousands" of little lakes on the Yamal peninsular, as can be seen by the video on the article to which you link, and which speckle the photo you showed."
Oh, I wasn't just talking about that one area of the Yamal Peninsula, Tom.
I was talking about the probably hundreds of thousands of generally circular lakes, of all sizes, that cover maybe 5 percent or so of the 13 million square kilometers of Siberia, and even a couple of small areas of the Canadian Archipelago. I urge you to fly around a little using Google Earth, and tell me what you see.
I really, really hope that they are due to thermokarst processes. I hope that there is another explanation for the apparent association of these lakes with the huge methane gas fields in the area. Occam's Razor works better with simpler systems than the whole planet, and two processes producing similar looking holes operating in the same area is not impossible - it just seems unlikely to me.
I really hope we will not see an accelerating series of methane eruption events- of all sizes- as the permafrost thaws, and subsequent slow releases of methane from enlarging craters. So far, we've apparently seen 3 such events - and it only takes two events to make a pattern.
But, thawed permafrost is weaker than frozen, and heated gas expands, and we are heating millions of square kilometers of permafrost with our human caused global warming.
And, the laws of physics and chemistry will not change just because we want them to. Ice still melts and gas still expands, and we really should not be surprised if the unexpected happens when we experiment on an entire planet.
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Leland Palmer at 13:15 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Hi scaddenp-
I hope you are right, about the thermokarst. Phekhanov and his collaborators seem to take the eruption hypothesis seriously, though, and surely if anyone would know about thermokarst, these Russian scientists would.
Our modern rate of waming is much faster than past events, and is certainly much more systematic. Past events have not had the terrible consistency of human fossil fuel based climate forcing. So, things that took a couple of thousand years in the early Holocene could easily take only a hundred years now.
I'd like to see a serious calculation done, one that looks seriously at how much methane could be released by a realistic distribution and number of eruption events and a realistic duration of subsequent slow subsidence events. Nobody has done that, yet, that I know of, and I look forward to seeing the results.
I'm not convinced by Archer's calculation - it could easily be off by a factor of 10 or even 100, if methane continues to flow into the crater over decades or centuries.
And this first eruption event could be a tiny one, compared to the ones that may come.
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Leland Palmer at 12:50 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Hi Tom Curtis-
Yes, we can argue the math. But we do have a process going on - abrupt global warming in the Arctic - which could produce very large numbers of simultaneous eruptions- and we don't know that they come in only one size. This mecanism could produce enough eruptions, of various sizes, perhaps, to fit Archer's reqirements for concern.
Global warming can also simultaneously produce other, perhaps larger, emissions of methane.
Or, this new explosive release plus slow subsidence mechanism could be the answer to the riddle of past methane catastrophes. This mechanism could form a bridge from a triggering mechanism like orbital forcing or a flood basalt eruption to a general release of methane from the oceanic methane hydrates.
Why draw a distinction between the large Yamal lakes and the smaller ones? Looking at the topography, which I urge you to do, these circular lakes come in all sizes. Perhaps the large ones are the result of the fusion of multiple eruption craters, but what we are concerned about the most is the total amount of methane released.
Do you believe that there is a bimodal size distribution? If so, that's interesting, and could be a clue to the nature of the process.
We're concerned about the total amount of methane released, not the amount released from any single event- or even the amout release by any single mechanism.
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scaddenp at 12:24 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Even if all the "lakes" are methane craters, it is still not an issue if they formed over the whole of the holocene. Archer is asking how many craters do you need a relatively short period before there is problem. The methane in atmosphere from past outgassing of hydrates is clearly not an issue so you can only have a problem if there is a huge increase in rate. Without some detail on geology and detailed morphology of lakes, it's a bit premature to conclude that they are methane eruptions. Simple thermokarst lakes seems at least as likely.
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Leland Palmer at 12:22 PM on 18 August 20142014 SkS Weekly News Roundup #33B
I don't think that Plekhanov and his collaborators are proposing that the large circular lakes on the Yamal Peninsula were formed exclusively by an explosive process.
What he is saying, I think, is that an explosive eruption creates the first deep crater. That crater has a lake in the bottom of it. The lake undercuts or weakens the edges of the crater, and the edges keep falling into the deep crater. So, the craters enlarge in diameter but get much shallower as this process continues for decades or centuries.
But, during the enlargement process, I'm afraid that much more methane will likely be released than was released during the initial gas eruption.
Without the evidence of the crater itself, this whole process seems unlikely, which may be why the original hypothesis died in the 1980's- for lack of evidence.
Suddenly, though, with the generation of these 3 craters, the logic changes. Project the processes we see at work on this crater into the future, and what we get is a circular lake, just like the tens or hundreds of thousands of other circular lakes in this area of Siberia.
Saying that there is another explanation for these circular lakes suddenly seems to violate Occam's Razor. We would be postulating an unknown process to explain them, when we already know one process that could produce them - the eruption plus progressive enlargement process.
Except, the other lakes in the area are much, much bigger. One of the lakes near the Yamal crater is about 10 miles in diameter - at least 100,000 times the area of the current Yamal crater. So the inital eruption that may have produced this lake would have had to be much, much larger than the current Yamal eruption.
Can we safely ignore this chain of logic, and hope that there really are two unusual processes producing circular holes in these same geological areas, which just happen to sit above giant natural gas fields?
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Tom Curtis at 12:18 PM on 18 August 20142014 SkS Weekly News Roundup #33B
Leland Palmer @6:
1) The current crater is of the same size as the "thousands" of little lakes on the Yamal peninsular, as can be seen by the video on the article to which you link, and which speckle the photo you showed. This is particularly the case as erosion will fill the great depth of the creater by broadening the surface diameter. It is not the same diameter as the large lakes that dominate that picture, but there are not thousands of such lakes. Rather, there are about 34 of them, with the cluster of lakes in the picture being both the largest such cluster, and containing the three largest lakes on the peninsular. You can do your maths on the thousands, or on the thirty four. What you cannot legitimately do is do the maths on the three largest out of the 34 lakes, and multiply that out by the "tens of thousands".
2) The lake with the largest diameter, and the most circular of the three large lakes in the cluster has a diameter (generously) of 16 km, giving it at most an area 40,000 times that of the crater analysed by Real Climate. Based on that, the formation of the entire lake cluster would have released approximately 3 x 40,000 x 0.000003 (= 0.36 Gtonnes of methane) or 0.72 ppmv of methane. That is a 40% increase on the current concentration, but only 0.7% of a Sarkhova event.
You can argue details of that calculation. I would argue it is a probable overestimate in that the lakes were likely formed by the formation of a number of smaller crates which were then joined by erosion. To that point I note that they are not circular, and most of the large lakes are not even close to circular. Against that you might argue that a crater formed with a larger diameter would also have a greater depth of the methane chamber exposed, and hence more methane overall. While possible (indeed, probable for the intermediate and actually circular lakes of which there are many), it is invokeing a greater complexity in the phenomenon, and hence runs up against ockham's razor itself.
3) Regardless of how we do the maths on the lake complexes, for them to even contribute a 10% Sarkhova event, all the lakes and small craters must have formed more or less simultaneously. Even spaced out over a few centuries the rapid conversion of methane to CO2 in the atmosphere would mean the forcing would be best modified by a 1 or 2 ppmv increase in atmospheric CO2, which is inconsequential.
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Leland Palmer at 10:56 AM on 18 August 20142014 SkS Weekly News Roundup #33B
Hi Tom Curtis-
David Archer of Real Climate essentially calculated how much methane it would take to fill a hole the size of the current crater in Yamal, under a certain amount of pressure. It's not really a very big crater, and is less than 100,000 times the area of some of the large circular lakes on Yamal.
I would like to know how much methane would be released if Plekhanov's mechanism for forming the tens of thousands of circular lakes in the area is correct. It's not at all the same calculation, and the results could easily be different by millions of times.
It seems strange that there would be two geological processes for forming circular holes in the same area. This seems to violate Occam's Razor.
It seems strange that the circular lakes seem to concentrate in the same vicinity as current huge gas fields supplying a substantial portion of Europe's natural gas.
I don't want to borrow trouble, but I don't want to hide from it, either.
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Tom Curtis at 10:21 AM on 18 August 20142014 SkS Weekly News Roundup #33B
jenna, I'm not sure "breathing a sigh of releif" is the appropriate reaction in that we have got genuine problems enough from global warming. Perhaps, let's just not buy trouble when we are in over our ears already.
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jenna at 10:05 AM on 18 August 20142014 SkS Weekly News Roundup #33B
Thanks to Tom @3 for posting the link to the Real Climate article. I knew I had read that "sanity check" about methane releases somewhere but couldn't find it. Let's all breahte a sigh of release on that one!
Jen
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Tom Curtis at 09:40 AM on 18 August 20142014 SkS Weekly News Roundup #33B
Leland Palmer @1&2, Real Climate had a recent article on the release of methane by eruption craters:
"If the bubble was pure methane, it would have contained about … wait for it … 0.000003 Gtons of methane. In other words, building a Shakhova event from these explosions would take approximately 20,000,000 explosions, all within a few years, or else the climate impact of the methane would be muted by the lifetime effect."
As a further sanity check, those thousands of lakes probably formed during the transition from the last glacial to the current interglacial. That transition did not trigger a massive methane driven global warming event. Therefore they are not evidence that the current warming will do the what did not occur when they were formed.
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Leland Palmer at 09:05 AM on 18 August 20142014 SkS Weekly News Roundup #33B
Seriously, I invite other readers to look at the areas on this natural gas field map of Siberia in Google Earth, and see if they see the same correspondence between gas fields in the present and possible erruption craters in the past as I do:
The Yamal Peninsula is in the upper part of the image, in the left center. But most or all of the major gas fields marked on the map seem to be seriously pockmarked with thousands of possible methane eruption/subsidence craters, when you go to the corresponding areas in Google Earth and look for them.
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Leland Palmer at 08:36 AM on 18 August 20142014 SkS Weekly News Roundup #33B
Regarding the changes in the Arctic, those Siberian Yamal Peninsula craters and the other Arctic methane stories are seriously scaring me. Not only are the stories about large methane emissions from the ESAS recorded by the oceanic expeditions scary, but so are the news stories above and the implications of the new explosive mechanism for releasing methane by methane eruption events.
Looking at Siberia with Google Earth, large areas are covered with tens of thousands of circular lakes and circular landscape features, and some of them are ten miles or so across. It seems possible that those tens of thousands of circular depressions were generated by similar methane gas eruptions, followed by melting of ice and methane hydrate and subsidence to enlarge the initial gas eruption craters.
Andrey Plekhanov, Senior Researcher at the State Scientific Centre of Arctic Research, thinks this might be the case:
Quoting Plekanhov- “‘I also want to recall a theory that our scientists worked on in the 1980s – it has been left and then forgotten for a number of years.
‘The theory was that the number of Yamal lakes formed because of exactly such natural process happening in the permafrost.
‘Such kind of processes were taking place about 8,000 years ago. Perhaps they are repeating nowadays. If this theory is confirmed, we can say that we have witnessed a unique natural process that formed the unusual landscape of Yamal peninsula.”The Yamal area gas fields, by the way, have been supplying large quantities of natural gas to Russia and Europe for decades, so there is a lot of methane in the area. Looking on Google Earth at the areas of Siberia that contain those giant methane gas fields, they seem pockmarked by thousands of circular lakes and other landscape features. There seems to be a visual correspondence between gas fields and the thousands of possible past methane eruption/subsidence craters.
We need to do a realistic calculation to of the methane generated by the hundreds of thousands of square kilometers of circular Siberian landscape features which could plausibly have been generated by this process.
Since erosion might soon erase such landscape features, it seems possible that most of the circular features visible using Google Earth were generated in a burst of methane gas eruption activity a few thousand years ago, perhaps in the early Holocene, as Plekhanov suggests.
Perhaps, no realistic scenario exists that would release sufficient methane rapidly enough to make a big difference. But, our rate of change of temperatures in the Arctic is very, very rapid, and a similar burst of methane eruptions might occur more rapidly now than in the early Holocene.
And, of course, these possible widespread methane gas eruptions are not the only change occurring in the Arctic, as permafrost melts and decomposes.
What are the possibilities of similar eruptions occurring in the shallow waters of the the East Siberian Arctic Shelf, as the shallow underwater permafrost there melts and potentially uncaps more reservoirs of methane?
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Tom Curtis at 08:32 AM on 18 August 20142nd law of thermodynamics contradicts greenhouse theory
DSL, I don't know about burrying it, but a strong case for locking this thread can be made, and would be supported by every SkS commentator. Notifications of any errors in future edits could be made by email, and if somebody realy thinks they have a strong case for violation of the 2nd law, they can email a copy of a blog post as well, which can be published with or without reply should they be able to convince an "editor" and "two referrees" from the SkS team that that should be worthwhile.
Surely everything that is worth saying on this thread has already been said repeatedly.
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