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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 56151 to 56200:

  1. 2nd law of thermodynamics contradicts greenhouse theory
    Silas - I would suggest, as Composer99 recommended, to look at the Science of Doom site (search there for "Gerlich"), including such gems as On the Miseducation of the Uninformed by Gerlich and Tscheuschner (2009) and Radiation Basics and the Imaginary Second Law of Thermodynamics. Quite frankly, I cannot think of another paper in the field that has been so definitively and repeatedly shown to be dreck. G&T's work is absolutely horrible...
  2. 2nd law of thermodynamics contradicts greenhouse theory
    Not this again! Silas: There is an enormous body of theoretical, experimental, and most importantly empirical evidence showing that the atmospheric greenhouse effect, however misnamed, is fact. It does not violate any law of thermodynamics, it does not allow any sort of perpetual motion machine. Gerlich & Tscheuschner are, simply put, wrong, wrong, wrong. For more in-depth information you can check out the blog Science of Doom which has some reviews of the G&T paper here. You can also check out some other important Science of Doom posts regarding the relevant physics here and here. Science of Doom relies heavily on the actual maths of the situation and basic radiative physics known for decades.
    Moderator Response: [DB] In addition to the valuable links provided by Composer99 above, please see this SkS post, Has the greenhouse effect been falsified?.
  3. 2nd law of thermodynamics contradicts greenhouse theory
    @ RW1 at 11:08 AM on 16 December, 2011 "There is no violation of the second law with the Greenhouse Effect, because it's not about energy going from cold to warm through a conduction process." You are confusing radiation (electromagnetic waves) with creation of thermal energy (heat). Heat is a process involving transfer of energy based on temperature - as opposed to generic radiation of photons. It follows that thermal radiation (a process creating heat) from a cold to a hot body (i.e. from the atmosphere to the Earth) is a physical impossibility. The Second Law prevents this because otherwise it would be possible to obtain work from transfer of heat into the atmosphere; i.e power station cooling towers. Essentially, we could then reuse the energy and build a perpetual motion machine. AGW is predicated on a misunderstanding of the Second Law which is thoroughly debunked by eminent German physicists (as opposed to climate scientists who are generally not professional physicists) Gerlich and Tscheuschner.
    Moderator Response: TC: Link to RW1's post added.
  4. Hurricanes aren't linked to global warming
    David: In addition to the comments by Dikran and DSL, I should like to note that the additional energy in the system resulting from greenhouse warming is not evenly distributed, temporally or spatially. As such the potential exists for larger gradients leading to more intense storm activity, as suggested by the Intermediate version of this article and comment #47 (although as per that comment and the IPCC SREX more research is needed to confirm whether this is occuring).
  5. New research special - satellite measurement papers 2010-2011
    ModResponse@5: Sorry, I was just showing off my *mad skills* by hot linking the already-extant unhot link in Comment 2...that's what I get for being helpful...;)
  6. New research special - satellite measurement papers 2010-2011
    Re: Record Greenland Ice Melt To be fair, it should be highlighted that this seems to be a cyclical thing (why?) which they also mention in the article itself, so the event as such is not that interesting. What is interesting is, what has caused it, and will the trend change. Maybe this is linked to what the Mernild et al. (2011)-paper describes?
  7. Earth hasn't warmed as much as expected
    Maybe they're making an example of Lindzen. I'd hate to think they're being "fair and balanced" in representing the science. The climate security material on the Sandia website seems like they get it.
  8. Hurricanes aren't linked to global warming
    So, David, if a difference exists "normally," then adding more to one side of the equation wouldn't produce a greater difference? The vertical profile of GHE warming is not uniform. The lower troposphere is warming at a greater rate than the upper troposphere. According to your understanding, would that not create a greater temp difference? lower trop = 0.134 K/decade mid-trop = 0.079 K/decade tropopause = -0.011 K/decade lower strat = -0.302 K/decade That's a simplistic answer, but your response was simplistic. This is not a simple box model we're dealing with. Tropical convection doesn't occur absent of other large-scale forces (increased available water vapor, for example). I'm also thinking you didn't click on the "intermediate" tab above.
  9. Dikran Marsupial at 01:09 AM on 27 July 2012
    Hurricanes aren't linked to global warming
    David Friedman The observation you are commenting on does not imply any sort of perpetual motion machine as the energy that drives the heat engine is ultimately provided externally by the sun. However global warming makes more of the Sun's energy available for the creation and intensification of storms. If the Earth were thermodynamically a closed system, then your argument would have some merit, but it isn't. I would suggest that it is a good idea to refrain from suggeting that others don't understand the science, it is generally better to adopt some humilty and assume that it is you that is wrong, and ask for an explanation of why your objection is incorrect.
  10. David Friedman at 00:59 AM on 27 July 2012
    Hurricanes aren't linked to global warming
    You write: "The background to these enquiries stems from a simple observation: extra heat in the air or the oceans is a form of energy, and storms are driven by such energy. What we do not know is whether we might see more storms as a result of extra energy or, as other researchers believe, the storms may grow more intense, but the number might actually diminish." That sounds plausible, but it is wrong,as should be clear to anyone familiar with basic thermodynamics. A storm is a heat engine--it converts thermal energy into mechanical energy (in the form of winds). A heat engine that converts all the thermal energy it takes in to mechanical energy is what is known as a perpetual motion machine of the second kind. It is impossible because it violates the second law of thermodynamics (entropy), in contrast to a perpetual motion machine of the first kind, which violates the first law (energy conservation). The standard example would be a ship that needed no fuel, because it ran off the heat of the ocean. Actual heat engines absorb thermal energy from a hot source, convert some into mechanical energy, and dump the rest into a colder sink. What determines the amount of mechanical energy they get is not the temperature of the source but the temperature difference between source and sink. So simply raising the temperature of sea and air doesn't make more energy available. You need some mechanism that raises the temperature difference. Hence the argument you offer is wrong (whether the conclusion is wrong I don't know). Either you don't understand the relevant science or you are willing to misrepresent the science in order to provide a simple argument for your conclusion. Your site is supposed to be offering accurate scientific information--the fact that it makes an argument inconsistent with elementary thermodynamics is a reason not to trust other arguments it makes. Sources of information that can be trusted on politically contentious issues are rare and valuable. I'll check back in a few days to see if you are still making the same argument. If you are, you are not such a source.
  11. Tar Sands Oil - An Environmental Disaster
    Tom in QLD or Mr Keystone in AB, all can rightly claim that their share of emissions is "not disastrous". Classic tragedy of the Commons, like Great Stink of London in mid-1800. I'm amazed that people still did not learn anything from that event and after 150y+ still denying (e.g. more than half of REPs in US) the stink.
  12. Climate Change Cluedo: Anthropogenic CO2
    One last input from my site here. What about methanogenesis from landfills, which depletes oxygen? And what is statistical significant, what are we looking for exactly to explain the O2 depletion?
  13. Climate Change Cluedo: Anthropogenic CO2
    "It is important to note that because the fall in O2 concentration is significantly less than that predicted from known combustion of fossil fuels, the uptake of CO2 by photosynthesis must exceed the combustion or decay of modern organic material from either anthropogenic (Land Use Changes) or natural sources." (Off topic snipped)
    Moderator Response: TC: Trunkmonkey, the effect on CO2 on plants is not a subject of this post and consequently, this post is off topic. If you wish to raise a particular point about that subject, or if anyone wishes to respond to this post, you can do so where the discussion is on topic.
  14. Earth hasn't warmed as much as expected
    Well, I see that Sandia issued a press release for at least one of their other climate talks (a good one), so maybe it's just their standard practice, and perhaps it took them a while to summarize Lindzen's talk. So perhaps the press release isn't quite as bad as I initially thought.
  15. Climate Change Cluedo: Anthropogenic CO2
    Chris Machen @27, Wikipedia lists total methane emissions of 600 teragrams per annum, or 600 million tonnes of methane per annum; and 20 terragrams (million tonnes) increment after sinks are taken into account. Compared to the 2008 fossil fuel plus cement emissions of That is less than the 720 million tonnes 8750 million tonnes, that still only represents 7% for total emissions, or 0.2% for net emissions. Of those emissions, those from wetlands (225 Tg/a), termites (20 Tg/a), ruminants (115 Tg/a), waste treatment (25 Tg/a) and biomass burning (40 Tg/a) are all generated from carbon originally removed from the atmosphere by photosynthesis in recent times. As such, the full cycle involves no net change in O2 levels. A further 110 Tg/a comes from fugitive emissions from the fossil fuel industry, and hence are already accounted for as part of total human emissions from fossil fuels. That leaves just 65 of 600 Tg/a that can make an additional contribution to the reduction of O2 levels in the atmosphere. That represents an additional 0.74% O2 reduction from methane emissions. Thus calculated, I can concede the amount is greater than 0.2% - but I certainly cannot see how it could be considered significant. I should note, however, that only clathrates represent emissions of methane which do not derive their carbon from either recent photosynthesis (hence having no net effect) or from fossil fuels (hence already accounted for). Clathrates represent 0.11% of the effect of fossil fuels based on the wikipedia figures.
  16. Earth hasn't warmed as much as expected
    I don't recall hearing that he was coming out here. I was on vacation most of June, so I must have missed the talk - I don't even recall seeing an announcement that he was coming. It's rather disappointing that he would've been allowed a venue at SNL given his recent record, especially after having Dr. Santer out (I think last year). But this is a pretty conservative institution with lots of engineers, so I can see it happening.
  17. Earth hasn't warmed as much as expected
    Hi Dana, Oh dear, Sandia has a lot of explaining to do, because now they are guilty of promulgating misinformation. Worse, it shows that they were uncritical of Lindzen's claims and opinions. I mean for goodness' sakes-- Sandia labs is affiliated with Lockheed Martin and the U.S. Department of Energy’s National Nuclear Security Administration. How on earth can these organizations, organizations who rely so critically on accuracy and robustness, endorse Lindzen's litany of fallacies and misinformation?
  18. Earth hasn't warmed as much as expected
    Albatross - even worse, Sandia issued a press release with Lindzen's misinformation, for some reason a month after the talk happened. That press release was then picked up and Lindzen's misinformation was spread throughout the interwebs to a much larger audience. Inviting Lindzen to talk was a big enough mistake, but then to issue a press release about it? A month after the fact? Bad move, Sandia.
  19. Climate Change Cluedo: Anthropogenic CO2
    Thanks for your input everybody. Though what i meant basically was what Tom points out to me in 26. I checked wiki again and found this "Uncontrolled build-up of methane in Earth's atmosphere is naturally checked—although human influence can upset this natural regulation—by methane's reaction with hydroxyl radicals formed from singlet oxygen atoms and with water vapor." With ozone depletion causes oxygen depletion is the result from the methane -> water vapor - reaction, and then the water vapor in the cold stratosphere destroys ozone. So maybe the ozone destruction doesn't destroy oxygen but it happens before that. However the above quote is from this page http://en.wikipedia.org/wiki/Atmospheric_methane which shows also (Section "Emissions accounting of methane" 1999 numbers?)about a 60 : 40 ratio for anthropogenic contribution to methane sources. (notice rice paddies are listed under natural sources) Emissions + Sinks Imbalance (trend)+20 ~2.78 Tg/(nmol/mol) +7.19 (nmol/mol)/a And further down (Section "Rice agriculture") "crop alone is responsible for approximately 50-100 million metric tons of methane emission each year" So i think the emission of methane are higher than 0.2%. However i do not meant to say this is the only source, just another - and possibly above 0.2%.
  20. Earth hasn't warmed as much as expected
    Unbelievable that Sandia National Labs would even consider entertaining the misinformation from Lindzen or associating themselves with Lindzen who is known for promulgating misinformation. Lindzen's egregious errors and misinformation have been pointed out so many times now, here at SkS and elsewhere, and what does he do? Lindzen simply recycles the same errors and misinformation-- this time to "Sandia National Labs"-- knowing full well that the information in his talks is incorrect and/or misleading. Talk about bringing MIT into disrepute.... Frankly, I find such behaviour by an academic, from MIT of all places, to be horrendous and unacceptable. Dr. Mike Mann was (needlessly) investigated by PSU based on nothing but false allegations and innuendo, he was of course vindicated. Why is Lindzen not being held accountable by MIT when the evidence against him of misconduct is incontrovertible?
  21. Earth hasn't warmed as much as expected
    We're working on a response to that horrid talk, KR. Look for it next week.
  22. Climate Change Cluedo: Anthropogenic CO2
    Chris Machens @13 raises an interesting question. Unfortunately he then diverts into a side issue with a discussion of Ozone, which is essentially irrelevant. All we need to recognize is that methane released to the atmosphere will eventually break down to a CO2 molecule and two H2O molecules, consuming two O2 molecules in the process. As CO2 and H2O are the most chemically stable products of the various reaction pathways between CH4 and O2, we can ignore the details. The question then arises, how significant is the release of methane to the depletion in atmospheric O2? Total methane emissions have raised the methane concentration in the atmosphere by approximately 250 parts per billion since 1978. Given that the atmosphere contains approx 1.8 * 10^20 moles, and the molar mass of methane is 16 grams per mole, that represents emissions of 720 million tonnes of methane. Over approximately the same period, humans have used for energy, or flared over 350,000 million tonnes of methane. Thus emissions of methane represent just 0.2% of human consumption of methane. The figures used are conservative, and do not include the fact that much of the methane emission comes from fugutive emissions (gas leaks) from human energy use which are incorporated in the total human consumption. So, while Chris has identified a genuine additional source of O2 depletion, it is too small relative to human use of gas for energy to be noticeable within error; let alone compared to the total use of fossil fuels, of which gas is a very minor component.
  23. Climate Change Cluedo: Anthropogenic CO2
    Chris Machens @23, to give your quote in context, it reads as follows:
    "4.2.3 HOX catalytic cycles -- The importance of these two species, methane and water vapor, in ozone chemistry is that they transport and release hydrogen into the stratosphere. The activated hydrogen that is released can then participate in the destruction of odd oxygen, i.e., ozone, through a variety of catalytic cycles. These reactive hydrogen (HOX) cycles are summarized by Figure 5.15. The open circles show the predominant species in which hydrogen exists in the stratosphere. We have not included H2 (molecular hydrogen), H2O (water vapor), and CH4 (methane) since they are not involved in the fast stratospheric hydrogen photochemistry balance. The arrows with superimposed boxes are reaction pathways. For example, OH (left circle) reacts with O3 to form HO2. The reaction is written OH + O3 --> HO2 + O2 On the figure, we see this represented by the line with the superimposed blue (O, O3) box. The O2 (molecular oxygen) product is not represented, because it is not a hydrogen species. All of the reactions which lead to ozone creation are colored in blue, while ozone photolysis is colored in magenta. Each water vapor molecule can be transformed into two molecules of HOX (reactive hydrogen) through reaction with O atoms via a reaction of water vapor with the singlet D oxygen atom. H2O + O(1D) --> 2 OH Recall that HOX = OH + HO2. In this case, the reactive hydrogen exists in the form of two liberated OH (hydroxyl radical) molecules which become the catalyst in a pair of reactions with odd oxygen (OX) that result in a net loss of OX, by which we mean a net loss of both ozone molecules and free oxygen atoms. OH + O3 --> HO2 + O2 HO2 + O --> OH + O2 ------------------------- NET: O3 + O --> 2 O2 (See Figure 5.15a) Notice that the NET effect of the reactions is simply a conversion of two odd oxygen molecules into two molecules of O2. The sum of reactive hydrogen, OH + HO2, is conserved by this cycle."
    (Your quote underlined; my bolding) So, in context it is clear that the net reaction to which your refer is the loss of O3 and O and the creation of O2, hardly an explanation for the depletion of O2 from the atmosphere. That section, however, does not refer to section 4.2.2 from which you draw the methane related reactions, so I am unsure why you refer to it, or why Phil drew attention to it.
  24. Climate Change Cluedo: Anthropogenic CO2
    OK. Chris. Let's see: 1) ozone is O3 2) "free oxygen atoms" = O Is there anything we've forgotten? Perhaps O2, commonly referred to as "oxygen"? Does the statement "O3 + O ==> 2O2" show up somewhere?
  25. Tar Sands Oil - An Environmental Disaster
    Clyde@5 In his recent New York Times article, I think that James Hansen's figures for the increase of atmospheric CO2 as a result of complete exploitation of the tar sands are incorrect. He cites a figure of 240 Gt of carbon in the tar sands, which, once combusted, would produce an increase of 120 ppm in the atmospheric concentration of CO2. This assumes that the atmospheric fraction (the percentage of CO2 emitted that stays in the air) would be 100% (today it's about 45%, with the rest of the CO2 going into the ocean and biosphere). Although some people are worried that the atmospheric fraction may increase over the next few decades as the biosphere turns from source to sink, it is very unlikely to rise to 100%. On the other hand, Hansen believes that we have already put too much extra CO2 into the ocean-atmosphere system and that we will have to, some day soon, take it out and sequester it. In that case, using the 100% figure is appropriate for the amount of CO2 that we will have to extract. The 240GtC figure he quoted in the NYT (last year in the Huffington Post he used a figure of 400GtC) is derived from the total bitumen-in-place, not the recoverable bitumen. Current recovery rates are around 50% for the most suitable reservoirs that have been chosen to exploited first and it seems unlikely, even with great improvements in technology, that the recovery rate for the unproven resources, which are located in thinner, deeper or less porous rocks, will exceed 50%. I would say that the 120ppm figure is too high by a factor of two and maybe even a factor of four. Which does not mean that I think developing the tar sands is inconsequential for the climate. On the contrary, an addition of 30-60ppm of CO2 from a single source is a very significant contribution towards the climate disaster that we are busy creating.See my blogpost Alberta’s bitumen sands: “negligible” climate effects, or the “biggest carbon bomb on the planet”? for more detail.
  26. Climate Change Cluedo: Anthropogenic CO2
    I read following this section "In this case, the reactive hydrogen exists in the form of two liberated OH (hydroxyl radical) molecules which become the catalyst in a pair of reactions with odd oxygen (OX) that result in a net loss of OX, by which we mean a net loss of both ozone molecules and free oxygen atoms." Soooo? "..net loss"
  27. 2012 SkS Weekly Digest #29
    Not sure where this should go but your Braganza et al 2004 link is dead in http://www.skepticalscience.com/Empirically-observed-fingerprints-of-anthropogenic-global-warming.html replace it with http://150.229.66.66/staff/jma/2004GL019998.pdf
  28. Climate Change Cluedo: Anthropogenic CO2
    Chris Machens, You also need to read section 4.2.3 of the document you linked to.
  29. Climate Change Cluedo: Anthropogenic CO2
    Phil "methane water vapor oxygen depletion atmosphere" This article describes the chemical reaction better: methane reacting with something called the singlet D oxygen atom, denoted O(1D). This is a free oxygen atom that is in a particular sort of excited state. The reaction is CH4 + O(1D) --> CH3 + OH The result is a hydroxyl radical and a leftover methyl radical (CH3), which quickly reacts via CH3 + O2 + M --> CH3O2 + M CH3O2 + NO --> CH3O + NO2 CH3O + O2 --> HCHO + HO2 Eventually, reactions of HCHO (formaldehyde) with the hydroxyl radical result in the production of another water vapor molecule in the region between 35 and 45-km HCHO + OH --> CHO + H2O http://www.ccpo.odu.edu/~lizsmith/SEES/ozone/class/Chap_5/5_4.htm
    Moderator Response: TC: Link made live.
  30. Tar Sands Oil - An Environmental Disaster
    Further to Dana @6, Hansen is on record as saying that one way to tackle global warming is to never build another coal fired power station, and to phase out all existing coal stations by the end of their design life. He also adds a simultaneous fee and per capita dividend carbon tax. The idea is that by preventing the use of all coal reserves we prevent the burning of sufficient fossil fuels to exceed the 1.5 degree C limit he considers to be the safe limit on temperature increase. Clearly, following this logic he would oppose the opening of new coal mines in my home state of Queensland (Australia), even though all Qld reverves by themselves are no where near enough to take us over that limit. The logic is that what we (Queenslanders) permit ourselves to do, we cannot object to in others; and if others equally exploit their coal reserves we are heading for a 5 degree plus world. The same logic applies to tar sands. Even if the Alberta tar sands are not by themselves enough to bring on disaster, exploiting them tacitly encourages the exploitation of all tar sands, which would be disasterous. I consider the logic to be impeccable, regardless of the merits of any of Hansen's other claims about those tar sands.
  31. Robert Marston at 07:03 AM on 26 July 2012
    Tar Sands Oil - An Environmental Disaster
    I think it's more an issue of going for the unconventional fuels. If we add tar sands, tight oil, oil shale, tight gas, methane hydrates, ultra deep water oil, and unconventional coal, we're on a road to increasing carbon emissions through at least 2030. You can't hit 2 degrees C in a scenario like that. Not by a long shot. Last year, the world emitted 31.6 billion metric tons of CO2, 3.2 percent more than the previous year. Fatih Birol: "When I look at this data, the trend is perfectly in line with a temperature increase of 6 degrees Celsius (by 2050), which would have devastating consequences for the planet." At the current growth rate, we're set to hit the trillion ton limit by around 2030 or even before. Much of the growth in fossil fuel use is coming from unconventional fuels like tar sands and since the extraction and enrichment process for tar sands is very similar to oil shale (which is a much, much larger resource), it's really critical we stuff that genie back in the bottle ASAP.
  32. Climate Change Cluedo: Anthropogenic CO2
    Chris@...multiples: It *generally* does not look very good, to contantly cite Wikipedia as a *primary* source of data. Nothing wrong with using it here and there but in addition to your dodging Sphaerica's direct questions, I would think you'd use more academic sources to back up what you posit.
  33. Climate Change Cluedo: Anthropogenic CO2
    Because the process of ozone depletion causes oxygen depletion. This statement is incorrect. Ozone depletion produces oxygen, as the wikipedia articles referenced describe.
  34. Tar Sands Oil - An Environmental Disaster
    Clyde, I think we're in agreement with Hansen, who says
    "If we turn to these dirtiest of fuels, instead of finding ways to phase out our addiction to fossil fuels, there is no hope of keeping carbon concentrations below 500 p.p.m....weneed to start reducing emissions significantly, not create new ways to increase them"
    That's what we said in the above post. However, the amount of carbon which will be released by exploiting the tar sands is still not a climate catastrophe-causing quantity of carbon emissions. The problem is in the approach that we would be taking, exploiting unconventional fossil fuel sources rather than leaving as much carbon in the ground as possible. It represents taking the completely wrong approach, but just by the numbers, the tar sands emissions by themselves aren't going to mean the difference between catastrophe and non-catastrophe.
  35. Earth's five mass extinction events
    Geologista@68: Chances are you are long gone, and may not respond but just in case you may actually get word of this...this "geologita" would like you to provide definitive support, in the form of peer-reviewed sources, that back up your *highly* dogmatic assertion. "7)When looking at the fragility of reef systems and the oceans biomass natural and man-made hazards have impacted their growth and health but NOT FROM CO2." I will be astonished when/if you do/can.
    Moderator Response: [DB] Geologista has indeed not commented here since.
  36. Climate Change Cluedo: Anthropogenic CO2
    Sphaerica: "Why did you change topics to ozone?" Because the process of ozone depletion causes oxygen depletion. http://en.wikipedia.org/wiki/Ozone-oxygen_cycle http://en.wikipedia.org/wiki/Ozone_depletion
  37. Tar Sands Oil - An Environmental Disaster
    This is not a climate catastrophe-causing quantity of carbon emissions James Hansen disagrees. If Canada proceeds, and we do nothing, it will be game over for the climate. Read more here.
  38. Earth hasn't warmed as much as expected
    Lindzen is still pushing his nonsense, this time in a talk at Sandia labs. WUWT is echoing it as well. Points refuted a thousand times...
  39. Bob Lacatena at 03:29 AM on 26 July 2012
    Climate Change Cluedo: Anthropogenic CO2
    15, 16, Chris, Why did you change topics to ozone? We were discussing O2 depletion in the entire atmosphere, and I presume (because we are on the topic of this post) as an indicator of an anthropogenic cause of CO2 increase. Any casual reader of your comment is going to interpret it in that fashion, and your comment suggests oxygen depletion is not an indicator of an anthropogenic source of CO2 increase. As such, you need to support the claim. Your shift to ozone depletion has no bearing whatsoever on the matter, and dodges the point. Your explanation of the chemistry is similarly irrelevant. I well understand the reaction, and anyone who doesn't can google it quickly enough. But you still haven't provided the necessary foundation for your argument, which is observational and computational evidence not merely that the reaction occurs (as it does naturally and continuously), but also that the mass balance involved, as compared to fossil fuel combustion, is high enough to diminish the argument in the original post. You've failed to do so. I'll give you a second chance, or dismiss your statement as unsubstantiated noise.
  40. Climate Change Cluedo: Anthropogenic CO2
    And the reaction Shindell mentions, includes Oxygen. methane's reaction with hydroxyl radicals formed from singlet oxygen atoms and with water vapor. http://en.wikipedia.org/wiki/Methane
  41. Climate Change Cluedo: Anthropogenic CO2
    Re 14 Sphaerica Observations of ozone show a thinning of the Earth's protective stratospheric ozone layer by about 3 to 8% overall since the 1970s. In the upper stratosphere, ozone depletion has been from 15 to 20%. Again, the model is better able to reproduce these values when increased water vapor is included. This is especially true in the upper stratosphere, where ozone is most sensitive to water. The model indicates that increased water vapor accounts for about 40% of the ozone loss in the upper stratosphere, and about 20% of the overall loss to date. There are two driving forces behind the change in stratospheric moisture. Increasing emissions of methane are transformed into water in the stratosphere by chemical reactions. This can account for about a third of the observed increase in moisture there. http://www.giss.nasa.gov/research/briefs/shindell_05/
  42. Bob Lacatena at 01:30 AM on 26 July 2012
    Climate Change Cluedo: Anthropogenic CO2
    Chris, Do you have a citation for your Oxygen Depletion understanding... one complete with actual numbers? Nothing is ever "just this one cause," and the conversion of CH4 + O2 to CO2 and H2O is an ongoing natural process that gets H2O into the upper atmosphere. The question becomes one of simple math... how much O2 does the increase in the amount of CH4 (presumably from anthropogenic sources) consume, and how does this compare with the total oxygen depletion. Without those numbers, and a citation, your statement is pure speculation. But I strongly doubt that the numbers balance, or that fossil fuel combustion fails to dwarf the upper atmosphere methane contribution.
  43. New research special - satellite measurement papers 2010-2011
    Record Greenland Ice Melt
    Moderator Response: [RH] In the future you should try to include more context rather than post a link only comment.
  44. Tar Sands Oil - An Environmental Disaster
    82% higher (broken link)
  45. Climate Change Cluedo: Anthropogenic CO2
    As i understand the Oxygen Depletion is attributed to greenhouses gases like Methane breaking down in the upper atmosphere and this reaction consumes O2 molecules. On another note (-Snip-)
    Moderator Response: [DB] As an FYI: promoting awareness of research tangential to the OP is acceptable; promoting your blog is not. Self-promotional link snipped.
  46. Tar Sands Oil - An Environmental Disaster
    Thanks dana
  47. Tar Sands Oil - An Environmental Disaster
    mandas - McKibben's number is from now to 2050, whereas the Aussie Climate Commmission was 2000 to 2050. We've already emitted 328 Gt, bringing the remaining budget down to 672 Gt. McKibben also uses an 80% probability of limiting to 2°C vs. the Climate Commission's 75%. Not sure what accounts for the rest of the discrepancy, but it's not an exact calculation.
  48. Tar Sands Oil - An Environmental Disaster
    I am interested in the number from the Australian Climate Commission's The Critical Decade report that humanity has a budget of 1 trillion tonnes of CO2 between 2000 and 2050 to have a probability of about 75% of limiting global warming to 2°C or less. I read the piece by Bill McKibben in Rolling Stone last week which quoted a figure of 565 gigatonnes to stay below a 2 degree increase - which is only half the ACC figure. I would be interested to see the basis for both of these numbers, and an explanation for the discrepancy.
  49. New research special - satellite measurement papers 2010-2011
    Note also that the Sorenson paper linked in the Cryosphere list uses altimetry for ice change. Dome is positive is anything.
  50. New research special - satellite measurement papers 2010-2011
    Paul, I dont know. It might not be falling at all (depends on amount of winter accumulation) but do you expect much change? The GRACE maps of mass loss show most of the losses around the edges (as you would expect).

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