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  1. “Not every housewife is aware of the environmental consequences of the use of shale gas…I don’t know who would take the risk of endangering drinking water reservoirs.”—Alexander Medvedev, Director-General of Russia’s Gazprom Export (Reputed former KGB offier)

    Gazprom has expressed not-very-sincere environmental concerns about fracking and has been watching the EPA study this issue.

    This is right in the media, so you can actually see what they are doing.

    Of course, Gazprom has “gone green” on this issue because they want to sell liquified natural gas in America.

    I wondered what is worse environmentally: fracking or buying Russian natural gas. If you buy their gas, they tend to buy up your politicians–that has already happened in Europe.

    I would rather put a lot of money into renewables.

    Comment by Snapple — 16 Apr 2011 @ 12:29 PM

  2. Re 1, Snapple,

    I think you are almost on the right track here, but not quite.

    I would say that Medvedev is happy to discourage production of shale gas in Europe and America so that their already abundant output will be more valuable.

    Comment by Jim Bullis, Miastrada Company — 16 Apr 2011 @ 1:13 PM

  3. I’m an oil industry geoscientist, so you may find that my “commentary [serves] to bolster [my] prior position…” (not sure why you’d expect anything else — that’s kind of the point of making a comment!) But I just wanted to say that I was surprised the authors don’t mention flaring at all. The practice of burning vented gas is obviously not a great way to deal with the problem, but at least it reduces the emissions to (more or less) what they would have been if the gas had made it to the consumer. From other things I read, this for example, admittedly from industry advocates, but still data, it looks like a lot of gas is generally captured and flared. As you can imagine, venting a lot of methane near a wellsite is rather dangerous, so I think the industry tries to capture it for flaring. I could be wrong, but it just struck me as a bit of an omission, since the paper does not mention it.

    Comment by Matt Hall — 16 Apr 2011 @ 1:46 PM

  4. I’m going to preface this comment by saying that the oil and gas industry has earned every bit of the public’s skepticism when they claim something is clean or green. No doubt about it, if they told me my house was on fire and I turned to see smoke and flames, I’d still be a bit skeptical. Let me also say that the Energy in Depth article, while it gets some technical points right, is a bad stab at communication — it reads childish and vindictive and certainly does not help produce any useful dialog.

    But, like I’ve said elsewhere, the Howarth estimate is probably significantly inflated.

    Flowback gas from shale wells is flared, not vented, and, while the CO2 has its footprint, it’s not nearly as high as the methane’s. Further, Howarth’s estimates for venting during drilling out plugs originates from tight gas wells, not shale gas, and tight-gas is treated very differently from shale-gas wells as to when they drill out plugs (in shale wells, plugs get drilled out before flowback begins and there’s very little gas in the well at that point).

    This probably more than doubles the direct emissions of methane during flowback in Howarth et al’s low case and shrinks their high case down by 20% and maybe more. The problem is that none of the authors really have a grasp on the operational side of the oil and gas business (two biologists and a civil engineer who specializes in fracture propagation — Ingraffea is no doubt a really brilliant guy with some experience in the oil and gas business, but it’s a real stretch to consider him an expert in energy systems). They based their estimates on a EPA 2010 report, but that 2010 report is based on 2007 and earlier data and alot has changed since 2007. Low-flow wells, like CBM and tight sands, yes, have a history of having their gas vented during flowback, as is indicated in the EPA study. However, shale wells, because they produce like gangbusters, have their flowback gas flared, otherwise, it can become a complete disaster (for example, please see BP Macondo disaster for what happens to “vented” methane around diesel engines).

    It’s not a particularly big surprise that this mistake was made considering the lack of experience and understanding of oil and gas operations, especially some context about what’s changed from 2007 to 2010 and 2011. It can also be considered a parallel to flawed analyses made by non-expert climate-change deniers.

    As for the high case, the estimate of leaked gas from pipelines and compressor stations is probably unrealistic given that more gas is being produced and then consumed within the local region rather than imported over long distances (a shorter distance of pipeline travel means fewer places for it to leak — for example, less gas has to flow 1500 km from Canada and only needs to flow a few hundred km from Pennsylvania to NY State).

    Now, I do agree that there needs to be a better demonstration of the risks (although, there are many, many studies on conventional gas, just not much in the way that’s included unconventional). Using a higher GWP for methane than in IPCC (2007) is reasonable. But I’d prefer any study get done by somebody like Paulina Jaramillo, who has a good background in this kind of stuff or somebody else with experience, so that potential problems with the data can be foreseen and dealt with appropriately. Hopefully, a study like Howarth et al’s gets more going in the pipeline (yuk yuk) if only to refute it. Further, hopefully it gets companies to release some real data, a real constraint on doing these kinds of analyses (I really sympathize with Howarth and how scant the data is to use on something like this). The industry says they want policy made on science but all so often refuse to submit any. Well, it’s time to cough it up if they want to be taken seriously. Until then, the EPA a number is a decent, even if it might be a bit low, start.

    Again, it’s not that I have great love for the oil and gas industry, because I don’t. They create most of their own messes and then deny until the lawyers pay up in lawsuits or buy politicians. I just like good analyses, and I doubt this is one of them.

    Comment by Miguelito — 16 Apr 2011 @ 2:42 PM

  5. RE: “One would think that the overwhelming consensus that there are no panaceas for decarbonising our energy supply . . .”

    Dear Sir:
    While I am respectful of your science acumen and know this site to be a valuable contribution to the study of climate science, your framing of such statements as the above hamper your ultimate understanding. After a lifetime of studying technology and policy I content that your statement as read is patently false. In point of information, there is a vast literature asserting the opposite.

    One might start by speaking truth. If we may categorize all known physical phenomena on earth as either matter or energy, then lithosphere carbon, which exists in the solid, gas or liquid state, is a form of Matter, not Energy. Thus, petroleum is not “energy supply” but a “material,” a resource of matter. Statements about “decarbonizing energy” or even “stored energy,” rather than “stored matter,” become a bit “Alice Through The Looking Glass,” if you will.

    Humans may be counting global “energy” at the rate of some 16 TW, yet the sun’s energy delivered at the planet’s surface is some 12,000 TW.

    Kind regards, JRN

    Comment by James Newberry — 16 Apr 2011 @ 3:07 PM

  6. \there are no panaceas for decarbonising our energy supply might have at least started to make a little impact on the media. Any real policy initiative will have complex effects, and while scientists can certainly help quantify them, nothing at the scale we require is going to be completely neutral in all particulars\

    Yes. Thank you. That is very difficult for the media because:

    1. Journalism school does not require mathematics or science.
    2. The average public didn’t go to college and took only the minimum courses to graduate from high school.
    3. Ditto for politicians.
    4. None of the above 3 groups understands that we really mean what we say. \The end of civilization in the 2050s\ is not hype and we really can predict it. Our inability to predict the stock market is irrelevant.
    5. An energy source that works well in one area does not necessarily work well, or at all, in another area. It is best to let the engineers do the engineering.

    The federal government should limit the CO2 + equivalent per kilowatt hour, not specify the source of the energy. Specifying the source leads to gridlock rather than action.

    Comment by Edward Greisch — 16 Apr 2011 @ 4:04 PM

  7. I would second Miguelito’s comments above @4. Well said.

    It seems odd to me that the gas industry is not more punctilious about accounting for gas volumes between wellheads and burner tips. If it were money that went missing in this way then shareholders, regulators and, maybe, the police would show concern. (What’s especially odd is that for gas companies methane actually is money.) Fugitive gas can also amount to fugitive resource royalties in some jurisdictions, so even climate-skeptic citizens should be concerned.

    A certain \auditor\ has recently demanded an engineering-level study on climate sensitivity. Perhaps it’s only fitting that Howarth et al are demonstrating the need for a science-level survey of industrial engineering practices.

    Comment by Andy S — 16 Apr 2011 @ 4:14 PM

  8. Gavin,

    My take (in the post you cited) is that there is a schizophrenic quality to the media coverage of natural gas. To a large extent, I think this reflects the ambivalence (split?) in the climate/environmental community with respect to natural gas as a “bridge” fuel. That’s the point I was trying to get across.

    Ironically, the dichotomy you mention was on ample display this week, during much of the coverage of the Cornell shale gas study. For the most part, the media parroted the conclusions drawn by Howarth et al. In another post, I discuss that coverage here:

    Comment by Keith Kloor — 16 Apr 2011 @ 4:45 PM

  9. Aside from fugitive emissions natural gas still has a couple of major problems. When burned in power plants the CO2 emissions are 45%-75% that of coal for similar electrical output. Long run it won’t get us to say 80% CO2 reductions. Natural gas is currently needed to balance the variable output of all the wind and solar plants that have been spurred by subsidies and mandates. What happens when gas runs out? Alternative fast response electricity sources like hydro may also be limited.

    I make it three strikes against natural gas; still high CO2 when burned, looming failure of co-dependent intermittent energy sources and now fugitive emissions. I think we need to ration natural gas supplies for a century not use it all in just decades. If done right we could get lower rates of CH4 and CO2 with more sustainable energy generation.

    Comment by Johnno — 16 Apr 2011 @ 4:46 PM

  10. I’d like to point back to David Archer’s “Methane Hydrates & GW” at

    Altho it’s about melting hydrates, it points to the compounding effect of fast release of CH4: if there are huge releases within a 10 year period (whatever the source) the effect would be greater, than a slower release over, say, 100 years.

    Also, I think someone’s pilot light just went off …..

    Luckily I get a type of “gas” headache whenever there’s a gas leak, so when we had a home with gas energy, I always knew when the pilot light went off, even when there was a tiny leak in the garage (while it took the gas man an hour of searching all over — doubting me all the time — to finally find it with his detector).

    If people would only use their heads…

    Comment by Lynn Vincentnatnathan — 16 Apr 2011 @ 8:50 PM

  11. Johnno @9 — Here in the Pacific Northwest the ~3.3 nameplate GW of wind generators are currently backed by our extensive hydro capacity. It appears that future wind generation will mostly be backed by fossil fuel fired generators.

    Comment by David B. Benson — 16 Apr 2011 @ 8:53 PM

  12. Apparently, natural gas must either be perfect solve-all or worse than useless (see for instance, Keith Kloor’s take).
    Worse than useless does seem right for the long term. We need to stop using natural gas almost as badly as we need to get off coal. What we don’t need is more solar or wind than we can handle without natural gas backup.

    Comment by Greg Simpson — 16 Apr 2011 @ 8:59 PM

  13. Nice Battlestar Galactica Reference.

    Comment by Reed Maxwell — 16 Apr 2011 @ 9:03 PM

  14. The political solution to reducing methane leakage during production and transport is to create incentives for companies to improve their pipeline stock. Many companies forego needed capital investment to improve their cash positions and potential shareholder return. Global governments (partially controlled by oil/gas lobbies) have no intention on changing incentive programs for the oil and gas industry. Until incentives change, “science” has no hope of reducing climate forcing related to methane production.

    Comment by Lloyd Smith — 16 Apr 2011 @ 9:10 PM

  15. I have no idea how the science re:the Howarth paper will sort itself out (to borrow a phrase from economics), but even in the optimal case — the conclusion is incorrect and greatly overstates the impact of fracking — NG is still a terrible idea.

    Replacing gasoline in vehicles with CNG only results in a reduction in CO2 emissions of about 20 to 25%, conspicuously at odds with NG’s image as a “clean” fuel. (If CO2 were dark gray and smelled really bad, fighting climate change would be dramatically easier.)

    And as someone pointed out above, NG provides nowhere near the CO2 reduction, compared to coal, that we need. Building NG plants with a 40 to 60 year operating lifetime would provide a short-term move in the right direction, but in a decade or two those plants would help strand a country like the US above the required emissions curve.

    Thanks, Gavin, for an interesting and informative post on a critical topic.

    Comment by Lou Grinzo — 16 Apr 2011 @ 9:55 PM

  16. According to filmmaker Josh Fox, fracked gas costs 20 percent more than coal in energy spent or something to that effect. He produced the oscar nominated film, Gasland. My current novel concerns gas drilling and hydro-fracturing.

    Comment by Mark A. York — 17 Apr 2011 @ 12:09 AM

  17. The answer to some of the issues raised @11 and @12 is large scale solar thermal base load power with heat storage.

    Here’s a how a 1250MW CSP plant with 3.5 hours molten salt heat storage would operate in Nevada in mid-summer. Winter operation would be similar but at lower output.

    The plant would start saving heat at sunrise. A few hours later, it would start generating electricity and continue storing heat in the salt. By 1pm when the sun peaks, it would be at full rated power, 1250 MW. It would continue to put out at least it’s full rated power, while increasing output and peaking at about 3,000 MW at 5pm, exactly when demand in the grid peaks in the southwest. It would continue putting out steady but declining power until midnight.
    No power fluctuation when clouds pass by.

    Cloudy periods, which are rare in the southwest can be planned for by the plant manager and utility, from weather forecasts. In the daytime in what the NREL calls Premium Solar Resource areas, there is sunshine all but about 4% of the time.

    3.5 hours heat storage means enough to provide 3.5 hours at full rated power, without any input from the sun.

    The first plant with molten salt heat storage in the U.S. is being built in Arizona. It will have 6 hours heat storage.

    A solar thermal plant can adjust power output to meet demand. Lots of excess wind energy in the grid? A CSP plant can hold off on power generation, saving heat in the salts and dispatch it later when it’s needed. The most versatile of all our renewable energy choices.

    A company called Shec Energy has developed what appears to be disruptive technology for solar thermal. CSP plants of their design would run at twice the temperature of current solar thermal plants. 800-900 C verses about 450 C. And they can store heat at that temperature.

    Comment by frflyer — 17 Apr 2011 @ 12:28 AM

  18. The main gut of this article is that the jury is out. As so it will be for a long time.

    Same goes for the question whether or not electric cars are a net benefit in our attempts to combat climate change. Much controversy. And so there will be for a long time.

    Any attempts to use alternative fuels or alternative technologies to try to maintain our consumer lifestyles are underpinned by many competing processes. Though the devotees of each technology find this laggard science frustrating, there’s not much point doing things that in the end only serve to worsen the situation.

    And that brings us to an obvious conclusion, virtually any technology or behaviour changes that reduces energy consumption has much clearer signals as to its effectiveness. To save a kwh is almost invariably worthwhile doing. To produce a kwh of energy, by whatever means, invariably is a less worthwhile enterprise, because there are always significant hidden costs associated with energy production – whether that be bird strike on wind turbines or fugitive emissions from coal seam gas.

    Motto: Always look to abatement measures as first priority, and only then look to alternative means of production.

    Comment by Chris Harries — 17 Apr 2011 @ 1:30 AM

  19. Some unlikely sources of criticism of Howarth; including MIT, NRDC, Council for Foreign Relations and Clean Air Task Force:

    Posted April 13th, 2011 by Dave McCabe, atmospheric scientist

    • “This paper is selective in its use of some very questionable data and too readily ignores or dismisses available data that would change its conclusions.”

    • “The authors’ choice as to which data to use for leaks from natural gas processing, transmission, and storage systems is also a big concern. They recognize the limitations of EPA data, then use those limitations to dismiss the EPA work, and then use higher values, which come from even more questionable sources. … These two decisions alone result in unrealistically high emissions.”

    Full post:

    Posted April 12, 2011 by NRDC’s Dan Lashof

    • “While these higher figures were produced by well respected researchers, they have not yet been subject to the level of review and scrutiny conducted by the IPCC for its estimates.”

    • “[W]hile I can see an argument for using a time horizon shorter than 100 years, I personally believe that the 20-year GWP is too short a period to be appropriate for policy analysis because it discounts the future too heavily.”

    • “Relatively few actual observations were used to estimate ‘emission factors,’ which were then extrapolated to estimate emissions from the system as a whole.”

    Full post:

    Posted April 15, 2011 by CFR’s Michael A. Levi

    • “The data for leakage from well completions and pipelines, which is where [Howarth] is finding most of his methane leaks, is really bad.”

    • “Howarth’s gas-to-coal comparisons are all done on a per energy unit basis. That means that he compares the amount of emissions involved in producing a gigajoule of coal with the amount involved in producing a gigajoule of gas. … The per kWh comparison is the correct one, but Howarth doesn’t do it. This is an unforgivable methodological flaw …”

    • “I worry about what this paper says about the peer review process and the way the press treats it. … These reviewers don’t appear to have been on the ball. Alas, this sort of thing is inevitable in academic publishing. It’s a useful caution, though, against treating peer review as a mark of infallibility … “

    Full post:

    MIT Energy Initiative exec. director Melanie Kenderdine, interviewed by CNBC on April 12, 2011

    • “What he has done in his analysis is deviated from what are accepted standards, accepted by EPA, DOE, the IPCC, European Trading Scheme, California Air Resources board, where essentially the denominator that they use to calculate the impacts of various greenhouse gases is an agreed upon 100 years; Professor Howarth uses 20 years.”

    • “[T]here are major scientific organizations that think we should actually extend that hundred-year period, not shorten it. So he has changed what is a standard number for calculating the impacts of greenhouse gas emissions … “

    Full segment:

    [Response: I think the comment by Melanie Kenderdine is especially important. Howarth has inflated the impact of leakage by using an inappropriately short window for computing GWP. As Kenderdine notes, just because a lot of policymakers seem to have settled on 100 years as a window, there's nothing magic about that number. Many of us feel (see my post linked by Gavin above) that because of the very long lifetime of the warming caused by CO2, anything short of a thousand years is ridiculous. I'm quite sure that if a thousand year window were used for GWP, then Howarth's case would go away even if his leakage figures were correct. I need to run the numbers, though. If they look interesting I'll do a short update post on how the frakking issue relates to the methane vs. CO2 lifetime dialog. --raypierre]

    Comment by Les Johnson — 17 Apr 2011 @ 7:09 AM

  20. RE #3 & flaring. Hi Matt, I’ve seen flaring in various places. I was just wondering if it might be feasible to turn that flaring into useful energy — accomplish some task, transmit it into the grid, or into ? batteries ?

    Comment by Lynn Vincentnatnathan — 17 Apr 2011 @ 7:16 AM

  21. One can falsify Howarth’s paper, simply by looking at the atmospheric methane concentrations over the years.

    While it is rising again, it was flat, or even declining, for over a decade; over this same decade,global gas production increased 25%. If gas was indeed leaking at the rates Howarth used, then atmospheric CH4 would NOT have flattened.

    OH chemistry changing to clean out CH4? Nope. It is, and has been stable.

    One should also look at the economics of gas leakage. Global gas production is about 3 trillion M3 per year.

    At $4 per 1000 cuft, that would be about 13 billion per year just wasted. At the higher prices we saw in 2005-2008, it would be 30 to 40 billion dollars per year lost.

    I don’t think any company would have this in their business model.

    Comment by Les Johnson — 17 Apr 2011 @ 7:21 AM

  22. Lets do the math:

    According to Wiki, the atmosphere is about 4.2 billion billion m3. The IEA says about 3 trillion m3 of gas is produced each year. Howarth says about 3% of that leaks, or about 90 billion m3 of CH4.

    Cancel the billions, and we have 90 m3 of CH4 per 4.2 billion m3 of air, or 21.4 ppb per year.

    The last few years, CH4 has gone up by 6 to 8 ppb per year, depending on the author. Before that, it was zero, or less, for more than a decade.

    In other words, using empirical data, we can suggest that actual CH4 leakage from gas wells is negligible, and nowhere near the value used by Howarth.

    [Response: The budget for methane is complicated given the various sources (irrigation, landfills, fugitive emissions from all sources, agriculture etc. - as well as all the natural sources). So without a good control on all the others time histories, it is very difficult to constrain any one specific source based on the annual changes. It is not inconceivable that the increase in shale gas exploration in the last 5 years has contributed to the recent upticks, but very hard to prove. - gavin]

    Comment by Les Johnson — 17 Apr 2011 @ 9:00 AM

  23. I am interested on your take on two recent papers that discuss \peak coal\. While not exactly on target with this post, they are certainly related. The two articles are: International Journal of Coal Geology, volume 85 (2011), pp. 23-33 (DavidRutledgeCoalGeology.pdf) and Patzek+and+Croft+2010+-+Peak+Coal+2011.pdf which is in Energy, Vol 35, pp.3109-3122 (2010). Thanks in advance.

    Comment by Jerry Unruh — 17 Apr 2011 @ 10:04 AM

  24. To #2: at the end of the day, we can sum this subject up by saying everything is money related. Governments don’t really care about the environment if it hit their pocket too much.

    Comment by Josh Verienes — 17 Apr 2011 @ 10:46 AM

  25. Gavin: Its very easy to prove. Gas production increased 25% over the period that methane levels were flat. If gas did indeed leak at the rates suggested by Howarth, then we would have seen methane levels increasing by a similar rate as production.

    If you are adding more methane to the mix, and the scrubbing mechanism is the same, then the methane should increase. It didn’t increase, for a decade. Only if the drop in natural production EXACTLY matched the increased Anthro CH4, would you get a flat line. How likely, year after year?

    Empirically, if gas leaked at the rates suggested by Howarth, then methane levels should be increasing by 21 ppb every year. It would be even more in the NH, as the vast majority of gas is produced in the NH.

    Until you can a find a way scrub that 21 ppb without OH chemistry, there is no way that 90 billion m3 of gas will leak every year, and not increase atmospheric CH4.

    Either there is an unknown scrubbing agent; or natural variation EXACTLY matched man made increases; or there is negligible leakage.

    Occam’s razor.

    [Response: You are assuming that all other sources are flat. They are not. There are changes in agricultural emissions, changes in natural emissions (as a function of rainfall/temperature patterns), ongoing efforts to capture methane from landfills, reduce other fugitive emissions (i.e. from conventional pipelines etc.). All I am saying is that a top-down constraint on any individual source is non-trivial. - gavin]

    Comment by Les Johnson — 17 Apr 2011 @ 11:20 AM

  26. @20

    Really hard to do in this case, because the flaring will only happen for a few days (maybe up to a week) during the flowback. Longer term well tests (where pipeline infrastructure is not present to flow into) would be more of a possibility, but it probably won’t happen because it’s an extra cost for a commodity like electricity which isn’t in much demand on a wellsite and difficult to hook up to the local grid.

    Comment by Miguelito — 17 Apr 2011 @ 11:20 AM

  27. Hi, Lynn (#20), re: energy from flaring,

    Better capture as much of the gas as possible and put it to good use in the right place. Recovering energy from big flames coming out of the ground won’t be efficient.

    Comment by CM — 17 Apr 2011 @ 11:36 AM

  28. gavin: your

    It is not inconceivable that the increase in shale gas exploration in the last 5 years has contributed to the recent upticks, but very hard to prove.

    Nope. While shale gas activity may have increased, total gas production over the last few years is relatively flat, at about 3000 billion m3 per year. It even fell the last year of full records.

    2006-2880.2 2007-2954.7 2008-3060.8 2009-2987.0

    Increases in production in the US were more than offset by decreases in Russia and Turkmenistan.

    The decade prior, though, saw large increases in production, but flat methane levels. The last few years has seen flat production, but increasing methane. The two indicators are not moving together and haven’t for 15 years; ergo, they are not closely linked; ergo, there is negligible leakage.

    Granted, there can be some unknown mechanism involved, but its unlikely, especially at the leakage rates proposed by Howarth. That much leakage would have to show up in methane levels.

    Comment by Les Johnson — 17 Apr 2011 @ 11:52 AM

  29. Re: Flaring 45% of gas prodution in Russia

    “In August 2007, the then President Vladimir Putin set 2011 as a deadline for Russia to reduce flaring to 5 percent of the country’s associated gas production from the current 45 percent. However, in December 2008 Russian Natural Resources Minister Yuri Trutnev said that the deadline had been pushed back to 2014 (Interfax, December 4, 2008), but declined to specify any reason for the delay.”

    Comment by Snapple — 17 Apr 2011 @ 12:35 PM

  30. Good post.

    21, 22, Les Johnson and Gavin: isn’t it likely, on present data, that ground water pollution is a bigger problem with frakking than atmospheric pollution? That’s no criticism: the paper addressed a real problem and this site is dedicated to real climate; I’m just asking.

    Comment by Septic Matthew — 17 Apr 2011 @ 2:55 PM

  31. Snapple: they are flaring 45% of the associated gas produced WITH oil. Gas wells would not need to be flared. Oil wells need to be flared to get rid the gas, as it can interfere with oil surface gathering equipment. This is common in developing countries, like Russia and Nigeria. But, even Nigeria is moving away from the practice.

    It used to be common in North America, but is rare nowadays.

    Note that flaring is actually burning of gas, so while CO2 is produced, the GHG effect is still much less than raw gas.

    Comment by Les Johnson — 17 Apr 2011 @ 2:58 PM

  32. I think that the stupidest thing that I’ve heard of while monitoring this debate over the last few years, is the idea of using Fraking – or of extracting Natural Gas at all! – from the Yellowstone Basin (i.e.: Caldera).
    As I pointed out in a heated letter to the DOE, DOI, my Congresspeople, etc., Volcanoes are delicate things that erupt because a decrease in the PRESSURE holding back the Magma back; like that which MIGHT occur, IF you start extracting the gas/water from the shale overburden; causes a sudden ‘opening a shaken up pop can’ effect in which the Gases in the Magma suddenly come out of solution in a most violent way.
    I also pointed out that Yellowstone is due to erupt at any moment.
    Hey! At least if it does, we won’t have to worry so much about how badly we’ve been messing up the Environment, eh?

    Comment by James Staples — 17 Apr 2011 @ 5:10 PM

  33. Les,

    Ok. That makes more sense.

    Comment by Snapple — 17 Apr 2011 @ 6:01 PM

  34. I’m quite curious about the potential for methane to be a significant precursor to ozone, as I only just found studies indicating it has a role, and so I recently posted this:

    [With respect to methane as an under-appreciated precursor to ozone, I note parenthetically this new study, which concludes "...that shale gas developed through fracking carries a higher greenhouse gas footprint because the “fugitive” methane emissions at the fracking sites are greater than releases from conventional gas wells." and recommend the movie Gasland where the infrared images of escaped methane are shocking. I expect it would be simple to find more along the lines of this ominous snippet: "Major sink of methane is its reaction with OH leading to the formation of ozone." or this one: "Methane, a VOC whose atmospheric concentration has increased tremendously during the last century, contributes to ozone formation but on a global scale rather than in local or regional photochemical smog episodes. In situations where this exclusion of methane from the VOC group of substances is not obvious, the term Non-Methane VOC NMVOC is often used."]

    the links can be found here

    Any thoughts as to the role of methane or other emissions are welcome because I’d really like to understand
    [edit - let's not get started on that again, thanks]

    Comment by Gail — 17 Apr 2011 @ 7:26 PM

  35. I thing, therefore I are.

    Comment by Gail — 17 Apr 2011 @ 8:32 PM

  36. 28 Les Johnson: Just wondering: Does a valve leak more when it is partly closed than it does when it is fully open? I’m thinking a partly closed valve would have more internal pressure than a fully open valve.

    What is “flowback”?

    Well casing gas: What is it and how does it flow through solid concrete? Or could somebody explain this stuff please?

    32 James Staples: Is there a problem with using high temperature geothermal energy from Yellowstone? Is it possible to cool the magma by doing so, and would this prevent the eruption or hasten it?

    Is there a way to “open the pop can” very slowly to get a Hawaii volcano-type flow? Wrong magma type I suppose.

    “Yellowstone is due to erupt at any moment.” I was told by a geology/paleontology graduate student that “soon” is a very long time as far as Yellowstone volcano is concerned. Do I need to move out of Illinois now and to where? How are you predicting the eruption?

    As I understand it, Yellowstone is a “Super” volcano, meaning one like Vesuvius that killed Pompeii and Herculaneum, only bigger.
    “Gases in the Magma suddenly come out of solution in a most violent way.” As in a gigaton to million megaton explosion that puts 100 cubic miles of stuff into the stratosphere? No place on Earth is safe?

    RC: Yellowstone volcano could be an interesting post since it could “reset” the climate by ending the USA.

    Comment by Edward Greisch — 18 Apr 2011 @ 1:35 AM

  37. The petition is at:

    Comment by Edward Greisch — 18 Apr 2011 @ 2:14 AM

  38. OT… but I’d love to see a post on Xu et al 2011 and the current state of the Amazon.

    Comment by Sphaerica (Bob) — 18 Apr 2011 @ 12:46 PM

  39. Fugitive methane from fracking could just as easily be higher than Howarth estimated. We have no idea, since there is little monitoring or measurement.

    It’s not just fossil fuels. EIA data relies on industry submittals- for the steel industry, for example, there are gross estimates for mining emissions, but EIA lacks the personnel or inclination to check the numbers. This is even more true for the timber industry, which has a long history of falsifying or ignoring data on all kinds of subjects, but especially inventory and emissions. For example, the public has no idea that North American forest mortality has doubled since 1970.

    Homebuilders and LEED are probably the worst. They basically rely on industry claims for emissions and toxins, which- surprise!- results in the same specifications they had before, things like toxic plywood, vinyl window frames, and the whole rot of it. Our houses last a fraction as long as those in Europe.

    If someone wants to really investigate something like fracking, they are going to have to hire a qualified group that will investigate all of the variables in detail. Hard science is just the beginning: statistical training, LCA methodology, and doggedness are also required. I recommend IERE from Seattle.

    Comment by Mike Roddy — 18 Apr 2011 @ 5:11 PM

  40. As stated in the post “In deciding whether one activity is ‘better’ or ‘worse’ than an alternative, people need to have an assessment of the cost, the carbon footprint, other impacts etc., over that whole life cycle”
    One of the aspects not treated in the Howarth analysis is the “full life cycle” emmisions of the coal and oil they compare it too. All coal has methane adsorbed onto the organic material at a molecular level. (Shales have similar properties which is why there is such a vast reserve potential of shale gas.) Roughly 20 to 50 times as much gas can be adsorbed as can be held in the interstitial porosity. During any coal mining, either sub-surface mines or open pit mining the adsorbed methane is going to be released. (one of the reasons the old saying about canary in a coal mine saying came to be is methane released during mining creating dangerous levels of other gases reducing breathable air and creating flammable situations) As common values for the adsorbed gas in coals range from 50 to 500 scf/ton (standard cubic feet per ton) there are trillions of cubic feet of methane sorbed onto coals worldwide. Which is why CBM (Coal Bed Methane) gas production is economically viable. However, NONE of the methane released from any coal minig is even thought about or considered as a fugitive emission, therefore is not considered in the comparison. With regards to oil production huge volumes of gas are dissolved in oil. When the oil is produced the lowering of pressure as the oil comes to surface releases this gas as what is termed “solution gas”. In many countries with out export potential for this gas or in offshore production without gas gathering and distribution systems a lot of solution gas is vented or flared. Again another instance of ignoring fugitive emissions. So comparing shale gas and its fugitive emissions directly to combusting coal or oil significantly skews any analysis by willfully ignoring the “whole life cycle” of the various hydrocarbon systems and therefore overall is a completely invalid proposition.

    Comment by Phyllograptus — 18 Apr 2011 @ 6:24 PM

  41. Mike Roddy@39. I agree with the general premise you expressed, but wonder where you get your info on LEED. For instance, for LEED NC 2009 for New Construction, there are no fewer than eleven credits dealing with indoor air quality. There are other materials credits as well.

    As a result, LEED-based product specifications are indeed quite different from business as usual. Moreover, I can tell you from experience that specifiers working on LEED projects are on the lookout for greenwashing.

    I do agree with your larger point as I understand it. When it comes to CO2 abatement, there are massive potential savings in building siting and design, embodied carbon in building products, and — for commercial buildings — a transportation component ripe for savings.

    Looking beyond LEED, I recommend further research into Passivhaus, the Living Building Challenge, and the 2030 Challenge.

    Comment by Walter Pearce — 18 Apr 2011 @ 7:27 PM

  42. According to Howarth they included the fugitive emissions from coal (the volatiles released in the mining. Be that as it may, it is hard to imagine that this would be larger from fracking the gas out of the rocks as the heating value of the volatiles in coal is a large fraction of the heating value of the coal. OTOH, loss of gas from pipelines is in the less than 10% but more than 1 or 2% category depending on where. This can be controlled, but it does cost. Eli gets the feeling that Howarth threw the kitchen sink at the gas, and the smaller bathroom one at coal.

    Comment by Eli Rabett — 18 Apr 2011 @ 11:18 PM

  43. @Les Johnson, #19

    Thanks for the shout-out. As the quote from our blog states, us we’re quite skeptical about Prof. Howarth’s analysis. I tried to document why on the blog post to which you linked.

    But you did not mention another point that we prominently made in our blog post, as have many others: Our current knowledge of emissions from venting and leaks from US natural gas is unacceptably poor (both from fracking and from conventional gas wells). EPA’s estimates were increased – retroactively to 1990 – by huge amounts in the past few months. Their estimate for 2008 went up 120%!! That’s 5.5 Tg of “new” methane that just appeared in the inventories.

    We clearly need more accurate, credible measurements and inventories for the methane emissions from fracking, from other types of gas wells (most of the increase I mentioned above was from conventional wells, not fracking), and from other fossil fuels, which are also big sources of CH4. Other fossil fuels certainly shouldn’t escape some scrutiny!

    Meanwhile, as so many have noted, the natural gas industry is fighting efforts to get better data in the inventories by fighting the EPA’s reporting rules for greenhouse gases.

    We need good information about where the leaks are, and we need to get these leaks cleaned up as soon as possible.

    Comment by David McCabe — 18 Apr 2011 @ 11:50 PM

  44. @Gail, #34
    Methane is indeed an important precursor of ozone in the troposphere, which is an important greenhouse gas. However, this is taken into account in the calculation of global warming potential for methane – it includes the warming caused by ozone created during oxidation of methane, and also warming caused by water in the stratosphere resulting from methane oxidation up there.

    @Phyllograptus, #40
    Prof Howarth did include methane emissions from extraction of coal (and from petroleum).

    Comment by David McCabe — 18 Apr 2011 @ 11:58 PM

  45. This is OT, but Mike Roddy’s statement @ 39 that “North American forest mortality has doubled since 1970” might benefit from some examination.

    I assume Mike is again referring to: van Mantgem et al. 2009. Widespread increase of tree mortality rates in the western United States. Science 323:521. (

    I think this is an important paper, but just reading the title, one might observe that the study is about the western US, not “North America” and that it refers to increasing rates of tree mortality, not forest mortality. Reading the article reveals that the study was restricted to stands greater than 200 years old.

    Interpolating from the article’s Supporting Online Material (, forest stands that in 1970 had about 460 trees/ha were down to 430 trees/ha by 2007.

    A 6.5% decrease in average density, of stands over 200 years in age, is an finding worth reporting, but is it the same as a doubling of “forest mortality?”

    Comment by Rick Brown — 19 Apr 2011 @ 12:37 AM

  46. OT: NYTimes has just put out an editorial on the upcoming Supremes decision which is still at this moment open for comments. Denier central is very busy there and it could use some help:

    Comment by Susan Anderson — 19 Apr 2011 @ 6:53 AM

  47. With any luck, the court will rightfully decide with the defendants.

    Comment by Dan H. — 19 Apr 2011 @ 10:16 AM

  48. OT, responding to #45–

    Me, I think Mike Roddy was probably correct. True, the study Rick cited was about western trees, but then the West accounts for the majority of North American forest, if I’m not mistaken. And while “tree mortality” may not be identical to “forest mortality,” I think it’s at least reasonable to assume that they are strongly related! (And the former may well have been what Mike R. intended.)

    Let’s look at some papers.


    From the abstract:

    The current outbreak in British Columbia, Canada, is an order of magnitude larger in area and severity than all previous recorded outbreaks4. Here we estimate that the cumulative impact of the beetle outbreak in the affected region during 2000–2020 will be 270 megatonnes (Mt) carbon (or 36 g carbon m-2 yr-1 on average over 374,000 km2 of forest). This impact converted the forest from a small net carbon sink to a large net carbon source both during and immediately after the outbreak. In the worst year, the impacts resulting from the beetle outbreak in British Columbia were equivalent to 75% of the average annual direct forest fire emissions from all of Canada during 1959–1999. The resulting reduction in net primary production was of similar magnitude to increases observed during the 1980s and 1990s as a result of global change5.

    This is of course a still smaller subset of data, based as it is upon numbers from British Columbia. But since the current outbreak is “an order of magnitude larger in area and severity,” and since we know that the bark beetle problem extends through most of the Rockies, from BC down to Colorado, we have a good indication that the problem is really extraordinary.


    This tells us that 15 million ash trees in “urban and forested settings” have been killed since 2002 by the Emerald Ash Borer. Many more are at risk, and containment efforts are ongoing.

    3) Of course, that’s pest mortality, which, while it has a strong anthropogenic component, may not be what Rick was thinking about. So, let’s compare two studies addressing tree mortality:
    (A study of fire-suppressed old-growth forest in California, showing overall stem mortality at 8.7%)
    (A study of a Mexican mixed forest with no fire suppression, showing “cumulative mortality rates of 2.7-3.6%.)

    Now, I can’t tell for sure if this is apples-to-apples or not. But it appears to suggest that perhaps fire suppression is increasing tree mortality, at least for old-growth mixed forest.


    Here’s a study looking at drought mortality in the Southwestern US in response of the drought of 2002-2003. 90%. This one’s definitely food for thought.

    All studies so far come from the first page of a Google Scholar search. (“forest mortality north america,” 2005-2011.)

    Searching “tree mortality” instead–this seems to be the normal terminology–brings up this:


    From the abstract:

    Here we present the first global assessment of recent tree mortality attributed to drought and heat stress. Although episodic mortality occurs in the absence of climate change, studies compiled here suggest that at least some of the world’s forested ecosystems already may be responding to climate change and raise concern that forests may become increasingly vulnerable to higher background tree mortality rates and die-off in response to future warming and drought, even in environments that are not normally considered water-limited. This further suggests risks to ecosystem services, including the loss of sequestered forest carbon and associated atmospheric feedbacks. Our review also identifies key information gaps and scientific uncertainties that currently hinder our ability to predict tree mortality in response to climate change and emphasizes the need for a globally coordinated observation system. Overall, our review reveals the potential for amplified tree mortality due to drought and heat in forests worldwide.

    OK, that one definitely goes beyond the American west.

    6) Returning to North America, and the search for “tree mortality” papers, it does seem that the Northeast, or at least parts of it, has been less affected so far–so one study from the search (not linked here) affirms. Yet the future appears to be less secure.

    . . . ongoing increases in growing season. . . will most likely evapotranspiration and frequency of drought [increasing] the risk of fire. . . Climate and hydrologic changes could have profound effects on forest structure, composition, and ecological functioning. . .

    This sentence from the abstract emphasizes the projective aspect of the paper, but the overall study looks at a lot of recent historical data from the Northeast. I haven’t looked at it in detail yet, but it appears quite substantial.

    OK, this is a long comment already–especially for one that’s OT!–so I’ll stop.

    But clearly it’s not hard to find more support for Mike’s statement than just van Mantgem 2009. After all, this comment is the result of about half an hour’s searching by a rank amateur. And I’d love to hear what Mike Roddy has to say about the sources underlying his original comment. I bet there’s a lot more to be said.

    Comment by Kevin McKinney — 19 Apr 2011 @ 10:18 AM

  49. Dan H.,
    Oh, I’ve no doubt the court will side against the environment. The question is what we are doing by having the Supreme Court rule on a matter of physical reality.

    Comment by Ray Ladbury — 19 Apr 2011 @ 11:20 AM

  50. Kevin McKinney @ 48: I’ll respond briefly over on the Unforced Variations thread, which is where this belongs.

    Comment by Rick Brown — 19 Apr 2011 @ 11:50 AM

  51. #49–

    Don’t be too sure, Ray. The courts may not be up on the science per se, or even on ‘reality’ generally, but they do have good expertise in assessing the credibility and logical consistency of witnesses.

    So hope that Steve Goddard, Anthony Waqtts, or perhaps the good Baron himself, files an amicus brief. With friends like that. . .

    Comment by Kevin McKinney — 19 Apr 2011 @ 11:58 AM

  52. Ray Ladbury: “The question is what we are doing by having the Supreme Court rule on a matter of physical reality”

    As I understand it, the question before the Supreme Court has nothing to do with the physical reality of AGW. It has to do with whether pending EPA regulation of GHGs preempts the ability of states to sue GHG polluters under the federal common law of nuisance thereby using the judicial system to compel emission reductions. It’s a legal and political question, not a scientific question.

    EPA has already decided the scientific question with its endangerment finding, and is moving to regulate GHGs accordingly (as the Supreme Court already ruled the EPA must do if it determined that GHGs endanger public health). This case does not challenge that finding.

    Comment by SecularAnimist — 19 Apr 2011 @ 12:55 PM

  53. Ray,
    [edit--OT, purely political]

    Comment by Dan H. — 19 Apr 2011 @ 1:35 PM

  54. 49, Ray Ladbury: The question is what we are doing by having the Supreme Court rule on a matter of physical reality.


    The Supreme Court adjudicates cases based on the relevant laws. The EPA case is about which laws apply, which laws have supremacy over other laws, whether EPA followed the determinative laws, and therefore who wins the case.

    [Response: Veering rapidly off topic, end of discussion on politics please. Thanks.--Jim]

    Comment by Septic Matthew — 19 Apr 2011 @ 1:44 PM

  55. While noting that the current Supreme Court case is off-topic, I would just like to say that I am very surprised that some commenters here don’t seem to understand what the case is even about.

    It has nothing to do with science, and it has nothing to do with whether the EPA followed “the law”.

    It simply addresses the question of whether the EPA’s stated intention to regulate GHG emissions from electric power plants, in the absence of any actual EPA regulation to date, preempts a lawsuit by several states that sought judicially-imposed limits on such emissions.

    [Response: Thanks for clarifying. Good place to end the discussion.--Jim]

    Comment by SecularAnimist — 19 Apr 2011 @ 2:24 PM

  56. Sorry OT but, a link to a draft of:

    Earth’s Energy Imbalance and Implications (James Hansen, Makiko Sato, Pushker Kharecha) has been published at Climate Etc.

    I haven’t read it all yet, but what from what I have seen it looks damn good, and more or less what I have been waiting for expectantly. So Congrats! I will have some quibbles I am sure but hopefully nothing to cry about.

    Anyway Nice One Jim (et al.)


    Comment by Alexander Harvey — 19 Apr 2011 @ 6:39 PM

  57. There is no proven and documented instance of hydraulic fracturing of a well causing ground water contamination.

    Comment by Don Miller — 19 Apr 2011 @ 8:02 PM

  58. There is no proven and documented instance of opening a soda bottle causing soda to go flat.

    “There is no proven and documented instance of hydraulic fracturing of a well causing ground water contamination.” – 57

    Comment by Vendicar Decarian — 19 Apr 2011 @ 8:31 PM

  59. 57: Although I doubt your statement, the issue is water contamination from fracking, but rather whether the watsewater was properly disposed of. The real pollution comes from the few operators who violate the law.

    Comment by Thomas — 19 Apr 2011 @ 9:23 PM

  60. Gavin: We can tease the human signal out of CO2 emissions, and it is increasing atmospheric CO2 content by only about 0.6% per annum.

    Using Howarth’s numbers of around 3% leakage, gives about 54 Tg of methane per year leaking. The Tropospheric methane sinks, according to the IPCC, is 490 for OH, 30 for soil and 40 for stratospheric. Other sources list Cl at 25 Tg. The total is about 585 Tg per year in sinks.

    Howarth’s supposed leaks would amount to nearly 10% of all sinks.

    And we would not see this signal?

    Again, methane levels were flat, when gas production increased 25% over a time frame of a decade. Global gas production over the last few years is flat and even down, but methane levels are up.

    There is no linkage to natural gas production and methane levels, especially with the leakage rates proposed by Howarth. We would NOT lose that 10% signal, regardless of natural variability or or other anthro emissions.

    Comment by Les Johnson — 20 Apr 2011 @ 6:17 AM

  61. 55, SA: It has nothing to do with science, and it has nothing to do with whether the EPA followed “the law”.

    Yeh, sorry. I confused it with a different case.

    Comment by Septic Matthew — 20 Apr 2011 @ 12:26 PM

  62. Edward Greisch: Your

    28 Les Johnson: Just wondering: Does a valve leak more when it is partly closed than it does when it is fully open? I’m thinking a partly closed valve would have more internal pressure than a fully open valve.

    An open valve leaks more. More pressure inside a partially closed valve means more potential energy. Less pressure in an open valve means that potential has been liberated.

    What is “flowback”?

    In the case of fracturing (and some other operations), the well is flowed back after the treatment, to remove water and solids from the casing and wellbore area. Both interfere with hydrocarbon production, so they need to be removed. If the well was treated with nitrified fluid, the enrgy comes from the N2. Otherwise, tubing is lowered into the hole, and a gas, usually N2, is pumped down the tubing, and up the casing.

    Well casing gas: What is it and how does it flow through solid concrete? Or could somebody explain this stuff please?

    A well casing leak is a leak through or by the steel casing cemented in the ground to protect surface waters. The cement may be solid, but there may be mud channels that the cement bypassed when it was placed. Gas may also form channels in the cement as the cement transitions from a liquid to a solid. Or the cement may have been damaged after it set.

    The cement is not really solid, just as the rock the hydrocarbon comes from is not solid. Most producing formations have porosity of 5% to 40%. The higher the porosity, the more likely the porosity is interconnected, allowing flow through the rock. Its the same with cement, though it is usually an order of magnitude lower permeability (or more)than a producing zone. Gas though, can flow, albeit very slowly, in the some of the more permeable cements.

    Fortunately, this is a point source leak, and relatively easy to fix. It is also mandated by most jurisdictions. In Alberta, for instance, a single 30 ml bubble in 10 minutes, is enough to force the company to repair the leak. Companies are also finding that its much cheaper to NOT have the leak, than to repair it.

    Comment by Les Johnson — 20 Apr 2011 @ 12:29 PM

  63. Lots of fracking controversy here in CO recently

    Comment by Al — 20 Apr 2011 @ 4:42 PM

  64. Industry project to improve accuracy of methane emission factors:

    There are a number of infrared methods for detecting fugitive methane, including some which supposedly can be done from a plane flying overhead. Perhaps use of such methods by industry was responsible for finding and fixing many methane leaks, and thus for the plateau of methane concentrations, until the recent increase in fracking.

    Comment by AIC — 21 Apr 2011 @ 4:50 PM

  65. Les Johnson @22: I think your math is wrong. You’re comparing cubic meters of natural gas — which are accounted at one or more fixed temperatures and pressures (often 0 degrees C and 101 kPa) — with cubic meters of the atmosphere, whose temperatures and pressures vary widely.

    You’ve got to convert the mass of the leaked CH4 and the mass of the atmosphere into volumes at the same temperature and pressure, then compute the leaked CH4′s volume fraction. When I did this, I got ~10.9 ppbv, which — given the various margins of error — hardly falsifies Howarth’s paper.

    Comment by Meow — 22 Apr 2011 @ 2:29 PM

  66. Meow: I am using 1 standard m3 of natural gas. It weighs about 0.6 kg per standard m3. If 1 standard m3 of gas leaks into the atmosphere, there will still only be 1 standard m3 of gas, regardless of air temperature or pressure.

    If the globe produces 3000 billion m3 per year, that would mean that 54 billion kg of methane is released, at 3% leakage. (3000*.03*.6)

    54 billion kg is equal to 54 Tg. The volume of methane sinks and sources, and total atmospheric content, is given in the same unit; Tg. If the total leakage is equal to 10% of the total sinks, we will see the signal. Again, anthro CO2 is visible at only 0.6% addition. 10% should be highly visible.

    Nope, my math is right.

    But your number also falsifies Howarth. 10.9 ppb is greater than the observed rise the last few years.

    Comment by Les Johnson — 22 Apr 2011 @ 3:19 PM

  67. 1) Decarbonizing the energy supply is not what we need. Stabilizing the atmospheric concentration of greenhouse gases is what the goal should be.

    What’s the difference? Well, food is an energy source for human beings, correct? Should we decarbonize the food supply? Does eating food and, in the process, converting it to CO2, raise the atmospheric CO2 level?

    No, it does not, since the food was synthesized using atmospheric CO2 as the raw material (for production of sugars, fats, proteins, etc.) by green plants.

    Hence, if you make fuel from the atmosphere using similar strategies – solar powered synthetic chemistry combing carbon (from CO2) and hydrogen (from H2O) to make, say, CH4 (methane) or longer-chain hydrocarbons, then you can burn that fuel without altering the atmospheric level of CO2.

    Put another way, one could say that the % 14C content of all hydrocarbon fuels should be identical to the % 14C content of the atmospheric CO2 pool. (Fossil fuels have been in the ground for millions of years, hence all 14C has decayed away).

    2) There is plenty of evidence that groundwater supplies have been contaminated by the fracking process:

    If this isn’t the case, than surely the gas drilling industry will be willing to give up the exemptions from the Safe Drinking Water Act and the Clean Water Act, granted by Congress in the 2005 Energy Policy Act? Who needs exemptions if there’s nothing to fear?

    3) Funny, isn’t it, that no-one has suggested building ‘zero-emission’ natural gas plants that capture and sequester all CO2, prior to pumping it back into the very same shale formations it came out of, isn’t it? Methane has more energy per C atom than coal, so it should be significantly less costly to due this.

    The reason this hasn’t been suggested is that CCS is still technologically implausible, energy costs being far too high. They can’t even build a natural gas CCS prototype for public display, much less a coal CCS system – anymore than they can build a car that drives down the street while capturing all its emissions. Nevertheless, die-hards are still plugging the notion.

    4) As far as panaceas, large-scale solar and wind plants coupled to energy storage/distribution systems are entirely capable of meeting electricity needs without resorting to fossil fuels or nuclear. Sooner or later, that’s how global electricity will be supplied, and everyone will wonder why it took so long to do. It will not be a cheap panacea, but then, fossil fuels and enriched uranium are not cheap either, and are far more expensive in the long run.

    Comment by Ike Solem — 22 Apr 2011 @ 3:26 PM

  68. Les Johnson @66: It’s OK to compare mass fractions, but recognize that atmospheric concentrations are pretty much always expressed as volume fractions (e.g., ppbv), not mass fractions. Since methane’s molecular weight is ~16 g/mol and air’s is ~29 g/mol, this matters. That said, I made an error, and do now get ~21 ppbv, so this point is moot.

    On the broader question of what signal should be visible in atmospheric CH4 levels, that has much to do with the uncertainty in our measurements of the sources and sinks, as well as actual variations in sources and sinks. I don’t know those uncertainties and variations offhand. Does anyone else here know?

    Finally, you’re comparing apples and oranges when you say, “If the total [CH4] leakage is equal to 10% of the total sinks, we will see the signal. Again, anthro CO2 is visible at only 0.6% addition.” The effective annual anthro CO2 contribution is ~2 ppm (= ~0.5%) of atmospheric CO2 *content*, not ~0.5% of CO2 *sinks*. Since atmospheric methane concentrations are about 1775 ppbv (AR4 WG1 s.2.3.2), the hypothesized CH4 leakage is about 21 ppbv/1775 ppbv = 1.2% of content, not 10%. Should that be detectable over the time fracking has been widely used? I’d have to know much more about how the sources and sinks work to say. With CO2, we have a reasonably good handle on how much we add, both by accounting how much of which fossil fuels / forests we burn, and by studying changes in CO2 isotope composition (Plant-derived CO2 has a different C isotope composition than most atmospheric CO2). .

    Comment by Meow — 22 Apr 2011 @ 4:52 PM

  69. meow: your

    (Plant-derived CO2 has a different C isotope composition than most atmospheric CO2)

    Yes, the exact same difference can be found in CH4. Biogenic CH4 generally has C14. Fossil methane does not.

    Again, anthro CO2 can be recognized at the 0.6% increase each year. If this in the 7 Gt range, that means that the signature can be detected, even though this is less than 1% of natural sinks or sources (using IPCC sources). For methane, we are talking about 10% of the natural sinks or sources, at the leakage postulated by Howarth.

    As for the CH4 sources and sinks? The IPCC seems pretty confident with the numbers I posted earlier.

    Comment by Les Johnson — 23 Apr 2011 @ 12:15 PM

  70. meow: and you completely muddled this up:

    (Plant-derived CO2 has a different C isotope composition than most atmospheric CO2)

    Plant derived CO2? While plants do respire CO2, they are a net CONSUMER of CO2. I assume you mean the oxidization of plant matter. I hope you mean that, anyway.

    [Response: Instead of rushing to disagree with everyone anyone else says, please note that there has been a net source of plant-derived CO2 into the atmosphere from deforestation - roughly 2 GtC per year. -gavin]

    Your main argument in this statement is totally backwards, though.

    Most atmospheric CO2 is similar to CO2 from plant decomposition, because that is where MOST of the CO2 in the atmosphere comes from. Plants take in CO2 from the atmosphere, then CO2 from the plant decomposition goes back into the atmosphere. As N14 is converted to C14 on a continuous basis in the atmosphere, the supply of C14 for plants is relatively constant. Only when the carbon is sequestered, and the C14 decays, does a measurable difference show up. ie; fossil fuels.

    But, the vast majority of atmospheric CO2 is biogenic, so has C14. Fossil fuel CO2, without C14, and added at a 0.6% ratio per annum, is detectable.

    [Response: Actually, you are confusing your isotopes. 14C does discriminate between 'new' carbon and fossil carbon - but this is not easily detectable in the present day atmosphere because of the 14C contamination due to atmospheric bomb tests in the 1960s. Instead, 13C is the isotope that is most used since biogenic CO2 has less 13C than background carbon (i.e. oceanic C). Fossil fuel is biogenic, so is depleted in 13C, and this has lead to a decrease in atmospheric 13C over the last century. Finally, your analogy to CH4 sources is kind of moot - If there was only one anthropogenic source then it might be ok, but there isn't. There are large interannual variations in many of the natural sources - wetlands, Arctic lakes etc., and uncertain and varying trends in many human sources - irrigation, animals with entertic fermentation, fugitive emissions from conventional sources, landfills etc. - each of which has varied isotopic composition. My point is not that the Howarth estimates are correct - there simply isn't the monitoring in place to say - but that back of the envelope calculations are not as straightforward as one would like. - gavin]

    I would think that 10% addition of CH4, as suggested by Howarth, would also be detectable.

    Comment by Les Johnson — 25 Apr 2011 @ 3:21 AM

  71. Les states that “Fossil fuel CO2, without C14, and added at a 0.6% ratio per annum, is detectable”, and therefore that “I would think that 10% addition of CH4, as suggested by Howarth, would also be detectable.”

    First, I suggest that there are some subtle differences between the metrics in these two statements. The 0.6% is not directly comparable to the 10%. Also, “detecting” the signature of fossil fuel CO2 by looking at the atmospheric record is a different challenge from “detecting” the size of CH4 leaks from natural gas operations in the atmospheric record.

    Second, the key comparison should be between the expected theoretical change in atmospheric concentration due to the change in emissions, and the year-to-year variability in atmospheric changes due to poorly quantified sources (whether natural or anthropogenic). If unquantified variability is small, then moderate changes in emissions should be detectable, but that would not be true if the variability is large.

    Third, going back to CO2: yes, it is clear that the historical increase in CO2 is due to human activity. However, would we be able to “detect” a 10% change in, say, human CO2 emissions from deforestation by monitoring atmospheric concentrations? The answer for a single year is clearly “no”: the year-to-year variability in the “airbone fraction” leads to ranges between 30 and 80% (see Figure 7.4 in Chapter 7 of the IPCC AR4). Even the 5 year average varies from 40% to 60%. So, in order to “detect” a 10% change in human CO2 emissions would require that emission change to be sustained for probably at least 10 years…

    Since the AR4 states that “Past observations indicate large interannual variations in CH4 growth rates (Dlugokencky et al., 2001)”, we would not expect to be able to “detect” a 10% change in CH4 emissions any easier than a 10% change in CO2 emissions.

    Inverse modeling estimates can use atmospheric measurements to attempt to constrain CH4 emissions from different sources, but these modeling assessments are challenging and still leave a lot of uncertainty in the size of specific sources.


    Comment by M — 25 Apr 2011 @ 9:53 AM

  72. Gavin: your

    [Response: Instead of rushing to disagree with everyone anyone else says, please note that there has been a net source of plant-derived CO2 into the atmosphere from deforestation - roughly 2 GtC per year. -gavin]

    Yes, that’s what I said to meow. Decomposition of C to CO2.

    I doubt though, that there is net source of CO2 to atmosphere from plants. Several studies, including NASA, show a gain of vegetation, on the order of 6%, over the last few decades. There can’t be both a net gain and a net loss.


    Instead, 13C is the isotope that is most used since biogenic CO2 has less 13C than background carbon (i.e. oceanic C). Fossil fuel is biogenic, so is depleted in 13C, and this has lead to a decrease in atmospheric 13C over the last century.

    Granted. But pyrogenic methane will also drag down C13. Or more grasses growing vs C3 plants. Or a reduction in primary production.

    What is certain, is that if a 0.6% CO2 increase (vs sinks) can be observed, so can a 10% increase in CH4. You are looking for the same isotope (or lack of) in both.

    Comment by Les Johnson — 25 Apr 2011 @ 12:37 PM

  73. gavin: I think you are wrong on the C14. Fossil methane should be totally lacking in C14. An increase in C14 from atom testing (or pressurized water reactors)would only show the variance to a greater extent. “New” methane will show the increased C14, “old” methane won’t.

    Granted, methane from permafrost or methane hydrates would also have a low C14, but leakage from these sources are, as of yet, still minor.

    Comment by Les Johnson — 25 Apr 2011 @ 12:49 PM

  74. M: your

    we would not expect to be able to “detect” a 10% change in CH4 emissions any easier than a 10% change in CO2 emissions.

    That’s the point. They can detect a change of CO2 at 0.6%, which is attributed to anthropogenic causes.

    Comment by Les Johnson — 25 Apr 2011 @ 12:54 PM

  75. Les: 0.6% for CO2 is the change in atmospheric concentrations per year. 10% for CH4 is the quantity of CH4 from one source divided by the sinks. They are two different numbers. More importantly, you have compared neither number against the background variability from poorly quantified sources. Go look at Table 7.6 from the IPCC AR4, notice the huge differences between different inventories. It is not hard to imagine a “new” source of 10s of Tg, and a correction of several “old” sources to have less emissions. It is also not hard to imagine that while one source is increasing, another source might be decreasing.

    Comment by M — 25 Apr 2011 @ 4:27 PM

  76. M; The point is that Howarth says 54 Tg of CH4 is leaking from gas wells.

    54 Tg would overwhelm all sinks except hydroxyl.

    It is hard to imagine a new SINK with the same capacity to take 54 Tg.

    Its also hard to imagine that this would not be traceable, even if a new sink took the equivalent of all the leaking gas. Especially as the “old” gas will be C14 free, and the “new” gas will be steeped in it.

    Comment by Les Johnson — 26 Apr 2011 @ 8:29 AM

  77. I suggest that burning crude oil fuel should be stop if people can find another source of fuel
    that is recyclable.According to various researchers that the huge amount oil in middle east will be drained out on a specific time.Thus it should be conserve for the next generation.

    Comment by James griffin — 27 Apr 2011 @ 8:26 PM

  78. Can the isotopic composition of atmospheric CH4 be measured well enough to determine the source of the increase? e.g. 14C for fossil vs biological, 13C for cattle vs peat bogs, etc.

    Comment by Lab Lemming — 27 Apr 2011 @ 11:09 PM

  79. Walter Pearce, I’m a builder, and have worked with LEED for many years. You’re right that they do pay attention to IAQ, and LEED is not all bad. My point is that for comprehensive analysis of environmental impacts you might as well throw out LEED. Many of the professionals are well intentioned, but they lack scientific training (most are architects) and don’t understand data.

    Rick Brown, #45, I got my data from RPA (sorry I don’t have the link handy). US mortality was .8% in 1970, 1.7% in 2005 or so. The methodology is to survey sample plots all over the country every few years. There are thousands of them, so the numbers are good.

    This is very important information, especially for our climate. Climate blogs do not cover this issue well, since most are run by atmospheric guys.

    Comment by Mike Roddy — 28 Apr 2011 @ 8:41 AM

  80. “The Howarth study, using admittedly poor observations (for lack of anything better), has come up with a relatively large potential for fugitive emissions from the fracking process itself – up to a few percent of the extracted gas. Converting this into an equivalent CO2 amount (for comparison with the impact of the gas once it is combusted), they have used Global Warming Potentials (GWPs) from Shindell et al (2009) (a paper I co-authored)”

    This is a preposterous and absurd statement apparently issued with complete ignorance of the fracking process, and a total disregard for the scientific method advocated by any acceptable philosophy of science.

    First, the potential for any methane release during the “fracking” process is almost 0. There is a large hydrostatic head against the subsurface formation during pumping, and no potential for subsurface methane emerging to the surface occurs until well after the fracking procedure is ended and flowback of the frac fluids to the surface occurs. Had the authors taken the time to familiarize themselves with the basic mechanics of the process about which they write, they might have realized that their chosen vocabulary betrayed a complete incompetance and embarrasing ignorance of the subject matter they exposit.

    Only during flowback is there any potential for methane release, but since the operator of a methane well has every economic insentive to capture the methane for pipeline sales thus not allowing it to escape into the atmosphere, the conclusion that an operator would allow significant venting of gas into the air goes against all rationality. During the short times when the pipeline sales are disrupted, wellsites have a flare stack which combusts the methane minimizing release.

    It is clear that a complete abrigation of the scientific method has been committed in the first study, and that this represents no more than extreme environmental advocacy with no intent to arrive at any known objective reality. The authors of the second paper, in using junk data from an unscientific paper, have completely compromised all of their conclusions.

    The scientific value of these papers is worse than zero since almost assuredly erroneous conclusions are presented under the guise of “objective science”.

    [Response: Please calm down. Perhaps you can point us to credible estimates of the amount of fugitive emissions from the shale gas extraction process and processing? The fact that fugitive emissions are lost sales is not lost on anybody, but if you think that means that fugitive emissions must therefore be zero, you are very wrong - try looking at these operations with an infra-red camera. If your point is that we should get better numbers on these emissions - then we are in complete agreement. - gavin]

    Comment by Bryan S — 28 Apr 2011 @ 1:41 PM

  81. I hope someone more knowledgeable than I am will take a brief look at this. I’ve been enjoying my subscription to Earth Observatory reports, which just turned this up:
    “Earthquake Swarm near Hawthorne, Nevada”

    Since I’d heard there were some problems with earthquakes (I think it’s the deep injection wells, if I remember correctly, not the fracking) near shale gas operations, I took a look. Quick google on shale gas in Nevada turned up this (among others):

    Am I all about in my head?

    Comment by Susan Anderson — 28 Apr 2011 @ 2:48 PM

  82. Bryan – An expansion of your reasoning here: . . . the conclusion that an operator would allow significant venting of gas crude oil into the air Gulf of Mexico goes against all rationality. Not to mention against the law as well as against the common good. S#!t does happen, quite regularly in some industries.

    Comment by flxible — 28 Apr 2011 @ 2:50 PM

  83. Gavin,

    If you would like to learn something, then I would be quite happy to help provide you with some perspective on this process. If however your idea is to grandstand, then the conversation is over and you will go away not learning much for the trouble. It will ultimately be your loss and not mine.

    Another related issue: You tell a reader that fossil fuel is “biogenic methane”. Again, your vocabulary betrays a shallowness of knowledge on this issue. In organic geochemistry related to shale gas, one must differentiate between “biogenic methane” and thermogenic methane. Most methane related to “shale gas” in the deep subsurface is not “biogenic methane” in the sense you indicate, but rather “thermogenic” methane. This process is related to the “thermal cracking” of mostly algal-derived kerogen under heat in the deep subsurface. Thermogenic methane is certainly a “fossil fuel” but is most definitely *not* isotopically light relative to “biogenic methane”. So your statement above is a muddle that communicates nothing, or worse, mis-communicates some basics.
    “Biogenic methane” is a term that refers almost exclusively to bacterial methanogenesis (such as in a garbage dump or in shallow microbial laden freshwater aquifers), and is “isotopically light” in comparison to “thermogenic” methanogenesis.

    My point to your reader is not to embarrass you, but simply point out that not all opinions on the subject of shale gas and extraction are equal. There are many opinions, but only a few are likely uttered by folks who may be competent enough in the field to deserve a hearing. I’m afraid you do not appear to have yet put in the time and effort to have learned basic terminology in this emerging area of geology, and therefore disqualify yourself (in at least my eyes) as a knowledgeable public intellectual on this issue.

    Unfortunately in this discussion, the most qualified persons to render a competent judgment at this stage of the game are likely those research scientists who are employed by the petroleum industry and have spent several years now on the front lines of this research, yet whose opinions the general public will understandably likely not regard as “objective”.

    However, it would likewise be a mistake to necessarily consider “credible”, “definitive”, or “objective” the information coming from folks who may have scientific credentials, but who are clearly “novices” in these particular areas of research.

    My advice to you is to invest in some detailed and hard-won deep research into this subject before popping off.

    P.S. If you are truly interested in learning something about shale gas, I would be happy to send you my contact information and take this discussion off line.

    [Response: I am always willing to learn. You'll find that I have made no claim to deep knowledge about shale gas, and I'm happy to have pointers to, for instance, an isotopic study of this methane source. And if you could point to credible studies - even from the industry - of fugitive emissions, that would do everyone some good. But why you feel the need to jump in feet first with the insults is a little puzzling. Really, communication is much easier if you don't do that. I don't have any particular agenda here - indeed, I only wrote the piece to highlight the GWP issue where I do know what I'm talking about. If you want to increase the level of knowledge on this thread, please go ahead, but drop the attitude. - gavin]

    Comment by Bryan S — 28 Apr 2011 @ 5:08 PM

  84. Bryan: Why is “biogenic methane” isotopically light compared to “thermogenic methane”? Do algae (from which you say that the thermogenic methane is derived) have a different 13C selectivity than bacteria (the source of much of the biogenic methane)? Or do you selectively lose 12C during the thermal cracking process?

    (Also, in defense of Gavin’s vocabulary, I have seen “biogenic” used in the sense of “biogenic” vs. “fossil” for methane as you defend, but also in the sense of “biogenic” vs. “abiogenic” for fossil fuel formation. Google the term “biogenic theory of petroleum” or the like, with the key being that fossil fuels were ultimately formed by biological rather than geological processes. Therefore, for CO2 studies, “biogenic” vs. “abiogenic” is a useful differentiation between all CO2 sources ultimately derived from plants – both fossil and biomass burning – versus CO2 resulting from changes in ocean solubility or volcanic degassing) (and yes, it is important to know how a term is used in a specific field: eg, the confusing of engineers when confronted with climate scientist’s use of the word “feedback”: but I’d argue that in this case the use of the word is set by the context, and Gavin was fairly clear that he was using biogenic in the 2nd sense)

    Comment by M — 29 Apr 2011 @ 8:45 AM

  85. @ Susan Anderson — 28 Apr 2011 @ 2:48 PM re “Earthquake Swarm near Hawthorne, Nevada”

    The Chainman Shale formation doesn’t appear to extend as far west as the earthquake swarm near Hawthorne NV. I think that it’s more likely that the swarm has to do with basin and range block faulting transition to Eastern Sierra uplift and the volcanism associated with the Long Valley – Mono Lake – Aurora-Bodie areas.
    see discussion of Aurora-Bodie volcanic field & Mud Springs Volcano

    Comment by Brian Dodge — 29 Apr 2011 @ 10:42 PM

  86. What if mining crude oil was the reason for the Earths mantle (and oceans) heating up? What does oil do for machinery? How many gallons of crude oil spilled out into the gulf in the latest Oil platfrom mishap? How many oil platfroms/wells are there in the world?…How long have they been operating? Makes you wonder doesn’t it?…Now, who wants to tell the oil tycoons to stop mining crude oil?

    Comment by richard copeland — 30 Apr 2011 @ 1:42 PM

  87. Brian Dodge, thanks. That was exactly what I was looking for, someone who really knows what they’re talking about.

    I do worry about all the manipulations we are performing, as mentioned by Richard in 86 (or if renumbered, at 1:42 pm), but tend to think this kind of imagining goes too far. However, we are fiddling with stuff that is more out of our control than we are willing to admit, as witness the BP oil spill. I don’t think that tale is told yet, but take heart from the undoubted fact the cascade of consequences is always more complex and interesting that our worst fears and best hopes.

    Comment by Susan Anderson — 30 Apr 2011 @ 9:29 PM

  88. richard copeland – is the mantle warming up?

    Comment by arch — 2 May 2011 @ 8:14 PM

  89. Richare Copeland:

    Whiskey. Tango. Foxtrot. Interrogative.

    Comment by Ray Ladbury — 3 May 2011 @ 8:05 AM

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