It’s all about me (thane)!

This was incorporated into figure 2.21 in AR4, where it is clear that the impact of methane (once some indirect effects are included) is greater than you would have thought based on the ‘abundance’ viewpoint. Note the changes basically only affect the reactive species. When thinking about the various metrics, the emissions-based view is more closely tied to GWP than the traditional abundance-based approach. A big difference is that GWP is looking forward in time, while emission-based forcings are looking back at historical events.

The increasing sophistication when it comes to attribution and GWP is strongly connected to the development of more comprehensive Earth System Models (ESM) in recent years. These are the descendants of the General Circulation Models of the climate that have been developed over the last 30 years, but that now include interactive atmospheric chemistry, aerosols (natural and anthropogenic) and sometimes full carbon cycles in the ocean and land surface. This extra machinery allows for new kinds of experiments to be done. Traditionally, in a GCM, one would impose atmospheric composition forcings by changing the concentrations of the species in the atmosphere e.g. the CO2 level could be increased, you could add more sulphate, or adjust the ozone in the stratosphere etc. However, with an ESM you can directly input the emissions (of all of the relevant precursors) and then see what ozone levels or aerosol concentrations you end up with. This allows you to ask more policy-relevant questions regarding the net effects of a particular sector’s emissions or the impact of a specific policy on climate forcing and air pollution (see here for a discussion).

Our new Science paper (Shindell et al, 2009) expands on some of the earlier work (as was discussed here) and extended consideration of the indirect effects of CH4 and CO (carbon monoxide) to aerosols as well. This is necessary since SO2 requires oxidants to transform to sulphates (and so is affected by the perturbation of the chemistry by other emissions), and it takes into account the competition between nitrates and sulphates for ammonia (which means that there is a small anti-phasing effect – increasing sulphates tends to decrease nitrates and vice versa). When we did this, we found that methane’s impacts increased even further since increasing methane lowers OH and so slows the formation of sulphate aerosol and, since sulphates are cooling, having less of them is an additional warming effect. This leads to an increase in the historical attribution to methane (by a small amount), but actually makes a much bigger difference to the GWP of methane (which increases to about 33 – though with large error bars).

Currently methane levels are relatively stable (despite small upticks in the last two years) and are running below IPCC projections made in 2001 (this of course is good news). However, CH4 is at more than twice its pre-industrial concentration and so still presents a tempting target for emission reductions which, because of our new work and the relatively short lifetime in the atmosphere, will likely be a little more effective at reducing future forcings than previously thought. Given the value of methane as a fuel, it is likely that more of it will be captured (as in this recent story).

CO2, however, is still increasing dramatically despite the slow down in the economy, and so current growth in radiative forcings is dominated by CO2 and that will very likely continue for decades. Despite our increasing appreciation of the role of other forcings (including land use for instance), the overwhelming driver of climate change in the 21st Century will be CO2 increases.

In a follow-up post, I’ll discuss the sources of methane and the implications of the new results for attribution of climate forcing to different sectors (including agriculture), where there have been some very odd (i.e. wrong) recently published numbers.

Page 2 of 2 | Previous page

191 comments on this post.
  1. Mark J. Fiore:

    I am an amateur climate guy who reads a LOT about global warming.I went to Harvard, 1982, and Boston College Law School, 1987, and live in San Francisco.RealClimate is nice enough to let me post my opinions, which I do, a few times a year.
    So, here goes.First, this is another EXCELLENT post by Gavin.Some of my comments in the past on this site have focused on the real danger of the vast amounts of methal hydrates at the bottom of the ocean melting.The above post by Gavin shows that there are some extra warming considerations to worry about regarding methane.
    I recently attended the Dominican College booksigning event for Al Gore here in Marin County, CA, and he said something in his speech that I had only learned last year, namely, that the net carbon content of soils worldwide is four times that of all vegetation on the planet.He also said there is some connection between using all those nitrate fertilizers on the soil and the ability of the soil to bind CO2 in the future.Also, the production of meat worldwide leads to increases in methane.I know that methane excreted from the billions of livestock on the planet is a huge problem.
    It is late, and I’m now entirely unsure of where this post is going, so let’s say I’m still deeply worried that, somehow, if methane starts increasing significantly(which Gavin said ,above,the numbers, thankfully, do not show,)that there will A WHOLE LOT of other unforeseen negative feedbacks from methane, in addition to the ones posted above, which have not really made it into the mainstream press reports about methane.
    I did read that methane was bubbling up from somewhere in the Arctic, and we do know that methane is double its preindustrial levels…
    Thanks for further educating me, Gavin, and I hope for the best regarding the planet and methane emissions.However, there still seems to me to be an “aura” about methane emissions that to me is deeply unsettling.
    Mark J. Fiore

  2. Geoff Russell:

    When you do your follow up paper, perhaps you can comment also on Stacy Jackson’s
    recent Science (Oct 23) Policy Forum paper. She presented a figure showing
    that of our forcings, the things we do, as opposed to the things our ancestors
    did, methane forcing is similar to co2 forcing. A similar chart
    appeared in AR4 (chapter 2, p.206).

  3. PeterPan:

    According to this paper, OH has been increasing until 1989, with a minimum in 1998 (that they blame on wildifres and an intense El Niño) and a recovery since then (2003 comparable to 1979):
    It would be interesting if you could give some context with observations (including aerosol forcing, if possible) in the upcoming post.
    (later, they also mention methane, but the variations seem small and temporary.


  4. Tim Joslin:

    Very clear on methane, even to this amateur.

    I would like to ask a question on one incidental point, though. I notice that Fig 2.21 includes a (negative) surface albedo forcing from land use changes, but that Fig 2.20 does not.

    But land use changes (such as from tropical forest to arable land and later semi-desert) don’t just imply an albedo change. They also imply changes in surface moisture. Surely the moisture change has an effect on climate comparable in magnitude to the albedo change?

    The point, of course, is that evaporation of water at the surface absorbs heat, limiting the increase in temperature caused by the incoming solar radiation. This reduces the heat radiated away compared to dry land of the same albedo. Instead, much of the (“latent”) heat is released at altitude when the water vapour condenses, perhaps to form clouds. I’d be very interested to know the overall forcing effect arising from this process, but it clearly has the arguably desirable consequence of moderating surface temperatures and raising temperatures higher in the atmosphere: compare the surface temperatures in deserts and forests at similar low latitudes. The presence of moisture in the forest ecosystem clearly outweighs the albedo effect on temperatures at the surface, at least during the day.

    Isn’t it a little arbitrary to just consider the albedo forcing component of land use change?

  5. Inferno-fan:

    Stop voting for RealClimate, vote for real Blog Science, vote for DenailDepot (Best Science Blog 2009:

  6. Stephen:

    Hi Gavin,

    when you say that CO2 is increasing “dramatically”, what is the current state of play between (i) emissions and (ii) atmospheric concentration since it is (ii) that impacts climate, whilst (i) is unimportant, except to the extent that it causes changes in (ii)? My impression is that whilst emissions of CO2 have broadly increased on a “business as usual” basis, atmospheric concentration has increased somewhat less than expected. Is this so? If so, “dramatic” does not seem like a good description for a smaller than expected increase in the thing that matters.

    Thank you for any clarification.

    Kind regards,


    [Response: CO2 emissions are rising faster than expected, while concentrations are rising about as fast as expected. But this is dramatic. Increases of ~ 2ppmv/yr is 200 times faster than the rate of rise coming out of the last ice age. – gavin]

  7. Michael Maier:

    Al Gore is a politican, i`m right?

    Why is he writing climate books?

    [Response: Because dealing with climate change is a political issue? – gavin]

  8. Mike Roddy:

    I’m surprised there was no mention of Katey Walter’s work in Siberia and Alaska. Potential methane releases from permafrost and arctic lakes appear to be a major hazard. Walter’s results are quite scary, and I look forward to your take. There is obviously a lot of guesswork when it comes to the relationship between increased global temperatures and rates of arctic methane release, but I assume that you have looked into this as well.

  9. jhm:

    This reminds me of a item I read about agricultural fumigation: “CAMBRIDGE, Massachusetts, March 11, 2009 (ENS) – Sulfuryl fluoride, a gas used for insect control, has the potential to contribute to future global warming at more than 4,800 times the potency of the better known greenhouse gas carbon dioxide, an international team of researchers said today.”

    I wonder if the combined effects of such non CO2 (and CH4, I guess) GHGasses are even close to CO2. In other words, is CO2 so dominant that even a collection of agents “4,800” times as effective (more accurately, there absence) can really make a dent?

    [Response: The net effect is the GWP multiplied by the number of kg emitted. Therefore chemicals that are around in concentrations in the parts per trillion are ~10^8 times less effective than CO2 if they have the same GWP, and still 10^3 times less effective with GWPs of 10,000 say. The key trace gases that make a notable difference are the CFCs, HFCs, HCFCs etc. See the figure on this FAQ for some scale. – gavin]

  10. Stephen:

    Thanks for you in-line comment above Gavin. It is fantastic that there is a forum where one can pose a question and get an almost real-time response from leading climate scientists. I take the point about the increase in CO2 relative to emergence from the last ice age.

    On my monitor, the lines for the emissions scenarios in the chart that you link to all appear as red, so they are unfortunately indistinguishable. So I read the relevant bits of AR4 and also the Special Report on Emissions Scenarios. Have I got this right?: Scenario A1B looks most like how the world has been recently, but actual CO2 emissions are somewhat higher than this, which implies that economic development scenarios may be to modest in the amount of CO2 they generate. Whilst on the other hand, CO2 concentration has risen at a slower rate than would have been expected if there had been an accurate emissions scenario, which implies that the scenarios are too pessimistic in terms of how they translate emissions into increases in concentration (missing sinks etc)?

    Kind regards once again,


    [Response: They are pretty much indistinguishable because the differences are small. The scenarios don’t tend to diverge noticeably from each other until 2030 or so. Note too that there is more uncertainty in the emission data (particularly related to deforestation) than there is in concentration data. – gavin]

  11. tharanga:

    Will the upcoming post also discuss methane sinks, and try to clarify why the methane concentration in the atmosphere has stabilised, for now?
    The IPCC FAR has some discussion, but I assume there’s since been some progress on understanding that.

  12. Christopher Hogan:

    I’d like to ditto #8 above. I think the last posts here dedicated to arctic methane were from December 2005 (Methane Hydrates and Global Warming)and April 2006 (Kristof on the Apocalypse, basically a short followup to the first).

    I believe the conclusion at that time was that disaster (very rapid warming due to release of arctic methane so rapid that it built up in the atmosphere) was unlikely, and that the arctic was more likely to play a role in providing a chronic addition to GHG releases. There was a passing mention in an October 2006 post (Rasslin’ swamp gas) with the same conclusion: no plausible way to see significant methane release from ocean clathrates this century.

    Basically, whenever arctic methane has come up, the posts here have argued against the likelihood of catastrophic events. Which I deeply appreciate.

    Conversely, I looked at some videos recommended on this site (Climate Denial Crock of the Week), and came a cross a clip of Energy Secretary Chu discussing arctic warming, where he suggested that 4 – 6 degrees centigrade increase in (presumably) global temperatures would be that point at which there was high risk of unstoppable positive feedback from temperature to arctic emissions to temperature. I think he says something like arctic emissions would dwarf anthropogenic emissions. Chu’s interview is about 6:30 in on this:

    Not sure what Chu’s source is for that. And that’s all emissions not release of methane from clathrates.

    When I juxtapose Chu’s 4 to 6 degrees with the recent MIT research suggesting 5 degrees centigrade rise by the end of the century is plausible (due largely, I think, to above-trend increases in emissions), find that troubling.

    It would be nice to hear from the experts whether any information since 2005 would change the tenor or conclusion of the December 2005 post. Basically, what I’m asking is, if we actually hit the median MIT prediction, is the arctic and arctic methane more of an issue, and if so, how much more? Is Chu’s statement correct in essence?

  13. anna:

    Hi Gavin,

    I’ve been interested in methane for a while now but something I’ve been struggling to find out is what the global warming potential of methane is, in CO2-e, over it’s *actual* lifetime in the atmosphere (which I understand to be 12 years +/- 3).

    The IPCC report gives the GWP for methane over 100 years (25) and 20 years (72), but not over it’s actual lifetime in the atmosphere. The closest I’ve found is that the GWP over a decade is ‘about 100’, which is a little vague.

    If this is something you could shed some light on I’d greatly appreciate it, I understand you’re very busy.


  14. anna:

    Oh, and a quick response to Inferno-fan @ #5:

    Thanks for the suggestion, but sorry, you’ve totally failed to convince me that I should vote for that blog as you haven’t presented any evidence, merely an assertion.

    If you want to convince people, you really do need to present thorough, accurate evidence to them in a clear manner.

  15. Steve Missal:

    You all might be interested in reading the following link:

    (Author)Dan Dorritie….

    A paleontological take on the problem that is worth a gander.

  16. Jonathan Mulligan:

    I’ve read that the water storage dams of the world could be significant contributers to methane, when the vegetation rots underwater. Is the three gorges dam in China of sufficient size to account for the recent increase, after nearly a decade of static methane levels?

    I do worry that agriculture is an easy target without due regard for it’s importance by people well removed from the realities of having to feed over 6 billion mouths . I’d rather do without electricity than starve.

  17. James Staples:

    What about me(flat screen TV’s manufacturing process releasing Nitrogen Tetrafluoride)?
    According to the GRIDA PDF that I just downloaded, it has not been assigned an ‘official’ GWP by the IPCC; but it’s estimated to have one of between 100-8000!!!
    One of my local Representatives (Earl Blumenaur – a True Friend in DC, for people like us) came into a meeting saying, It’s O.K. – it’s O.K.! The economy is healing – everyones buying New Flat Screen TV’s!!! It’ll all be OK now!”
    What a Joker!

  18. Andy Stahl:

    Gavin, et al.,

    Congress adopted the following provisions as part of the 2010 Interior Appropriations Bill, which President Obama signed into law on Oct. 30:

    Sec. 424. Notwithstanding any other provision of law, none of the funds made available in this Act or any other Act may be used to promulgate or implement any regulation requiring the issuance of permits under title V of the Clean Air Act (42 U.S.C. 7661 et seq.) for carbon dioxide, nitrous oxide, water vapor, or methane emissions resulting from biological processes associated with livestock production.

    Sec. 425. Notwithstanding any other provision of law, none of the funds made available in this or any other Act may be used to implement any provision in a rule, if that provision requires mandatory reporting of greenhouse gas emissions from manure management systems.

    It appears that the livestock industry and its political allies have not gotten the methane message.

    My questions are 1) “Did climate activists and/or scientists know about these provisions? 2) If “yes,” what did they do to stop their adoption, or if “no,” why not?

  19. philc:

    Methane oe CO2, I’m having a hard time interpreting what I read about global warming or climate change.
    I found this graph on logicalscience of Dr. Hansen’s original climate predictions updated with instrumental readings.( The graphs of various scenarios seem to still fall in line with the newer climate models. However, only ScenarioC falls in line with the actual temperature data. Scenario C is based on effective limitation of the major GHG’s including CO2, methane, soot, etc. The other scenarios seem to follow the predictions of later global models.

    Then there is this graph from NOAA( The observed data seems to be a pretty good match with Hansen’s for 1960-1995. But the observed data since `1995 seems to be a better match for Scenario C, which assumes large reductions in the rate of GHG emissions. What gives?

    Then we have this graph( which is the UAH satellite data which seems to be a pretty good match for the NOAA global temp data graph.

    The problem I have is that all the current climate model predictions I can find do not predict the leveling off, and possible start of a cooling trend, beginning around 2001. Looking at the historical data, the current peak could easily be similar to 1940 or 1960. The only way to tell is to wait and see, since the models all predict the temperature to continue rising from 2001 on.

    So, why believe a model prediction?

    [Response: Physics. – gavin]

  20. Marcus:

    This is an Excel spreadsheet equation for the “Bern Carbon Cycle Approximation” for CO2, where B18 is the number of years you want to calculate:

    This is the same calculation for CH4 (with a much simpler lifetime expression!):

    Multiply the output of the CH4 cell by the CH4 forcing (3.7 * 10 to the -4), and divide it by the output of the CO2 cell times the CO2 forcing (1.4 * 10 to the -5). Multiply by 44/16 (to correct for the different masses of the gases) and multiply by 1.4 (for the ozone and stratospheric H2O corrections). If you use 100 years you get 25.5, and for 20 you get 72, matching the IPCC. For 12 years, you’d get about 88.

    Having said that, I’m not convinced that there is much meaning in calculating a GWP for the “lifetime” of the gas: we usually care about GWP in terms of timscales of impacts on the earth that we care about. 20 years is an approximation to caring about near term impacts, 100 is mid-term, and 500 is long-term.

    (to be even pickier, the CH4 lifetime of 12 years is not the “residence lifetime”, which is shorter, but rather the “perturbation lifetime”, which takes into account the fact that emissions of methane reduce the amount of methane sink available)

  21. Marcus:

    Anna: ps. On the off-chance that your response to Inferno was serious, you should know that “denialdepot” is a parody site. I note that your response to Inferno went exactly counter to the dogma of that site: denialdepot would claim that blog science works best by assertion, not evidence, and that thorough, accurate evidence presented in a clear manner is anathema to real blog science because it is just toeing the line of those scientific ivory-tower elites.

  22. Ike Solem:

    The short term effect on radiative forcing will depend on the rate of emissions due to feedback processes (permafrost melting leading to emissions) as well as deforestation and fossil fuel combustion

    For example, consider the last glacial termination, Monnin 2001:

    Or, see Figure 6.4 in the IPCC FAR chapter 6 – they don’t seem to have anything but the complete pdf file:

    During the YD period, centered around 12500 BP, there was a decrease in methane and an increase in CO2, at slow rates relative to today’s changes. One interpretation is that the oceans kept releasing CO2 as they warmed, but for some reason terrestrial methane production decreased – colder land temperatures could have done that. At the end of the Younger Dryas, the CH4 began to rise again, peaking around 10000 BP, which was within the Holocene thermal maximum.

    If you look at Figure 6.4(c), however, you can see that the Younger Dryas termination was just a blip in the radiative forcing, one that is dwarfed by the changes today.

    It’s also intriguing that there is a gentle rise in CO2 and CH4 prior to the industrial era, 5000 BP onwards, probably due to human land use changes – everything from rice cultivation to clearing forests to raising livestock.

    You can see that non-fossil fuel sources have some effect just by looking at India today, where dung and wood fires contribute as much as half of the black carbon aerosol pollution. This has lead some to argue that if India increases rural electrification by expanding coal combustion, it will actually help reduce warming because there will be less black carbon emissions – a very curious argument, given that India is looking to import some of the dirtiest fuel on the planet, from Australia:

    Coral reef scientist slams Brumby over ‘reckless vandalism’, Nov 9 2009

    One of the world’s leading coral reef scientists has slammed the Brumby Government’s proposal to export Victoria’s brown coal to India as “reckless vandalism”.

    John “Charlie” Veron, who discovered a quarter of the world’s identified coral species, said any move to export the state’s vast reserves of brown coal would only further endanger the Great Barrier Reef.

    “It’s reckless vandalism. Brown coal would have to be the dirtiest, nastiest form of energy there is. It is absolutely essential that it remains in the ground. That is obvious,” he told The Age.

    Unless coal-fired power plants in India will capture and bury all the emissions from that brown coal, how could building modern coal plants lead to a net reduction in forcing? How does switching to coal reduce methane emissions, and how plausible is it that Indian coal power plants will be built with European-style clean air controls, when those controls have barely made it to the U.S., thanks to industry resistance?

    Furthermore, how does replacing biomass (sourced from atmospheric CO2) with coal (sourced from geologically stable carbon reservoirs) help reduce future warming? There is really no justification for India or China to subsidize the expansion of coal-fired power, but of course the same goes for U.S tar sand pipeline subsidies, coal-to-gasoline subsidies, depletion allowance subsidies and the like.

    India is even running a PR program to support coal expansion, with the latest claim being that the glaciers aren’t really melting:

    Clearly the best solution for rural electrification program in India is solar power – the area is right in the sun belt, and instead of trading with Australia for coal, they could trade for solar panels, which also increases domestic energy security, which allows the local economic systems (farms & factories) to function – as well as the coral reef ecology.

  23. Lynn Vincentnathan:

    I have a question. CH4 breaks down into CO2 and what else. Don’t answer if takes too much time.

    [Response: Mostly water. – gavin]

  24. Lynn Vincentnathan:

    I remember David Archer’s earlier RC post “Methane Hydrates and Global Warming” at

    One of the points was the rapidity of the warming and melting of hydrates (and permafrost). Methane only lasts about 10 years in the atmosphere, but if enough of it is released within a 10 year frame due to the rapidity of the warming (other disasterous warming events of the past happening over much longer periods), this could spell real disaster, something not experienced in the world’s history.

    And just as with ice sheet and glacial disintegration being caused also by mechanical processes (beyond the warming), there are those undersea Storegga slide events that could also release vast quantities of methane.

    (I hope I got this somewhat right. Actually I hope I’m dead wrong.)

  25. rustneversleeps:

    This is a little off-topic, but maybe “on-topic” insofar as methane emissions, sources and concentrations…

    Nate Lewis at Caltech has some interesting slides, articles and talks up on his site. w.r.t. transitioning to low-carbon power, etc.

    One thing that has surprised me more than once in listening to the talks is that he seems to suggest that we can distinguish “permafrost” methane in the atmosphere based on measuring the Helium isotopes. (???) It seems to be analogous to the changing 12C/13C ratios for atmospheric CO2.

    Here is an exact quote from an article in the MRS Bulletin, Oct. 2007:
    An example of these effects is the melting of the permafrost, which we know is happening because we can isotopically date the helium being released. This He has not been released from the permafrost in at least 40,000 years.

    I have never seen or heard of this before. Some googling shows nada… Certainly it would be rather useful to be able to distinguish this.

    I posed this once before at Tamino’s and someone answered – as I recall – that the scarcity of He to begin with makes this seem unlikely. Seems reasonable…

    Anyhoo. I should probably just be asking Nate Lewis about this, but does anyone here have any insight about what he is referring to? If it’s true, I think that is something important. If not, what’s he on about???

  26. Hank Roberts:

    For Andy Stahl, try these for starters:



    The latter is a start toward knowing the “legislative history” for that provision; your library can help you assemble that–much will be pointers to the Congressional Record.

  27. Hank Roberts:

    Oops, I always forget double quotes break in WordPress, so the searches above aren’t clickable; copy those strings and paste them into your web browser’s search box.

  28. Eli Rabett:

    Decreasing HO (Eli’s local model bunny friend says IUPAC don’t do OH, the more metallic element has to go first) is gonna have LOTS of greenhouse effects. For one big thing the degradation of terpenes and other complex aromatics given off by those killer trees is gonna go down, and since large organics are pretty much black bodies when it comes to IR, the greenhouse effect will go way up.

  29. CM:

    > It’s all about me (thane)!

    That would be the Thane of Cawdor, who pithily summarized our knowledge of historical radiative forcings as well as the hydrological impact of climate change: “…all our yesterdays have lighted fools the way to dusty death.”


  30. Marcus:

    Eli: An even bigger effect is the O3 resulting from the methane emissions not only has the radiative forcing effect included in this paper, but also attacks those same killer trees thereby reducing carbon uptake… yay for positive feedbacks!

  31. SecularAnimist:

    Gavin wrote: “In a follow-up post, I’ll discuss the sources of methane and the implications of the new results for attribution of climate forcing to different sectors (including agriculture), where there have been some very odd (i.e. wrong) recently published numbers.”

    Would “recently published numbers” by any chance be referring to the analysis by Robert Goodland and Jeff Anhang, recently published by WorldWatch Institute (PDF), which found that “livestock and their byproducts actually account for at least 32.6 billion tons of carbon dioxide per year, or 51 percent of annual worldwide GHG emissions”?

    [Response: Yep. ;) – gavin]

  32. SecularAnimist:

    Gavin, may I suggest that you send your upcoming follow-up post as a letter to the editor of WorldWatch magazine, as a comment on the Goodland and Anhang article re: GHG emissions from livestock production? WorldWatch does very often publish longish, substantive, detailed letters from experts in various fields who critique the articles they publish.

    Obviously there is a pretty wide disparity between the 2006 UN report which attributed 18 percent of GHG emissions to animal agriculture (which would already make it comparable to the transport sector which gets much more attention), and the Goodland and Anhang figure of 51 percent. It would be really great if you could help to clarify this question.

    It is worth noting that the various cap-and-trade proposals before Congress generally exempt “farmers” from cap-and-trade, where “farmer” is a euphemism for “gigantic corporate-owned factory farm confined animal feeding operation”. On the policy side, a question worth asking is why this one particular industrial sector should be excluded from cap-and-trade when it seems to be, by even the lower UN assessment, a major producer of GHG emissions.

  33. Hank Roberts:

    > why this … sector should be excluded

    Here’s why there’s a law against doing anything about it–the lobbyists headed the EPA off from doing something:

    In response to the FY2008 Consolidated Appropriations Act (H.R. 2764; Public Law 110–161), EPA has issued the Final Mandatory Reporting of Greenhouse Gases Rule. The rule requires reporting of greenhouse gas (GHG) emissions from large sources and suppliers in the United States, and is intended to collect accurate and timely emissions data to inform future policy decisions.

    Under the rule, suppliers of fossil fuels or industrial greenhouse gases, manufacturers of vehicles and engines, and facilities that emit 25,000 metric tons or more per year of GHG emissions are required to submit annual reports to EPA. The gases covered by the proposed rule are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFC), perfluorocarbons (PFC), sulfur hexafluoride (SF6), and other fluorinated gases including nitrogen trifluoride (NF3) and hydrofluorinated ethers (HFE).

    The final rule was signed by the Administrator on September 22, 2009. On October 30, 2009, the final rule was published in the Federal Register ( under Docket ID No. EPA-HQ-OAR-2008-0508-2278. The rule will be effective December 29, 2009. This action includes final reporting requirements for 31 of the 42 emission sources listed in the proposal. At this time, EPA is not finalizing the remaining source categories as we further consider comments and options.”


    Folks, if you care about policy, you need to be participating in policy. The science was solid on this a very long time ago; the EPA had gone through the political process as they routinely do.

    This isn’t something you can argue about at RC to any effect.

    Talk to your Representative and Senators about it, and to your state government.

    An example (just an example, you can find newer and better information) from California:

  34. Tenney Naumer:

    re: #14

    Anna, Denial Depot even had one of the RC group fall for it — hehehe

  35. Corey Watts:

    Thanks Gavin. Love your work.

    Surely the fact that atmospheric methane is so short-lived makes it an ideal target for emissions reductions? That is, we could make quite a difference in a short period of time, couldn’t we?

    [Response: Yes. That is exactly the point. – gavin]

    Also, can you comment on the reasons for the recent stabilisation and the more recent upswing? My understanding is that the former is something of an anomaly in the longer term trend. I read that it’s due to a mix of factors such as drought (causing emissions from wetlands to fall), increased temperatures (speeding up the destruction of atmospheric methane), reduced forest fires, a reduction in farm and fugitive emissions following economic decline in former communist countries, and higher rates of breakdown possibly due to higher temperatures.

    Have I got this right? What am I missing?

    [Response: It’s not clear unfortunately, and so future predictions of methane growth or stasis are still very uncertain. – gavin]

  36. Eli Rabett:

    Marcus, the IR spectrum of the terpenes and a lot of other biological effluvia are considerably wider than ozone.

    Even for such molecules as the HFCs, the delay in degradation might be important, although Eli assumes their chemistry is included in the model that Gavin is talking about.

  37. Greg Robie:

    I would value critique on the following observation concerning the methane “uptick.” When Revkin posted the BP example for capturing methane at gas wells at dotearth 10/22/09 about a gas field going from 4 billion cuft/yr to 10 million cuft/yr. I realized policies aimed at controlling methane may have been far more successful than the tabling of methane would indicate. That decade long tabling, which the ‘uptick’ relates to, is generally assumed to be do to plugging leaks in gas lines; changes in rice cultivation, and capping landfills. It relates to a measurement of the average level of methane in the atmosphere.

    The BP example may be extreme, but some of the plugs in the former Soviet Union gas lines may have been as dramatic as well. A cursory look at off set projects engaged in under Kyoto suggest a lot of them are landfill capping projects. Given that in Siberia methane was 5 times above background levels in 2003 and in the summer of 2008, up to 100 times greater over areas of the continental shelf in the Arctic, it occurs to me that the mitigation efforts may have masked an ongoing exponential increase in the release of methane in the Arctic.

    The distribution of methane in the atmospheres is strongly weighted to the northern latitudes. In the winter it seems to migrate north, being carried into the Arctic by the same atmospheric that gets other pollutants from the temperate latitudes up to the Arctic. With methane having about a 10 year life span (and Lynn #24, I have read that methane first become ethane on its way to becoming CO2 and water), such also suggests that the mitigating policies for CH4 have been more successful than appreciated.

    There is a dearth of scientists studying methane. I hear it reported from Copenhagen this past March that there are only 20 world-wide. Clearly, what funding there is has been focused on CO2. To the degree careers follow the money, such may explain both the lack of scientists and funding. The focus on CO2 would also explain why the renewed increase in CH4 might be labeled only an uptick.

    As I consider the changes in climate occurring in the Arctic, a factor I can see in play among all the others—and feeding all the others—is the overlooked ongoing methane increase. Are there any huge oversights in this analysis? If not, could it be further critiqued so we don’t continue to miss it?

  38. Antonio San:

    Gavin will surely point out how the GWP of CO2 was “calculated” by IPCC and point out the discussions at Shepperton in July 1992… or is that debate over too?

    [Response: the GWP of CO2 is one by definition. -gavin]

  39. Steve051:


    I wonder if anyone could give me some quick advice — I’m looking for some kind of climate simulator on the internet that could show, on a global map, what would happen if temps rose 8 degrees C by 2100, both in terms of sea level rise and topographic / temperature changes (desertification, arctic / antarctic melting, etc).

    I tried, but they don’t have a global simulator yet, and I don’t see anything about sea level changes.

    Pardon me if my terms are off, I’m a bit of an amateur at these things, but I hope the query makes sense. Help would be appreciated.

  40. catman306:

    Record number of record temperatures during the past ten years. (To help prove a point.)

    Reported in subscription only Geophysical Research Letters and at the
    NY Times and NPR.

  41. Gus:

    Kangaroos are the answer. Their gut microbes do not produce methane!! Get rid of cattle. Range Kangaroos.

  42. Marcus:

    Steve051: You can download the MAGICC model off the internet, it is pretty good for showing temperatures and precip globally for whatever emissions scenario you want, based on the patterns from a number of big GCMs.

    Desertification and arctic melt are harder problems – i don’t think that even good research models do those well yet. Antarctic melt might be included as a parameterization component for sea level rise, but you’d have to check the documentation. Thermal expansion and non-Arctic glacial contributions should be handled well, though.

  43. Andy Stahl:

    Hank, et al.,

    Thanks for the pointers. Professionally, I’m an environmental advocate (national forest policy), but not engaged in climate policy. My earlier post implicitly asked “If a couple hundred livestock operations can’t be stopped from legislatively exempting themselves from climate-related regulation, how the Hell does anyone expect to remake the world’s energy policies?”

    You can read the livestock industry’s success story here:

    I know this is primarily a “science” blog, but suspect there are lots of climate policy readers/advocates, too. Did you all decide to give the livestock industry a free pass this year? Or did you engage the livestock industry and simply lose in Congress?

  44. Hank Roberts:

    Andy, are you really asking why you only found out about this after the fact?
    Do you think someone should have known sooner than you did and stopped it?

    There’s a lot of history to this. It’s like the “death tax” and “death panel” stories — use of a made-up term and a gross distortion of the facts to pretend they’re against one thing (“cow burps”) and preventing something nobody’s proposed (a “cow tax”) and then rush through an amendment that actually protects the real crap artists who were going to be dealt with — the feedlot shitpile methane sources, which are far more serious problems.

    Yeah, it was a bait-and-switch shell game. It worked. Again.

    “… House appropriators approved a $10.6 billion spending bill for U.S. EPA last night, tucking in several amendments aimed at insulating agricultural interests from the reach of federal climate regulations … [including] provisions to block EPA regulations requiring factory farms to report their greenhouse gas emissions and exempt livestock operations from possible carbon regulations.”

    There’s a history, for example here:
    “THE INFLUENCE GAME: Excuse me! Lobby wins on burps
    June 20, 2009 By DINA CAPPIELLO , Associated Press Writer
    … On Thursday, Rep. Todd Tihart, R-Kan., successfully added an amendment to the spending bill that covers the EPA to block the agency from including biological processes of livestock – including the release of methane – as part of regulating greenhouse gases.

    That’s politics at work. The “you all” who gave the ag industry this free pass did it at the last minute. They claimed for years they were protecting farmers from a “cow tax” — but they exempted the huge manure waste problem.

    You could argue that this Congressman couldn’t tell the difference between a cow (a minor source not going to be regulated) from vast acres of pigshit (a significant source due to be regulated in December) — so he rushed in this amendment and protected both the cows and the pigshit, just to be safe.

    Or you could argue he got pwned, willingly, and has accidentally protected a big problem, using a non-problem as his excuse.

    If it’s the latter, the law can be refined next year (oops, midterm elections, got to win those first or lose the whole attempt to cope).

    Or you could get a much better answer from someone who really knows what happened — I put the above together from 5 minutes with Google and it’s just a sketch, a suggestion how to go about looking this stuff up.

  45. Andy Stahl:


    I found out about these pro-manure provisions on 9/18/09, after the House had passed the Interior bill, but before the Senate had acted. I track/lobby the Interior bill for forest-related matters and happened to see this crap. At that time, I notified a colleague who specializes in Clean Water Act lawsuits against CAFOs (confined animal feedlots). I paid no more attention to it since that’s not what I do.

    So, in answer to “Do you think someone should have known sooner than you did and stopped it?” Of course I do. What I’m trying to find out is “Does the climate activist community have its manure together?” This small example seems as good a test case as any.

  46. Anonymous Coward:

    Andy Stahl (#43) exlicitely implied (“how the hell …”) a very good question.

    But I don’t fell I’m part of his “you all”. The question I’m asking myself is quite different: what would be the point of focusing on relatively easy methane emissions reductions at this stage? Because, the way I see it, the most serious problem is the long-lived GHGs.
    I would understand the point of tackling pig shit and such once the hard problems are seriously addressed and are in the process of being fixed, in order to shave the peak off the forcing chart (so to speak). But I’m afraid that expending the few fast-acting tricks available so soon in the game would only strengthen the delayers’ hand by delaying painful climate change. I’m also afraid that short-sighted politicians might latch onto this methane business and leave the harder problems to the sucessors. And I’m afraid that people will wish they still had pig shitpiles to get rid of the day fast-acting tweaks are desperately needed.
    Are “you all” assuming that significant action on the root causes of the real, long-term problems in the next 10 or 15 years is a done deal anyway? I’m not such an optimist.

  47. Hank Roberts:

    Well, I certainly don’t speak for a “climate activist community” or even know who you’d mean.

    All the organizations I’ve checked so far on this problem had been addressing it over the long term. Up til the very last moment, with success — the EPA regulation was weeks away from taking effect.

    You may want to look at the history a bit differently, because this wasn’t only or perhaps even primarily a “climate activist” issue. The regulations are based on air quality problems, water pollution problems, disease problems — all the _other_ reasons for controlling agricultural industrial manure.

    This last minute amendment was packaged as a “cow burps” or “cow tax” item to sneak it by. Nobody was trying to regulate cow burps or tax cows. This is the “death panels” method of deception at work.

    The people who got nailed had worked on the public health aspects of this problem. Politics at work.

    You have to remember any bill can be amended to put in any unrelated language — this is how this crap gets done, by attaching language to important legislation at the last minute.

    If your point is that there are far more agribusiness lobbyists at work in Washington than ecologically minded citizens to watch them — so true. You can’t watch all of them all of the time. This stuff happens.

  48. Hank Roberts:

    PS for Andy, with a reminder I really don’t know much and this isn’t the place to find out — but I’d _bet_ this last minute language screws up a lot of business plans and that it will get revised as a result. If there’s no data collected on any greenhouse gases related to agriculture, or something as sweeping as that sounds, this kind of busines plan is dead before it starts I’d bet:

    How can you pay for, or do offsets against, something the law keeps people from reporting?

  49. Andy Stahl:


    EPA was trying to regulate livestock emission of greenhouse gases. In EPA’s own words: “A livestock facility that emits 25,000 metric tons CO2e or more per year from manure management systems must report.” The reporting rule would have regulated livestock facilities that “stabilize” or “store” manure, as distinct from spreading it on fields. Methane and nitrous oxide were also to be reported.

    This was 100% a climate activist issue. The title of EPA’s rule is “Mandatory Reporting of Greenhouse Gases.” The proposed rule has nothing to do with water pollution, disease problems, or other reasons for controlling industrial manure.

    The people “who got nailed” were the climate activist community. It does exist, e.g., NRDC, Greenpeace, 1Sky,, National Wildlife Federation, Sierra Club (a who’s who can be found at

    Unless we understand how and why significant anti-climate legislation made it so easily through Congress (was there any opposition at all?), we have little chance of passing meaningful climate legislation next year.

  50. philc:

    RE #19- Physics FAQ doesn’t really answer the question. Why do the current climate models show increasing temperatures over the 2001-2001 period when the observations show a leveling off, or even the start of a cooling trend?

    I would expect a valid model, or set of models, since it seems a bunch of different models do a better job than just one, would show 10 year trends.

    For validation, I would expect that you would make a series of runs over the same period and get some kind of running average of results that matches the observations to some degree. The better the model the closer it matches observation, and the finer detail it captures. The observation in the physics faq that over a long period the models are fairly insensitive to initial conditions means to me that, given initial conditions from 1850 say, the models should produce an output fairly close to observations after 100 years or so. I realize it won’t get down to forecasting temperatures at individual station or individual hurricane track, but it should track the trends in the data to some degree, particularly when short term trends change direction(barring volcanoes or meteor strikes). Since the models responded appropriately to Pinatubo, when it was factored in, why not the leveling off of temperatures?

    [Response: The results can be seen at this post showing what the IPCC models actually say. We will have an update on this shortly as well. – gavin]

  51. Hank Roberts:

    Andy, here’s the summary. Two amendments; one has a vote on record, the other was passed without taking the names (voice vote):

    Reporting of Greenhouse Gas Emissions for Greenhouse Gas Registry: This amendment added language to the bill prohibiting EPA from requiring livestock feedlots to report on their methane emissions as part of the reporting of greenhouse gas emissions for the Greenhouse Gas Registry. (This Latham (R-IA) amendment was adopted by a vote of 31-27.)

    Biological Sources of Greenhouse Gas Emissions: This amendment added language to the bill prohibiting EPA from promulgating a regulation to require Clean Air Act permits for emissions from biological processes associated with livestock production. (This Tiahrt (R-KS) amendment was adopted by a voice vote.)

  52. Hank Roberts:

    Comments and responses are interesting, for those who like this kind of thing:

  53. Steve Fish:

    My understanding of agriculture emissions of methane, and thereby CO2 in 10-12 years, is as follows–

    Some time ago there was a report that termites were a major source of methane. Their gut bacteria convert cellulose to sugars with methane as a byproduct. So to protect the climate some method for preventing termite farts should be developed.

    The deal is that the termites eat cellulose that was made by trees, or whatever, but this was created by plants that extracted CO2 from the atmosphere. So the methane release just replaced CO2 that had been extracted. A zero sum game.

    This is also true of cows, pigs, chickens, or whatever, but only as long as they ate vegetable products that grew naturally. That would be vegetable matter that cultivated or not, did not require any fossil carbon for its growth. The methane produced by a cow (or whatever critter) raised on corn that required fossil fuels for machinery, pesticides, and fertilizer for its production adds to the world CO2 load by the amount of these fuels required. This fossil carbon, and that for any other agricultural products produced for sale, is what the agriculture industry should be taxed for because it adds to the global CO2 load.

    Agricultural products can be produced without fossil fuels, but at a higher monetary cost to us consumers. This extra cost represents the, up till now, ignored “externality” of green revolution agriculture fossil carbon. If we all wish to contribute to preventing a major negative ecological, and resulting negative societal, shift we will have to pay more for our food. It is interesting that the poorest people of our world would not be affected at all by this change in production.

    Anybody, please explain where I am going wrong with this reasoning from an economic or physics point of view. Steve

  54. Anonymous Coward:

    Steve Fish (#53),

    It is not entierly true that only fossil fuels add to atmospheric CO2. If forests are cut down for the sake of agriculture or animal husbandry for instance, carbon that was tied down will be released into the atmosphere.

    In my mind there is a more serious misconception in what you wrote though: some of the poorest people would of course be very much be affected by an increase in the price of food in general and cereals in particular, which are globally traded commodities purchased by most of the world’s poor. This was vividly demonstrated in 2007-2008 and humanitarian organisations such as Oxfam had reports about the situation. Price is not a good way to think about such issues anyway. What matters is whether the amounts produced are adequate and I don’t understand how grain production could be sustained at anything like the currents levels without fossil fuels.
    Only a small fraction of fossil fuels are used in agriculture and that that is one of the most humanitarian uses for these fuels. There’s plenty of pointless, gross waste by the richest people of our world that could be addressed before cutting food production. But of course the rich wouldn’t be rich if they could be made to take on burdens instead of the poor.
    If you’re looking for measures that wouldn’t affect the poorest amongst us too much, curbs on grain-fed livestock and meat consumption in general would do the trick.

  55. Marcus:

    “Anybody, please explain where I am going wrong with this reasoning from an economic or physics point of view.”

    Your instincts are good: there is an important difference between fossil-derived methane and bio-methane, which is that when they oxidize to CO2 in the first case it adds to CO2 concentrations, and in the 2nd case it is CO2-neutral.

    What you’ve missed is that during the time that the methane was still methane, it has a radiative forcing that is 70 times that of CO2 per kilogram – and in addition, there are side effects from methane of increased ozone production, reduction in hydroxyl radical, etc. Having said that, we mostly don’t care about termite methane anyway – the general presumption is that natural sources that existed preindustrially get a pass (and would be very hard to control). On the other hand, massive rice paddies, giant herds of cattle, etc. are all larger in extent and number and methane emissions than the natural wetlands and bison herds and so on that they replaced. So between our voracious appetites for food on industrial scale, and fugitive methane emissions from landfills, coal mining, natural gas operations, etc., we have added enough methane emissions that methane concentrations are more than double their preindustrial levels (a little less than 1800 ppb today, about 715 ppb preindustrial).

  56. Steve051:

    Thanks, Marcus! Appreciated.

  57. MS:

    For a long time I have been wanting to ask about WF Ruddimans ideas in his book ”Plows, plagues and petroleum”. He brings out the idea that humankind has been affecting the methane cycle for a very long time (millennia).
    How broadly accepted is his idea?
    Should I count it as a wild idea, a good thought , a probable explanation or..??

  58. Steve Fish:

    Anonymous Coward (~#54. 14 November 2009 @ 7:51 AM), and
    Marcus (~#55, 14 November 2009 @ 8:44 AM):

    I agree with you both, except for some minor quibbles.

    Anonymous Coward (why not just use your name, I feel silly typing this), it is true that there is a pulse of carbon released by cutting a forest for agriculture, and for building your home for that matter (mine is made of recycled steel), but to accurately access the ultimate size of the pulse, you also have to subtract from this any carbon taken up by whatever is planted in its place. If sustainable agriculture were used, this could remove more carbon than the pulse, over time, by improving the soil. I am not sure if there is a difference in methane release from a mature forest and that from agriculture on the same land, perhaps Gavin will deal with this in the future.

    I should have qualified that the poor I was speaking to were those folks still engaged in subsistence agriculture. Unfortunately this group is shrinking because of the unsustainable, but inexpensive fossil fuel derived food that mega-agriculture is selling to them. They are also being entrapped into unsustainable (for them) agriculture by GMO crops. Such farmers, and farms, all over the world will have to be rehabilitated. I agree about the waste.

    I have two questions for you– What is the percentage of atmospheric carbon derived from fossil fuels used in agriculture? What is your plan for all the poor people when fossil fuels become so expensive that they won’t be able to afford the food (this may not be far off)?

    Marcus, I am aware of how methane works in the atmosphere. In the idealistic sustainable agriculture world, the amount of methane (from agriculture) would not be adding fossil carbon to the atmosphere and would be constant. We agree. We just have to deal with this. One way is to aggressively capture and use methane in order to minimize the atmospheric phase of this carbon. I would be interested in any ideas you have beyond removing a large percentage of humans from the earth.


  59. Rod B:

    Andy, Hank, et al: If they were to report emissions, how do feedlots and other livestock farming operations measure and then report their actual methane and CO2 emissions?

  60. Rod B:

    PS, never mind my question. Hank’s reference provided info sufficient for my interests.

  61. Peter Todd Williams:

    Thanks, Gavin.

    Before reading your post, I had the most recent Science smack dab in the middle of my desk, open to Shindell et al 2009. I thought it was an interesting read, but this is the first time for me that I’ve read an article *before* the spin came out.

    It’s a strange experience. I never would have imagined how the head-in-the-sand club could have twisted this the way they did. It shows how clever they are, which is the really alarming thing: the deniers aren’t stupid; they’re actually rather smart, and that’s why they’re so dangerous. They’re of that class of intelligent people who, rather than using their brains to discern the truth, instead use them to promote their own agenda/predetermined conclusions.


  62. Hank Roberts:

    MS, put “Ruddiman” in the (Site) Search box (top of the page)– much here.

  63. David B. Benson:

    MS (57) — Being but an amateur here, I’m not in a position to say how generally accepted Ruddiman’s ideas are. He has his critics and ably answers (most of) their objections; see his highly readable papers on his web site.

    His thesis includes not only methane (early rice production, for example) but also carbon dioxide levels. With regard to the latter, the increases during times of extensive land clearing for agriculture and decreases following great plagues is quite stricking. One such example is the decrease in CO2 concentrations following the spread of smallpox throughout the Americas; very good correlation with the regrowth of forests on both continents.

    IMO Ruddiman overstates the case for how cold it would be in, say, England without the human contribution to global warming (so-called greenhouse) gases. Certainly cooler with lower CO2 and CH4 levels, but not as cold as all that! Orbital forcing predictions show quite well that the next attempt at a stade (massive ice sheets) would not be due (baring anthropognic influences) for another 20,000-30,000 years.

    On the other hand, Ruddiman in a recent paper with a co-worker answers the objection of those wondering how so few people could have such a large influence on climate. The answer is simply less efficient agriculture than is now practiced; each farmer had a much larger impact then.

    All told, I think Ruddiman’s thesis holds up rather well. I regualrly recommend it as a popular beginner’s book about climate. Others do as well. One person stated he lent his copy to a lawyer; upon returning it the lawyer stated words to the effect of “At last! A book about climate I can understand.”

    I add that there are several more recent books about climate which might be better starters for those wishing to obtain some overview of climate. Nonetheless, the time prespective of by Ruddiman’s book is, I opine, uniquely important and so should continue to be recommended, right off the bat, to the curious.

  64. dhogaza:

    A bit OT, but Andy Stahl, thanks for all your hard work at FSEEE.

  65. Mike Smith:

    Sorry for being off-topic. I just noticed the apparent arctic sea-ice extent, reported by the NSIDC has dipped below the 2007 level.

    They also explain what could have caused the reduction in ice formation:

    Thanks for the awesome site: I’ve learnt so much!

    PS It’s a bit political, but you could mention what people could do to raise the issue of climate change with their elected representatives. Especially with COP15 ~22 days away.

  66. Hank Roberts:

    What dhogaza said, definitely many thanks to Andy Stahl; I hadn’t looked you up to see who you worked for. These are good folks, great website, with a lot of wonderful pointers for people.

  67. David Horton:

    #63 “The answer is simply less efficient agriculture than is now practiced; each farmer had a much larger impact then” David, this simply can’t be right. Look at the massively cleared areas in, say, America and Australia. the irrigation, the massive use of chemicals and fertilisers. Compare it to small scale farming with biodiversity retained in hedges and uncleared areas, organic fertilisers, few if any insecticides.

  68. Lawrence Coleman:

    What is the latest concensus re: what contributed to the extreme temps and loss of the arctic ice cover and a substantial loss of the antarctic sea and pack ice in the PETM 50M.y ago. If the level of CO2 in the atmosphere was only elevated by a third over normal levels..what caused the rest of the tipping points to be breached?. Are similar conditions present today?. Did an increasing CO2 suddenly force the uncontrolled interaction with other GH gasses?. Even though this process took roughly 10Ky to take effect. Nowadays the level of CO2 and CH4 is higher than what initiated the PETM, are crucial tipping points already being breached? Could it be that the increase in CO2 caused a sudden explosion of vegetation esp. in the tundra areas and as this vegetation died and began to rot down released massive amounts of CH4 to push a uncontrolled +ve feedback condition? Added to that how much CH4 hydrates were then 50M.y ago stored under the arctic tundra waiting to be released? Comments on this would be appreciated..thanks!

  69. Terran:

    Slightly OT, but why does the IPCC radiative climate forcings bar-chart include stratospheric water vapor but not tropospheric ?

    I remember the reason was something about water vapor’s short residence time in the atmosphere, I think, but never understood why that should exclude it from the list.

    [Response: It only refers to the component of water vapour change that is caused by human emissions. Nothing we do in the troposphere makes any difference given the large amount of water there already and the very short residence time (10 days or so). However, the stratosphere is very dry and has residence times measured in years. So the oxidation of CH4 (to produce CO2 and H2O) is a big deal (providing about half the water in the middle stratosphere for instance). Therefore an anthropogenic increase in CH4 leads to a direct increase in stratospheric H2O and that is what is counted. Changes in water vapour that occur as a result of temperature or circulation changes are still considered feedbacks. – gavin]

  70. Hank Roberts:

    Lawrence, did you read this yet?
    You asked about a study in an earlier topic but I never found a cite, can you point to that one?

  71. Hank Roberts:

    Oh, for Lawrence Coleman again, speaking of asking for cites,
    just above, you write: “Nowadays the level of CO2 and CH4 is higher than what initiated the PETM” — I’m curious where you got that idea. It does bear double checking against the information in the recent RC thread on the PETM.

  72. Thomas:

    Steve Fish @ 58
    I fear that industrial agriculture is unsustainable for more reasons than just fossil fuel inputs. It is also really tough on soil fertility, which is why fertilizer is such a large a part of it. We are mining phosphate deposits at a similar rate (wrt the amount available) as fossil fuels, and in my opinion they are more fundamental, as nonfossil fueled energy could be used to fix Nitrogen and drive tractors etc. Also we have been mining ground water at an even greater rate, and it is starting to run out in many places. Recent GRACE results estimated anual withdrawls of 54KM**3 for Northern India. These largely one shot agricultural inputs will soon collapse. The crunch may not be far off.

    Incidentally there was a Steve Fish in my New Jersey high school class of 70. Any chance that you are the same fellow?

  73. Terran:

    re: #69

    Gavin, I think you may be mistaken, the chart is of radiative forcings since 1750, man-made and natural.

    Its caption in chapter 2 of the AR4 WG1 report is:
    “Summary of the principal components of the radiative forcing of climate change. All these radiative forcings result from one or more factors that affect climate and are associated with human activities or natural processes as discussed in the text. The values represent the forcings in 2005 relative to the start of the industrial era (about 1750). [..]”

    Water vapor content hasn’t remained constant since 1750, and its net change is unlikely to have been zero, so it will have provided a radiative forcing.

    [Response: A forcing in this context is only for changes in composition externally imposed. Changes in water vapour that happen because of temperature changes affecting the saturation humidity are part of the response, not the forcing. Water vapour does have a radiative impact (which is why there is a feedback), but it isn’t directly affected by emissions. – gavin]

  74. Lawrence Coleman:

    Thanks Hank for the follow up..i’ll look into that, and the website as well.

  75. George Robinson:

    Here in Sweden we have on a national weather site, a carbon counter, which works for most of the time, and shows second by second the CO2 figures. It is not a true record but more of theoretical figures. Do you know if there is any such website where this is also done, somewhere in the world.


  76. Ray Ladbury:

    Coward asks: “…what would be the point of focusing on relatively easy methane emissions reductions at this stage?”

    Buying time so that we have time to tackle the really big problems. Every hybrid, every CF bulb, every light switch turned off or mile not driven makes a difference and buys time.

  77. June R:

    #75 George
    Try CO2 Now

  78. mike roddy:

    Thanks, Ike Solem, #22. I still await Gavin’s comment on Walter’s work.

    Gavin, you are right about the difficulty in measuring deforestation caused emissions, especially since the data is so politically explosive. I wrote an article in Forest Voice about North American deforestation, and its effect on our carbon budget. I proved that by switching from wood to steel framing, our emissions would be lowered more than if we required all new cars to be zero emission vehicles. Top forest carbon scientists helped with the research. The article and background research links are

  79. Steve Fish:

    Thomas (~#72, 14 November 2009 @ 11:59 PM):

    This is all very scary and pushed to the background, along with ocean acidification, by all the denialasphere hoopla. The crunch may be very ugly.

    My part of the Fish clan left Leicestershire for Rhode Island in 1643, moved west in several jumps, and arrived in California in 1925.

    mike roddy (~#78, 15 November 2009 @ 9:56 AM):

    Thanks for this information. A local, self advertised as green, architect told me that I was being unecological for building an all steel home. I knew he was wrong, but haven’t seen all the information put together like this.

    By the way, I couldn’t get your name link to work.


  80. Hank Roberts:

    Many of you probably know about this site; I just found out about it thanks to folks at

    “This resource has been developed by the Sustaining Family Forests Initiative (SFFI) using data from the National Woodland Owner Survey. SFFI is a collaborative of federal and state forestry and conservation agencies, businesses, and nonprofit organizations that realize private landowners play a crucial role in sustaining and nurturing our natural resources. It is coordinated by the Yale School of Forestry and Environmental Studies and the U.S. Forest Service’s Family Forest Research Center. “

  81. Chris Colose:

    Terran, you may be interested in this post on radiative forcing and feedback. Hopefully this will clear things up with water vapor

  82. john byatt:

    how would the all steel building stack up compared to the plantation timber
    house , in my own house i went for steel cladding on a plantation timber frame
    steel on steel tends to get a bit noisy

  83. JCH:

    Probably a silly question, but would manure from the 95 million cattle in the United States produce less methane if it the animals were widely dispersed in pastures instead of being concentrated in feedlots?

    [Response: Most of the methane from livestock is from their stomach’s fermentation processes, so that isn’t affected. But where you get a lot of effulent all concentrated together in anaerobic conditions, you will get more methane production there. I’m going to guess that this happens more on feedlots than on pasture. I don’t know how big of an effect that is. -gavin]

  84. Terran:

    #73: Thank you for the correction, Gavin.

    If I could ask another question about the radiative forcings charts : on page 32 of the Technical Summary (AR4 WG1), there’s a chart ‘Global Mean Radiative Forcings’. Adding up the RF values for the anthropogenic forcings gives 1.72 W/m2, yet the ‘total net anthropogenic’ figure provided in the chart is 1.6 W/m2. The difference between the two is 0.12 W/m2, which happens to be the solar irradiance forcing, the only non-anthropogenic forcing on the chart. How do these numbers fit together? Am I being dim again?

    [Response: I don’t think so. The confusion might be because of the way that the estimates are added together. They don’t just take the best guess and do the summation, but rather use the (sometimes skewed) uncertainties for each term and aggregate them into a pdf. I haven’t done the math myself, but I’ll guess that the ‘best guess’ for the total is slightly less than the sum of the best guesses because the uncertainties in aerosols are significantly skewed towards more negative values. It doesn’t look to have anything to do with the solar term. – gavin]

  85. Terran:

    #81 Cheers Chris, reading it now.

  86. Anne van der Bom:

    Steve Fish,
    14 November 2009 at 12:09 PM

    Your question: “What is your plan for all the poor people when fossil fuels become so expensive that they won’t be able to afford the food (this may not be far off)?”

    Although it was directed at someone else, allow me to answer it:

    Ditch fossil fuels as soon as possible in favor of renewables|nuclear (pick your favourite flavour), so the lower demand them will drive the prices lower (or reduce the price increase)

  87. Hank Roberts:

    Alternatives exist.

    “Every bit of the alleged science linking methane and cows to global warming is based on annual cropping, feedlots and herbivore abuse. It all crumbles if the production model becomes like our mob-stocking-herbivorous-solar-conversion-lignified-carbon-sequestration fertilization. America has traded 73 million bison requiring no petroleum, machinery or fertilizer for 45 million beef cattle, and we think we’re efficient. At Polyface, we practice biomimicry and have returned to those lush, high organic matter production models of the native herbivores. If every cow producer in the country would use this model, in less than 10 years we would sequester all the carbon that’s been emitted since the beginning of the industrial age.”
    — Joel Salatin, Polyface farm

  88. Steve Fish:

    Anne van der Bom (~#86, 15 November 2009 @ 6:29 PM):

    My question was regarding the inexpensive food (e.g. corn) that big US agriculture (as one example) is selling all over the world. So, encouraging them to continue their practices with low oil prices, where transportation is a large component of their already high CO2 production, is probably a very bad idea.

    As I hinted at in my #58 comment, helping farmers that produce for a local market to learn (or relearn) sustainable agriculture might be a better alternative. This type of agriculture tends to be more labor intensive, and this works well on lo-tech farms in undeveloped areas.

    There are are universities that have programs that research “organic” agriculture methods for perfecting the required techniques. In my opinion, we need to spread knowledge not CO2, and thereby improve the agriculture economy in poor nations.


  89. JCH:

    Gavin, the old cow puncher in me is ponderin’ on it. I think there is a difference in terms of burping methane while munching away out on a grassy pasture, and I suspect that difference is also, in a lesser way, manifested in the cowpies.

    I’m guessing that which enters and does not end up hangin’ on their growing bones (less operational use), exits.

    They fatten slower on grass, and out it goes – not only more burps and more pies, but possibly richer burps and richer pies.

  90. mike roddy:

    Steve Fish, #79, glad you liked my article. Architects often claim to be green, but most don’t do their homework, and they’re inundated with timber industry BS at trade shows and even in school.

    What did you mean by being unable to find my name link? My email is

    And I’m still surprised that we haven’t heard about Walter. Maybe that means that her work hasn’t been quite accepted by Gavin and others. I’m of course not qualified to make a call on that one, but welcome information on the subject. Margot Roosevelt wrote a very good summary of Walter’s work in the LA Times (searchable on Google).

  91. anna:

    Re Marcus @ #20, thanks for the detailed info, it is most appreciated.

    As to the reason I’m interested in the short term impact of methane, may I refer you to James Hansen and Makiko Sato’s 2004 paper entitled ‘Greenhouse Gas Growth Rates’:

    A reduction in methane (or NOx, or other trace gases) would seem to produce a fairly significant short term effect and would buy us some time to scale up the new technologies that are required to reduce emissions of fossil CO2. And I’m quite happy to follow their lead on this, they’re climate scientists and I’m not!

    I wonder if by averaging the effect of methane over a century, we’re perhaps underestimating the effect that a reduction in methane would have in the short term to buy us the time we seem to need to wean ourselves off coal. I’m not saying that this is a justification of laziness, simply that building many megawatts of new power stations will take time.

    As an example, Australia’s CO2 emissions in 2007 were 448.876Mt, CH4 emissions were 5.603Mt. If you use 72 to calculate the near term (20 year) warming impact as CO2-e, that 5.603Mt becomes 403.416Mt (if you use 88 it is 493.064Mt CO2-e).

    Re Marcus @ #21, I didn’t get the satire, colour me embarrassed! I have apologised to Inferno on his (?) blog. I did skim over the blog the other day, having read several ‘denialist’ blogs, this one seemed pretty similar, in fact one of the posts was very similar to an argument being mounted by a family member recently (that was a fun family dinner). I didn’t read it too closely, I was starting to get too depressed after hanging out at a certain Herald Sun columnist’s blog to subject myself to more of the same. So I missed the crucially placed ‘imaginative’ in the about section. Oops.

    Though I’m obviously not the only one to make this mistake, and I hate to say this but I think that quite a few of the people that I know who would fall for a satirical blog that takes the opposite position. There are gullible people everywhere (of which I am one it would seem, much to my chagrin).

    Which is why we should really leave this to the experts, like Gavin Schmidt, James Hansen etc, etc.

  92. David Horton:

    #89 Possibly the result of a different rumen flora on grass as there is on , say, pelleted food. Also different digestibility.

  93. Aaron Lewis:

    There is a lot of organic material in cowpies. Under feedlot conditions, much of that goes to methane. On pasture, that organic material is more aerobic and dryer. On the high plains, it can be incorprated into the soil and persist for centuries. On pasture, over all, a lot less methane is generated.

    As you do life cycle carbon footprints, remember the energy to related to the fertilizers and pesticides to grow grain. That also brings the synthetic nitrogen cycle into the analysis.

  94. Andrew Hobbs:

    #89 and # 92

    Apparently grass fed cows produce something like 4 times as much methane as high intensity feedlot cattle. And that doesn’t include anaerobic decomposition of the cow pats.

    #89 as for ‘cowpies’. I went to a bad taste party once. Everybody had to bring some food. One guy was fooling around and ‘in bad taste’ grabbed a full sized cake and bit into it. Only then did we realize that he had picked the only iced cow pat on the table.


  95. Richard Steckis:

    Ray Ladbury says:
    15 November 2009 at 6:36 AM

    “Every hybrid, every CF bulb, every light switch turned off or mile not driven makes a difference and buys time.”

    No it doesn’t Ray. Not even close. Those things are about assuaging guilt and not about ameliorating co2 emissions. They make absolutely NO difference to emission levels even if every light globe on the planet was changed.

    You do the math Ray. How many squiggly light globes would it take to save only 1GT of emission? Hybrids are a joke (They still have to be re-charged on mains electricity.

    WAKE UP!! It does not make a difference.

  96. Kevin McKinney:

    Oh, balls, Steckis. If it reduces electricity consumption, it’s clearly going to reduce emissions, too–unless somehow there’s a demand “feedback” of some sort. Do you have any evidence of any such effect?

    A 30-second search turns up this link:

    6.5% for lighting; reduce that by 50%, slice 3.25% off total demand.

    It’s a simplistic analysis, sure, but show why it’s incorrect if you want to convince.

  97. Martin Vermeer:

    > Hybrids are a joke (They still have to be re-charged on mains electricity.

    No, that’s electric cars. Hybrids use gasoline (or diesel), only do so better (smarter) than regular cars.

  98. Ray Ladbury:

    Steckis, every watt of electricity not used saves 3 watts of energy. Increased efficiency matters. It ought to be one thing everyone in the debate on remediation could agree on. Increased efficiency is good for the climate AND for the economy. Hell, Dude, if the US automobile fleet had an average fuel efficiency of ~30 MPG, the country would be self sufficient in energy. I would suggest, Sir, that perhaps it is you who should do the math, [edit – don’t start]

  99. Thomas:

    Yes really Richard. To make a difference we have to get the emissions trajectory to be decreasing a few percent every year. Those quilt assuaging modifications will give us two or three years worth of that change at almost no pain.
    And hybrids (currently not plug ins), do save, they are simply more efficient. Same for plugins or electrics, they need considerably less energy to move around, so much so that they could be powered by coal generated electricity and stil cut emissions. Ever heard of engine breaking (leave your car in gear -or even downshift going downhill to control your speed without braking), the internal combustion vehicle is fighting those considerable loses whenevr the engine is on, the hybrid/electric could be banking the downhill potential energy in the battery.

    Now I’ll give you, that those are only a good start, they won’t take us where we need to go long term. But as they say, a journey of a thousand miles begins with a single step. If we are afraid to take that first step, we’ll never get there.

  100. Andrew Hobbs:

    #96 I agree that lighting changes could reduce consumption significantly.

    However I wonder about the idea that such reductions ‘buy time’. Buy time for what? Surely it depends upon how the world in general reacts.

    Will the world debate the problem in an intelligent responsible manner, come to some reasonable conclusion based upon evidence about what needs to be done and then gets it done.
    Or will the world continue on as usual until some event causes such havoc and disaster, that just about everyone remaining takes notice, demands action and is willing to make drastic changes.

    Buying time makes sense in the former case, giving extra time to implement change and allowing rather slower change to achieve the required goals.

    I am not sure that it helps in the latter, and it is possible it could make the situation worse in the long run. If one has already implemented large numbers of mitigation steps, especially those that could actively remove CO2 from the atmosphere such as reafforestation, while most of the world continues with business as usual then the cupboard will be bare (so to speak) when such efforts are really needed.

    Given past performance I know which alternative is most likely, and it isn’t the first.

  101. Aaron Lewis:

    Re 94: Very true! However, all the carbon for the methane for cattle on pasture comes out of the atmosphere via plants usually without irrigation or synthetic fertilizer. Cattle in a feedlot eat a huge amount of grain grown with large amounts of fossil energy. Thus, cattle on pasture do not add carbon to the bio-cycles. On a full-life cycle basis, the methane from cattle eating grain does add to carbon in the atmosphere.

    One of my very large fears is that sea level rise will drown the industrial complexes that produce agricultural fuels and chemicals resulting in massive reduction of agricultural production and wide spread starvation. Modern agriculture is dependent on fossil carbon. for example, it takes 30 calories of fossil energy to put one calorie of food energy (as California lettuce) on a plate in a NYC restaurant. In the lettuce analysis, the number one consumer of energy is pumping water for irrigation. Number 2 use is the production of chemicals and fertilizer. Number 3 use of energy in lettuce production is field plowing and cultivation. Trucking the lettuce across the country is way down the list. The lettuce analysis puts feeding grain grown on irrigation to cattle in a feedlot in whole different light.

  102. Hank Roberts:

    > 94

    Since most of the methane is from the ponds of manure, obviously cows should be kept in open field pasture but fed high quality grain. I doubt this will be popular. But the methane from anaerobic manure ponds is much greater than that from cow burps. Remember there’s been a huge misdirection by the lobbyists to obscure that.

  103. Doug Sourbeer:

    It seem that we don’t want to address the root cause of global changes. It will not matter if every livestock operation in the world is shut down. Nor will it matter if India uses coal or not. As long as population growth continues unhindered, (and even aided by mass migrations), polution will be an ever increasing problem. It’s not so much what you do, as how many of you are doing it.

  104. mike roddy:

    I’m a distributor for a microprocessor controls company ( that reduces hotel room energy consumption by an average of 35%. You would think every hotel would buy it, especially with tax credits, utility rebates, and energy savings. Payback time is usually about a year. But no- don’t ask me why, though it may be because I’m a bad salesman. The product is only in about 15,000 rooms in the US, but is standard in the rest of the world.

    Re lighting, though, 85% of a hotel room’s energy use comes from the HVAC unit. The rest is fans, TV, and lights. We can control them, too, but it’s minor compared to the heating controls, and normally not cost effective. I’d like to install light shutoffs, and agree that any energy saved is a good idea, but hotels already have flourescents. The action is in software and controls. When a hotel guest leaves, the HVAC shuts off to a setback position. Big, big energy savings nationally are available here.

  105. Ike Solem:

    Coal and the other fossil fuels are the main culprits here, right?

    Let’s say you eliminate all meat production outside of the pre-industrial open range model used by everyone from Saharan goat herders to Finnish reindeer drivers, plus some smaller ‘enclosures’ as per the English & European countryside model. What happens to climate change if that’s all you do?

    1) Coal use would continue to expand as developing nations seek the same kind of nation-wide power grids that western nations have enjoyed for decades. Even in the U.S., reliance on coal has skyrocketed, see Jeff Goodell’s Big Coal (2007)

    “Between 1970 and 2000, the amount of coal America used to generate domestic energy tripled…

    Our consumption is easy to justify: cheap power is important to the American economy, the coal industry provides thousands of jobs, and whatever coal’s environmental problems are, at least coal plants are not going to melt down in some radioactive nightmare or increase the risk that some Middle Eastern terrorist will get his hands on a few ounces of plutonium. But this is the logic of the beer drinker who congratulates himself for not guzzling whiskey. It is not the kind of thinking that leads us to change our lives.”

    2) Shortages of crude oil would lead to a move to dirtier liquid fuel sources, from coal gasoline to Canadian tar sand syncrude to Rocky Mountain shale oil. Those sources require large amounts of natural gas to process into fuel, plus huge volumes of fresh water, and leave massive amounts of liquid and solid waste behind.

    The vision of “The Saudi Arabia of Coal” recently pronounced by Senate politicians would require massive public subsidies for coal-to-gasoline production plants – something that has been very well-supported by both the current and past U.S. Presidents. Obama was among the most vocal Senate proponents of the notion, which provides Illinois a means to convert its very high-sulfur environment-unfriendly coal to marketable gasoline. This is probably the true agenda behind Project FutureGen, as the components are all parts of coal-to-gasoline plants and will be sold on at discount after the “demonstration project” is over.

    With no international treaty with obligations to limit carbon emissions, it will now be possible to move forward with these very fossil CO2-intensive energy projects – from Canadian tar sands to Venezuelan heavy oil to Asian liquified natural gas to coal-to-gasoline projects – without having to risk any pesky lawsuits or legal challenges. These delaying tactics serve little other purpose – for example, with the loudly predicted failure of Copenhagen, the State Department won’t have to take back that permit for Canadian tar sand import pipelines.

    The cover under which all this is being done is carbon capture and sequestration, which will allow all these fossil fuels to be burned without emitting any CO2 to the atmosphere, or so the pet institutions of the fossil fuel lobby claim. Despite all that, no prototypes or energy performance figures have ever been released for any CO2 capture project – just wait 24 years, though…

    Not even the Australian business world is buying it any more:

    Coal-fired power using carbon capture and storage will not play a significant part in Australia’s future energy because by the time it is ready – sometime in the 2030s, the Global CCS Institute says – we will have far more cost-effective options.

    Against that backdrop, livestock emissions are a paltry issue – and consider what would happen if fossil fuels were eliminated, but livestock production was held at today’s levels? You’d probably reach a stable steady state within a few decades, especially if all the factory farms and feedlot operations were eliminated. Clearly, the confined operations and waste ponds are the worst culprits – I don’t think sub-Saharan goat farmers and Asian rice farmers have done anything similar. Just pass laws banning those operations, and then the rise in meat prices will be matched by a fall in non-meat foods – 50% of the corn grown in the U.S. is fed right to cattle, pigs and chickens, for example. Reduce the demand one place, reduce prices the other. Or turn it into ethanol if prices go to low.

    P.S. Noone is going to suggest that countries that grow rice take some kind of “carbon credit penalty” for also producing methane, are they? Think about the overall carbon cycle, and it becomes clear that the fossil fuels are the problem, and that focusing on livestock is just a diversionary tactic… or a very shady marketing campaign for whale meat… sometimes, the Norwegians are just plain embarrassing.

    P.P.S. What does “fair dinkum” mean?

  106. SecularAnimist:

    Aaron Lewis wrote: “One of my very large fears is that sea level rise will drown the industrial complexes that produce agricultural fuels and chemicals resulting in massive reduction of agricultural production and wide spread starvation.”

    I don’t think you need to worry about that. By the time the sea level rises that much, worldwide mega-drought will have already caused massive reduction of agricultural production and wide spread starvation. When the vast grain-producing regions of North America have become deserts, all the “agricultural fuels and chemicals” in the world won’t be much help.

  107. SecularAnimist:

    Ike Solem wrote: “… consider what would happen if fossil fuels were eliminated, but livestock production was held at today’s levels … if all the factory farms and feedlot operations were eliminated.”

    “Livestock production at today’s levels” is absolutely dependent on industrial-scale factory farms, feedlot operations and slaughterhouses, and on abundant, cheap fossil fuel energy. The amount of meat that can be produced sustainably, without those practices, is far less than what is produced today. In the future you envision, animal flesh, milk and eggs would make up a much smaller part of the developed world’s diet (and especially of the “standard American diet”) because there would be less of them produced, at a higher cost. People would eat a much more plant-based diet. Which would be a good development for human well-being, since it would help to reduce the epidemics of preventable degenerative disease that afflict the developed world (and increasingly afflict the developing world as meat consumption there increases).

    As for the developing world, much of the increase in meat production there is tied to copying US-style factory farming practices — with disastrous consequences for the environment, human health, and animal welfare.

    Like the focus on finding ways to keep the world’s vast fleets of cars on the road, the focus on finding some way to maintain diets based on a toxic excess of animal products is wrong-headed and counterproductive.

  108. Hank Roberts:

    Moving to agriculture that doesn’t rely on fossil-fueled corn is a good idea (in part because it removes part of the market for coal and petroleum). Salatin’s model shows it can be done — it could have been done in the 1930s, instead of the path we took, and we’d still have small farm towns all across the east and midwest. States like Louisiana and North Carolina did, wisely, pave the little farm roads, making it possible for the small farmers to get to market in the rainy/muddy weason. Someone should write the alternate history.

  109. Jonathan Mulligan:

    102, Hank some larger operations are harnessing the methane. It may one day be regarded as beneficial to congregate animal waste to do just that.
    If only sustainability was expected of the the fossil fuel industry then this renewable energy source would be greatly valued.

  110. Ike Solem:

    Coal-fired livestock production?

    Secular Animist says that: “Livestock production at today’s levels” is absolutely dependent on industrial-scale factory farms, feedlot operations and slaughterhouses, and on abundant, cheap fossil fuel energy.

    That’s not so – it’s just a restatement of the fossil fuel lobby’s favorite myth, that modern civilization relies entirely on mining ever-dirtier fossil carbon deposits for conversion to fuel, and if we stop we’ll all go back to pre-industrial squalor & starvation. It’s just not true, as any renewable energy expert can tell you – or just look at the dozens of studies that have been done.

    What IS true is that the feed grain delivered to livestock in the United States alone is enough to feed 800 million people. That’s not really the central point either, however…

    How is all that feed grain produced? Industrial technology – ammonia fertilizer, fossil-fueled tractors, electric water pumps run off coal, plus all the fuels used to transport, process and distribute the grain. Going back to animal and human labor is impossible – so are the fossil fuel ‘dieoff’ proponents right?

    More to the point, can we take individual farms and maintain their level of productivity without fossil fuels? Yes. Solar and wind can provide electricity for all growing and processing operations, and solar biohydrogen can be used in the place of natural gas for fertilizer production. You can do this globally, and the sooner the better – so are U.S. agricultural schools looking into this? Not really… their corporate petrochemical partners don’t like the idea at all.

    So, if you can produce the grain without fossil fuels, you can raise cattle without fossil fuels – even in feedlots. However, if agricultural yields drop as precipitation & weather patterns change, than everything must be scaled back. Groundwater pumping can make up for this in some areas, but once the water is gone (or polluted), that’s it.

    Nevertheless, feedlots and factory farms should be banned or vastly scaled back. Essentially, these approaches are just to fatten the cattle – and it’s healthier to bypass the feedlot fattening stage. The meat is leaner and thus pricier, but the feedlot problems (manure, antibiotic overuse, etc.) are avoided. You would probably also see more local distribution and less global trade in “meat products.” Sure, it’s better to avoid meat, but it’s also obvious that it doesn’t have to be a climate problem.

    For example, are sub-Saharan goat herders the big culprits in global warming?

    Definitely not – it’s the so-called “cheap and abundant” coal and dirty crude sources that are the problem, and all the evidence shows that they can be replaced in full with sunlight & wind, direct solar fuels, baseline nuclear capacity, and efficient technology.

    That will require that policy makers start listening to independent & reliable sources of scientific information, instead of to fossil fuel financed lobbyists, think tanks, academics and news media. The main problem there is actually sorting out the honest voices from the fossil fuel industry spokespeople.

  111. JCH:

    Assuming grass fed, when a lone cowpie endures its solitary decomposition on the lonesome prairie, is there a lonely guy out there measuring the methane emissions? I do not want to offend Elsie, but her delicate cowpies are wide and deep. Is there no anaerobic level in them, or is the anaerobic number for livestock methane emissions assumed to be solely from confinement environments.

  112. Hank Roberts:

    JCH, Google Scholar:

    Speculative guess about search terms, just one try as an example of how to look:

    One example from results — there’s much research available to read on this, and I’m sure you can do better with a little effort looking into this
    Methane emissions from danish cattle dung pats in the field

    “The total release of CH4, estimated on the basis of these values, from the dung pats produced by a cow during the grazing season in Denmark is only 0.8–4% of the emission likely to result from the same dung production stored as liquid manure during the same period.”

  113. PHG:


    “More to the point, can we take individual farms and maintain their level of productivity without fossil fuels? Yes. Solar and wind can provide electricity for all growing and processing operations, and solar biohydrogen can be used in the place of natural gas for fertilizer production. You can do this globally, and the sooner the better”

    Can you clarify what you mean by solar biohydrogen?

    Solar, while useful in some instances, is not that practical for northern latitudes due to
    reduced solar insolation, especially in winter.

    Also, most process’s that I’m aware of require heat/steam how is that generated?

  114. Hank Roberts:

    PGH, the answers to broad questions like this can’t be given on a blog in a brief response — you’re asking about an area of research that takes some reading.

    Example of how to look:
    Guessing at search terms in Scholar finds many papers even limiting the search to year 2009:

    Just one example from the first page of hits above, a very good read:

    SWCS – Soil and Water Conservation Service

    Again, just an example of what you can find:

    “… statistics are indicative of several trends in United States and world agriculture. Hanson et al. (2008) discussed eight such current trends, including (1) increased land degradation, (2) competing land uses, (3) focus on single ecosystem service, (4) increased farm size, (5) movement toward commercialization, (6) genetic engineering, (7) global markets, and (8) changing social structure.
    In his discussion of the current status and future trends in American agriculture, Ikerd (2009) argued that the current industrial food system is not sustainable. His premise for animal production was that animal agriculture will be needed to help feed the world in the postindustrial 21st century, and most animals in the future will be raised on grass. His polemic — that the current industrial food system is not sustainable is tenable, and it has far reaching implications for sustainable animal-based production in the United States. Other important considerations that must be dealt with to ensure a sustainable animal-based agriculture include global markets, fossil-fuel energy use, and water shortages. Before discussing these impacts, we will first address the issue of sustainability….”

  115. PHG:

    Thanks Hank.

    I’m quite new to this commenting thing so I appreciate your patience.

    I’ll check out the references.

  116. Lawrence Coleman:

    Here’s the state of play in Australia-climate wise… Many of our major cities are reaching critical levels of fact except for Hobart in Tasmania and Darwin in tehe northern territory every city is struggling..Brisbane has not too long ago been given a much needed top up, but Adelaide in SA is Critical with Perth in WA not far behind, Sydney’s water supply is becomming precarious and Melbourne also. A large farming town west of Brisbane – Toowoomba has it’s reservour dams now less than 9% full and dropping. Australia cannot cope with this trend of drying for much longer. Water desalinisation plants are being built in Queensland but they pose a significant ecological risk to the coastal fisheries eg..high salt concentrations of the plants waste get pumped only a 1 km out to sea assuming the natual currents will distribute the salt. Australia’s longest and most economically important river he Murray is almost dead by the time it reaches victoria and SA. The last two winters at least have been exceptionally mild in the SE queenland area where I live and the heat waves have been far more intense and longer lasting on record. It’s currently 37C outside and in the computer room where I’m about a dedicated amateur climate reporter! So this is how CC is affecting us right now in Australia and the long term prognosis isn’t good.

  117. Richard Steckis:

    Ray Ladbury says:
    16 November 2009 at 9:35 AM

    “Steckis, every watt of electricity not used saves 3 watts of energy. Increased efficiency matters. It ought to be one thing everyone in the debate on remediation could agree on. Increased efficiency is good for the climate AND for the economy.”

    Ray. Antrhopogenic CO2 production world wide is estimated at about 19GT. Changing domestic energy efficiency by say 3% in one country will make ZERO effective difference to the world wide production of CO2 most of which is generated in construction, mining and manufacturing industries.

    Again Ray, DO THE MATH. The trouble with a lot of you Physicists is that you reduce to x watts not used save y watts energy instead of looking at the big picture and determining the statistical importance of that assessment (with relation to overall energy consumption) in the real world as she is lived in.

  118. Richard Steckis:

    Lawrence Coleman says:
    16 November 2009 at 9:45 PM

    “Here’s the state of play in Australia-climate wise… Many of our major cities are reaching critical levels of fact except for Hobart in Tasmania and Darwin in tehe northern territory every city is struggling..Brisbane has not too long ago been given a much needed top up, but Adelaide in SA is Critical with Perth in WA not far behind”

    Lawrence, this is not a climate change problem. This is a population problem. Australia (I live in Perth) has already exceeded the carrying capacity for a human population (estimated by CSIRO at about 10 million). Australia is the second dryest continent on earth and increasing the population will only exacerbate the perception that climate change is the problem instead of the insatiable demands of an ever increasing population.

    You also say:

    “The last two winters at least have been exceptionally mild in the SE queenland area where I live and the heat waves have been far more intense and longer lasting on record. It’s currently 37C outside and in the computer room where I’m about a dedicated amateur climate reporter! So this is how CC is affecting us right now in Australia and the long term prognosis isn’t good.”

    It is my understanding that SE QLD has had good rainfalls this year. Northern NSW has had exceptional recent rainfall. Heat is part of our summers or have we forgotten. And this is NOT an example of climate change, it is an example of an anomalous weather event. Is it not amazing that whenever the weather provides record heat it is blamed on climate change but when the record goes the other way that is just natural variation? Please do not let perception cloud judgment.

  119. CTG:

    #105 Ike

    “Fair dinkum” in that context is probably best translated as “genuine” or “truthful”.

  120. Timothy Chase:

    Ray Ladbury wrote in 98:

    Steckis, every watt of electricity not used saves 3 watts of energy. Increased efficiency matters. It ought to be one thing everyone in the debate on remediation could agree on. Increased efficiency is good for the climate AND for the economy. Hell, Dude, if the US automobile fleet had an average fuel efficiency of ~30 MPG, the country would be self sufficient in energy. I would suggest, Sir, that perhaps it is you who should do the math.

    Richard Steckis responded in 117:

    Ray. Antrhopogenic CO2 production world wide is estimated at about 19GT. Changing domestic energy efficiency by say 3% in one country will make ZERO effective difference to the world wide production of CO2 most of which is generated in construction, mining and manufacturing industries.

    Again Ray, DO THE MATH. The trouble with a lot of you Physicists is that you reduce to x watts not used save y watts energy instead of looking at the big picture and determining the statistical importance of that assessment (with relation to overall energy consumption) in the real world as she is lived in.

    The math…

    Total US CO2 Emitted for 2007: 6103.4 million metric tons
    Fossil Fuel Combustion: 5735.8 million metric tons
    Percent CO2 Due to Fossil Fuel Combustion: 94.0

    … from EPA 430-R-09-004
    1990 – 2007, ES-7 (pdf pg. 30), Executive Summary

    World CO2 Emissions for 2007: 28,431,741 thousand metric tons
    US CO2 Emissions: 5,752,289 thousand metric tons
    US Emissions as Percent of Total: 20.2
    List of Countries by Carbon Dioxide Emissions

    Increasing energy efficiency in the US by 3% would save 0.57%. Increasing US energy efficiency by 50% would save 9.49%.

    Energy efficiencies in the US would save money. Energy efficiency strategies would be replicated and energy efficiency technologies would likely be sold to other countries, resulting in higher profits and rates of employment domestically.

    Assuming the percent of world CO2 emissions due to fossil fuel combustion for the world was similarly 94.0%, a 3% increase in energy efficiency in all countries would result in a reduction in world CO2 emissions of 2.82%. A 50% increase in energy efficiency would imply a 47% reduction in CO2 emissions.

  121. Timothy Chase:

    CORRECTION to my previous post

    If one were to speak precisely, rather than saying “increasing energy efficiency by [X]” I should have said “reducing energy use by [X]” as this was the actual math used. Calculations specifically in terms of energy efficiency would give you somewhat different figures — although qualitatively the results would be much the same.

  122. Paul Segal:

    Hank #112 quoted
    “The total release of CH4, estimated on the basis of these values, from the dung pats produced by a cow during the grazing season in Denmark is only 0.8–4% of the emission likely to result from the same dung production stored as liquid manure during the same period.”

    And that’s probably ignoring what Dung Beetles will do in Australia. Maybe 7 years ago we used to have a bad fly problem with all the cattle around our place on the mid north coast of NSW, then came the Dung Beetles. Now you are lucky to see anything remaining from a cow pat on the ground after more than 2 days, it has been ploughed in by the beetles, almost no flies too. The dung is eaten by the beetle larvae. The introduction of foreign dung beetles was the work of the CSIRO (Aussie dung beetles aren’t built for large dung piles), with the help of farming groups and farmers.

    The other tack is to attack the source of the methane production in cattle.

    More recently the CSIRO have also been doing similar work for sheep.

  123. chw:

    In 2000~2009, Arctic and Siberia methane levels are also relatively stable: 1850->1890 ppb (a little higher than aggi_2009.fig2.png ~1780ppb, though)

    But i am worried about the warming would (soon) trigger mass methane release in these area, as described in:

  124. Ray Ladbury:

    Steckis tells me to look at the big picture. Now, never mind the delicious irony of this coming from a guy who bites like a pitbull on any brain fart coming out of the denialist community. What really matters is that Steckis is reducing the issue to the energy saved by a single CF–utterly ignoring the fact that if we reduce energy consumption, we won’t be building all those new coal-fired power plants that will spew out CO2 for the next 30-50 years…utterly ignoring the fact that increased demand for energy-efficient technologies spurs further development and makes them more affordable…and utterly ignoring the fact that once we pass the point where natural GHG sources kick in with a vengeance, it’s game over.

    Sorry, Steckis, I have done the math, and the math says that small changes by large numbers of people make a big difference. In fact, they can make all the difference for whether we find a solution to global warming or provide our own answer to the Fermi Paradox.

  125. David Horton:

    #118 “whenever the weather provides record heat it is blamed on climate change but when the record goes the other way that is just natural variation”. Um, the records aren’t “going the other way” Richard, that is the point. Region after region, month after month, year after year in Australia we keep seeing record high absolute temps, record high averages, record high sequences, record high lows, and so on. Don’t remember too many records being set in the other direction, do you? Oh, and population? Sure, but pressures from population increase on water supply doesn’t negate pressures on water supply from record low rainfalls, record low average rainfalls. In addition we have had record extreme events in storms and floods. And if you were paying any attention to weather patterns you might notice that rainfall in southern Australia is dropping because fronts are constantly being pushed to the south these days as the continent warms. Doesn’t mean you might not get high rainfall in the north of the country as a result of climate change – predicted to, actually. You could not live in rural Australia over the last twenty years without understanding that there has been a fundamental change in climate, and therefore weather patterns.

  126. dave p:

    Re 125
    In australia will the tropical rainbelt move further south as a result of climate change? So Northern New South Wales will become like Queensland, and rain will push further in to the central deserts.

  127. Jeff Baranchok:

    Don’t skeptics ever post here?
    No, seriously.

  128. David Horton:

    re 126 There is a trend on the east coast for tropical fish and other marine species to be found further south as waters warm, and on land tropical diseases like Dengue and Ross River fevers seem to be moving south with the associated mosquitoes. I’m guessing that other insect species and presumably land vertebrates are also extending their ranges south, though this would be slower, and I don’t know of studies showing this yet. So there will be a kind of domino effect where Melbourne becomes more like Sydney, Sydney more like Brisbane, Brisbane more like Townsville. I don’t think species movement can happen on the west coast because of the desert which reaches the coast there. And I’m guessing that the desert regions of central Australia will become warmer but not wetter.

  129. Hank Roberts:

    To understand the political issues around the recent law forbidding the EPA from addressing controlling methane big agribusiness, this will help. Be patient — read it down to the end. Check the references.

  130. Geoff Russell:

    Aron#101: Methane from livestock (and us) doesn’t increase the carbon in the
    atmosphere but it does increase its forcing for a decade or so. Consider the
    limiting case where all the CO2 is magically transformed to CH4, the
    carbon is the same, but (ignoring energy spectrum issues) the planet is stuffed.

    Hank#102: According to the Edgar global CH4 emissions database

    methane from manure is about 10% of methane from enteric fermentation.

  131. Lawrence Coleman:

    Don’t worry about Stekis..’There is none so blind etc…’..You would think(pardon the pun) that if everything else fails you could at least rely on good ol common in point. Carl Sagan first opened my eyes to the fragility and depth of the biosphere by the basketball analogy which I’m sure everyone is familiar with. Our Atmosphere is but an extremely thin film of various gasses mainly nitrogen around a massive body. Why can’t Stekis visualise what happens if we keep pumping simply enormous quantities of pullutants into our breathing bubble decade after decade..doesn’t take a rocket scientist to work that one out mate!
    Here I must in all fairness hang my head lower..Australia is the worst polluter and CO2 producer/source per capita in the world as latest findings prove- 4.5 times the global average. Even though the world puffed 2% more CO2 into the air this year (down from 3.5% in preceding years coz of the GFC) we continued to sail ahead as we probably were not as effected by the GFC as most other countries so it was buisness as usual for our factories. So could it be what the world needs to buy us all some time is a continuation of the GFC?

  132. John (Burgy) Burgeson:

    I am still confused (some people will say this is an inherent conditio).

    Let me post the question as a gedanken experiment.

    Suppose there had never been any global land-based temperature reporting stations. Would the case for AGW be just about as strong anyway?

  133. Kevin McKinney:

    Burgy, I think an answer (even a “gedanken answer”) requires redefinition of “global land-based temperature reporting stations,” which to me is a confusing formulation. (How can they be “global” if they are solely “land-based?” And “reporting stations” would seem to refer to individual sites, which “global” really doesn’t–at least, not in the same sense of the word.)

    However–Guy Callendar felt he’d identified an anthropogenic warming signal back in the 30’s. (Consensus on that seems to be that the trend was there, but it wasn’t primarily anthropogenic at that point.) To do that, he basically created his own (tiny) global dataset. And James Hansen (and co-workers, of course) created GISS in order to investigate the AGW hypothesis.

    So, historically, it seems that the AGW hypothesis gave rise to global datasets–which, upon investigation, strengthened the hypothesis.

    In a way, this process negates your presupposition: once one has asked “Hey, I wonder if all this CO2 could be warming our climate up?” it is a natural step (for the right sort of investigator, at least) to create the data set needed.

  134. John (Burgy) Burgeson:

    Kevin: Thanks for the answer — but it was to a question I did not ask.

    If my question had been “Were the land based temperaure recorders” instrumental in getting the AGW idea rolling, I think you answered “yes.”

    Bi=ut my question is about a hypothetical world — a world in which land based remperature recorders do not exist. Given this world, would the AGW claim be as robust. I glean from your answer that it would not be, in which case how much weaker would it be?

    I have a contact who thinks that the entire IPCC AGW claim — for the most part — starts with and is currently based upon land temperature measures. I think him wrong on this; the questionis — how wrong?

  135. Marcus:

    “If my question had been “Were the land based temperaure recorders” instrumental in getting the AGW idea rolling, I think you answered “yes.””

    Be careful how you phrase this: the AGW idea started rolling in the 19th century with Arrhenius, who posited the impact large increases in CO2 could have on global temperatures based on, I believe, theory and some paleo data.

    In this gedanken experiment, where everything about the scientific world is the same except that there is no land-based temperature record, I would argue that only a few things would be weaker:

    1) Attribution is harder with less data. Sea-surface temperature records, ocean heat content, and radiosonde/satellite data might be sufficient, but usually if you have less data it is always hard to have the same amount of certainty.

    2) Climate sensitivity deductions based on the instrumental record: same argument where less data would almost certainly mean broader pdfs (and these pdfs would most likely stretch more on the upper end than on the lower end, since that’s the end that’s hard to pin down anyway). Here, though, there are more paleoclimate and theoretical studies which yield similar answers to the instrumental records.

    3) Any sort of regional temperature matching to impacts: if we don’t know the surface temperatures in a region, it is kind of hard to discuss how things like plant migration are responding to local temperature.

    But really, there’s so much data that is consistent with a warming world besides the land-temperature data, that outside of a few exercises like the above I just don’t see major effects on the core tenets of AGW theory from throwing out the land data set.


  136. Hank Roberts:

    John B, how do you miss this kind of information after being around here for so long? Why not give us your best answer to this friend of yours — surely you can come up with a good response yourself, just by reading the topics here

    For example:

    and the material mentioned in them, for example

    And so much else. Why just post these extremely naive questions from people who haven’t bothered to make any effort to educate themselves — without showing what you’ve already learned and how good an answer you can come up with from your time spent here?

    You’d be a good example for the kids who come here needing homework help.

    Take your guide from this much recommended page:
    Heck, show it to your friend, he could start off just following those suggestions and make great progress.

  137. Hank Roberts:

    PS, if his next question is “but what if we didn’t have calendars so we couldn’t tell that there are changes in the timing of the bird migrations and flower opening” — show him a picture of Stonehenge.

    If his next question is “but if we didn’t have rocks” — you can reassure him that he will always have rocks.

  138. Barton Paul Levenson:


    “Very wrong.” AGW can also be seen in sea-based temperatures (from ships and buoys), borehole temperature records, balloon radiosondes, satellite observations, tree lines moving toward the poles, earlier hatching dates for the eggs of insects/fish/frogs/reptiles/birds, tropical diseases moving into temperate zones, glacier retreat, melting ice caps, more droughts in continental interiors, more violent weather along coastlines, and increased IR opacity of the atmosphere.

  139. Paddy:

    I’m often amazed at the lack of thought presented by the vegetarian lobby with regard to methane emissions. They tend to forget that ruminants are not new to planet earth, and as someone pointed out earlier, millions of ruminants used to roam the wild before domestication. Yes domestication, not creation.
    They conveniently assume that uneaten grass would not produce methane in its lifecycle.
    It also seems current practice to compare apples with oranges, 72 times or 88 times CO2 factoring for instance with 20 years the chosen timeframe. A timeframe which is meaningless given the half of methane being 7 years.
    It shouldn’t be forgotten that direct meat and dairy produce is not the only useful result of feed inputs. Possibly because we view the waste as waste and not potential energy or fertiliser, and ignore the leather biofuel etc part of the energy equation.

    A focus on agricultural methane, some 33% of emissions of a gas said to be 18% of the AGW problem makes it a minnow compared to fossil fuel consumption. Comparable with cement production.

    In the last 20 odd years methane levels have increased 100ppb, and should we apply the 20x warming factor this compares well to the ANNUAL CO2 2ppm approx increase we’ve seen recently.

    On top of that we’ll be told cattle produce as much warming as transport, but don’t mention that transport is factored into that equation, double dipping in my opinion. Nor is it particularly fair considering we nearly all eat animal products but only a small proportion of the worlds population have cars or fly in planes.

  140. mike roddy:

    Richard Steckis, #118: “most CO2 emissions are caused by construction, mining, and manufacturing”.

    No. Do the math, and check out the EIA tables. The US is different, but not that different. In the US, manufacturing of all products accounts for 14% of our CO2 emissions. Mining of all minerals is a low figure, certainly less than 100 million tons (1.6%), though it’s difficult to find in the tables. Construction emissions are trivial compared to heating and cooling the buildings, and the emissions of construction material manufacturing are contained in the 14% figure.

    The exception is clearcut logging to produce two by fours for home construction (about 200 mmt CO2 annually), but that’s a separate issue that could be solved if we substituted other materials.

  141. dave p:

    re 128
    I remember now reading reports a year ago of heavy rainfall in North West Australia, which is normally desert. Has this continued?

  142. SecularAnimist:

    Paddy wrote: “I’m often amazed at the lack of thought presented by the vegetarian lobby with regard to methane emissions. They tend to forget that ruminants are not new to planet earth, and as someone pointed out earlier, millions of ruminants used to roam the wild before domestication. Yes domestication, not creation.”

    With all due respect, I am amazed at the lack of thought that goes into equating the environmental impacts of modern, industrialized, fossil-fueled factory farming of animals not merely with the impact of pre-industrial grazing practices, but with the impact of wild ruminants prior to human domestication of animals.

    In the USA alone, more than nine billion animals are raised and slaughtered for food every year, virtually none of them in conditions or on diets that remotely resemble those of pre-industrialized grazed animals, let alone pre-domestication ruminants; and the vast majority of them in fossil-fuel intensive, massively polluting “confined animal feeding operations” a.k.a. industrial factory farms.

    If you want to argue that animal agriculture can be “reformed” or scaled back or regulated or somehow managed so that its impacts are reduced to those of the pre-factory farm era, that’s one thing.

    But it’s an entirely different matter to turn a blind eye to the detrimental effects of industrialized livestock production and pretend that, for example, the impacts of the modern day beef industry in the USA are no different than those of the wild bison population some 10,000 years ago.

  143. David Horton:

    #141 No. But NE NSW has had a number of major floods this year.

  144. Phil Scadden:

    Paddy, before jumping to conclusions about emissions accounting and double dipping, you could perhaps check out how it is actually done before criticizing?

  145. Hank Roberts:

    Geoff noted
    > methane from manure is about 10% of methane
    > from enteric fermentation.

    Good number. I think that’s comparing cowpies (in the pasture) to cow burps — neither is a big issue.

    From high density cow and pig industry operations, it’s big — and measurable, and quantifiable. That was the basis on which EPA had issued a final regulation on reporting.

    I still wonder if this wasn’t partly done to block the development of agricultural methane as an alternative to fossil fuel — to preclude a competitor from developing in the market. The methane-capture-as-fuel systems would merit subsidy both by directly reducing methane, and by replacing fossil fuel use (not to mention improving the smell downwind of the big pig farms).

    I hope some journalist has been working on this. No doubt it’s been written up somewhere. Anyone know the ag journals?

  146. Steve Fish:

    Jeff Baranchok (~#127, 17 November 2009 @ 4:20 PM):

    What you ask depends upon what you think a honest skeptic has to say. What do you think? I don’t really expect an answer, but this interests me.


  147. Geoff Russell:

    Paddy#139: It wasn’t the vegetarian lobby that wrote Livestock’s Long
    Shadow, but a group within FAO advocating (or at least predicting) increased
    meat production:

    Another estimate of the emissions due to beef in Australia (page vii) puts
    it at double that of aluminium (using the 100 year methane GWP) and this
    estimate includes NO transport or other indirect emissions.

    As for the “we all eat animal products”, this needs to be quantified. Beef
    provides just 1.3% of global calories (FAOSTAT) but is a driving force
    for deforestation in many places from my country (Australia) to Indonesia
    and South America. All up, livestock is 700 million tonnes
    of biomass that is supported to provide a mere 17% of
    global calories (unevenly) to 330 million tonnes of human biomass.

  148. John (Burgy) Burgeson:

    Thanks, Marcus for a good answer (particularly your closing paragraph.” I have been telling my friend essentially this answer for some time now.

    Thanks, Barton, for your comments. It seems to sum up the evidences well.

    Hank — I am well aware of the evidences. What I was doing is exploring how important one of these was. I have not seen this addressed as well as Marcus did in his reply. I do appreciate the links and will have a look at them.


  149. mike roddy:

    Ray Ladbury, or anyone else, please send me the link or reference for the statement that every watt saved is worth three watts. I’m in the energy efficiency business- hotel room keycard RF systems- and would love to use that information in my marketing. You can reach me at

  150. JCH:

    “Good number. I think that’s comparing cowpies (in the pasture) to cow burps — neither is a big issue. …”

    Hank, I think it’s the percentage of all livestock methane that is due to manure – all settings. 90% of all livestock methane is burped, and the vast majority of that is from ruminants – cattle, sheep, and goats.

    They spend the majority of their life spans in pastoral settings, and it’s by a fairly wide margin.

    So I would think pastoral burping has to be the largest source of bovine methane.

  151. Paddy:

    Geoff, I’m aware who wrote the Livestocks Long Shadow, I’m questioning whether or not it’s valid to include livestock and meat transport emissions and then compare the whole lot to transport emissions.

    I thought Australian landclearing had virtually halted under current laws. I do know there are huge tree plantations happening over there so it must be a net zero by now. The US claims to be a net carbon sequestor with regard to landuse change, and Europe has been mostly cleared for centuries.

    You mean the whole 5 Aluminium mines and 7 smelters in Australia are responsible for the same amount of emissions as 28 million cattle? How did you account for the exported bauxite?

    Beef providing 1.3% of calories seems a bit low, but as a billion odd chinese eat primarily pork and chicken, and most of India’s population worship their cows (india has 20% of the worlds cattle) it may well not be far off. Of course cattle emissions include dairy cows, that “beef” doesn’t. I’ve heard goat meat is the most consumed meat in the world, how it’s emissions compare per kilo of meat would be worth looking up. Can follow link in 144, I didn’t give goat emissions more than a glance, somewhere around 10% of cattle per head from memory.

    144, I wasn’t refering to IPCC, Geoff knew what I was talking about. I did read through the 87 pages to check though. Thanx.

  152. Paddy:

    142, well secular A, you’ll have to humour me, it’s mostly cattle I’m refering to, they’re the main animal we associate with methane emissions. Now the US had around 100 million cattle and calves last year and I’ve seen figures estimating Bison numbers from 60-80 million head pre-humans and which number less than a million now. It doesn’t really matter from an emissions view how many are slaughtered each year, it’s the amount that are alive at 2 calves living 6 months each won’t emit more CH4 than 1 living a year. Less probably.
    From IPCC figures Buffalo, which I believe are similar to bison, have similar yearly emissions to cattle.

    You may also note that the higher the quality of food, such as in feedlots, the lower the emissions. Even moreso on a per kilo gained basis. Now I’m no fan of factory farming, nor do I raise livestock, but lets condemn it on a just basis and also remember that cattle usually are feedlotted for only for a few months of their lives. Alebit a short life.

    9 billion is a huge number for sure, I don’t think there is any doubt that people take those deaths for granted and without due respect.

  153. Brian:

    Could the explanation for increased tree growth in recent years be, increased levels in CO2 and not temperature. Tests have shown conclusively that plant growth increases when in a high CO2 environment. Panic over.

    [Response: See here. – gavin]

  154. Barry Day:

    True!Emissions from 9 billion cattle is a huge and are the main animal we associate with methane emissions.

    Lets get cracking and see if we can double that number seeing we URGENTLY need a “Solar – Grand Minima – Preparedness Plan i.e. Little Ice Age Preparedness Plan”

    James A. Marusek

    Nuclear Physicist & Engineer

    U.S. Department of the Navy, retired

    From the pdf
    “Mankind has been down this road before and we will go down this road again and we will survive.
    The last time we faced this type of disaster was over 300 years ago, as a result it has almost
    been erased from our collective memory.
    A solar “Grand Minima” produces a time of great hardship, a time of significant
    natural global cooling, a time of great famine and starvation and a time of major epidemics.

    The threat from a quiet sun is describe in the Solar Grand Minima Threat Analysis available at:
    This Preparedness Plan is a companion document to this analysis in which the threat is described in substantial detail.
    There are several lessons learned from studying very early global cooling events in Europe.

    * The onset of these conditions can be very abrupt and very severe.
    * A decline in food production due to:
    – Dramatic increase in days with overcast skies.
    – Decline in the intensity of sunlight.
    – Decline by several degrees in global temperature
    – Regions of massive rainfall and flooding
    – Limited regions experienced droughts
    – Shortened growing season
    * A string of major and minor famines
    * Malnutrition lead to weakened immune system. Produced influenza epidemics.
    * Reoccurrence of plagues such as the Black Plague.
    * Lack of feed for livestock
    * Parasites (i.e. fusarium nivale), which thrived under snow cover, devastated crops.
    * Grain storage in cool damp conditions produced fungus (Ergot Blight). Contaminated grains
    when consumed caused an illness (St. Anthony’s Fire) producing convulsions, hallucinations,
    gangrenousrotting of extremities.
    * Flooding created swamplands that became mosquito breeding grounds and introduced tropical
    diseases such as malaria throughout Europe”.

    Lets concentrate on the real problem we are about to face.

  155. Greg Robie:

    This thread, by becoming animated (pun intended) about the methane associated with the husbandry of ruminate animals for meat and dairy, dropped consideration of the Arctic as a source of atmospheric methane. The focus ruminate animals is good. This an important source of atmospheric methane that can be addressed by modification of human behavior. To control anthropogenic methane creation, by mitigating/transitioning away from ruminate animals for meat and dairy, is a wedge of the GHG emissions that needs continued redressing. Knowledge, such as has been shared in this thread, is important for doing so intelligently. I would add to that discussionthat just as the developed world, and particularly the US, is addicted to ‘cheap’ oil, the urban/suburban American is addicted to cheap food. Just as vested interests in fossil fuel industries are resisting and manipulating how a price is being put on carbon to protect the profit of their business model, it should be expected that putting a price on agriculture-based methane will be resisted and manipulated. Urban/suburban consumers will be in conflict with rural producers concerning who gets saddled with the costs, and how they are paid for. Fairness will be argued–if differently—by both as a reason the ‘other’ is avoiding responsibility. Just as our government is doing extraordinary interventions to flash-freeze the economic collapse in the hope that such will restart economic ‘growth’ and, thereby, tax revenues to service its deficit spending model of economic growth, government will want to control the CPI—to which many of its unfunded costs are pegged—in its effort to avoid insolvency. Government that is so threatened will be a partial arbiter of competing short-term self-interests in both these matters.

    But, going back to the Arctic and atmospheric methane, there seems to be more we don’t know, than what we do know, concerning the Arctic as a source of methane. For example chw (#123) can link to ‘stable’ average measurements of atmospheric methane at four Arctic measurement stations over the past decade and feel that this confirms Gavin’s assertion that the recent return to increasing atmospheric methane is an “uptick.” The same stability appears to be true of Antarctic station measurements, only those measurements are about 150 ppb lower. At both poles there is a seasonal variation of 60-80 ppb, with the Arctic showing a greater increase in this variability as the past decade has unfolded. Since the air in the atmosphere gets blown around a bit, this use of average figures is likely the least helpful measurement if one is trying to sort out what is happening, rather than wanting to not see a problem; to miss the complexity that a reliance on averages masks. Since methane has a life in the atmosphere of about 10 years, and the Northern Hemisphere seems to ‘pump’ its methane south in a seasonally driven dynamic, and the ~40 ppb rise in the concentration of methane is about half the seasonal variation, together these seem to make a point that is just to opposite of proof that it atmospheric methane is stable in the Arctic, but rather, the ‘uptick” is the “smoking gun” of the methane time bomb has been detonaged.

    Mike Roddy (#8) points out that Kathy Walter’s work has been left out of what was included in this blog post. The report from the British research vessel studies in the summer of 2008 (published this past August) are also not included. Christopher Hogan (#12) points out that the last in-depth coverage of atmospheric methane was in 2005—before the ‘uptick’. Marcus (#42) notes that there is a lot that is not known—an observation that I wold concur with.

    Since I posted my comment #37—reposted below—a person from SEI looked into critiquing it. He told me that he lacked the expertise, and that none of his colleagues were able to provide “insights into the observations” He recommended this reposting. While this thread is getting dated, there is little being covered about Arctic methane. Therefore I hope those who are still looking at this thread, or those who find it via searches on the topic, can critique the following and/or contribute to this thread relative to the Arctic as a source of atmospheric methane.

    lightly edited (for clarity—writing is not a strength) repost of comment #37:

    I would value critique on the following observation concerning the methane “uptick.” When Revkin posted the BP example for capturing methane at gas wells at dotearth 10/22/09-about a gas field going from 4 billion cuft/yr to 10 million cuft/yr.-I realized policies aimed at controlling methane may have been far more successful than the tabling of methane would indicate. That decade long tabling, which the ‘uptick’ relates to, is generally assumed to be due to plugging leaks in gas lines; changes in rice cultivation, and capping landfills. It relates to a measurement of the average level of methane in the atmosphere.

    The BP example may be extreme, but some of the plugs in the former Soviet Union gas lines may have been as dramatic as well. A cursory look at off set projects engaged in under Kyoto suggest a lot of them are landfill capping projects. Given that in Siberia methane was 5 times above background levels in 2003 and in the summer of 2008, up to 100 times greater over areas of the continental shelf in the Arctic, it occurs to me that the mitigation efforts may have masked an ongoing exponential increase in the release of methane in the Arctic.

    The distribution of methane in the atmospheres is strongly weighted to the northern latitudes. In the winter it seems to migrate north, being carried into the Arctic by the same atmospheric condition that gets other pollutants from the temperate latitudes up to the Arctic. With methane having about a 10 year life span (and Lynn #23, I have read that methane first become ethane on its way to becoming CO2 and water), such also suggests that the mitigating policies for CH4 have been more successful than appreciated.

    There is a dearth of scientists studying methane. I heard it reported from Copenhagen this past March that there are only 20 world-wide. Clearly, what funding there is has been focused on studying CO2. To the degree careers follow the money, such may explain both the lack of scientists and funding. The focus on CO2 would also explain why the renewed increase in CH4 might be labeled only an uptick.

    As I consider the changes in climate occurring in the Arctic, a factor I can see in play among all the others-and feeding all the others-is the overlooked ongoing methane increase. Are there any huge oversights in this analysis? If not, could it be further critiqued so we don’t continue to miss it?

  156. JCH:

    There are not 9 billion cattle. The US has around 96 million beef animals – cow-calf operations -, and around 20 million dairy cows. The world population of cattle is around 1.3 billion. There are roughly 65 million hogs in the United States – not counting the ones with extended forks. Of course, the US also imports a great deal of meat, so some of theirs is really ours, too.

    The 9 billion slaughtered for consumption in the United States is mostly poultry – not meaning to diminish the life of a chicken.

  157. Richard Schwartz:

    Re # 50–There are several effects that may have implications for the apparent leveling off of the temperature in the 2001-2009 period. First, it seems to have been established that the solar forcing has undergone a small decrease on average, but this alone probably cannot cancel out the expected effect of the greenhouse warming. A second aspect is that much of this period was dominated by the natural La Nina pattern which tends to produce cooler temperatures, at least on regional scales. A third aspect is the industrialization of China and increase of particulate emissions, the residue of which has been reported in the Western U.S. snowpack. These emissions could well be having some impact by decreasing the solar flux reaching the earth’s surface.

  158. Hank Roberts:

    Some numbers:

    Methane released from enteric fermentation
    Assessment per region and livestock production system
    Resulting total of 86 million tons CH4 per year

    Methane released from animal manure
    Assessment per region and livestock production system, using updated emissions factors
    Resulting total of 18 million tons CH4 per year

    Resulting Overall Contribution
    About 2.2 billion tons CO2 equivalent:
    37% of total anthropogenic CH4 emissions

  159. Greg Robie:

    Paddy (#152), this study$foragebeef/frgebeef.nsf/e5ae854df3230ce787256a3300724e1d/30242e114ec84f8487257162006b48b0/$FILE/GHGforagediets.pdf indicates just the opposite of what you have stated. It says, if I’ve read it correctly, that a lower quality diet produces 46% less methane, but no difference in methane generation from the manure pack (but the lower quality feed produces less manure). This study, in feedlot conditions, suggests that, depending on how much quicker the force feeding of a high protein diet is for finishing a beef creature to marketable size, feedlot operations create more methane. The difference would be influenced by pasture management/conditions and weather factors. In this study, , such resulted in .2 kg/day lower growth rates but greater profitability for the farmer (two other studies are referenced in this report with .47 and a .45 kg/day differences in weight gain during finishing. Regardless, the manure pack is a feedlot phenomena. The anaerobic decomposition occurring in the pack would not occur on the range.

    When fossil carbon footprint costs are factored in for growing and transporting the grain for the feedlot model, in addition to methane production, the feedlot business model is in trouble. Add in the carbon sequestering that free range cattle help the soil pull off and pasture feed remnants gain points. Back out federal subsidies for grain production (that help keep the CPI low) and isn’t the feedlot business model an economic joke AND a GHG production amplifier?

  160. JCH:

    Greg, I’m just a cowboy, but that study is comparing two formulated diets in a feedlot. You will note that the high forage diet includes a significant sunflower seed portion. Out on the range, the only way cows could get sunflower seeds would be to stage a break out and walk to the nearest convenience store. It’s possible to supplement a range diet, but to do it to the extent in that study – I suspect it would be very expensive and problematic. It takes a lot of CO2 to put sunflower seeds into a pasture.

    I think it is pretty well established that a standard pastoral diet produces more methane than a customized diet. I read a study on caribou, and their methane production went way up in the winter when they had to start eating woody plant material. I would not be surprised if the same were not true of cattle. As the food quality of the pasture diminishes, methane may go way up.

  161. JCH:

    Greg, the tests I’ve read about – out on the range – may not demonstrate that to the extent it appears. The pies dry out, and that is when the tests stop. That’s when we started throwing them at each other. Then you get precipitation. What happens then? Also, if you supplement their range diets with minerals and feed designed to reduce methane, they congregate around that feeding station and you get a pretty deep pile in no time, which they keep wet with urine.

  162. Greg Robie:

    JCH, cowboys, due to being out in naturally complex systems (as opposed to climate controlled, artificially lighted ivory towers) can, by mirroring their environment, know more; can think more complexly. Consequently, I would trust the reasoned thinking of the cowhand’s seat of the pants understanding over an academic’s hypothesis in the application of Occam’s razor—though an academic, having more ‘enlightened’ hours in the day, might read more; read better.

    I didn’t see the point you’ve made about sunflower seed. I did see that it was a short study—and feedlot-centric. The second study I linked to was an attempt to quantify how much longer a pasture finished animal might take to reach slaughter-ready condition in terms of methane production and decrease the 46% ‘savings’ a diet of ruffage might have. The range, a .2 – .47 kg/day difference during finishing does eat into the ‘savings.’ I remember reading somewhere that a steer can be raised to slaughter-ready size in 18 months today vs 5 years a couple of generations ago. That time difference makes feedlot operations a methane mitigation winner—if eating such meat is a diet that must be preserved while trying to preserve the planet as a habitable place for humanity.

    In terms of thinking about what makes rational sense in sorting out that question, once you eliminate the feedlot’s ‘ivory tower’ control for pasture, latitude, soil, and weather variables, any resulting report can have enough “it depends” that the writing itself needs “Depends.” Anyway, the point you make has a salt-of-the-earth integrity I respect. If we are serious about controlling anthropogenic methane, ruminant animals husbandry has to go; as does your employment.

    The fun of cow pie fights may be lost on academics, and is generally limited to a child-like male sense of humor and delight. With the elimination of cowboys, it may become a lost art-form within the parameters of the entertainment industry. Virtual dry turds just don’t pack the same emotional punch as the real thing.

    That aside, if they didn’t get tossed around, they could be studied. I bet such studies would show that they, like pot hole wetlands in the plains, are micro environments for earth building microbes and bugs, that, in terms of sequestering carbon, dung pies play as vital a systemic role. And, particularly given the life times of the greenhouse gases of CH4 and CO2, may more than compensate for the methane produced. Regardless, the annual rainfall will be a variable that will have simple minded thinkers calling for diapers when trying to make sense of any report. Conversely, If one grew up in a hut plastered with dung straw, and urine, one would know that once dry, it sheds water quite well. Add this to the point that additional methane production from dung remains stable becasue the conditions for anaerobic decomposition ends with the initial drying (and the death of the related microbes excreted with the manure).

    BTW, can you venture a hayseed assessment of my comment #155 about Arctic atmospheric methane? If the methane time bomb has been detonated, such makes this conversation about ruminants and methane mitigation, rather academic . . . kind of like the argument that geopolitically jurisdictional limits, cap & trade ‘controls’, and offsets are a scientifically relevant approach to mitigating fossil carbon generation!

  163. Paddy:

    159, I’ll stick by my guns- high quality food produces less CH4.
    I think you will find that feedlots are situated close to feed sources, even with energy prices as cheap as they are transportation is costly.

    Hank, some numbers: livestock- 2.2 billion tonnes CO2e
    Fossil fuel CO2- 28.4 billion tonnes CO2

    New carbon to biosphere each year- Livestock Nil*
    fossil fuels- 8 billion tonnes(my back of envelope figuring)

    *Accordingly agriculture as a whole is said to be responsible for consuming 1.5% of fossil fuel derived energy, and obviously livestock production does use a fraction of that.

  164. Hank Roberts:
    Each green circle is a large feedlot.
    There are other feedlot problems turning up:
    which are going to be of interest to the researchers working on long distance dust movement generally

  165. dhogaza:

    I think you will find that feedlots are situated close to feed sources, even with energy prices as cheap as they are transportation is costly.

    On the other hand, many of the cow-calf operations that provide the steers are often in the semi-arid west, places like se oregon, nevada, new mexico, etc. They haven’t walked to the feedlots since before clint eastwood starred in “Rawhide” …

  166. nathan currier:

    Since you’re on the topic of the indirect aspects of the methane GWP, could you explain how to calculate in the FF (feedback factor).

    I’m trying and can’t figure out how to add it in.

    Without indirect effects, I get the CH4 GWPs – 49.54 ;17.75; 5.43 (20,100,500 yr horizons respectively)

    When I add the O3 & H2O indirect effects according to AR4 updated figures
    (25% + 15%), then I get GWPs of – 69.35;24.85;7.61.

    I’m assuming my 20 and 100 year horizons still don’t quite match the updated IPCC ones because the FF isn’t in there. Is that right?

    Could you show me how to calculate that myself? I’ve read discussions on
    what is behind it, the adjustment time changes, etc., but that doesn’t help me to calculate myself…..

    Thanks SO MUCH!!!

  167. Greg Robie:

    Hello Gun Totten Paddy,

    Having read Chapter 5, it looks to me like it is saying that all that is needed to bring the CH4 production of a low protein diet ruminates in line with feedlot cousins is to add a bit of a molasses-urine milkshake to the diet. What I do not see in that chapter is a comparison of CH4 production of feed lots and well managed pasture. Perhaps all this thread has identified is more of the “it depends” variables about which too little is know and requires positions to be defended with fire-power rather than fact-power.

    BTW, what is your take on the thoughts about Arctic methane as per comment #155?

  168. Paddy:

    164, Hank I think you’ll find plenty of worries about environmental estrogen levels originating from human sewerage.

    Seen an aerial view of a city waste water plant let alone the concrete monstrosity that is the modern city? makes a feedlot look teensy weensy. The green dots can be a bit misleading, there are 45 million acres in Nebraska, and at normal feedlot densities 20000 acres would be cattle pens. 0.0005%.

    165, So it’s cheaper to use unsustainable fossil fuels to transport cattle by truck rather than walking? There’s a surprise. Walked to work lately? The average American commute is 16 miles.

    167, I’ll go back through chapter 5 when I get a chance. There’s no doubt that the variables are diverse, and depends too on how we choose to measure impact- emissions per head, per kilo gain etc. Even between grass species methane produced can vary up to 50% per head.

    Re.155, it’s a wee bit longer than my attention span but here goes:
    Addressing Arctic methane, theres anticipation than extra temperature will release methane from melting permafrost and lakes. I too have read about the levels being well above background, but I don’t know if this is a recent comparison or if levels would have been similarly elevated pre-fossil fuels. My understanding is methane releases from permafrost will be limited through microbial conversion. Lakes I’m not so familiar with. The amounts of methane stored are staggering.

    My parting thoughts on livestock methane:
    We could well eradicate ruminants and get a one off fall in methane levels, lets say for convienience take 20% off 1750ppb to be 1400ppb(simplistically livestock contibute 40% of total humane methane emissions, which is roughly the same as natural methane emissions.thus 20% of all methane emissions).

    A one off 350 ppb fall in CH4 compared to an annual gain of 2000ppb of CO2. Probably looks alright on paper using 23x warming potential, but factor in the weight difference per molcule of CH4(approx 1/3 of CO2) and we’ll find that one years CO2 production from fossil fuel burning eliminates all the gain of such an action.

    some assumptions I’ve made-
    3000 Gt of CO2 in atmosphere
    28 Gt of Antropogenic CO2 emissions annually
    CO2 380,000ppb
    CH4 1,750ppb for ease of calculation
    CO2 molecule 2.75 times heavier than CH4 molecule
    GWP of gases compared by weight

  169. Greg Robie:

    Paddu, thanks for your thoughts regarding the increase in Arctic CH4. Since you frame your reply around such as an _anticipated_ increase, I guess I was not clear. I observe that the ‘anticipated’ increase is a present reality—but for enough knowledge and data to see this; but for a focus on CO2. The amounts of CH4 in the Arctic are staggering. And the ship-based 2008 measurements in the Arctic Ocean over the continental shelf turned up up-to-100X higher levels of CH4 over previous background measurement data (clathrates are another source of CH4 in the Arctic, besides soils and lakes—both microbe-driven sources).

  170. sciencebod:


    I’m new here. I do an Energy Blog for the Daily Telegraph, and am seeking an urgent answer to a question that’s been bugging me and others. Can anyone help?

    It’s to do with the mechanism by which infrared-irradiated CO2 gas dissipates energy. Is it by re-emitting a quantum of ir light? Or do the energised molecules, with their enhanced bond-bending vibration collide with other molecules, including non-greenhouse gases – giving them extra kinetic energy.In other words, bending vibration to translational motion. In the latter case, the resulting rise in temperature would presumably be radiated as a continuous spectrum from a blackbody.

    I’m still encountering people who say that there is no real physics to support the notion of a greenhouse gas radiating energy back to Earth, and I have to say I’m experiencing great difficulty in tracking down any references despite an hour or more of googling. It does seem to be a defect of the theory if the mechanism as to how ir is radiated back to Earth is not common knowledge and/or shrouded in mystery.

  171. David B. Benson:

    sciencebod (170) — It is actually not so easy. In the links, BPL provides some (approximate) equations:

    A different approach may be found in Ray Pierrehumbert’s

    If that is not enough then I fear you may need a graduate text on atmospheric physics, not something I care to tackle…

  172. sciencebod:

    That’s fine to be getting on with, David. Thanks a lot. I’ll get back once I’ve seen what those sites have to offer.

    Just a brief thought. Could one not go out after sunset, with no moon, and monitor back-reflected infrared. If it matches the discrete lines in the emission spectra of greenhouse gases then it’s a photon in-photon out mechanism. But if it’s a continuous spectrum, as if from a blackbody, then it’s a photon in, no immediate photon out. The incoming photon has briefly energised the greenhouse gas molecule, which has then shed the energy through kinetics, ie imparting translational kinetic energy to its neighbours, which then radiate a bit more as a blackbody. So there is a photon out, finally, but not from the originally energised trapping molecule, or even from a greenhouse gas (predominating O2 and N2 would serve for the purpose of dissipating the excited bond enrgy. I hope that makes sense.

  173. paddy:

    grog, 100x can be somewhat misleading, if you measure near a methane plume then yes it is likely to have a higher conc than background.
    The same study indicates surface methane at 3 to 4 times background, which is alarming to a degree but we have to accept that some areas emit and some don’t. Those that emit would presumably have a higher local conc.
    The gist of my point is that I haven’t found what the continental emissions are now compared with 20 or so years ago, and whether or not they are orders of magnitude different. Some direction would be welcome.

  174. Hank Roberts:

    More data on animal waste/manure quantities:

  175. Hank Roberts:

    > monitor back-reflected infrared. If it matches the
    > discrete lines in the emission spectra of greenhouse
    > gases then it’s a photon in-photon out mechanism. But
    > if it’s a continuous spectrum, as if from a blackbody,
    > then it’s a photon in, no immediate photon out.

    Remember the infrared going out from the ground is already very broad. Most of it gets captured, except for a few narrow ‘windows’ — so you’re not looking for what you think, I think.

    I think there will still be emissions characteristic of the various bonds in the molecules — that’s one way gases are identified, by their emission spectrum fingerprints. Someone who knows something can certainly comment on that.

    But if we got only exact lines, the infrared astronomers would not have to make so much of an effort to subtract the atmospheric background, as by tipping and tilting telescopes to subtract the atmospheric emission; they could just filter the narrow spike frequencies.

  176. sciencebod:

    Thanks Hank

    Yes, the outgoing ir radiation is ‘broadband’, so to speak (is one allowed to say that without causing confusion)? But it’s possible to imagine that an ir spectrometer pointed up at the sky after sunset might pick up nothing but discrete lines were all the back-radiation due to absorption and re-emission at those fixed ir frequencies that correspond with specific modes of bond excitation. Alternatively, back radiation could also be broadband if the bond-exciation were quickly dissipated to neighbouring molecules via collisions, the latter acquiring greater speed, and becoming better blackbody broadband radiators.

    Yes, the difficulty is that there will always be a warm blanket of gas with broadband radiation coming back to Earth. But the key question is whether there is additional energy at discrete frequencies, and measuring the amountproportion of energy coming back in discrete frequencies. What would it be as a percentage of the flux of blackbody ir radiated from the planet’s surface?

    A lot of sites and papers seem to imply that discrete frequencies are simply pinged back to Earth, but I doubt very much that is the case. It’s probably mainly “broadband” due to kinetics and momentum-transfer, but I wish I had hard evidence on that.

    Thanks again. Further comments welcome.

  177. Jamie Lloyd:

    After reading most of these blogs, I have a Question: How do we rationalize the two sets of data below in a way that makes sense to average people? Al Gore just putting the new Shindell et al numbers out there without cogent explanation really confuses people and undermines support at a pretty crucial time, politically.

    Please help.

    IPCC (2007 Synthesis Report) says:
    Global Anthropogenic Greenhouse Gas Emissions in 2004
    CO2 (total:fossil, cement, deforest) = 76.7%
    CH4 = 14.3%
    N2O =7.9%
    F-Gases = 1.1%

    Al Gore’s new book says:
    Six Types of Global Warming Pollution
    CO2 = 43.1%
    CH4 = 26.7%
    Black Carbon = 11.9%
    Halocarbons = 7.8%
    CO + Other Organic Compounds = 6.7%
    N2O = 3.8%

    [Response: The principle difference is whether you attribute the forcing by what we emit or by what is in the atmosphere. They differ because of the indirect effects (mainly due to methane) on atmospheric chemistry. Our previous post on methane has some links and background. Also check out figure 2.21 in AR4. – gavin]

  178. Completely Fed Up:

    If 100% of IR at CO2/H2O/etc bands are absorbed, then the emission spectra of the earth would be broadband at ~220K (or whatever) with ABSOLUTE BLACK at those absorption bands.

    If this isn’t true then it can’t be 100% absorbed, can it? Since only with less than 100% absorption can any of that absorbed light be visible from space.

    If you maintain 100% absorption therefore no effect from more CO2 yet also agree with the evidence that these absorption lines are not black when earth is viewed from space, please explain the physics.

  179. Hank Roberts:

    > imagine that an ir spectrometer pointed up at the sky after sunset might pick up …discrete lines

    You’re pointing out that the words used in verbal explanations often aren’t clear, I think. Yep.
    And the infrared astronomers do look up, and do not see discrete lines (else they could filter them out and work from the grouhnd). So you do have your experimental proof, if that’ll do.

    This has been gone over at RC in several earlier topics. It took not just math but serious work with big computers to figure it (per Spencer Weart’s book); for the rest of us words like “mean free path” and “relaxation time” and “time between collisions” and altitude and density are just poetry.

  180. sciencebod:

    I think we’re on the same wavelength, Hank (no pun intended). If I read you correctly – let me know if that’s not the case – then the back-radiated ir is broadband – it’s been monitored and there’s no evidence of discrete wavelenghts. Therefore its wrong to imagine that CO2 moleclules etc act as a miniature trampolines for receiving and bouncing off ir photons, where a photon is briefly absorbed and immediately re-emitted at the same or similar discrete wavelength, which finally returns to Earth, still as discrete wavelngths. If by “poetry” your mean that the literature you read is full of terms like mean free path etc, then you do seem to be suggesting that it’s a chain of events that returns ir to earth as broadband radiation. In other words: CO2 molecules absorbs ir photon, becomes energised eg bond-bending oscillation, the oscillation energy is then passed on to another molecule, not necessarily greenhouse gas – through random collision and becomes, say, translational energy by transfer of momentum (note the original CO2 has retained its ir photon – it has not re-emitted). The “lost” photon finally reappears as part of the broadband spectrum of a slightly warmed troposphere that has captured and dissipated the energy of ir radiated from Earth. In other words, narrow band ir out, broadband back. Sorry if I’m stating the obvious, but it’s been difficult to get a clear statement of step-by-step sequences of events, yet one still gets sniped at whether one says it’s a simple ping-back mechanism or the opposite where the specific ir frequencies are lost, and the troposphere just becomes a warmer blackbody radiator.

    Completely Fed Up – thanks for the interest. We may or may not be talking about the same thing. It always takes me a while to get on to the same wavelength with a fresh contact. Would you agree or disagree with the mechanism set out here?

  181. sciencebod:

    Oops.I made a silly slip in that last comment. I said “narrow band ir out”. That should have been broadband out, needless to say, with selective removal of discrete wavelengths on first encounter with CO2 etc. Sorry about that. It’s late where I am.

  182. Syafrin:

    I am just an ordinary guy with no atmospheric science knowledge, I have a question bugging me long enough. Can anybody please help answer this question:
    Given all the present day figures and parameters of the global warming science, including the delay of terrestrial and ocean heat process, how much time we have before the arctic completely melts away and the peatbogs give out all the methane? I am aware of Wieslaw Maslowski’s prediction as well as Jay Zwally. Will the Arctic methane in the atmosphere suffice in invoking the methane clathrate out of the continental shelves?

    Two days ago I stumbled on a calculation which I can’t understand at:


  183. Completely Fed Up:

    sciencebod: “through random collision and becomes,”

    INELASTIC collision.

    That is the extremely important point that EVERY SINGLE DENIER ignores.

    Rather like they ignore the second law of thermodynamics says NET energy flows from hotter to cooler bodies. Forgetting “NET” and just coming to the assinine conclusion that a cooler atmosphere cannot warm the warmer ground. Assinine because NET flows are away from the warmer earth, but that is less than the NET flow if there were no atmosphere. The difference being the flow of energy from the cool ***but not absolutely cold (Zero Kelvin)*** atmosphere to the ground. For denialists, it’s as if there can be NO RADIATION OF WARMTH from a layer that is cooler than an adjacent one.

    “In other words, narrow band ir out, broadband back”.

    You’re looking for the term “thermalisation”. With enough collisions and transformations, all that energy is turned into a thermal broadband emission.

    Remember: there is no such thing as narrow band ir, just a narrow range of IR photons in the system. If those photons are destroyed by absorption, they don’t exist any more. How that energy is expressed depends on the system they are in, not the original source.

    And in the case of the optically thick atmosphere (in wavelengths it IS optically thick), the body they are in is a thermal source and will radiate as such with black-body intensities.

  184. paddy:

    thanks hank, I too always go to a pro-vegetarian site when I want objective information on animal production.

    Relating chicken production to a methane post is a bit off track though, chickens have one of the most efficient food conversion ratios of any land animal and aren’t enteric fermentors.

  185. sciencebod:

    Hello CFU

    It’ll take me a while to get my mind round all the subtleties there. One thing on which I think we’re both agreed is that the Second Law is only about initial and final states, and does not attempt to prohibit radiation exchanges that are from cooler to warmer bodies. A radiating mass of greenhouse gas will send out energy in all directions – some into space, some back to Earth. It has no way of knowing what is hotter or cooler – and doesn’t care anyway.

    The only difference that I can see in having a blanket of greenhouse gas is that it creates higher steady state temperatures on Earth than would otherwise be the case, with an intermediate temperature in the blanket.

    But some people are not happy with an argument that says Earth would be cooler but for the blanket – despite their guru acknowledging as much on p.366 of the Holy Writ. One cannot take the blanket away to give them proof. Thus my interest in knowing if it were possible to provide more direct evidence of back-radiation of infrared. If it were “broadband” then that would would prove nothing. But if it were narrowband, ie with frequencies corresponding to the known emission spectra of greenhouse gas molecules, then it would be exceedingly hard for them to deny the greenhouse gas effect would it not?

    One would presumably have to do the demo at night. During the day, the same greenhouse ags molecules would be absorbing photons from the sun’s ir radiation, creating an absorption spectrum, with “gaps” at the critical frequencies that would make it harder to distinguish emission from the atmosphere at those same frequencies.

    Thanks again for the interest.

  186. Pete:

    Hi, Gavin. Could you comment further on this exchange from an older post? Why is it much better to burn methane than to release it? Thanks!

    >>Question: Up here in Alaska our own Katey Walter is talking about the tundra methane releases as a source of energy for nearby communities. Understanding that nobody is going to build giant capture devices, still I would think burning methane would result in less damaging gases. Any calculations on that?

    [Response: Definitely. Methane is much better off burnt than released. (say hi to Katey if you see her). – gavin]<<

    [Response: Because molecule per molecule CH4 is a much more powerful GHG than CO2. So if you burn the gas, CH4+2O2 => CO2 +2H2O you reduce the forcing (and hopefully you get to use the energy released for something useful). – gavin]

  187. Pete:

    Much appreciated.

    Does the time frame matter though? I understand the higher short-term forcing, but on a century or longer scale would the additional CO2 eventually catch up in terms of its impact because of its longer residency in the atmosphere? Does the GWP of 33 for methane over 100 years make this a simple answer of “no.” Also, any idea on how completely methane combusts? Would there still be a fair amount of methane released even if you burnt it?

    If you use the combustion for energy than it makes this a moot point, but I’m curious about the comparison if you don’t.

    Thanks, and thank you very much for the resource you guys provide.

  188. Completely Fed Up:

    sciencebod: ” Thus my interest in knowing if it were possible to provide more direct evidence of back-radiation of infrared.”

    There are pictures of the brightness of the earth from space that shows at absorption bands for CO2, the earth is getting dimmer.

    If that’s not enough, then until we genetically engineer humans to see photons in transit ***in the transverse direction of travel*** and ***individually*** and also to get them to look (which for most denialists will be harder than the genetic engineering), there’s no way.

    Just like you can’t prove to the extremely devout that there is no God.

  189. JBL:

    Pete: if methane gets into the atmosphere, at some point it breaks down into CO2, so you get the effect from the methane followed by the (longer-term but less powerful) effect from CO2. If you burn the methane directly, you cut out the methane part of that deal completely and leave the CO2 part unchanged. Thus, it’s strictly better to burn the methane directly (even if for no useful purpose) than it is to release it into the air.

  190. Marcus:

    Pete (#187):
    1) The “GWP” is supposed to take into account time frame (well, at least for 100 years): using a GWP, methane is still 25 or so times as potent a GHG as CO2 (integrated radiative forcing).

    2) The other key point is that if you don’t burn methane at the release, it still eventually oxidizes to CO2 in the atmosphere (sometimes producing ozone and reducing hydroxyl radical along the way): so really what you’re doing by burning it is not “producing” CO2 but rather skipping the 10 year stage in which the methane hangs around as CH4 before turning into CO2 anyway.


  191. Pete:

    Thanks everyone (Gavin, JBL, and Marcus).