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Methane game upgrade

Filed under: — david @ 14 June 2012

Walter Anthony et al (2012) have made a major contribution to the picture of methane emissions from thawing Arctic regions. Not a game-changer exactly, but definitely a graphics upgrade, bringing the game to life in stunningly higher resolution (/joke).

Katey Walter Anthony draws upon her previous field findings that methane emissions from the Arctic landscape tend to be focused at the intersection between frozen and thawed, in particular in rings around a peripheries of lakes. She also knew what a methane seep looks like in that landscape, leaving visible bubbles frozen into the ice or maintaining an unfrozen hole in the ice. Now she takes to the skies to produce an aerial survey of the Alaskan landscape, data that is so much more voluminous than before that it becomes different in kind.

The methane emission fluxes are higher than previous estimates, but that’s not really the most important point, because emissions from the Arctic are small relative to low-latitude wetlands, and doubling or even nearly quadrupling the Arctic fluxes (in one of their analyzed regions), they would still be small in terms of global climate forcing. And the lifetime of methane in the atmosphere is short, about 10 years, so methane doesn’t build up like CO2, SF6, and to a lesser extent N2O do.

The really interesting take-away from the new paper is how it shows that the near-surface geology and freezing state conspire to control the venting of accumulated gas dribbling up from below, and the decompostion of frozen soil carbon. They have so many methane seep observations that they are able to correlate them with (1) currently thawing permafrost, which allows fossil soil carbon deposits from the last ice age called Yedoma to decompose (Zimov et al 2006) and (2) melting ice sheets and glaciers “un-crunching” the landscape as they fade away, making cracks that vent methane from deep thermal sources. Glaciers that melted long ago no longer vent methane, showing that the methane is transiently venting from built-up pools of gas.

What these results do not do is fundamentally change the game, in my opinion. We can now see more clearly that most of the methane flux from the Arctic today are of types of emission that will respond to climate warming. But the general response time of the system is slow, decades to centuries, rather than potentially poised to release a huge pulse of methane within a few years. Earthquakes and submarine landslides are sudden events, but small individually in terms of potential methane release. The new data do not change that. Walter Anthony et al. compare an estimate the amount of methane in the Arctic, 1200 Gton C, with the 5 Gton C of methane in the atmosphere. That’s the nightmare comparison, but it’s only really relevant if the methane comes out all at once. (The Arctic estimate is for methane itself and is mostly methane hydrate, but keep in mind that there is also a comparable amount of decomposable soil carbon.)

In my opinion, the largest impact of all this methane will probably be to the long-term future evolution of climate. Avoiding a peak warming of 2 degrees C or more requires keeping the total emission of carbon down to less than about 1000 Gton C (Allen et al 2009). We have already burned about 300 Gton C, and cut about 200 Gton C. So maybe we’re 1/2 of the way there, say 500 Gton C left to go. The 1200 Gton C of Arctic methane hydrates and the permafrost carbon stack up pretty menacingly against our 500 Gton left to go, and the comparison is relevant even if the carbon is emitted slowly, or as CO2 rather than methane, or even if it is released into the ocean rather than into the air (it will still equilibrate with the atmosphere, after a few centuries, converging to the same “long tail” CO2 trajectory that would have resulted from atmospheric release).

Arctic methane, and all that frozen soil carbon, could easily play a huge role, not so much in the near-term evolution of Earth’s climate, but in the long tail of the global warming climate event.

Allen M.R., D.J. Frame, C. Huntingford, C.D. Jones, J.A. Lowe, M. Meinshausen & N. Meinshausen (2009) Warming caused by cumulative carbon emissions towards the trillionths tonne. Nature 458 doi:10.1038/nature08019

Shuur E. et al (2008) Vulnerability of Permafrost Carbon to Climate Change: Implications for the Global Carbon Cycle. BioScience, 58(8):701-714.

Walter Anthony, K.M., P. Anthony, G. Grosse, & J. Chanton (2012) Geologic methane seeps along boundaries of Arctic permafrost thaw and melting glaciers. Nature Geoscience doi:10.1038/NGEO1480

Zimov, S.A., Schuur, E.A.G, and F. Stuart Chapin III, F. (2006) Permafrost and the Global
Carbon Budget. Science 312: 1612-1613.


177 Responses to “Methane game upgrade”

  1. 51
    Killian says:

    I can’t help but want to put more emphasis on what we are actually seeing in the Arctic than what didn’t happen in the past. David, your posts on this have thankfully become closer to what the observations say, but you continue to simply discount the possibility of abrupt emissions from the Arctic despite the work of the last couple years indicating that, indeed, abrupt changes seem to already be happening.

    The Arctic Ocean, itself, seems to be a bigger emitter than previously thought… or even known. Kilometer-wide seeps were found this past summer/fall while only meters-wide seeps had been found previously. Walter-Anthony stated several years ago thermokarst lakes had tripled in well under a decade.

    Those changes are hyperbolic curves and it has been stated a mere 1 to 2 percent of the Arctic stores being emitted might be enough to push us into a state we cannot reverse.

    Models are great, but they have consistently underestimated change overall. We are, after all, tracking the high ends of the model runs, are we not? I’d like to see a completely balanced post from you on this. IMO, your scientific reticence is causing you to favor the models and history over current events that are ominous. This is common, of course, as the Arctic has been outdoing the models, the majority of runs anyway, all along.

    The planet has never been in this situation. It has never been this generally degraded and changing at this speed from other than extraterrestrial forcings, right? Personally, I don’t think we have a corollary to draw on, and given the rates of change, should look at paleoclimate as more of a low end of worse case rather than a high end. That Arctic abrupt, large releases may not have happened much before happened much before is zero comfort to me. Logically, it’s a dangerous position. It’s the type of logical fallacy that gets one beaten in a debate.

    The direct observations say the Arctic is changing rapidly. Methane content is spiking per a recent paper.

    http://www.atmos-chem-phys.net/12/4885/2012/acp-12-4885-2012.html

    Again, I’d like to see a less reticent and sanguine post on this that more directly addresses what the issues raised here mean.

    * 3x increase in thermokarst lakes 2000 (or so) to 2007
    * Arctic sea bed seeps a kilometer wide
    * methane directly from the Arctic Ocean
    * the general degradation of the planet

    And, finally, in my own bailiwick, they are finding, pretty much across the board, that the Earth and its biota are more sensitive to temp changes than thought. As a permaculturist, trained to see the whole system fully interconnected, I think, “Well, duh!” I’d like to understand better why your response is more along the line of, “Well, hold on a minute; it’s not as bad as all that.” Basically, while I have noted your posts on this issue seeming to acknowledge more of the potential severity of the situation over time, I still don’t see the science of the last year fully reflected in them.

    reCAPTCHA mocking me? “urreOs impertinent.”

    Cheers

  2. 52
    D Coyne says:

    Chris Colose provided a link to a paper by the national academies which reviews several papers which link cumulative carbon emissions to warming.
    My reading of that paper is that the carbon emissions due to land use change are added to other carbon emissions from fossil fuel, cement production and natural gas flaring, the uptake of carbon by the biosphere is included in the models and is not to be subtracted from emissions. The different studies come up with different estimates of cumulative carbon that will result in two degrees celcius of warming above 1850-1900 levels. Their median estimate is 1150 billion tons of carbon (GtC) with a very wide window of 800 to 1600 GtC to keep warming close to 2 C.

    DC

  3. 53
    Geoff Beacon says:

    I didn’t quite follow all of David’s comments to my #30 and remain to be convinced that the Allen et. al. Trillion tonne is not flawed by missing feedbacks. Another, perhaps illogical, reason I am unsettled comes from Myles Allen’s comment on the Arctic sea-ice. From my BrusselsBlog:

    In 2007, the summer extent of Arctic sea ice reached its lowest since satellite records began, significantly lower than previous years. Some interpreted this loss as a significant change in the speed with which sea ice is being lost. Senior Scientist Mark Serreze at the The Snow and Ice Data Centre said at the time, “The sea ice cover is in a downward spiral and may have passed the point of no return. As the years go by, we are losing more and more ice in summer, and growing back less and less ice in winter. We may well see an ice-free Arctic Ocean in summer within our lifetimes.”

    In the subsequent years, 2008 and 2009, the summer extent of the sea ice was higher than the 2007 minimum. This led some scientists to criticise exaggerated claims. A Times piece quoted Vicky Pope, head of climate change advice at the Met Office as saying

    “It isn’t helpful to anybody to exaggerate the situation. It’s scary enough as it is. The problem with saying that we’ve reached a tipping point is that when the extent starts to increase again — as it has — the sceptics will come along and say, ‘Well, it’s stopped’.”

    Professor Myles Allen, head of the Climate Dynamics Group at Oxford, was also quoted: “Some claims that were made about the ice anomaly were misleading. A lot of people said this is the beginning of the end of Arctic ice, and of course it recovered the following year and everybody looked a bit silly.”

    How fast is Arctic sea ice disappearing?

    My judgement is that Myles got it wrong then. Should I let this cloud my thinking?

  4. 54
    Ray Ladbury says:

    Killian,
    We face a lot of threats. There are a lot of things that could send us over the cliff. The past is important because it tells us which threats are credible. The fact that we have reached temperatures higher in the past without seeing catastrophic releases tells us we should be OK until we reach those same worst-case conditions again–in a few decades.

    If we pay attention to what is going on in the Arctic at present, it doesn’t come close to catastrophic release unless we extrapolate to an extreme amount.

  5. 55
    dbostrom says:

    Killian: I’d like to see a completely balanced post from you on this. IMO, your scientific reticence is causing you to favor the models and history over current events that are ominous.

    Once we loose speculation where should it stop?

    Speculation is amply staffed, the hard work of explanation not so much.

  6. 56
    wili says:

    Geoff, yes, the myfootprint site is flawed, but I haven’t found anything better yet. But it helps to show people that, while you have to give up some things, you don’t have to live a completely ascetic life to live sustainably. (Perhaps I just like the site because they don’t say I have to give up beer ‘-)

    Ultimately, any project to reduce something as complex as our relationship to the earth down to a number is going to be simplistic and reductionist, of course.

    I may be interested in helping with your site, as I am in ‘transition’ in my current career. Do you want to get in touch?

    I also agree that most of the stuff out in the media is…well, your term ‘greenwash’ is kind. Consuming (even ‘green consuming’) to save the planet is like fighting for non-violence, or something-else-ing for celibacy.

    I’m with Killian (except for a minor quibble that the new plumes found by Semiletov and co. were about one k across, not many k, thank Goddess). The past is a guide for setting a baseline expectation for future events, but not so much to tell us what the worst case consequences of our current actions might be, since we have pushed systems beyond tipping points so much faster than anything we can find in the past and on so many fronts.

    (I’ve been hoping for a different kind of tipping point–one in general human consciousness about our place on the planet–for decades now, but we seem further from such a realization than ever.)

    The two most relevant questions seem to be:

    1. What are the possibilities for sudden catastrophic release of game-changing quantities of methane from Arctic sources? (Shakhova has said 50 billion tons could be suddenly released at any time, iirc. Many here seem to disagree. Seems reasonable to me to say that we cannot be 100% certain it can’t happen.)

    [Response:I'm skeptical it could happen but even if it did, what it would do would be to give us a preview of what 2100 will be like under business-as-usual. One that would immediately begin to subside, instead of inexorably worsening and lasting forever like the CO2 impact by 2100. Might lead to the human awareness tipping point you're looking for. I'm much more frightened of CO2 than I am of methane. David]

    2. Are we seeing what is likely to be the beginning of an exponential increase in methane release from Arctic sources, and if so, what kind of potential exponential curves might we be looking at?

    To John E. Pearson at #50 who said, “Burying CO2 strikes me as quite sane.”

    I would agree if you mean replanting the native prairie so it’s long roots can sequester CO2 or other such projects. I have done a good bit of that myself. I was mostly speaking against intentionally spewing additional vast quantities of aerosols into the upper atmosphere for ever, other such high-tech ‘fixes.’

    But, as Hank has pointed out (in his own way), the main thing we have to do as fast as possible is to stop UN-sequestering carbon at the furious rate of ten-some billion tons a year, along with halting or greatly curtailing other practices–forest clearing, most cattle raising…–that further exacerbate the situation.

    And, imho, we should stop doing that even if we heard that it is a total certainty that we are about to have a multi-billion ton emission of methane from the Arctic or elsewhere. The consequences of previous abuse should never be used as an excuse for further abuse.

  7. 57
    Ray Ladbury says:

    wili, “Could be” does not make for a credible threat. What is more, it is unclear to me how we would attempt to mitigate this threat other than what we should be doing to avoid catastrophe resulting from CO2, since methane release is thermally activated.

    It is clear that we can anticipate some substantial carbon release from melting permafrost, etc. in the not to distant future. There is no firm evidence that release will be catastrophic–at least not until temperatures are 2-3 degrees higher than they are now. At that point we will have lots of other wories as well. Let’s not abandom proper risk mitigation out of alarm.

  8. 58
    Steve Fish says:

    Re- Comment by wili — 18 Jun 2012 @ 6:05 PM:

    If your admonition to curtail cattle raising refers to reducing the use of fossil carbon for the production and distribution of meat, egg and milk products, then I agree. However, this being a methane thread, if you think that the methane produced by farm animals is significant then I think you are mistaken. Steve

    (noble tepowit)

  9. 59
    wili says:

    To add insult to global injury, we are subsidizing the UN-sequestration of carbon at record high rates:

    “Why $775 billion in fossil-fuel subsidies are so hard to scrap”

    http://www.washingtonpost.com/blogs/ezra-klein/post/why-775-billion-in-fossil-fuel-subsidies-are-hard-to-scrap/2012/06/18/gJQABaQUlV_blog.html

    “The idea of repeal first came up in 2009, when leaders at the G-20 summit pledged to phase out fossil fuel subsidies over the next decade. Since then, an additional 50 countries have said they’d do likewise. Yet those promises have had virtually no effect. As a new report (pdf) from the Natural Resources Defense Council details, global subsidies have nearly tripled since 2009 — from $300 billion to $775 billion.”

    Subsidies for UN-sequestering safely buried carbon have TRIPLED just since 2009.

    What are we?

  10. 60
    Jim Larsen says:

    54 Ray L said, “The fact that we have reached temperatures higher in the past without seeing catastrophic releases tells us we should be OK until we reach those same worst-case conditions again–in a few decades.”

    Previous warmings were much slower, which makes the comparison potentially flawed. For example, “normally” sea level rises as temperatures increase. This tends to stabilize clathrates as higher pressure offsets temperature increases. Today, sea level rise lags far behind temperature increases, so clathrates will be more likely to disassociate. Similarly, ecosystems “normally” have time to adapt to rising temperatures. Not this time, though. It’s easy to visualize massive beetle-caused tree death and the resulting mega-fires leaving vast swaths of blackened landscape sucking up solar energy and causing the release of tremendous volumes of CH4.

    [Response:Well, just to play devil's advocate, there were abrupt climate changes in the past called Dansgaard-Oeschger events, that were very fast, climate flip-flops in just a few years recorded in Greenland ice cores. Another devil's stick in the spokes would be that diffusion of heat into a solid body like permafrost soils is slow, so they wouldn't probably respond much more strongly to a fast change in temperature. It would respond to the longevity of the forcing more than to the quickness off the mark. David ]

  11. 61
    Ray Ladbury says:

    Jim Larsen,
    At the same time, oceans had more time to come to equilibrium (higher temperature) which would destabilize the clathrates. I just don’t see the evidence that we are near a catastrophic release.

    I think people hear about km-wide regions bubbling and don’t realize that for for the types of catastrophic release people are talking, the regions involved would be a thousand times bigger.

    “It’s easy to visualize…” and “This is different…” also do not establish a credible threat.

  12. 62
    Geoff Beacon says:

    Steve Fish #58

    However, this being a methane thread, if you think that the methane produced by farm animals is significant then I think you are mistaken. Steve

    Any references?

    There are some on http://nobeef.org.uk

    The references give a different story to yours. One says livestock is 51% of GHG … mostly because of methane.

    (I’ll be in tough wili)

  13. 63
    Geoff Beacon says:

    Wili
    - that should have been “I’ll be in touch.”

  14. 64
    Steve Fish says:

    Re- Comment by Jim Larsen — 18 Jun 2012 @ 11:33 PM:

    You are making some rather extravagant claims without any of the extravagant evidence required to support them. Please provide some citations of research that predicts an eminent world wide catastrophe. A review article in a respected journal by someone of the caliber of, for example, David Archer would be very helpful. Steve

  15. 65
    Steve Fish says:

    Re- Comment by Geoff Beacon — 19 Jun 2012 @ 8:37 AM:

    Nobeef.org is not a scientific journal and there is very little reliable scientific information there, just references to popular culture articles.

    I think that Nobeef, and other agenda driven organizations, deliberately misunderstand the carbon cycle. All of the methane produced in agriculture was CO2 that was taken out of the atmosphere by the plants that were grown to feed the critters that make the methane. This is pretty much zero sum in the large scheme of things

    In addition, this is an ongoing process with the methane degrading to CO2, in ten years or so, so it can be used again to make plants. The methane doesn’t increase the greenhouse effect over time except to the extent that production is increased.

    Just about everything that grows eventually breaks down and releases CO2, and agriculture for human and animal food is only destructive to the extent that it releases carbon stored in the soil, or from fossil carbon. If you don’t believe this, then you should be railing against rice production, wetlands, and rampaging termites, all major methane releasers.

    Steve

    [Response:A lot of carbon comes out of the ground to do agriculture, too. Fuels, fertilizers, and what not. My recollection is that the overall process takes more carbon out of the ground as fossil fuels than out of the air by photosynthesis. By calories, it would be more efficient to eat fossil fuels directly. David]

  16. 66
    James Staples says:

    I’m less concerned with the Methane being released by the melting of the Arctic Permafrost, then I am with the decomposition of Deep Ocean Methane Hydrites that’s beginning to happen as Global Warmings warming penetrates deeper into the ocean.
    Also; as I wrote to you in an E-mail, after (somewhat belatedly) reading about the ‘see-saw’ effect that the Record Preserves regarding the uneven warming/melting (between the North and South Hemispheres) at the end of the last Ice Age; I’ve been wondering if the hindering, by Fresh Meltwater, of the AMOCs’ (sp?) ‘deep, cold, return flow’, and the subsequent warming of the Southern Ocean (especially at depth) wasn’t doing just that! – i.e.: Triggering the decomposition of Methane Hydrites in the Southern Ocean, and setting up a ‘Southern Hemisphere specific’ Methane Feedback Loop that would have, due to the Equatorial Bulge, accounted for more than a little of the observed ‘see-saw effect’.
    Whadaya Thunk?

  17. 67
    D Coyne says:

    Hi David,

    I appreciate that you took the time to respond to my comment (#49), I appreciate all you do here and only bothered you because I thought maybe I had misunderstood the Allen paper.

    D Coyne

  18. 68
    dbostrom says:

    Fossil fuel–>nitrogen fertilizer–>corn–>beef.

    Don’t feed cattle w/fossil fuel and we’ll do better.

    wili: Subsidies for UN-sequestering safely buried carbon have TRIPLED just since 2009.

    What are we?

    Homo Bolidus.

  19. 69
    Geoff Beacon says:

    Steve Fish #36

    Nobeef.org is not a scientific journal and there is very little reliable scientific information there, just references to popular culture articles.

    Here are links found from http://nobeef.org.uk

    http://onlinelibrary.wiley.com/doi/10.1111/j.1740-0929.2007.00457.x/abstract

    http://www.fao.org/docrep/010/a0701e/a0701e00.HTM

    http://www.cranfield.ac.uk/sas/naturalresources/research/projects/is0205.html
    http://www.foodbase.org.uk//admintools/reportdocuments/575-1-1008_X02001__Climate_Change_and_Food_Report__28_Sept_2010.pdf

    One peer reviewed paper, reports from the FAO, DEFRA and the Food Standards Agency. The reports have plenty of peer reviewed references.

    Can you show your references?

    What worries me about methane’s short stay in the atmosphere is that over 20 years it is 105 times the GWP of carbon dioxide. As I understand it is largest part of the 50% of climate forcing that isn’t carbon dioxide. (Water vapour excluded from that). Methane’s extra warming may bring tipping points from which our descendants cannot escape.

    So methane is the raw material for “plant food”.

    Have I heard that before?

  20. 70
    Jim Eager says:

    Geoff Beacon: “So methane is the raw material for “plant food”. Have I heard that before?”

    Wrong argument, Geoff. The better analogy would be the “are they going to tax breathing too” argument.

    Methane from ruminant digestion is analogous to CO2 from respiration, neither are net additions. I’ll grant you the difference that CH4 has a stronger effect at current concentration, but it wasn’t all that long ago that Africa and North America supported ruminant populatins comparable to current cattle herds. And as Steve pointed out, rice production gives beef herds a run for the title. Are you going to go after rice, too?

    I’m not arguing in support of over consumption of beef, just trying to place it in context with other methane sources.

  21. 71
    MARodger says:

    Geoff Bacon @69
    Yes. Methane is the second largest positive anthropogenic forcing as you suggest, but only just. Its ‘relative’ contribution has declined over the last decade as atmospheric methane levels have only risen 2% over that period.
    The top three positive anthropogenic forcing as of 2010 were CO2 (55% of total), methane (15%), troposheric ozone (13%).
    Link here (two clicks) to my take on anthropogenic forcing (after Skeie et al 2011)

  22. 72
    Killian says:

    We face a lot of threats. There are a lot of things that could send us over the cliff. The past is important because it tells us which threats are credible.

    The logic is wrong here: it’s a system in which the entire system is going out of balance, not part of it, thus the parts are not the problem, but interplay of them all. This is where the logic falls for almost everyone. For example, the people looking solely at climate do not consider the possible *collapse* in anthropogenic emissions should A. peak extraction have occurred or occur in the next couple decades. (Crude oil extraction has already peaked.) but then the Peak Oil folk fail to consider what gets burned if people don’t have access to oil. (The forests and anything else they can get their hands on.) This is but one example.

    So, fine, we are talking only about naturally emitted methane. Still, the interplay of the continuing rise in emissions directly affects the methane emitted. As more ice melts back (and we seem on track for the @2016 80% ice loss), more runoff occurs, more warm waters enter from the large oceans, etc., this is not going to reverse itself. And, yes, while ultra-short times scales are not confirmed in the paleoclimate record, there exists no corollary with today. There is no comfort in the paleoclimate record given there is no corollary. It hasn’t so it can’t? This is simply poor logic.

    The more appropriate question is, how quickly *can* emissions, particularly natural emissions forced by rising temps, rise vs. how quickly we can adapt? It is the rate of change, not the totality. On this Archer is incorrect, imo. My work involves creating anthropogenic change to our ecosystem to create sustainable communities. Rate of change is massively important in this work, and I am telling you changing the way 9 billion people live is not something that is done quickly outside of massive disruptions to the system. Here we have to understand it is the extremes we experience along that way that drive the greatest change, not the slope of the trend. As the extremes become larger and more frequent they will disrupt our human-built systems and the ecosystem, limiting the ecosystem services available. These changes *will* feed back to drive greater and faster change.

    “The fact that we have reached temperatures higher in the past without seeing catastrophic releases”

    Sorry, no corollary there. The deposits we are worried about have largely been laid down during the Ice Age era, correct? Only in this interglacial has mankind been around to muck up the entire ecosystem. This cannot be emphasized enough: the ecosystem is not going to respond as it has in the past because it has never been this degraded before the poop hit the fan, nor has it had to support 9 billion people.

    Also there was a recent paper on large methane emissions at one of the extinctions (sorry, lost all my bookmarks when my computer crashed in January). The rate was still long by human standards, but was short and abrupt by geological standards and was indicated as a causal of warming rather than in response to warming. That is, the bulk of the warming came after the methane release.

    tells us we should be OK until we reach those same worst-case conditions again–in a few decades.

    See my comment above about the rate of change of human systems to adapt. It takes 5 – 7 years for a single homestead to become self-reliant, e.g. And, it absolutely does not tell us that. That would only be true if there were a direct corollary. Not only is there no somewhat similar corollary, there is none at all. The oceans are already becoming saturated at the water/air boundary. Some studies indicate this will slow absorption and increase the rate of increase in the air. Also, while we keep being told that methane is no big deal right now, the fact is it has risen in the air at several times the rate of CO2. From 700 ppb to over 2000 in some areas at certain times now (see Spitsbergen record). While CO2 has gone up some 37% or so, methane has gone up 300%, and most of that was likely without the effects of ACC. With the clathrates clearly accelerating their break down, all bets are off, aren’t they? And, let us bear in mind the local effects of methane emissions prior to becoming well-mixed (which doesn’t ever really happen at the local point of emissions so long as they continue) are potentially important in scale.

    If we pay attention to what is going on in the Arctic at present, it doesn’t come close to catastrophic release unless we extrapolate to an extreme amount.

    And why wouldn’t we do that? While some have said clathrates release slowly, that is incorrect, so far as I know. They are actually quite binary: a given temp and pressure combination equals stable while a small change to above the given combination threshold equals instability. I must assume the claim they release only slowly comes from (in addition to the issue of the paloeclimatic record) considering the clathrates like a block of ice where only the outside perimeter melts. Sadly, we are talking about pools of gas/liquid methane, too. And, the hydrates are not in nice, neat solid blocks, but are uneven, scattered, lumpy, infiltrated. Expecting a steady rate of emissions is not likely to bear out, imo.

    Killian: I’d like to see a completely balanced post from you on this. IMO, your scientific reticence is causing you to favor the models and history over current events that are ominous.

    Once we loose speculation where should it stop?

    Speculation is amply staffed, the hard work of explanation not so much.

    Comment by dbostrom — 18 Jun 2012 @ 4:13 PM

    Do you consider looking at the science in context of the ecosystem speculation? How does that work, exactly? The rate at which clathrates and permafrost melt are directly related to what we do to the ecosystem, and not just in terms of emissions. The science of methane emissions is not just about flasks and poking holes in the ice and lighting the methane on fire, not just about looking at the paleoclimate. The issue is one and only one, if you wish to simplify: anthropogenic changes to the ecosystem. It is that rate of change that forces all others. If you attempt to separate the two, it will be impossible to understand the system you are attempting to understand.

    This is anything but speculation. Have you tried, for example, extrapolating out Walter-Anthony’s finding of a tripling in thermokarst lakes in less than seven years? I wonder how much stable permafrost we’ll have left if that rate continues. I’d like to know what the estimated area of thermokarst lakes is and do the math on that. Has anyone bothered?

    I understand the desire to keep to the science. What I am trying to say is, this *is* the science. The ecosystem. Tripling of thermokarst lakes and sea bed emissions sites of meters across to a kilometer or more. Ignore that science at your peril. Our peril, rather.

  23. 73
    Jim Larsen says:

    Ray L said, “At the same time, oceans had more time to come to equilibrium (higher temperature) which would destabilize the clathrates. I just don’t see the evidence that we are near a catastrophic release.”

    Neither do I, though Dr Shakhova’s 50 gt abrupt release scenario hasn’t been refuted yet. As has been pointed out, even that wouldn’t necessarily be “catastrophic”, as it only represents a couple years worth of carbon once it degrades.

    Past interglacials are good evidence, but they’re no guarantee. And, as you pointed out, that hypothetical guarantee is set to expire as we blow by previous interglacials.

    64 Steve F, what extravagant claims? I said, “Previous warmings were much slower, which makes the comparison potentially flawed.” I have no clue how you interpreted not “flawed” but “potentially flawed” as “[imminent] catastrophe”. If you’d quote something from my post with which you disagree, I’d be happy to retract, support, or modify my statement.

  24. 74

    Dr. Archer, on modern agribiz meat: “By calories, it would be more efficient to eat fossil fuels directly.”

    Depressing from (at least) two distinct perspectives: environmentalist and diner.

    But Kroger here has at least started offering local, grass-fed beef (and at a fairly reasonable price, too.) Of course, that just ameliorates, it doesn’t solve; everything is still transported, processed and packaged largely on FF power, this being Georgia (where energy experimentation is at a very low ebb.)

  25. 75
    Geoff Beacon says:

    Jim Eager #70

    Methane from ruminant digestion is analogous to CO2 from respiration, neither are net additions.

    That doesn’t matter. If we killed all the cattle and ate them now, it would buy us some time to come to our senses, cut down our carbon emissions and begin to extract carbon dioxide from the atmosphere. Of course I would “go after” rice production – when it is produced in methane producing paddy fields.

    The sensible way to “go after” emissions of greenhouse gasses would be pollution taxes – or as I would prefer to call them “pollution fines”. I would try a fine of something like $300 to $500 per tonne of CO2e.

    One mechanism that I like (not the only one) is Jim Hansen’s “Carbon fee with 100% dividend”. All the revenue raised would be paid back to every citizen in equal amounts. It would radically change the way we live and give our decendants a little bit of a chance to survive.

  26. 76
    dbostrom says:

    Kilian, I think I see your point but (for instance) extrapolation on what might happen to thermokarst lake expansion is not useful as a solid foundation for further research or policy evolution without a reasonably hermetic explanation of how that extrapolation is derived, which of course requires meticulous work to be performed.

    Our intuition suggests to us what’s going to happen here but intuition doesn’t work when it comes to application. Intuition is often wrong and in any case it doesn’t serve as a placeholder for reason.

    You ask “has anyone bothered?” in reference to doing thermokarst projections but that brings us directly back to “who is going to do those?” I don’t think there’s a deep well of idle scientists available for this.

    It’s not fair or helpful to bludgeon the few people capable of producing the results you wish for with complaints that they’re not prepared to abandon their discipline and begin rattling off speculations in advance of their practice. You’re asking for shoddy output.

  27. 77
    wili says:

    David, responding to a point I made at #56, said:

    “I’m skeptical it could happen but even if it did, what it would do would be to give us a preview of what 2100 will be like under business-as-usual. One that would immediately begin to subside, instead of inexorably worsening and lasting forever like the CO2 impact by 2100. Might lead to the human awareness tipping point you’re looking for.”

    I have often wondered about that possibility, but mostly kept it to my self, lest someone accuse me of hoping for a disaster. Given the many major disasters that have already occurred that can be pretty clearly pinned to AGW but that have failed to convinced many of the (faux-)’skeptics,’ I doubt any event or set of events in the world will ever sway their minds.

    Above, I cited an article at #25 that afforestation of the Arctic is happening much faster. Now there is evidence that these will exacerbate warming for reasons beyond albedo (though see the articles Jim linked to above at #25 for the fuller, more complex picture on that.) New trees actually cause more new carbon emissions than they absorb:

    “Carbon shown to rise as trees replace tundra”

    http://www.brisbanetimes.com.au/environment/climate-change/carbon-shown-to-rise-as-trees-replace-tundra-20120618-20jqh.html#ixzz1yHKLUvsH

    “In a surprise finding, researchers have shown that as trees start to grow closer to the North Pole, replacing once-barren tundra, they release more greenhouse gases than they absorb.

    The study has global implications for measuring the speed of global warming because it had previously been thought that when forests colonise the frozen Arctic, they might act to slow climate change by soaking up extra carbon dioxide from the air.

    Instead, as temperatures rise and plants take root further north, the barren soils are “primed” by new growth and start to release long-held stocks of carbon. The amount of carbon activated by a change from tundra to forest outweighed that soaked up by the new trees, leading to a net increase in the amount that ends up warming the atmosphere…

    The study’s findings identify just one of the complications of recent warming that could lead to much faster temperature rises this century. They include the potential release of large amounts of heat-trapping methane from thawing Arctic soils and the large-scale release of emissions from peat in the tropics.”

    So not only is afforestation happening much faster than anyone thought possible, it is a double-whammy for accelerating warming–both from albedo change and by stimulating more carbon release than the trees absorb. As we all know, all these feed backs also feed on each other creating a very complex and volatile system that is is difficult to model accurately.

  28. 78
    Ray Ladbury says:

    Killian, I know of no mechanism for clathrate decomposition that is sensitive to human population. As a matter of fact, I believe it is a purely thermodynamic process and so is driven by pressure and temperature entirely.

    Now surely it is not your intent to suggest we’ve never had methane/clathrate deposits of the kind we now see. If that is the case, why did the bomb not go off in the past at temperatures comparable to the ones we see now.

    And even if we were to find the bomb about to go off, what, pray, would we do about it other than what we should be doing anyway, which is limiting our own ghg output? CO2 is the control knob. It applies both throttle and brake depending which way we dial.

  29. 79
    Jim Eager says:

    Killian wrote: “The deposits we are worried about have largely been laid down during the Ice Age era, correct?”

    The “Ice Age Era” would be the last 2.5-2.75 million years, comprising repeated deglaciations, several of them warmer than present. But sea bed clathrates have been accumulating for far longer than that. The last sudden large jump in temperature that could conceivably have triggered large-scale clathrate releases looks to have been the sudden (geologically) thawing of the Antarctic ~25 million years ago, with reglaciation beginning ~12-13 mya, so clathrates have been accumulating for at least that long. As Hansen says, the clathrate “gun” is presently fully charged and loaded, but we know that it didn’t go off during any of the past interglacials of the Pleistocene. As I said, not until we reach and exceed those past interglacials will we be in uncharted territory, and earth’s history tells us that it’s there be the dragons, and we aren’t there yet.

  30. 80
    Jim Eager says:

    So, Geoff, you would simultaneously slaughter the global cattle population (including dairy herds?) and some how ban paddy rice production, at the same time ocean fish stocks are in a death spiral?

    There’s 7 billion people on the planet, roughly half of them currently dependent on rice for most of their calories. How do you propose to feed those 7 billion, Geoff?

    There truly be madness.

  31. 81
    dbostrom says:

    Jim: …and some how ban paddy rice production…

    Call it picayune small time thinking but it would be nice to at least have a decent carbon budget on the paddies before the killings commence.

  32. 82
    Susan Anderson says:

    This cannot be good for permafrost (very far north; the area is relatively small):

    On June 18, 2012, a total of 198 wildfires burned across Russia and had charred an area that covered 8,330 hectares (32 square miles). Many were in central Russia, where firefighters have battled uncontrolled fires for months.
    The latest flare-up prompted Russian authorities to declare a state of emergency in seven regions, including the Khanty-Mansiisk autonomous area, the Tyva Republic, the Sakha Republic, Krasnoyarsk, Amur, Zabaikalsky, and Sakhalin.
    ….
    According to Russian authorities, many of the fires started when people lost control of agricultural fires and campfires. However, lightning sparked some of the blazes as well.
    According to the environmental group Greenpeace, more land in Russia has burned this year than in 2010, a year that intense wildfires affected western Russia and produced rare pyrocumulus “fire clouds.”

    http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=78305&src=nha

  33. 83

    Since it is a matter of interest and importance (to me, at least) to have a better grasp of the similarities and differences between the last interglacial and now, can anyone point to a paper or papers that delineates these differences?

  34. 84
    dbostrom says:

    Susan: On June 18, 2012, a total of 198 wildfires burned across Russia and had charred an area that covered 8,330 hectares (32 square miles). Many were in central Russia, where firefighters have battled uncontrolled fires for months.

    One Russian President and one US Presidential candidate: When it comes to firefighters, don’t get carried away and go overboard on hiring. What possible reason could we have for more firefighters?

    Russia is leading the way on monetizing their landscape and the man from Bain is paying close attention. Pay no attention to the flames.

  35. 85
    Chris Colose says:

    Tenney,

    The AR4 had a good discussion of the last interglacial here though some details are now out of date.

    As a “broad brush” picture, the last interglacial is highlighted by positive insolation anomalies (incoming solar radiation) during boreal summer in the Northern Hemisphere, and austral spring in the Southern Hemisphere. Global mean annual temperature anomaly is not very well resolved due to uncertainties in the seasonal expression of proxy records, and data coverage, but possibly 1-2 C warmer than the mid 20th century (e.g., Turney and Jones, 2010; though see Rashid et al. ,2011, JQS) and larger at higher latitudes (possibly 5 C in Antarctica (e.g., Sime et al., 2009, Nature); sea levels are at least 6 m higher than present, a bit higher than values cited in the AR4, and possibly up to 9 m (see e.g., here).

    (There are model simulations of this time-period post AR4 but I have not looked at them, though I believe they don’t quite get the observed magnitude of many of the changes…someone else will need to elaborate on this if you are interested).

  36. 86
    wili says:

    “It has never happened before, therefore it can never happen.”

    Does this strike anyone as sound logic?

  37. 87
    Geoff Beacon says:

    Jim Eager, #80
    Jim,

    How do you propose to feed those 7 billion, Geoff?

    Answer number 1. Capitalism will provide. That is a properly guided capitalism. It will fine the polluters on their carbon emissions with the fines 100% returned to every citizen. It will not be spent by governments beholden to the powerful. This means the polluters loose and the gentle will gain. Blessed are the meek: for they shall inherit the earth. Matthew 5:5.

    How do you propose to feed those 7 billion, Geoff?

    Answer number 2. We are not short means to produce food. It’s the poor that starve because we eat foods that require enormous resources.
    In Ireland before the famine, potatoes, with some milk and pigs could support a population density approaching 10 people per hectare. The world now has about 0.5 people per hectare. That’s about 5% of the population density of pre-famine Ireland.

    How do you propose to feed those 7 billion, Geoff?

    Answer number 3. Destructive foods will become expensive. Beef, lamb and venison will be priced off most people’s plates, most of the time. With my carbon dividend, I will find less destructive foods such as Quorn, TVP and beans more affordable. For desperate carnivores there are other meat options like chicken and pigs.

    With ocean acidification fish in the seas may be a problem but fish farming is already coming to the rescue.

    But under properly regulated capitalism, the market will determine the prices and consumption patterns. From time to time, just as an experiment, I might even try a small amount of beef jerky, which will become much more expensive.

    How do you propose to feed those 7 billion, Geoff?

    Answer number 4. Market forces. Market forces. Market forces. (Properly regulated).

    See: Why the answer is a carbon tax by Tim Worstall from the Adam Smith Institute.

    P.S. You don’t need paddy fields to grow rice.

  38. 88
    Geoff Beacon says:

    Susan Anderson #82.

    … and the increasing frequency of wildfires is not in the climate models. John Mitchell said earlier this year

    more forest fires – We don’t do yet, but could be important for changing ecosystems response to climate.

    See EU climate policy badly out of date?

  39. 89
    Jim Larsen says:

    60 Thanks for the response, David. I agree with you, especially on the “permafrost thaws slowly” point. I’d add that the more permafrost you thaw, the harder it is to thaw some more. It takes a lot of time for heat to get down to 1000 meters. That’s perhaps a hundred thousand years+ worth of thawing to finish the job.

    Anyway, just to make it clear, the OP makes sense to me and I’m not in the “methane catastrophe” camp. Yep, much of the shallow permafrost is going to thaw and as the “thaw front” advances, massive amounts of methane will be released. (though “massive” doesn’t necessarily mean big enough to make a serious difference in a gargantuan system like the Earth) Given the huge area and depth, and diverse climate and geology, large methane releases ought to be scattered in space and time, resulting in what looks like a chronic release. How big? How fast? Will it be like a bell curve with a long tail as shallow permafrost thaws ever quicker and then stuff slows down as deeper soil is better insulated? If so, we could be looking at a pulse of perhaps a few decades followed by centuries of chronic release. However, there’s the niggling special case of the ESAS and Dr S’s 50gt release scenario. I’m patiently waiting for more research to quantify the probability of her speculation.

    Your point that time is [at least] as important as maximum temperature (Time * Temp C?) seems to detract from Ray’s “safe for now” argument. This stuff has been thawing for ~8,000 years, especially the ESAS. Also, we’ve debated about whether the LIA and MWP even existed. Spaghetti graphs show 0.5C deviations in estimates for global temperatures in the very recent past. What sort of deviations in time, temperature, and location are reasonable for half a million years ago? Can we say with confidence that the ESAS has received less total thawing power this time around (so far)?

    Ray, you mentioned ocean thermal lag as a factor increasing clathrate stability. Limiting this to the ESAS, where we’re talking 15-50m depth, is there much lag? I’ve been of the impression that it’s mostly an iced-over or clear water issue. In the early Holocene, lots of open water and sunshine reaching the ESAS bottom. Then, slow heating as ice mostly covered the ESAS. Now, we’re entering an era where the ESAS will again be mostly open water for the whole summer.

    So if I agree with the OP, what’s my fear? Why not brush this off as not big enough to worry about? Well, our 2C calculations are looking tenuous even with the assumption that the land and ocean will continue to suck up carbon, so there’s no wiggle room for beetle-kill, fires, the Amazon shrinking, permafrost and clathrates thawing and any other carbon feedbacks. So yep, it ain’t a methane catastrophe and methane will probably be just a blip on its way to transforming into more CO2, but methane and other “natural” carbon feedbacks look to be potent enough as a group to ensure we miss the 2C target.

    80 Jim E said, “There’s 7 billion people on the planet, roughly half of them currently dependent on rice for most of their calories. How do you propose to feed those 7 billion, Geoff?”

    There’s no requirement for anybody to eat rice. There’s lots of different crops to choose from. Geoff simply wanted to include the true costs of rice farming in rice prices. That way people could continue to grow rice in paddies, grow less destructive crops, or switch to dry rice farming, as described here:
    http://www.hope-international.com/projects-and-programs/sustainable-agriculture/dry-rice-farming.html

    You seem to be suggesting that “Since folks currently grow rice in a climate-damaging way, they should continue to do so in the future at no cost.” Well, substitute “burn coal” for “grow rice” and what’s the moral, ethical, or logical difference? I say we should have a GHG playing field as level as a rice paddy. Agricultural releases of GHGs should have no preferences over emissions from somebody who burns oil in a Hummer. Now, before someone screams about poor indigent rice farmers, I’ll point out that such folks most likely emit less than the world average GHGs and so would get checks from America and Europe and such places. Their motivation to adopt dry rice farming or grow wheat or whatnot would be to increase their annual GHG check.

  40. 90
    wili says:

    To Jim Larsen at #89 who writes: “I’d add that the more permafrost you thaw, the harder it is to thaw some more. It takes a lot of time for heat to get down to 1000 meters. That’s perhaps a hundred thousand years+ worth of thawing to finish the job.”

    Perhaps that is true “to finish the job,” but the main post shows that we don’t have to wait hundreds of thousands of years for methane to leak out–methane is seeping out now, and it is on the increase. The only question is how fast this increase is going to take place.

    And again, the pools of free methane gas we’re talking about don’t have to wait for all of the overlying permafrost to thaw. Just a crack, perhaps from the deep roots of one of the new trees now growing in the tundra, to provide a route for its escape into the environment is sufficient.

    But really, for the long-term prospect for life on the planet, a slow release is probably the worst thing. It insures that GW will be extended for many millennia or more beyond what it would have been, even if industrial society no longer poses a direct threat.

    As for ““massive” doesn’t necessarily mean big enough to make a serious difference in a gargantuan system like the Earth,” I think you may want to re-read the abstract to the article.

  41. 91
    MARodger says:

    wili @86
    You ask “Does this strike anyone as sound logic?” Well, if it doesn’t yet, “There’s always a first time for everything.”

    Without a source for your pro-offered quote, I speculate by suggesting perhaps what was meant was the rather pedantic “It has never happened before, therefore it cannot be happening again.” which would be logically sound.
    Or it could be an overly robust version of “It has never happened before, therefore I am not convinced it can ever happen.”
    Then again, if your source doesn’t regard illogic comment as a problem, you will have to take a crash course in Idiotese.

  42. 92
    wili says:

    Geoff B, I can’t go along with your optimism that capitalism will save everything. Why hasn’t it done so already?

    Capitalism is at base an economic system that benefits capital (and those that have it), rather than a system whose goal is benefiting society (that would, of course, be social-ism). (We have yet to fully develop and economic system designed to benefit the living planet–geo-ism? eco-ism? bio-ism??)

    The winners in capitalism have acquire capital=power which they always use primarily to gain more capital=power. Part of how they use their power to get more power is by influencing policy with vast quantities of money. Those who have gained power through ff (arguably the most concentrated and useful form of energy/power) will use and are using their considerable power to block any effort to increase taxes on carbon.

    Industrial capitalism has proved to be a very powerful and efficient mechanism to turn our beautiful blue planet into a toxic wasteland. I am dubious that greed can be an equally efficient mechanism to restore the same.

  43. 93
    Geoff Beacon says:

    Low rainfall, poor harvests, high food prices and a lack of pasture are all causing serious problems across the Sahel region. Oxfam aims to reach 1.2 million with emergency support.

    West Africa food crisis

    Isn’t this how climate change affect the world?

    I’m chairman of a small organisation, the Pollution Tax Association. We have been paying voluntary “carbon taxes” since 1992 and mostly give the proceeds to charity.

    These people are starving because they are poor – not because there is insufficient food in the world. It’s the poor that starve.

    Send them your carbon fines now.

    Pay them more if they give up their cattle.

  44. 94
    Ray Ladbury says:

    Wili: ‘“It has never happened before, therefore it can never happen.”

    Does this strike anyone as sound logic?’

    It strikes me as a distortion (deliberate or not) of the argument. What is actually being said is that the physical conditions we are currently experiencing have occurred before without the realization of this phenomenon, as such we are likely not at risk until conditions become more severe.

  45. 95
    Jim Eager says:

    Geoff, your reply sounds almost exactly like what is coming out from the lukewarmers and even the fake skeptics.

    We’re talking ~3.5 billion people current dependent on rice. We’re talking large parts of southeast Asia already at or near the maximum temperature that allows successful germination of rice. We’re talking expected, nay, already observed drying of continental interiors, which will render large areas of presently arable land unsuitable for large scale agriculture as glacial reservoirs and aquifers are drawn down, simultaneous with increased occurrence of extreme precipitation events, i.e. disruption of the a predictable hydrological cycle that makes large scale agriculture possible. Your belief in the ability of capitalism and agriculture to keep up with these changes is shockingly naive.

    The world has a present population density of about 0.5 people per hectare for a reason(s). We can’t farm in deserts without consuming large quantities of scarce water. We can’t farm in rain forests without clear cutting them and importing large quantities of fertilizers to compensate for the already mined-out soil. We can’t farm areas of exposed bedrock and shallow mineral soils, period. We can’t farm muskeg and tundra without first draining it and raising it’s pH. This is lying with statistics of the first order.

    I share your desire for the implementation of a carbon tax & dividend system, but we’ve been waiting for a functioning carbon pricing mechanism for well over a decade now. Cap & trade systems are too easily gamed. Australia is finally taking it’s first step to a carbon tax system after a tooth and nail fight, but it could be reversed the next election. The US and Canada (at least on a national level) are still fighting it tooth and nail. It’s simply not happening fast enough.

    Sorry, I just don’t share your optimistic belief that the existing political and economic systems will or even can deal with what is happening much less what will happen.

  46. 96
    Ray Ladbury says:

    Geoff Beacon: “We are not short means to produce food.”

    Uh, actually we are, at least sustainably. We tend to take the gains of the Green Revolution for granted, but they were attained at great cost to the environment and carrying capacity of the planet. Yields are maintained by fossil-fuel derived chemicals that run off into water bodies causing algal blooms and anoxia. Aquifers are depleted. These are one-time windfalls that once depleted will be lost for good.

    Feeding, clothing and housing 10 billion people without permanently degrading the carrying capacity of the planet is not a trivial problem, and cavalier suggestions of crop substitution devoid of serious study are not helpful.

  47. 97
    Jim Eager says:

    Jim Larson: “There’s no requirement for anybody to eat rice. There’s lots of different crops to choose from.”

    Are there? Different crops require different growing conditions, different moisture levels, different maximum and minimum temperatures, different soil conditions and nutrient constituents, different climate zones. And those zones and conditions are already shifting for those different crops. Present alternatives may not work in the future because future conditions will be different.

    No, I’m not saying “since folks currently grow rice in a climate-damaging way, they should continue to do so in the future at no cost.” I’m saying they are currently growing rice in a climate-damaging way and they are currently dependent on that rice. The replies so far would change that with the sweep of a hand without giving serious thought to what would replace those crops on a large enough scale and how, given that all agriculture is already coming under stress and shifting conditions and those stresses will continue to increase as conditions shift. Present alternatives may not work anywhere in the future.

  48. 98
    dbostrom says:

    Jim Larsen: …it ain’t a methane catastrophe and methane will probably be just a blip on its way to transforming into more CO2, but methane and other “natural” carbon feedbacks look to be potent enough as a group to ensure we miss the 2C target.

    And elsewhere mentioned the word “chronic” in connection w/seeping C02.

    I’ve read persuasive explanations about why we need to bring anthro C02 emissions essentially to a complete halt in order to avoid accumulation problems; “reduce by 80% by 2050″ leaves a 20% ongoing remainder as an unacceptable amount of emissions. The various emissions Jim enumerates count as anthro C02, are presumably just as destructive as what emerges from a tailpipe and can’t be controlled.

    Definitely feeling like we’re screwed, this morning.

    Does anybody have a pointer to the actual C02 budget on rice (skipping the methane step which is transient), something reliable? I’m not quite getting from where the net -addition- of carbon from rice cultivation is derived, unless it’s synthetic fertilizer.

  49. 99
    Steve Fish says:

    Re- Comment by Geoff Beacon — 20 Jun 2012 @ 7:41 AM:

    Regarding the starving poor you say- “Pay them more if they give up their cattle.”

    The thing about a cow on a subsistence farm is that it can provide meat and milk from land which is too poor to farm and no irrigation is available for practically no cost. The animals pretty much take care of themselves and convert cellulose from dry grass into food. There is no fossil carbon involved, the soil is actually improved in this kind of situation, and the methane released is close to net zero because it was made from CO2 that was already in the air. Such ignorance!

    Steve

  50. 100
    dbostrom says:

    After just a bit of rummaging, I found this article on rice farming, which seems to tell the story reasonably well.

    So where’s the net contribution of C02 coming from? Paddies appear to be working as a component of carbon flux but– short of magic– I don’t see from where the net addition to the total carbon in circulation is derived.

    Expansion of paddies unlocking previously stored organic surface deposits?

    Waiting to be corrected; Corporal Dunning-Kruger reporting for duty, Sah!


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