RealClimate logo

Irreversible Does Not Mean Unstoppable

Filed under: — david @ 1 February 2009 - (Italian) (Finnish) (Chinese (simplified)) (Español)

Susan Solomon, ozone hole luminary and chair of the Nobel Prize winning IPCC, and her colleagues, have just published a paper entitled “Irreversible climate change because of carbon dioxide emissions” in the Proceedings of the National Academy of Sciences. We at realclimate have been getting a lot of calls from journalists about this paper, and some of them seem to have gone all doomsday on us. Dennis Avery and Fred Singer used the word Unstoppable as a battle flag a few years ago, over the argument that the observed warming is natural and therefore there is nothing that humanity can do to alter its course. So in terms of its intended rhetorical association, Unstoppable = Burn Baby Burn. But let’s not confuse Irreversible with Unstoppable. One means no turning back, while the other means no slowing down. They are very different words. Despair not!

Solomon et al point out that continued, unabated CO2 emissions to the atmosphere would have climatic consequences that would persist for a thousand years, which they define operationally as “forever”, as in the sense of “Irreversible”. It is not really news scientifically that atmospheric CO2 concentration stays higher than natural for thousands of years after emission of new CO2 to the carbon cycle from fossil fuels. The atmospheric CO2 concentration has a sharp peak toward the end of the fossil fuel era, then after humankind has gone carbon neutral (imagine!) the CO2 concentration starts to subside, quickly at first but after a few centuries settling in a “long tail” which persists for hundreds of thousands of years.

The long tail was first predicted by a carbon cycle model in 1992 by Walker and Kasting. My very first post on realclimate was called “How long will global warming last?”, all about the long tail. Here’s a review paper from Climatic Change of carbon cycle models in the literature, which all show the long tail. A number of us “long tailers” got together (electronically) to do a Long Tail Model Intercomparison Project, LTMIP, just like the big guys PMIP and OCMIP (preliminary results of LTMIP to be appearing soon in Annual Reviews of Earth and Planetary Sciences). I even wrote you guys a book on the topic.

The actual carbon-containing molecules from the fossil fuel spread out into the other carbon reservoirs in the fast parts of the carbon cycle, dissolving in the oceans and getting snapped up by photosynthetic land plants. The spreading of the carbon is analogous to water poured into one part of a lake, it quickly spreads out into the rest of the lake, rather than remaining in a pile where you poured it, and the lake level rises a bit everywhere. In the carbon cycle, translated out of this tortured analogy, the atmospheric carbon dioxide content rises along with the contents of the other carbon reservoirs.

Ultimately the airborne fraction of a CO2 release is determined largely by the buffer chemistry of the ocean, and you can get a pretty good answer with a simple calculation based on a well-mixed ocean, ignoring all the complicated stuff like temperature differences, circulation, and biology. The ocean decides that the airborne fraction of a CO2 release, after it spreads out into the other fast parts of the carbon cycle, will be in the neighborhood of 10-30%. The only long-term way to accelerate the CO2 drawdown in the long tail would be to actively remove CO2 from the air, which I personally believe will ultimately be necessary. But the buffering effect of the ocean would work against us here, releasing CO2 to compensate for our efforts.

As a result of the long tail, any climate impact from more CO2 in the air will be essentially irreversible. Then the question is, what are the climate impacts of CO2? It gets warmer, that’s pretty clear, and sea level rises. Sea level rise is a profound consequence of the long tail of global warming because the response in the past, over geologic time scales, is tens of meters per °C change in global mean temperature, about 100 times stronger than the IPCC forecast for 2100 (about 0.2 meters per °C). The third impact which gains immortality from the long tail is precipitation. Here the conventional story has been that climate models are not very consistent in the regional precipitation changes they predict in response to rising CO2. Apparently this is changing with the AR4 suite of model runs, as Solomon et al demonstrated in their Figure 3. Also, there is a consistent picture of drought impact with warming in some places, for example the American Southwest, both over the past few decades and in medieval time. The specifics of a global warming drought forecast are beginning to come into focus.

Perhaps the despair we heard in our interviewers’ questions arose from the observation in the paper that the temperature will continue to rise, even if CO2 emissions are stopped today. But you have to remember that the climate changes so far, both observed and committed to, are minor compared with the business-as-usual forecast for the end of the century. It’s further emissions we need to worry about. Climate change is like a ratchet, which we wind up by releasing CO2. Once we turn the crank, there’s no easy turning back to the natural climate. But we can still decide to stop turning the crank, and the sooner the better.

Walker JCG, Kasting JF. 1992. Effects of fuel and forest conservation on future levels of atmospheric carbon dioxide. Palaeogeogr. Palaeoclimatol. Palaeoecol. (Glob. Planet. Change Sect.) 97:151–89

210 Responses to “Irreversible Does Not Mean Unstoppable”

  1. 51

    Great that you highlight this subject. I think that especially the unstoppable decay of ice sheets and sea level rise is an area that makes people almost give up. Despair is not constructive.

  2. 52
    mark s says:

    RE 31

    Gavin said…

    [Response: The impact of climate change on seismic events/volcanoes/tsunamis etc. is not something one needs to worry about – the forces controlling those phenomena are vastly in excess of anything we will be able to do to the Earth’s crust. There is possibly an exception to this related to changes in isostatic loading associated with melting ice sheets, but even there we have a very long way to go. There are important stewardship issues raised by the CO2 problem, but this is not likely to be one them. – gavin]

    I posted about this issue approx a year a go and was pretty much told that this issue was not something you (lovely) guys were takin seriously, and clearly this is still the case.

    I didn’t really hear a proper rebuttal of Bill Mcguire’s evidence, but i realise that it isn’t helpful to talk about effects we are not sure about, when there are plenty of more well established problems we are certain to face. So i left it at that.

    But when i read Gavins response, i immediatly thought of McGuires work, particularly in relation to the statement ‘the forces controlling those phenomena are vastly in excess of anything we will be able to do to the Earth’s crust’.

    I’m not suggesting that we are sure to see these kind of problems, but i think it is worth hedging our bets when making light of these possibilities, and i think that Gavins final statment,’There are important stewardship issues raised by the CO2 problem, but this is not LIKELY (my capitals!) to be one them.’, is far more accurate than the ‘don’t worry about it’, at the start.

    Anyway, as i said last time i brought this up, Bill McGuire is a pretty well established and respected earth scientist, and is certainly worth a read, even if you are skeptical that humanity could influence volcanic activity.

    here are details of the article i posted last year, note the work on the Pavlof volcano in Alaska, i believe this was done by either McGuire or some of his associates…

    here is a round-up of other articles he has had published in the Guardian,

    and in fairness some of the things he has flagged up are not currently thought to be that likely (ie ocean current disruption). But please don’t try and tell me that he is making suggestions about fields he doesn’t know much about. It wasnt true last time, and it isnt true now…

    Maximum respect to all at RC anyway, even tho i’m gonna get pasted for this suggestion. :-)

    Mark S

    here is a short biog of McGuire…

  3. 53

    We do not have to wait for nature to remove the exess carbon, as Solomon et al seem to assume. Olivine mining can help. Natural weathering of this mineral currently removes about 2 billon tons of CO2 from the atmosphere every year. We can speed up the process and remove as much CO2 as we want from the air and the oceans. At a cost, but it definitely is affordable, and the mineral is abundant. See

  4. 54
    X says:

    Re: #25 Nigel Williams

    Just regarding the figures mentioned, the 3000 GtC discussed in Charbit (2008) refers to cumulative anthropogenic emissions, not the total quantity in the atmosphere. Also, the unit GtC indicates the mass of the carbon component of CO2 only, so 3000 GtC is about 11000 GtCO2. The ‘3000 GtC scenario’ of the paper corresponds to a peak atmospheric concentration of 1215 ppm according to figure 1.

  5. 55
    Captain Trips says:

    I got a question about the estimated sea level rise. If the sea level rises, there will be definitely a lot of plants which die. All the forests, fields etc. with plants on it will not be able to survive.
    As far is my understanding goes, this will have two effects. The first effect is, there will be more nutrients in the sea. This will lead to a growth of algae. And the second effect is, that the dead biomass will cause an emission of CO2.

    Are there any models for this effects? Are this effects significant? Or will they be negligible? And what effect do they have on the life in the sea? If forests get inundated, with the nutrition rich soil this may lead to an increased growth of dead zones. Or is the timescale of the increasing sea level rise too big and the extra nutrients just are used by normal sea life?

  6. 56
    Geoff Beacon says:


    The absolute methane sink increases with increasing concentration


    with increasing methane emissions the OH level will likely drop

    If OH is the major methane sink, is there a contradiction here?

    How does the absolute methane sink increase with increasing
    concentration? Is the CH4/OH reaction limited mostly by methane

    If methane emissions increased by 100Tg per year, each year, how
    much would methane concentrations rise?

    A further question:

    What would the rise be if methane concentrations were twice the present level? (say 3600 ppb rather than 1800ppb)

  7. 57
    Ray Ladbury says:

    Jim, The first thing we need to do is buy time. Every watt of energy we don’t use is time. Put enough of those together, it’s a coal-fired power plant that doesn’t need to be built. Then we need to use that time push science and technology as hard as we can to come up with solutions, with better models to quantify the risk, with mitigations. We’ve wasted 15 years arguing with the scientists about the science. Now it’s time to see if they can save our tuckuses and what they need to do so.

    How would you rather answer your grand children’s query of what you did in the crisis:

    “I worked my butt off to preserve a future for you.”


    “I partied out, man.”

  8. 58
    Geoff Beacon says:


    Looking at

    If we could magically hold the OH level in the atmosphere constant, then methane lifetime would be constant, so the sink would be directly proportional to the concentration. d[CH4]/dt = [OH]*[CH4]

    This helps me understand my question better. I understood that methane was the main exit route for OH from the atmosphere. I also understood that the reaction stops at night because all the dalight OH is consumed.

    This made me believe that OH not methane is the limiting factor in this reaction. Have I got this wrong?

    Anyway thanks for your help.

  9. 59
    dhogaza says:

    But, I’m a bit confused about reading this article on CO2 and it’s
    warming effect noted in Antartic ice core samples.

    Jonas, the first step is to understand that Watts’ blog’s sole reason for existence is to confuse you. To convince you that climate scientists aren’t doing science, but rather are engaged in a fraudulent conspiracy to force society to adopt certain political policies.

    So you have a choice. You can learn about climate science from climatologists (like those running real climate), statistical analysis of climate time series data from statisticians (like tamino), etc or you can learn a distorted, dishonest, paranoid misrepresentation of science from people like Watts.

    If you read Watts to learn about climate science, you might as well spend the rest of your spare time reading Answers In Genesis to learn about modern biology.

  10. 60
    Marcus says:

    #58: Geoff Beacon: OH is the main exit route for methane… however, there are a wide number of different exit routes for OH (reactions with VOC, CO, SO2, etc.): I’ve heard OH nicknamed “the vacuum cleaner of the atmosphere” breaking down 3.7 gigatonnes of reactive gases in the atmosphere every year.

    If you were to increase methane emissions by 100 Tg every year, methane concentrations would rise until they reached a new equilibrium level. If we presume we’re at equilibrium now, and total methane emission (natural + human) are about 600 Tg, then our sink is about 600 Tg, so 600 = k*1.8ppm.

    That means that, absent feedback effects, 100 Tg of extra emissions would eventually cause concentrations to rise from 1.8 ppm to 2.1 ppm. I’d have to actually do some modeling runs to tell you what the feedback would do, but my guess is it would about double or triple that change at equilibrium… (actually, in a couple weeks I’ll have an answer to this question, since I’m doing some calculations on what a 100 Tg reduction in methane emissions for 100 years would do: it does depend on baseline assumptions and NOx/VOC/etc. emissions though, which makes it more complicated)

    Also, there really isn’t a limiting factor, at least in the sense of running chemical reactions in a beaker where the reaction stops once one reagent is used up: the “consumed” OH goes to HO2, and if NOx is around, the HO2 gets catalytically recycled back to OH: also, sun + H2O produces OH, so while you can depress the amount of OH around, you won’t completely get rid of it, and its lifetime is measured in seconds anyway: conversely, methane does have a 10 year lifetime, so there’s always a decent amount of methane around.

  11. 61
    John L. McCormick says:

    RE # 44

    Marcus, you said:

    [we’d probably return to near preindustrial OH levels fairly quickly]

    Have you considered the positive feedback of a warming Arctic region melting the permafrost, warming the tundra and peat bodgs; thereby releasing massive amounts of CH4? In which case, we’d NEVER return to near preindustrial OH levels.

    John McCormick

  12. 62
    Lance Olsen says:

    I was hoping someone would mention the “carbon farming” option for carbon capture and storage. Not as a silver bullet, but as one in a set of responses necessary to adaption and mitigation.

    Threads of the carbon farm did show up, including that someone asked if anyone has looked at interactions of land use and climate, and another asked about websites where people can learn about proposals to take CO2 back from the atmosphere.

    According to a University of Iowa website, “On a world-wide basis, from the time agriculture began, almost 80 million tons of carbon have been released from the soil (Rattan Lal, soil scientist, Ohio State University). Up until the late 1950s, tillage (plowing) released more carbon dioxide into the atmosphere than all the burning of oil and coal in history. However, that’s all in the past and we can’t do anything about it. But what this does tell us is the potential for once again using the soil as a great storehouse of carbon. Theoretically, American soils could soak up more than 100 million tons of carbon annually. That’s enough to offset the emissions from half of the cars in the country.”

  13. 63
    John Bolduc says:

    David, I was feeling better after reading this post, but then I saw a paper that the Tyndall Center has published which is sending me back down. See The authors concluded that “it is increasingly unlikely any global agreement will deliver the radical reversal in emission trends required for stabilization at 450 ppmv carbon dioxide equivalent. Similarly, the current framing of climate change cannot be reconciled with the ates of mitigation necessary to stabilize at 550 ppmv CO2e and even an optimistic interpretation suggests stabllization much below 650 ppmv CO2e is imporbable.”

    Then I see a report by McKinsey & Co. that lays out a scenario for a potential 30% reduction below 1990 levels by 2030, which makes me feel better again.

    I think I’m getting whiplash. Can these reports and what you and Solomon say all be consistent with each other? Please help me understand.

    [Response: What answer are you looking for? We can do it. Will we, I dunno. David]

  14. 64
    Geoff Beacon says:


    Gosh thanks. I may regain some sanity.

    Looking at

    I’ve heard OH nicknamed “the vacuum cleaner of the atmosphere” breaking down 3.7 gigatonnes of reactive gases in the atmosphere every year.

    So it does lots more than remove methane.

    But I do share the concerns of John #61, especially as the Earth Systems Models used in IPCC AR4 did not include these feedbacks, but your last post suggests you will address this. Please keep us informed.

    Does you work have implications for the “methane is 23 times CO2” statement we hear so often. I gather from Wikipedia this GWP for methane is measured over 100 years. Is this GWP measure a useful tool for measuring carbon footprints? Footprints are a very important tool for policy making.

    Is 100 years a sensible time-scale, given probable feedbacks?

  15. 65
    John A. Davison says:

    I agree with Mark J. Fiore. I also agree with Martin Rees, President of the Royal Society and author of “Our Final Century.”

    I hate being right and pray I am wrong.

  16. 66
    Brian Allen says:

    Michigan just experienced its 5th coldest recorded January
    (NOAA). This makes it difficult for the layman (even myself, despite all that I have read and studied) to maintain a level of concern about irreversible warming from CO2. When is a cold spike in temperatures notable? It seems like the last two years demonstrate some notable variance in the warming trend rather than just a weather change. (not a denier just an observer)

    [Response: Weather variations don’t disappear because of a long term trend. The variance in january temperatures in Michigan probably has a standard deviation of a couple of degrees. The global warming we expect from CO2 etc. right now is around 0.2 deg C/decade. Which is 0.02 deg C/yr. So in any one or two winters, the natural variability is likely to swamp any long term trend. So it does take a long time for climate change to be clearly noticeable at the local scale – that’s why integrators of weather (like mountain glaciers, ecosystems etc.) are so useful at showing how the baselines (on average) are shifting. – gavin]

  17. 67
  18. 68


    As a fellow Christian I really appreciate what you’re doing. Taking care of the Earth God gave us to steward really should be a priority for believers. “The Earth is the LORD’s, and the fulness thereof” (Psalm 24:1). It’s his Earth, not ours, and we do not show him respect when we fill it with trash and play games with the climate.

  19. 69
    Jeffrey Davis says:

    Strep throat is a natural process. Does Fred Singer go to a doctor when he has a strep infection? Or does he only go to a doctor when he’s hit himself with a hammer?

  20. 70
    dhogaza says:

    Michigan just experienced its 5th coldest recorded January
    (NOAA). This makes it difficult for the layman (even myself, despite all that I have read and studied) to maintain a level of concern about irreversible warming from CO2.

    Along with Gavin’s climate-vs.-weather elementary point, please keep in mind that
    Michigan and the rest of the midwest etc are not the world. Even if you toss in the east coast and Texas.

    The West Coast of the US has been having a warm january. Here in PDX, inversion conditions have caused the city to have cold (but not exceptionally cold) nights but the same inversion has contributed to a low snowpack that already has water managers worried about summer.

    And Australia’s in the midst of a heat wave.

    So if you’re going to cite local weather as evidence that “climate science is bunk”, you might be well-advised to check whether or not that local weather is representative of what’s happening around the world …

  21. 71
    tamino says:

    Re: #66 (Brian Allen)

    The standard deviation of January average temperature in Grand Rapids, Michigan from 1888 to 2008 is about 2.66 deg.C. That’s 4.8 deg.F. Two standard deviations (about the 95% confidence level) is nearly 10 deg.F. That’s how much variation you can expect for a single January. So, observing the 5th coldest ever recorded is nowhere near an indication of “notable variance in the warming trend rather than just a weather change.”

    And while Michigan experienced its 5th-coldest recorded January, South Australia is recovering from their worst heat wave ever recorded, “enduring six consecutive days of temperatures reaching 113F (45C).”

    Neither event is proof or disproof of global warming. It’s the long-term trends globally, not the short-term events locally, that global warming is all about.

  22. 72
    Rod B says:

    re Jim Norvell’s reference in #45: I’m not familiar with AC News. Though it seems on my skeptic side, the article reads like a biased “agenda” piece. None-the-less are they accurate when the cite Hansen, “that carbon levels in the Earth’s atmosphere have become so high that a runaway greenhouse effect is all but inevitable unless drastic measures are taken. These include a ban on all coal fired plants and a carbon tax.

  23. 73
    Pat Neuman says:

    The layman can get an understanding of weather variablity vs climate trends by viewing temperature data at climate stations having at least 100 years of record.

    For example, temperature records at Muskegon, Michigan show an increasing trend (2 Deg. F, from 46-48, linear) based on annual mean temperature data from 1897-2007.

    Unfortunately, NOAA NWS offices have done nothing to educuate the public about temperature trends at climate stations. Warming trends have been strongest at climate stations in MN, ND and MT.

  24. 74
    Rod B says:

    Question: what is the CH4 + OH reaction (simple chemical formula)? Is this considered oxidation/burning of methane?

    [Response: It’s actually pretty complicated since there are many pathways involving multiple intermediate radicals. It all boils down to CH4 + 8OH –> CO2 + 6H2O in effect though. This is oxidation of CH4. Burning of methane uses O2, not OH. – gavin]

  25. 75
    Rod B says:

    dhogaza (59), saying the people who gave him the information are SOBs is not exactly answering his question about that information…

  26. 76
    James says:

    Brian Allen Says (2 February 2009 at 10:40 AM):

    “Michigan just experienced its 5th coldest recorded January…”

    Yeah? Wish you could ship some of that to northern Nevada: this time of year, I should be out skiing, instead I spend time in the garden pulling weeds.

  27. 77

    Jonas (50):

    The lag between CO2 and temperature increase is true (and known to climate scientists), but it’s wrongly interpreted in the source you’re referring to (and at many other places as well). I call those wrongly interpreted facts ‘half truths’

    I replied at WUWT as follows:

    This article correctly states that the temperature started to increase before the CO2 did at the end of an ice age. (This was apparently predicted by Hansen before it was observed in ice-cores, and is currently well known in climate science.) However, the interpretation that CO2 does not influence the temperature is wrong. Temperature and CO2 influence each other in both directions; it is a bit of a chicken-egg discussion. The IR absorbing qualities of CO2 and other greenhouse gases were measured in the laboratory over 100 years ago. This basic piece of physics doesn’t go away by pointing at ice cores. To the contrary, it makes the picture complete: The amplification of the initial warming by GHG and the ice albedo effect are important to include when trying to understand the total amount of warming.

    However, the current situation is clearly different from that at the end of the ice ages, since now we know that the extra CO2 is brought into the atmosphere by human activity. Currently, CO2 is not increasing in response to the warming, but rather due to human emissions, and as such it is now one of the driving forces of the warming. If you claim that the current increase in CO2 is due to the increasing temperature instead (not directly stated, but the reader is led to that conclusion, and rather successfully judged from the comments), then where did all the CO2 go that we’ve emitted so far? How come the isotopic signature of atmospheric CO2 has changed? (A reflection of a larger fraction of fossil carbon) And how could one reconcile the absence of warming from CO2 with the observed properties of this and other gases in the lab?

  28. 78
    Rod B says:

    Gavin (74), I guessed it was complex, which is why I asked for “simple” — just looking for the ballpark. Thanks. Is there any “slow burning” of methane in the atmosphere with O2? If so, is it significant?

    [Response: Not really. O2 is pretty stable, and only comes into this as a source for O3 through photolysis. This schematic might help visualise what is going on. – gavin]

  29. 79
    Marcus says:

    Re: 74: Gavin, I agree on the “pretty complicated”, but I’m not sure I like your choice of equation that you boil everything down to. An equally valid interpretation, assuming available NO, OH, and sunlight, would be:

    CH4 + 8O2 + hv -> CO2 + 4O3 + 2H2O

    Which frames OH as more of a catalytic role, and additionally nicely demonstrates the methane -> background ozone link (eg, West, Fiore et al. PNAS 2006). (one of the reactions in which the NO is used is to regenerate OH from HO2, and the NO2 then enters the ozone cycle)

    This webpage seems to summarize a bunch of hydroxyl radical chemistry:

  30. 80
    Marcus says:

    Oh. Nice schematic, Gavin. Yeah, that addressed my point.

  31. 81
    Benjamin P. says:


    My first time posting here as I only discovered this blog a few days ago because people at WUWT keep bad-mouthing “real climate” so I googled real climate and well, here we are!

    First, let me say it is nice to see some Real Science in the blog-o-sphere. Those dopes at WUWT blow my mind when they present articles and try to pass them off as science because there are a couple of graphs and some acronyms.

    That blog is really pretty disheartening to read as it just turns into a “Warmists are trying to steal your SUV” in the comments. Unfortunately, we as scientist have the difficult task of trying to communicate science to the general public. With such a low scientific literacy rate in this country it is easier for folks to fall prey to the pseudoscience over at WUWT then for folks to understand the real science.

    I teach Geology at a community college and the first day of class I always talk about science, what science can do and the limitations there of. Part of that discussion has to do with the language of science. I like to tell my students that understanding geology is two-fold: Learning the language and thinking critically about data.

    What we need to do as scientists is remember that our language is different than the non-scientists and we have to do our best to “translate” our results for the general public. So far, I have every indication that this site is doing well in that endeavor. Keep up the good work!

    Also, WUWT had a post about their web traffic for january being their busiest month. Since I just started visiting their site in Janurary I decidedc to post what I have learned in the month of January by visiting their site.

    This is my post:

    Things I have learned with my contributions of page views to your busiest month ever.

    1. Anecdotal evidence trumps most everything
    2. Al Gore is a Douche
    3. That Hansen guy is too.
    4. Models suck
    5. Warmists are energy communists who want to take away your SUV
    6. There is a secret geo-political agenda, but that agenda is loosely defined (or not at all)
    7. Warmists are only in it for the money
    8. Its easy to lie with statistics
    9. Figure Captions (something I tell my students are the 2nd most important part of papers (the first being the abstract)) tend to be lackluster and non-informative.
    10. Description of methodology does not happen
    11. Conclusions are met with 100% certainty (even if it is just a qualitative assessment of some graphs)
    12. CO2 does nothing to climate
    13. Sun spot cycles, while poorly understood, are the only short-term climate driver
    14. Consensus is bad (something we can all agree on)

    Did I miss anything?

    oh right…

    15. Pseudoscience and science are indistinguishable.

  32. 82
    Richard Ordway says:

    #31 Gavin, I have a question. You state “The impact of climate change on …tsunamis… is not something one needs to worry about.”

    Hmmm, let’s see the chain. The warming air heats up the ocean. The ocean heats up the bottom-residing methane clathrates. The methane clathrates dissolve, create an underwater landslide and a tsunami can result.

    No one knows for sure, but the Arctic ocean is shallow, has lots of methane hydrates and perhaps is warming up much faster than anyone had previously thought due possibly to the warm river inputs.

    Perhaps in the foreseeable future, climate-change induced tsunamis are not a big threat…but how about ~50 years or more in the future?

    On a similar issue, two recent preliminary studies, one Brit and the other Russian on possible current sharp Arctic ocean-bed methane clathrate release increases, if proved, after ten more months of publishing, suggest possible sharp changes and so, if I understand, might increase the possibility of future Arctic-based tsunamis beyond current expectations.

    [Response: Interesting scenario, but that would involve an enormous and explosive disintegration of hydrates. I’m not saying it can’t happen, but there is no sign that it can. The methane seeps that people are seeing are pretty continuous streams – that might be affected by bottom water temperatures of course – but I wouldn’t extrapolate that to anything beyond speculation at this stage. – gavin]

  33. 83
    Florifulgurator says:

    Charcoal anybody?
    I.e.: Stone Age Tech Carbon Capture & Storage!
    Also known as agrichar or biochar: Make charcoal of otherwise quickly decaying biomass and bury in the fields (or, rather, in the composts first).
    To go beyond Stone Age, make use of the syngas. E.g. my dreamcar would be the wood gas hybrid, fuelled by e.g. Miscanthus Sinensis. Drive CO2 negative!

    Sounds so f’n easy! Perhaps not techy enough? Where’s the catch?

    Lovelock mentioned it recently. Hansen has been mentioning it for some time. Apparently Pachauri didn’t know about it last year.
    What do the realclimate experts think?

  34. 84
    MarkB says:

    Re: #81

    Thanks for your post. My impression of that site largely matches your top 3. The site divides its time between selective reporting of local weather events, and persistent attempts to smear Dr. Hansen (and as they claim, “his buddy” Al Gore). They also include a good share of selective statistics and uncritically reporting any claim by any individual that falls in line with their goal of challenging the consensus view. There is a large media market for climate contrarianism and there are folks willing and eager to meet the demand. Some other themes, to add to yours:

    16. Grossly exaggerate every uncertainty and claim that we don’t know anything about global climate, yet fervently claim the human impact is non-existent or negligible, despite a giant body of evidence to the contrary.

    17. The scientific community falsifies their studies, in mass collaboration with their peers, to get grant money. Non-experts and non-published scientists know better. Real science is conducted within the blogosphere and from certain industry-funded organizations.

    18. The major scientific academies, the prestigious scientific journals and their statements on climate change, and the published studies are controlled by the elites. As the objective Senator Inhofe has shown via his press releases, many, if not most scientists, doubt the human impact.

    19. When global temperatures are cooler than the trend, ignore ENSO as a contributing factor.

    20. Global warming is a “religion” (explanation for any scientific consensus must be groupthink). Al Gore is the leader, which oddly implies that the scientific community follows him.

  35. 85
    Bill DeMott says:

    81–Benjiman P.

    I can add few more:

    16. We can’t trust research funded by scientists with grants, because they are only in it for the money. However, we also can’t trust scientist working for the government. (Perhaps we need to go back to the days when science was done by wealthy aristocrats who funded their own reseach as a hobby).

    17. Peer reviewed articles are only “opinion pieces” and can be dismissed as so much theory with no facts.

    18. One anecdotal observation by a blogger tops any number of replicated experiments in the scientific literature.

    19. The use of math and statistics detracts from the credibility of a scientific study.


  36. 86

    Welcome, Benjamin P.

    Nice list! (Summarizing well is not as easy as one might think–particularly while simultaneously shaking one’s head and rolling one’s eyes.)

  37. 87
    Doug Heiken says:

    The biosphere is one way to get some carbon out of the atmosphere in the short term. I like to say that if scientists and engineers were tasked with designing an efficient and inexpensive device for removing CO2 form the air, they could do no better than a tree. Trees are the ultimate “CCS” carbon capture and storage device.

    Here is a slide show clarifying many misconceptions about forests, logging, and carbon:
    (For full effect click “full” in the lower right.)

    Here is a more detailed foot-noted report on forests, carbon and climate change:

  38. 88
    Dean says:

    In the end, I don’t think that scientific illiteracy is much of an issue. Our lives are fundamentally affected in multiple ways by the technological offspring of science and most people haven’t a clue about but trust because it doesn’t undermine their world view and lifestyle.

    These things evolve culturally and generationally. Of course we don’t have time for generational change wrt this issue, but there are signs that the cultural change is in the offing – despite the lack of a clear climate-related “Pearl Harbor moment” that brought a cultural change in those days, and it is natural that denialists will have a reactionary response. It may well be a sign of their frustration at the cultural change they see coming. We can only hope so.

  39. 89
    Pekka Kostamo says:

    #83. I believe Lovelock recommens the biochar concept as the only viable solution. On the other hand, it would still require processing of huge amounts of materials, although the by-product syngas would be very valuable as a fuel.

    A derivative of this concept is to just dump masses of biomaterials to the oceans. Sunk below 1,5 km depth it would not decompose (so they say), but would be permanently stored. Minimum of processing: just collect, ship and dump. No technology development required, but some study on impacts. Could be an off-set for some indispensable uses of oil, maybe …

    “Dump before you pump” – permit conditions for oil wildcatters …

  40. 90
    Pekka Kostamo says:

    #66 Brian: NOAA has a nice world weather map showing the hot and cold spots, updated daily:

  41. 91
    Annabelle says:

    Sorry to post this to the wrong thread – but is there any reason why comments are closed on the Antarctica warming thread? There is a fascinating discussion on at Climate Audit on this very topic, which is casting serious doubt over the credibility of the Steig study. It would be nice to be able to ask a few questions.

    [Response: They were turned off last week since Eric is off to Antarctica. They are back on now. However, I wouldn’t get too excited about the current discussion (see figure S4 in the supplementary material). – gavin]

  42. 92
    dhogaza says:

    dhogaza (59), saying the people who gave him the information are SOBs is not exactly answering his question about that information

    I didn’t say they were SOBs, and yes, I did answer his question by pointing out that it is MISinformation, not information, and suggesting he ease his learning task by sticking to scientific sources of information. I would agree with you that those who try to intentionally confuse and mislead people by posting MISinformation are SOBs, but I didn’t say that.

    Same advice would apply to you, come to think of it …

  43. 93
    Mark says:

    re 89: problem is, plants aren’t pure carbon. So we need a proportionate amount of whatever else goes into lignin et al that isn’t brought back from the char process to be made artificially available.

    May be easier said than done.

    Is Lovelock a biologist?

  44. 94

    I like to say that if scientists and engineers were tasked with designing an efficient and inexpensive device for removing CO2 form the air, they could do no better than a tree.

    Then you like being wrong. Mineral carbonation is much more permanent and does not require well-sunlit land. Abundant alkaline earth silicate minerals, not the sun, provide the CO2 capture energy.

    (How fire can be domesticated)

  45. 95

    Benjamin P (81),

    Nr 14 on your list caught my eye: “Consensus is bad (something we can all agree on)”

    Of course the presence of a consensus doesn’t prove anything, but I think there’s more nuance to it:

    The so-called consensus grew in response to the growing body of evidence and the application of scientific standards (see eg this presentation by Oreskes: As such, the existence of a strong consensus is entirely relevant. Moreover, a consensus of risk amongst experts (‘BAU ain’t good’) should not lightly be ignored.

    I liked your list though.

  46. 96

    Re #94 Cowan,
    Why do we have a problem if the “abundant” silicate minerals will capture CO2?

    While we have a chemist to talk to, aren’t sea shells calcium carbonate? They last a long time.

    Also Re #49 Greisch,
    I looked at the linked site and find this possibly very interesting, important, and dangerous. Maybe the danger is manageable. The site says the waste is low grade, potentially processable, and “about the size of a softball.”

    Good or bad I do not yet know, but surely there should be some serious attention given to this thing that seems to be happening.

  47. 97
    Hank Roberts says:

    > trees
    > silicate
    > problem

    Biogeochemical cycling, q.v.
    Rate of change of rate of change.
    Calculus required.

  48. 98
    ike solem says:

    Basically, the problem with long-term carbon cycle and climate forecasts is that you don’t really know the biosphere-ecosystem response to higher temperatures, nor do you really know how ocean circulation patterns are going to change – and if you are going to talk about the carbon cycle, you really have to include the nitrogen cycle as well as the role of iron and other nutrients.

    The idea of dumping iron in oceans to fertilize them in order to increase phytoplankton growth and permanently draw down atmospheric CO2 is ludicrous – imagine if someone proposed doing that in lakes and rivers – which is what phosphate fertilizers did in the past (in conjunction with heavy metals, which killed off herbivores). If you wanted to do it on a global scale, you’d cause massive ocean hypoxia – in fact, we are already fertilizing the Gulf of Mexico with massive amounts of agricultural nutrients, leading to giant algal blooms, ocean hypoxia and the die-off of fisheries – yet some would have you believe that this is an effective method of removing carbon from the atmosphere.

    There is really only one way to remove CO2 from the atmosphere, and that is to convert it to a solid form of carbon and bury it. There’s mineral weathering, and there is burial of biomass. In fact, the most likely proposal so far for carbon removal is to bury biomass in oceanic trenches and anoxic basins where it is unlikely to ever get digested back to CO2.

    The basic notion is this:

    ScienceDaily (Jan. 29, 2009)”Making bales with 30 percent of global crop residues – the stalks and such left after harvesting – and then sinking the bales into the deep ocean could reduce the build up of global carbon dioxide in the atmosphere by up to 15 percent a year, according to just published calculations.”

    That assumes the complete elimination of fossil fuel combustion, however.
    Notice that the efficiency of burial is estimated around 90%, compared with about 25% for the next most efficient method, biochar-based soil amendments (which, however, are very good for depleted industrial soils).

    Eliminating fossil fuels is a much more challenging job, as replacement power sources must be devised. Along those lines, Nature just announced the formation of the International Renewable Energy Agency, which so far the U.S. and Britain have been refusing to support – now, why wouldn’t the U.S. or Britain be interested in renewable energy?

    Notably missing from the current list are the United States, the United Kingdom, China, India and Brazil. The administration of former US President George W. Bush did not support the proposal, but Barack Obama’s crew is thought to be more amenable to the idea. Whether and when these and other countries will join is an open question, but one thing is clear: the broader the support, the more potential there is for IRENA to accomplish its goals. [India has now agreed to support it]

  49. 99
    Benjamin P. says:

    Bart Verheggen (91)

    My comment on consensus is totally tongue-in-cheek.

    They are always talking about consensus over at WUWT, and in a sense, there is a consensus that consensus is bad!

    So I was just having fun with that bit of irony.

  50. 100
    Peter McEvoy says:

    Excellent post. Let’s hope this heats up the fire under some peoples pants to actually take action and reduce their impact!