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Unforced Variations: Aug 2011

Filed under: — group @ 2 August 2011


475 Responses to “Unforced Variations: Aug 2011”

  1. 51
    Snapple says:

    [edit - way too far OT, sorry]

  2. 52
    Snapple says:

    Sorry–it’s back up. Lucky I didn’t get nasty!

  3. 53
  4. 54
    Paul S says:

    From Robert Murphy’s post 45:

    “Mother Nature intervened and CO2 after the turn of the century continued to increase, in fact if anything, slightly faster, but global temperature didn’t. If anything, it decreased in the first decade of the 21st century.”

    Er, doesn’t this contradict his proposition that observed CO2 increases have been driven by temperature increases?

  5. 55
    grypo says:

    This seems to be the crux of Salby’s argument:

    “The trend in CO2 derives from a hysteresis in its
    annual cycle: More is emitted during half of the
    year than is absorbed during the other half. The
    residual, which accumulates to fo rm the trend,
    provides a record of net emission. It is shown
    to track the satellite record of global -mean
    temperature, which fl uctuates b etween years.
    Temperature changes of 0.5 – 1.0 K are attended
    by modulations o f C O2 emission as large as
    100%. Much the same dependence is exhibited
    by isotopic composition. The temperature
    dependence o f CO2 parallels that of water vapor,
    the dominant greenhouse gas. Such dependence
    governs CO2 emission for temperature changes
    that are clearly of different origin, including the
    eruption of Pinatubo and the 1997-1998 El Nino.”

    [Response: Yes. Having now listened to the podcast, I thnk he has done a regression of growth rate to temperature (and soil moisture) over the recent period. The sensitivity he then derives is projected back using the 0.8 deg C warming over the 20th C. However, this is ludicrous - the sensitivity in the recent period can't be more than say, 1 ppmv per 0.1 deg C. Projected back you would have say a 10 ppmv (max) change over the 20th C. Paleo-climate constraints demonstrate that CC feedback even on really long time scales is not more than 100 ppmv/6 deg C (i.e. 16 ppmv/deg C), and over shorter time periods (i.e. Frank et al, 2010) it is more like 10 ppmv/deg C. Salby's sensitivity appears to be 10 times too large. Someone might want to have a look at the data and redo the regressions, but the physics is screwy. - gavin]

  6. 56

    Curry highlight’s Salby’s Fundamentals of Atmospheric Physics as “a popular introductory graduate text”. Don’t know if that’s true, but it’s interesting to see who the “Senior Editor” is. One Roger Pielke Sr.

    She also points to a synopsis of some talk Salby was to deliver. With nothing more than that, it’s hard to say what his points are, but there do appear to be some howlers. For instance, in the concluding paragraph he states:
    “The satellite record of global temperature, in tandem with the instrumental record of CO2, provides a population of climate perturbations. Of natural origin, they establish the climate sensitivity of CO2 with respect to changes of temperature. The climate sensitivity enables the natural component of CO2 to be evaluated.”

    So, in his definition, “climate sensitivity” is a measure of the response of CO2 to temperature. That, he implies, is determined using just the satellite temperature record and corresponding atmospheric CO2 record. And then you use that derived “climate sensitivity” to determine the natural contribution of CO2????? Wha???

  7. 57
    J says:

    On her own blog, Judy writes: Gavin’s argument makes the fallacy that all temperature change is externally forced. If the temperature change is caused by natural internal variability, then this argument is not useful.

    That seems inexplicably wrong to me. Salby (and Gavin) are discussing a model under which the observed variation in atmospheric CO2 is primarily determined by temperature change. Why would it matter if that temperature change was from internal variability vs external forcing? I don’t get it.

    [Response: You are correct. This has nothing whatsoever to do with attribution of the temperature rise. The response of the CC to temperature is a specific thing - and it doesn't matter if it is originally driven by Milankovitch and ice sheets (over the ice age cycle), solar and volcanic activity over the pre-industrial, or by human activity/martian fairies/the PDO or whatever today. ENSO is an internal source of temperature changes on short time scales, and Pinatubo is an external source of temperature change over a short time period - both are included in any modern period regression such as Salby must have used. And the sensitivity of the carbon cycle to such changes is noticeable, but small and nothing like enough to explain the 20th C change. But even without thinking about this that deeply at all, it is obvious that Salby is wrong - we have put more than twice as much CO2 into the air as has actually accumulated over the last 100 years. To posit that the rise is not anthropogenic implies finding sinks that have totally taken up the anthropogenic CO2 *and* new sources that have put half of it back again. Meanwhile, all the actual reservoirs have more carbon than they had previously. Furthermore, the 13C and 14C data (up until the bomb peak) support a predominantly fossil fuel source. And the O2/N2 levels are dropping at the rate expected (given that we are burning C, and taking O2 from the air). The idea that a poorly performed regression undermines all this is ludicrous. - gavin]

  8. 58
    SecularAnimist says:

    J wrote: “I don’t get it.”

    That seems to be a very common reaction to Curry’s pronouncements, many of which, as far as I can tell not being a climate scientist myself, make little sense.

    Not to mention that her accusation that Gavin has asserted that “all temperature change is externally forced” is clearly not true.

  9. 59
    M says:

    “But even without thinking about this that deeply at all, it is obvious that Salby is wrong – we have put more than twice as much CO2 into the air as has actually accumulated over the last 100 years.”

    I think – and they are obviously wrong about it – that the mental argument some of these people make is that CO2 is like water vapor, eg, that it very rapidly comes into equilibrium with the global temperature. With water, if we dug up the Ogallala aquifer and boiled it into the atmosphere, and then we measured an increase in global atmospheric water vapor that was half the size of the quantity we boiled, we could still conclude that the water vapor increase was _not_ due to having boiled the aquifer. That’s because the amount of water vapor in the global atmosphere is roughly determined by global temperatures, and any excess that’s added will quickly rain out and add to the oceans.

    Of course, CO2 is not water vapor, and we knew this 50 years ago with Bolin & Erikkson’s seminal paper.

    If I had a few weeks of free time, and some better programming chops, I’d be really tempted to build a bare-bones web-version of a carbon cycle model, with the minimum complexity necessary to do a reasonable job of matching C12/C13/C14 ratios, the annual cycle, and some of the interannual variability due to temperature wiggles. It would have to include oceanic carbonate chemistry at a minimum, of course (something that all these out-of-field modelers seem to ignore). Then, whenever anyone tried to argue that their analysis of isotope ratios showed that the CO2 rise was natural, we could point them at the simple model and say, “use your method and analyze this model. If your analysis determines that the CO2 rise in the model is completely natural, then perhaps you should rethink your methodology”.

    (effectively the same approach to take for people who claim that a simple analysis shows that CS is small based on global temperature data, but if they were to apply the same analysis to a model in the CMIP archive, their method would also come up with a CS that is much smaller than the CS we know that the model has)

  10. 60
    tamino says:

    … or by human activity/martian fairies/the PDO or whatever today …

    You forgot the Leprechauns! I’m sick to death of people ignoring the Atlantic Multidecadal Leprechauns.

  11. 61
    Meow says:

    What does Salby say happens to the carbon from the ~6 GT coal, the ~26 Gbbl oil, and the ~130 T ft^3 natural gas that we mine each year?


  12. 62
    ozajh says:

    Hank Roberts #53,

    Andrew Bolt has long been VoldeMurdoch’s most strident attack dog here in Australia. His recent spate of Climate Denial articles/blogs is IMHO a direct result of the recently introduced Carbon Tax.

  13. 63
    John Mashey says:

    People may find the kerfuffle @ Chronicle of Higher Education to be of interest, see this by me and Rob Coleman.
    Rob is a very good guy:
    Professor of Chemistry @ Ohio State and chairs OSU academic misconduct committee


    Folks like Tom Fuller have already showed up, but if anyone posts over there, please be polite, even if it seems hard.

  14. 64
    One Anonymous Bloke says:

    A 10,000-Year Record of Arctic Ocean Sea-Ice Variability—View from the Beach being quoted by the BBC. The BBC article explains:

    The idea of an Arctic tipping point has been highlighted by many scientists in recent years. They have argued that when enough ice is lost it could cause a runaway effect with disastrous consequences. “I don’t say that our current worries are not justified, but I think that there are factors which will work to delay the action in relation to some of the models that have been in the media. I think the effect of temperature and global warming may cause a change in the general wind systems which maybe will delay the effects of the rapidly rising temperatures a little bit.”

    Dr Svend Funder

    The quote at the same seems vague. Is there anything at all in the paper or elsewhere to support it?

    [Response: Actually, I think the 'runaway affect with dire consequences' is a strawman. There have been lots of papers showing that there isn't any such thing - and indeed, you wouldn't expect it based on the ~5 yr timescales in the sea ice pack - there isn't enough memory in the ice to kick you into a new state. There is lots of interesting non-linearity, and nothing related to this means that sea ice is going to recover any time soon (it certainly won't). The status of the summer sea ice in the Early Holocene is very interesting though, since there are indications that it was less than today (raised beaches in N. Greenland that are still frozen solid). But that occurred with substantially more insolation than we have today too. - gavin]

  15. 65
    Thomas says:

    A couple of potentially interesting papaers:
    Breeding Crops With Deeper Roots Could ‘Slash CO2 Levels

    Ancient Tides Quite Different from Today — Some Dramatically Higher, Some Lower
    Sorry they are just sciencedaily, I don’t have accounts so probably couldn’t see the originals.

    The first one proposes that we breed crops to have deeper roots, as this could significantly increase soil carbon content over a period of time.

    The second one shows evidence that regional tidal ranges have changed significantly over the past few thousand years. If the little bit of sea level rise we’ve had over this period can perturn tidal ranges this strongly, I can only imagine what sort of changes we may see this (and next) century.

  16. 66
    barry says:

    After reading the interview of Jeff Gleason provided upthread, (as well as the Monnett interview and the 2005 observational note) it is painfully obvious that the investigators were trying to discredit the 2005 polar bear paper earlier this year, and that when that failed they shifted to another line of inquiry to discredit Monnett.

    Monnett is still suspended. PEER seems to be on the case, but is there anything else that can be done? The evidence of political interference is so clear that the Dep. of the Interior should be investigated. If I were a US citizen I would start a petition or something. Monnett’s life has been turned upside down and his reputation muddied because work interferes with policy objectives.

    Here are all the relevant docs I know of:

    2005 observational note

    Transcript of Jeffrey Gleason’s interview in January 2011

    Transcript of Charles Monnett’s interview

    July 29 2011 letter from investigating agent Eric May finally stating the allegations – which are completely different to the allegations they made in the interviews. The only common link is polar bears

    Memos from the Department of the Interior in 2007 ordering scientists traveling abroad not to talk about polar bears, sea ice, or climate change

  17. 67
    Edward Greisch says:

    38 Alistair Connor: Thanks. Google scholar for “identity-protective cognition” gets about 60 articles, a lot. One of them,

    has an abstract that includes “The ‘cultural cognition of risk’ refers to the tendency of individuals to form risk perceptions that are congenial to their values.”

    As scientists, we do it the other way around. Truth as revealed by experiment is our basic value. But we do form risk perceptions that are mathematically related to the numbers that we get from experimental measurements. AH HA! The difference is in where the values come from. And whether those values are instinctive or numerical. So all we have to do is convince them that our values are better than their values.

    39 Ray Ladbury: Is “negatively-sloped learning curve” the same as a negative IQ? I have noticed that sort of thing.

  18. 68
    One Anonymous Bloke says:

    Re: Prof. Schmidt’s response to my #64. Thank you. I was also impressed by “may cause a change in the general wind systems which maybe will delay the effects…” My wild guess is that those “mays” and “maybes” aren’t constrained by very much either. Perhaps some ice dragons will breathe our way or something.

  19. 69
    Ron R. says:

    Grolar bears, a sign of the coming genetic dilution and/or eventual extinction of the polar bear.

    Sad. Besides being beautiful animals, polar bears are a wonderful evidence for evolution.

    Oh well, I suppose that at least the Creationists will be pleased.

  20. 70

    Ecofys/IEA GHG report on bio-CCS: Large global potential for negative CO2 emissions through biomass linked with carbon dioxide capture and storage

  21. 71
    Didactylos says:

    How stupid of me to think the scientific witch-hunts would be over with the departure of Bush. He left plenty of oil-minded anti-science morons behind when he went.

    It’s rather regrettable that Monnett was so forthright at the end of his previous (hilarious!) interview. I’ve seen this sort of thing before, when someone becomes an embarrassment (or, worst of all, is embarrassing the bosses with the inconvenient truth). The Powers That Be just sit there and make life intolerable for their victim, until they can come up with a petty excuse to use as a pretext to boot their victim out.

    Frankly, I’m surprised it took them so long.

  22. 72
    Didactylos says:

    With respect to “an Arctic tipping point”….

    My understanding was that the tipping point in question is a phenomenon observed in individual model runs where sea ice collapses suddenly and does not recover. I’m not aware of any significant impact of this beyond the Arctic. Obviously it will alter albedo slightly. But this tipping point isn’t something that shows up in the ensemble mean – the timing of it isn’t predictable.

    But… these results must have been derived from the old sea ice models that are already underestimating sea ice loss. We must have better models now. Am I out of date (or just plain wrong)?

  23. 73
    Kevin C says:

    Some econometrics professors take on the problem of calculating the relative contribution of GHG warming and aerosol cooling to recent temperature trends, here.

    The statistics are way over my head. As a lay person there are a couple of points about the climate science that bother me. However if they are right, or if any problems with the method can be fixed, this could be a very significant contribution.

  24. 74
    J says:

    I’ve just attempted to post this very lengthy comment in the “Salby” thread over at Judith Curry’s blog.

    It doesn’t seem to have shown up. My first guess is that due to the length and the presence of external links it was flagged for moderation. If that’s not the case, my second guess is that there was some glitch in the posting process and it vanished into the ether.

    In any case, if you don’t mind I’d like to copy it here, since it may either not show up at Judy’s, or might be missed there in the flurry of comments. Feedback is welcome, and I hope I haven’t misstated anything or misrepresented Gavin’s remarks.


    The possibility that natural variability explains the century-scale observed rise in atmospheric CO2 can easily be dismissed based on simple accounting (anthropogenic emissions are larger than the rise itself, and thus account for over 100% of the observed rise).

    Aside from that, however, Gavin Schmidt makes what seems to be a very good point. As I understand it, Salby’s claim is that the observed rise in CO2 is primarily the result of a natural flux that is dependent on global temperature; a warming ocean/biosphere would give off CO2 to the atmosphere, while cooling would produce the opposite effect.

    It’s not news to anyone who studies the carbon cycle that the flux of CO2 between the atmosphere and the ocean/biosphere is affected by ENSO-style short term variations in temperature (see, e.g., Bacastow and Keeling 1981, or AR4 WG1 Section But the magnitude of these variations are small compared to the century-scale rise in atmospheric CO2.

    This brings us to Gavin Schmidt’s comment, written at RealClimate and quoted by Chris Colose earlier in this thread. Gavin points out that if Salby’s model truly explained most or all of the 100 ppm observed rise in CO2 based on the 0.8 C rise in global temperature over the past century, that would imply a massive sensitivity of the CO2 flux to global temperatures. Looking at the Keeling curve, or any of the other long-term atmospheric CO2 data sets, we see that interannual variability in temperature only produces relatively small fluctuations in the rate of increase of CO2 in the atmosphere, as discussed in IPCC AR4. The increase itself does not flip to a decrease during cool years. Perhaps more problematically, such a model would imply that the large temperature changes associated with the glacial/interglacial cycle would produce immense swings in CO2 (on the order of 500 – 1000 ppm). That is an order of magnitude larger than the observed CO2 fluctuations in the ice cores.

    Dr Curry, who I’m sure is very busy and may not have had time to dive into this in detail, responded to Gavin’s comment with the following:


    With all due respect, I don’t think that’s correct. Recall the directionality of Salby’s model: temperature change drives the CO2 flux, not vice versa. It does not matter whether the temperature change was externally forced or not — the CO2 flux is a direct response to the temperature change. How would the atmospheric CO2 flux know that it is supposed to respond very strongly to temperature changes that are caused by the “right” forcings (century-scale internal variability) but respond an order of magnitude less strongly to temperature changes that are caused by the “wrong” forcings (ENSO, Milankovich cycles, etc).

    I’ve asked Gavin about this, and he appears to confirm my understanding. I’m guessing that Dr Curry’s response quoted above was written in haste (I know she’s very busy!) but if she still believes that differences in the source of a temperature forcing would rescue Salby’s model from this apparent contradiction, I’d very much appreciate hearing more about it.

    This comment has already gotten too long, but I’d like to point out that based on what we know so far, it looks very much as if Salby is making the same mistake that McLean made (in attributing the temperature rise to ENSO) and, even more similarly, that Mr Lon Hocker made in a post at WUWT in which he made virtually the identical argument to this one (temperature changes explain the atmospheric CO2 trend). That error consists of [1] detrending the dependent variable (global temperature, in McLean’s case; CO2 for Salby and Hocker); [2] discovering that the annual rate of change in that dependent variable is closely correlated with some independent variable (ENSO for McLean; global temperatures for Salby and Hocker); and then [3] mistakenly asserting that the independent variable explains the observed trend, when it actually explains small fluctuations around that trend.

    Salby’s idea here really does appear to be following more or less exactly in the footsteps of Lon Hocker’s post at WUWT. That post was discussed in a great deal of detail over at Skeptical Science, and I’d strongly encourage anyone who thinks Salby might be onto something to go read John Cook’s dissection of Hocker’s post.

    To sum up, the evidence that the observed rise in CO2 is anthropogenic is really overwhelming. For those who are determined to maintain a contrarian position on AGW, there are other much better grounds on which to base that position (maybe climate sensitivity is low, or maybe the impacts of GW will be on balance positive, or maybe the impacts will be negative but the costs of mitigation would be higher than the benefits). Enthusiastically grasping at claims that the observed CO2 rise might not be anthropogenic in origin drastically reduces one’s credibility.

    Once again, apologies for the length of this comment.

  25. 75
    Pete Dunkelberg says:

    Deciphering J’s report from planet Inverth, that planet is being heated by heat demons and the heat provokes the inhabitants to burn more fossil fuels. The coincidence of these two things leads some confused inhabitants to make the wrong inference, but they are easily shouted down by the air conditioning loving majority.

  26. 76
    TimTheToolMan says:

    It seems to me that if our warming earth meant that CO2 levels should be rising to follow (as has been seen historically from ice cores) then the atmosphere could be out of equilibrium with CO2. We could be redressing that imbalance “immediately” by putting it there ourselves hence giving the appearance of much higher sensitivity.

    [Response: Huh?]

  27. 77
    J says:

    My long comment (see above) has now appeared at Judith’s site. I’m glad it was just held up in moderation, and not lost.

    TimTheToolMan, keep in mind that the past century’s CO2 increase (on the order of 100 ppmv) is roughly equivalent to the range of variation associated with the full glacial/interglacial cycle (also on the order of 100 ppmv).

    If the CO2 rise were entirely natural, and a function of temperature, why would a temperature rise of 8C produce the same response as a rise of 0.8C?

  28. 78
    J says:

    tamino wrote: You forgot the Leprechauns! I’m sick to death of people ignoring the Atlantic Multidecadal Leprechauns.

    Modesty apparently keeps Tamino from linking back to his own site, but that discussion (the Atlantic Multidecadal Leprechaun Oscillation thread) was one of the most hilarious things I’ve read in the past year. Check it out. Really.

  29. 79
    caerbannog says:

    Didactylos 5 Aug 2011 @ 6:10 AM:


    Special Agent Eric May’s interrogation of Dr. Monnett brings back fond memories of Inspector Clouseau busting that organ-grinder and his minkey for operating without a “lisconse”.

  30. 80
    SecularAnimist says:

    Salby’s lecture is already being proclaimed by Ditto-Head deniers on blogs everywhere as the latest “refutation” of the anthropogenic global warming “hoax”.

  31. 81
    Agnostic says:

    Having followed the global warming/climate change debate and science for quite a while, I’m always interested to see how the two sides of the debate treat information that is potentially harmful to their position.

    I listenened to Salby’s talk as well, and at one point he says that if the IPCC had this information prior to their last report, they could not have reached the conclusions they did (among the other quotes ably reposted in this thread).

    To a lay person with an open mind, that’s a powerful statement coming from someone who is (by all accounts) a respected scientist. And all the cheering happening on the skeptic’s blogs right now is mirrored by the out of hand dismissals (even from Gavin!) on this site.

    For rationality to prevail, all those involved in a debate must ask the question ‘what new information might cause me to change my position?’ At this point all we have is a podcast from a talk, with a couple of papers forthcoming. But I’ve heard no one on this thread say “well, if he’s right, I guess that changes things.”

    I could be wrong (and I’d be the first to admit it), but something tells me unless Salby made some kind of fundamental error (and he says he sat on his results for a year in order to prevent that) and his results are in error, that this is a big deal. If science has inverted the relationship between CO2 and temp, then we’re going to have to re-think a number of things.

    I’ll be interested to see how this plays out in the hard science journals in the coming years.

    [Response: To a large degree being a scientist is all about correctly judging (most of the time) what is and what is not a fruitful line of research. Statistical reworkings of data has been available for years and which are well explained by our standard understanding, do not fall into the category of something that is going radically going to change our understanding. It is far more likely that someone a little out of their ifield, who isn't up to date, and has made the (very common) mistake of over-interpreting their statistics. The question to be asked in such circumstances is what would be implied if the conclusion was correct? In this case, it would imply radically bigger changes of co2 during the ice ages, some completely unknown source of carbon that dominatea all others. This would be extraordinary, and would require far more than a few correlations to demonstrate to anyone else's satisfaction. I very much doubt you will see this 'play out' in the literature over the next few years. - gavin]

  32. 82
    John N-G says:

    I was lucky enough to attend Murray Salby’s talk at the IUGG conference in Melbourne. The thesis is not quite so simple as a correlation between CO2 rise and short-term temperature variations, because he found corroborating evidence in the change of CO2 slope over time. This made the argument not so easy to dismiss out of hand, although Salby was extremely careful not to draw any conclusions in his public presentation.

    It was quite good sport to play “spot the flaw” in real time. Fortunately, the talk was the last of the session, and both Alan Plumb and myself chatted with him right afterwards. Aside from whether a statistical argument makes physical sense, it also must hold water statistically by being applicable beyond the time frame of model development. In discussing what his model would mean for past variations of temperature and CO2, it eventually became clear that he believed all paleoclimate data that supported his statistical analysis and disregarded all paleoclimate data that countered his statistical analysis, even though the latter collection was much larger than the former.

    Eventually I realized that if 0.8 C of warming is sufficient to produce an increase of 120ppb CO2, as Salby asserted, then the converse would also have to be true. During the last glacial maximum, when global temperatures were indisputably several degrees cooler than today, the atmospheric CO2 concentration must have been negative.

    That was enough for me.

    ReCaptcha oracle: tierra deporte (spanish for “Earth sport”)

  33. 83
    Chris Colose says:

    John N-G,

    I think you are right. The CO2 feedback sensitivity to temperature is O(10 ppm/ C) and there is a multitude of paleoclimatic events in the past that would pick up on something off by a factor of 10. Just as importantly, the oceans and biosphere are acting as a sink for the CO2, in collaboration for isotopic and O2 decline signatures that provide a robust framework for the origin of the excess CO2.

  34. 84
    S. Molnar says:

    I can’t help noticing a pattern of commenters here and elsewhere who claim to be long-time followers of the climate science global warming debate apparently failing to realize that there are many climate science global warming debates, non of which are what they appear to think is “the” debate. I generally stop reading after the first sentence these days (which, of course, makes me close-minded).

  35. 85
    chris says:

    Agnostic – 5 Aug 2011 @ 12:56 PM

    There’s something a little sad about your post. Someone in a supposed position of knowledge (Selby) says some astonishingly ignorant things: statements that are demonstrably incompatible with what we know. He insinuates that the warming of the last ~130 years (0.8 oC) is responsible for the rise in atmospheric CO2 (118 ppm) even ‘though it’s obvious that the [CO2] response to surface temperature change must be an order of magnitude smaller than this (the 5000 year transition from glacial to current (Holocene) interglacial produced around 90 ppm of [CO2] from an ~ 6 oC of global temperature rise, indicating that even allowing for [CO2] to come to equilibrium with surface temperature the [CO2] response can’t be greater than around 16 ppm per oC of surface warming).

    Selby states that he doesn’t believe the ice core [CO2] data. Brilliant! If you categorically dismiss what we know out of hand then any old rubbish can be pursued.

    It’s obvious that increased [CO2] can’t be coming out of the oceans in response to surface warming. The ocean pH is decreasing – so CO2 has to be going into the oceans. The astonishingly rapid rise in [CO2] of the last 50 years is very clearly associated with a very easily measured reduction in 13C/12C ratio indicating a dominant source in 13C-depleted CO2 (i.e. biogenic; aka fossil fuel).

    This is so obvious to be a no-brainer. Informed individuals would be remiss not to point this out…….and yet those that benefit from cheating Joe Public have learned that any old garbage will do since quite a lot of people will find it useful and will likely spread it all over the internet. And even though this junk is spread in order to support agendas that are likely to diminish Joe Public’s qualiy of life, they’ve managed to sucker a good few Joe Publics into accepting the rubbish – just as they did when the science on smoking/respiratory disease and lung cancer was misrepresented…and aspirin taking in children/Reyes syndrome and so on…and on..

  36. 86
    TimTheToolMan says:

    Gavin writes “Paleo-climate constraints demonstrate that CC feedback even on really long time scales is not more than 100 ppmv/6 deg C (i.e. 16 ppmv/deg C), and over shorter time periods (i.e. Frank et al, 2010) it is more like 10 ppmv/deg C. Salby’s sensitivity appears to be 10 times too large.”

    You’re comparing a cooling phase with a warming one. There are also considerations on what life does (with CO2) during these times. Its entirely possible that large amounts of CO2 are released (and sequestered) during cooling phases.

    So in a nutshell, the planet cools, life declines and releases the carbon as CO2 which is sequestered into the ocean. The planet warms and the ocean releases large amounts of CO2 which life grabs.

    Hence more CO2 is potentially sequestered than your simple “look at what is in the atmosphere and assume thats what gets sequestered” point of view.

    The same argument goes in reverse except in our case by emitting CO2 ourselves we’re ensuring that the earth is always in equilibrium with its Temp/Life balance/Atmospheric CO2 level. And then some probably.

    Its all about thinking through the implications of CO2 levels being driven by the climate rather than the other way around. If you cant do that or aren’t willing to properly explore that, then as Salby also says, you’re no longer acting like a scientist. You’ve become an advocate for AGW.

    So far many people in this thread have written off this research without even having seen it!

    [Response: Yup. Just as I have written off research demonstrating the non-existence of gravity, the validity of astrology, evidence that consuming plutonium is good for you, or the discovery of the fabled 'counterEarth' on the other side of the sun, I have not bothered to look any farther than Salby's podcast, which provided enough information to tell me not to look further. Being a scientist means, among other things, not wasting one's time reading every random bit of 'research' that pops up in the blogosphere making claims to have overturned well established facts. I could be wrong of course, but until I hear something at least vaguely believable, I'll not be paying much attention to this one. --eric]

  37. 87
    Steve Metzler says:

    Chris C at #83 puts it all so succinctly, as did Gavin a few times before in this thread. Salby seems to have ‘gone emeritus’ a few years before his time, if the press photo is anything to go by (that is, if it’s current). This will be the denier’s “nail in the coffin for AGW” this month, anyway. Cynically looking forward to what will come along to top it next month, when Salby’s physically baseless claims fizzle out like the damp squib that they inevitably are.

    The tragedy of the commons will be mankind’s downfall. Meh. Had more to say, but best leave it there.

  38. 88
    Russell says:





  39. 89
    J says:

    Agnostic, I don’t see the need for all that agonizing.

    I don’t know whether or not there will be anything of interest in Salby’s as-yet unseen paper, but I’m pretty confident it’s not going to suddenly reveal that we’ve “inverted the relationship between CO2 and temperature”.

    Nobody goes through life constantly thinking “What if Maxwell’s work on electromagnetism turns out to be wrong and all our electrical appliances suddenly stop working?”

    In principle, one could be wrong about all kinds of stuff. In practice, it’s highly unlikely that the railway station you’re passing on your way to work will suddenly turn out to be a giant octopus that was merely disguised as a railway station. You’re much better off using your mental energy for more important problems.

    For stuff that’s uncertain, debatable, or poorly known, you should of course always consider the possibility that you’re wrong. But it’s not always easy for an outsider to know what parts of a scientific field fall into the category of “stuff I should be continually questioning myself about” versus the category of “stuff I can safely assume is true until smacked in the head by evidence otherwise”.

    So, Agnostic, is there a lesson that should be drawn from this Salby episode? I’d say that the most obvious one is how many “contrarians” — people who probably like to think of themselves as hardnosed “skeptics” — have unskeptically jumped on the bandwagon being driven by Salby’s popularizers (Jo Nova, Andrew Bolt, etc.) Nobody’s seen this paper yet. Most papers that are promoted as dramatically overturning a huge body of existing knowledge turn out to be flawed. Any real skeptic would be extremely dubious about the claims for Salby’s paper.

  40. 90
    Susan Anderson says:

    Found on Tenney Naumer’s blog – really shocking that some of the best reporters around were attacked. Hope this goes viral, and I don’t apologize this time:

  41. 91
    Pete Dunkelberg says:

    J wins the night!

  42. 92
    Tom Keen says:

    Has anyone read this recent article by James Hansen? It’s certainly a conversation starter.

    Baby Lauren and the Kool-Aid

    An interesting quote that goes to the heart of the essay:

    The merchants [of doubt] play a role, to be sure, a sordid one, but they are not the main obstacle to solution of human-made climate change. The bigger problem is that people who accept the reality of climate change are not proposing actions that would work.

    I’d be interested in reading people’s reactions to it.

  43. 93
  44. 94
    Chris G says:

    Some thoughts:

    Have to agree with Gavin that the debate over the possibility of a Venus-like runaway is a bit of a distraction. Somewhat interesting, but that argument is kind of moot if a ‘minor’ runaway that pushes the planet even 8 K is enough to end modern civilization.

    All runaways would plateau off eventually; I don’t think there is any physical process that would not be overcome by the fourth power factor of energy emitted in Stefan-Boltzmann. Heck, even stars, which undergo an astronomical positive feedback once fusion is triggered, level off in temperature at some point.

    Runaways and tipping points go hand in hand. There is more than one threshold or tipping point. Arctic ice has it’s own, permafrost another, the WAIS another. I think the biggest ‘if’ is the question of how many of these dominoes can push the planet to another one. Does losing the PIG mean that we also lose Thwaites, and thence most of the WAIS in time? Would losing summer Arctic ice help push us past a major clathrate release, or merely reinforce permafrost methane release? Would an increase in methane release from not-so permafrost subsequently trigger some clathrate releases? It is a multi-headed beast we are poking.

    I would be surprised if there were not attraction points in the earth climate system. If you add non-linear functions together, you are bound to get local minima and/or relatively level plateaus.

  45. 95
    Edward Greisch says:

    81 Agnostic: There is no real debate. It is an entirely phony debate. What you need is enough education or training in science to be able to detect nonsense. The thing for a lay person with an open mind to do is go back to school. I know that that is difficult. It takes money, time and hard work. Your high school should have taught you a lot more than it did, but you should have taken more science and math in high school. The same goes for college if you went to college. And yes, everybody should learn enough science to know that the debate is phony. Salby isn’t fooling any scientists.

    For rationality to prevail, fossil fuel companies have to quit sponsoring propaganda or you have to ignore the propaganda. The real debate has been over since 1988 at the latest. Read “Climate Cover-Up” by James Hoggan and “Merchants of Doubt” by Oreskes and Conway. You should have picked those 2 books up from my previous post on this topic.

    For rationality to prevail, people have to be more rational. See previous posts. There are psychological barriers you may have to overcome to become a scientist. At the least, you have to understand that truth comes from doing scientific experiments, not from debate, ancient books, voting, consensus, organizations, people, authority or other unscientific sources. So you must take laboratory courses. You must learn to never believe any person, including yourself. A “powerful statement coming from someone” is something that you have to view as wrong until proven right. Physics majors in college never believe anything their professors say until there is no other possibility. That is the attitude you must have.

  46. 96

    There is a possible visual proof about the effects of CO2, if I recall well, Raypierre estimated that the largest CO2 heat signature on a temperature Upper profile
    would be at the mid to lower atmosphere. If so there would be a larger temperature inversion there which would technically generate a lower stronger near surface one. In the Arctic this is seen as greater brightness during twilight, since sunlight from the South is carried much further North, particularly at about the winter solstice. On my webpage I call this effect the Y-V ulluq Q. Given a warming planet there should be a period of time when the high arctic experiences unusual brightness carried by temperature interfaces during long night twilights, or highly unusual sunrise location shifts mainly in January February, when the sun is still very low on the horizon. When the sun gets higher in the sky during spring the opposite occurs because warmer sun rays essentially demolish surface inversions. This effect has been observed throughout the high Arctic by independent witnesses, especially by highly sensitive to twilight brightness hunters. And so the Curry’s and the like would have to explain why twilight is brighter because CO2 has very little impact on temperature. There is something affecting twilight, and they of course offer no plausible alternative given that they discard CO2. The intuitive explanation, as a pre-emption to a possible rebuttal would be that the sea ice is thinner with more leads, generating stronger inversions, that is correct, its been filmed and observed, but something is melting the ice at a very fast and steady pace, it took decades to melt multi-year ice, so the effect is not linear… I wonder if something else, present for decades may have affected Arctic sea ice. Lets be clear, there is no other replacing element offered by the contrarians, aside from innuendos readily not observed…

  47. 97
    Icarus says:

    I see a lot of articles and papers and blog discussions on positive feedbacks from ice albedo reduction, permafrost melt, the ocean turning from sink to source, forest die-off and others. It seems that each individually has the potential to contribute a substantial proportion of the anthropogenic climate forcing, or of anthropogenic carbon emissions.

    Are there any studies from real climate scientists which attempt to bring together all of this into one big picture? Will there come a point where the combined effect of all these positive feedbacks is larger than the anthropogenic forcing, meaning that it’s out of our hands regardless of what we do? Have we already reached that point?

    I don’t want to be a ‘doomer’ but I think it’s important to be realistic. My understanding is that the combined anthropogenic greenhouse forcing is already about 2.6W/m², which is enough for 2°C of warming just from fast feedbacks alone, and we can’t rely on aerosols to offset that forcing forever.

    I’m concerned that we may have studies saying that there is no ‘tipping point’ for Arctic sea ice and that permafrost melt will only contribute (say) 1 billion tons of carbon per year, so that we could be complacent about each effect individually, when in reality the combined effect of all these positive feedbacks is more than enough to take the warming completely out of our hands. What do real climate scientists (as opposed to bloggers etc.) think about this ‘big picture’?

  48. 98
    Geoff Wexler says:

    Re: #81


    Sure; and not just the IPCC’s conclusions; Salby has also overthrown the conservation of mass and the acid ocean effect. Just, think of all those conclusions. That talk will go down in history

  49. 99
    Steve Metzler says:

    #91 john byatt:

    Was the Salby lecture just a hoax?

    Hmm. Now that you mention it, is there any possibility that this is a social experiment being conducted by Salby to prove that the AGW contrarians will uncritically latch onto anything that supports their anti-scientific, ideological world view?

    If he goes through with it, be interesting to see what journal he manages to get published in.

  50. 100
    Hunt Janin says:

    Re 95 above:

    Anyone have any thoughts on possible “black swan” events re Arctic sea ice?

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