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Tom Curtis at 18:49 PM on 9 July 2013No warming in 16 years
Richard Lawson @11, by my calculation you misplaced a decimal point when converting from Joules per annum to Joules per second (Watts). The correct value for the full caculation is 0.006 W/m^2 of energy used in ice melt given your initial values. That is approximatly 1% of the TOA energy imbalance.
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JasonB at 18:48 PM on 9 July 2013The Consensus Project self-rating data now available
Tom,
At least 3% of self ratings were inconsistent (ie, had at least two self ratings that disagreed). That is a much lower "error rate" than with the abstract ratings, which does not surprise given that the authors had acces to the full paper, not to mention knowledge of their intentions from which to assess their rating.
Another two points:
1. Unlike the abstract ratings, all of which had at least two raters (and therefore an opportunity for inconsistency), my understanding is that at least some (perhaps the majority?) of the self-rated papers would have been self-rated by only one author. To compare rates of inconsistency we would need to know what percentage of self-rated papers that were rated by two or more authors gave inconsistent ratings (together with assurances that the authors didn't compare notes before responding).
2. We're inferring incosistent self-ratings by fractional averages, but of course if two self-ratings disagreed by two levels (for example), the average would be a whole number and we would mis-classify that as not inconsistent.
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Richard Lawson at 18:24 PM on 9 July 2013No warming in 16 years
But it may affect the *rate* at which we increase global surface temperatures.
It is clear that energy is taken up by melting Arctic ice. I am not quite clear as to whether this is already accounted for in calculations of ocean heat content, or is it additional to OHC?
If it is additional, what proportion of the forcing has gone into melting Arctic ice? Could it be a significant co-factor in the slowed rate of increase in land surface temperatures over the last decade?
There now follows my attempt to answer this question. It comes with health warnings, as I am not a physicist, and am not even very confident with exponentials, so my conclusions may be way out.
Over 10 years 2002-2912, 10 e21 Joules have been absorbed into the Arctic ice melt.
So each year, 10e20 Joules were absorbed.
Since there are 3.15 x 10 e7 seconds in a year, that is equivalent to 3 x 10 e13 Joules per second, in other words, 3 x 10 e13 watts go to melt the ice.
The earth's surface is 5.1 e 14 square metres. Therefore the quantity of watts per square metre relating to Arctic ice melt is about 6 e-2, or 0.06 w/m2
The current level of radiative forcing due to GHGs, according to the IPCC AR4, is 1.6 watts per square meter (with a range of uncertainty from 0.6 to 2.4).
Therefore the effect of the Arctic ice melt is to reduce the effectiveness of the radiative forcing due to enhanced greenhouse gases by 3.75% (range 2.5 - 10%).
If this calculation is correct, it would seem therefore that the Arctic ice melt, if it is indeed not already accounted for in the OHC figure, is a significant component of the reduction in the rate of surface warming, and very significant al lower estimates of GHG forcing.
If all planetary ice losses (from glaciers, Greenland, and the Antarctic) were included, the contribution would be even more significant.
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Tom Curtis at 18:09 PM on 9 July 2013The Consensus Project self-rating data now available
Here are the overall stats:
Abstract ratings (columns) vs Self ratings (Rows) 1 2 3 4 5 6 7 1 8 55 87 75 1 0 0 2 3 78 171 299 0 0 0 3 3 48 141 348 2 0 0 4 3 34 144 597 0 0 0 5 0 1 4 14 4 1 0 6 0 0 3 3 0 0 0 7 1 2 1 3 2 0 0 At least 3% of self ratings were inconsistent (ie, had at least two self ratings that disagreed). That is a much lower "error rate" than with the abstract ratings, which does not surprise given that the authors had acces to the full paper, not to mention knowledge of their intentions from which to assess their rating. That some errors still existed is probably due to ambiguity or misunderstanding of what is meant by "endorse". At least one author's self ratings disagreed with the abstract ratings due to misinterpretation of the meaning of "endorse" to mean "is evidence of". Another managed to disagree with the abstract rating by redefining "the consensus" to mean that approximately 100% of warming since 1900 has been due to anthropogenic factors, something few if any climate scientists would agree with and the IPCC has never claimed. Therefore it is wrong to assume that any instance of disagreement is due to an error by the abstract raters.
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Rob Honeycutt at 17:56 PM on 9 July 2013The Consensus Project self-rating data now available
I find interesting the papers that flipped from endorsement to rejection, or vice-versa, in the process of self-rating.
Eleven went from endorsement to rejection, and 3 went from rejection to endorsement. Endorsement to rejection jumped an average of 3.4 points. Rejection to endorsement averaged 2.7 points.
But, overall, these are such a tiny fraction of the total number of papers as to be meaningless.
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Tom Curtis at 17:52 PM on 9 July 2013Climate Sensitivity Single Study Syndrome, Nic Lewis Edition
dana, the process is that they select the equilibrium climate sensitivity that, in the model gives the best match to the effective climate sensitivity, but then report the equilibrium climate sensitivity. So they are comparing effective responses, but reporting equilibrium climate sensitivity.
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BillWalker at 14:53 PM on 9 July 2013Empirical evidence that humans are causing global warming
Proofreading note: the second paragraph after "The Earth is wrapped in an invisible blanket" has a repeated sentence and sentence fragment. Please feel free to delete this comment.
Moderator Response:[GPW] Good call Sir. I decline to remove the comment, since it would also remove my thanks. Thanks too to Michael (next post).
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dana1981 at 14:14 PM on 9 July 2013Climate Sensitivity Single Study Syndrome, Nic Lewis Edition
I believe what you're describing is an effective sensitivity calculation and calling it equilibrium sensitivity, Tom.
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JasonB at 14:13 PM on 9 July 2013The Consensus Project self-rating data now available
Interesting. There were three papers that were rated as "1" by Cook et al but were self-rated as "4" by the authors, and one paper (in 2006) that was rated as "1" by Cook et al that was self-rated as "7" by the author!
I know you've attempted to maintain the confidentiality of the authors but there were only six papers rated "1" in 2006 and I think I can make an educated guess which one was self-rated as "7" just by looking at the names of the authors and without even reading the papers involved.
There were 37 papers rated as "2" that were self-rated as "4" or higher (numerically speaking), and 148 papers rated as "3" that were self-rated as "4" or higher.
If we narrow it down to papers that were rated as endorsing the consensus but were self-rated as not endorsing the consensus (i.e. not neutral), then there was only one paper rated as a "1" (mentioned above), three papers rated as a "2", and eight papers rated as a "3". Not bad.
It's interesting to see the fractional numbers that indicated authors disagreeing on the self-rating of their papers. It's instructive to realise that self-ratings aren't a gold standard that cannot be wrong, demonstrated by the fact that different authors on the same paper rated it differently.
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johnrabbit at 11:38 AM on 9 July 2013Two Expert — and Diverging — Views on Arctic’s Impact on Weather ‘Whiplash’
Is the Antarctic Jet Stream unchanged? Because of the differences between them (Southern Ocean not land mass, land at the pole etc) I would expect that the Antarctic Jet Stream should be unchanged. If it has also slowed and increased its meandering then I would reconsider the causes of the Arctic Jet Stream.
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Tom Curtis at 10:06 AM on 9 July 2013Climate Sensitivity Single Study Syndrome, Nic Lewis Edition
An ammendment to my post @42. I clearly became confused between the paper on which Lewis based his method and Aldrin et al. Nevertheless, the methods are very similar so that the method reports an equilibrium climate response is still correct.
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Tom Curtis at 09:49 AM on 9 July 2013Climate Sensitivity Single Study Syndrome, Nic Lewis Edition
dana@ 41, Lewis is correct that the paper reports equilibrium climate sensitivity. The method in the paper is to run a simple model with a tunable climate sensitivity, and from this to develop a PDF of the best prediction of transient response. The climate sensitivity needed to give that best prediction of transient response is then the result of the paper. The paper states (section 3.1):
"The equilibrium climate sensitivity is a prescribed parameter in the model that represents the feedbacks of the climate system. Although the climate system is presently not in equilibrium because of the long timescales needed for transport of heat to the deep ocean, the equilibrium climate sensitivity can still be estimated on the basis of the transient response of the model. The model is constructed so that the temperature increase will be equal to the climate sensitivity when the model is run to equilibrium with a forcing corresponding to a doubling of the CO2 concentration."
In fact, the approach used by Aldrin really represents a model based estimate of climate sensitivity, the main difference from more conventional model based estimates being that he uses the simplicity of the model to do multiple runs and thus generate a PDF. As a model based estimate, it is no more reliable than the model used. In this case the model used has surface water downwelling in polar oceans and abyssal water upwelling in the tropics, entirely contrary to the thermohaline circulation. Given that, and that the estimate is an outlier, it must be considered dubious.
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dana1981 at 08:59 AM on 9 July 2013Climate Sensitivity Single Study Syndrome, Nic Lewis Edition
"I believe that the methodology I used does actually estimate equilibrium climate sensitivity."
Then you're wrong, as is rather obvious from the fact that you're using data from a system that is well out of equilibrium. Now you can try to argue that effective and equilibrium sensitivity are identical - I've discussed reasons to very much doubt that - but you're clearly estimating effective, not equilibrium sensivity.
"Nuccitelli stated that my paper was an outlier."
It clearly is. The existence of one or two similar results (Skeie is unpublished and Aldrin does not have similar results, as discussed in the above post) does not change that - there can be multiple outliers in any data set.
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Phil at 08:42 AM on 9 July 2013Nils-Axel Mörner is Wrong About Sea Level Rise
Just some more comments on double exposures in cameras, in addition to the excellent ones made by Tom Curtis.
1. Not only is it extremely unlikely in digital cameras, it is not easy to do in film cameras manufactured since the 1970's. Most of these cameras have a mechanism that prevents the shutter being fired before the film is wound on. This mechanism needs to be overridden (if it can at all) to ensure the photographer is doing it deliberately. Cameras that allow multiple exposures are typically bulky medium or large format film cameras.
2. In order to correctly expose the film, the camera metering will need to be overridden manually by the photographer who knows they are taking multiple exposures on the same area of film. For a double exposure, each of the two exposes should receive half the light they would for a normal exposure in order for the film to receive the correct total amount of light. Or, put another way, an inadvertant double exposure would be over-exposed, bleaching out highlights and making dark areas lighter. Although it is possible to compensate for overexposure by a reduced printing/scanning time, it is typically visible in the final result (bleached out highlights cannot be magically "recovered" when they are not on the film.
It is clear that the photograph claimed to be a "double exposure" is no such thing. -
Nic Lewis at 07:31 AM on 9 July 2013Climate Sensitivity Single Study Syndrome, Nic Lewis Edition
I will (if the moderators permit) post a rather belated response to comments made by Albatross on 1 May, just to set the record straight.
I made no misrepresentation of the Aldrin et al.(2012) paper. Dealing with Albatross's numbered claims:
1) The claim that nowhere in AR4 is the mode used to quantify climate sensitivity is ludicrous. Figure 9.20 in AR4 WG1 gives climate sensitivity PDFs from a number of observationally-constrained studies. Figure 9.20 showed the median and mode (the median being marked with a dot in the uncertainty range bar, the mode being visually obvious). And the accompanying Chapter 9 text states "This figure shows that best estimates of the ECS (mode of the estimated PDFs) typically range between 1.2°C and 4°C". Far from disparaging the mode, the IPCC describe it as the best estimate.
In addition to the mode, AR4 referred to the median – the value with equal probability (area under the PDF) above and below it. However, it would have been difficult to be certain of the accuracy of a median estimate measured from Figure 6.a) of Aldrin et al 2012, and the mode has the advantage of being less affected than the median by the choice of prior distribution. I do not consider the mean, quoted by Aldrin et al., to be a suitable central measure for climate sensitivity PDFs, because the PDFs are skewed. Consistent with my view, the relevant chapter of IPCC AR4 refers to modes and medians for climate sensitivity estimates, but not to means. The IPCC also gives uncertainty ranges for climate sensitivity estimates. Likewise, I gave in my paper the 5–95% climate sensitivity range for the main Aldrin et al. (2012) results, of 1.2–3.5°C.
2) Albatross repeats the unfounded claim by Dana Nuccitelli that the main results climate sensitivity estimate I cite from Aldrin's study excludes cloud and indirect aerosol effects. It seems that neither of them have read Aldrin et al (2012); certainly they lack even a basic understanding on this point. Sections 2.3 and 4.8 of the paper show that the study did include indirect aerosol forcing (cloud albedo effect), and Table 1 and Figure 4 of the Supplementary material give details of the prior distribution used for the main results.
3) In support of his misrepresentation allegation, Albatross goes on to draw on Nuccitelli's claim that "When Aldrin et al. include a term for the influences of indirect aerosols and clouds, which they consider to be a more appropriate comparison to estimates such as the IPCC's model-based estimate of ~3°C, they report a sensitivity that increases up to 3.3°C". As stated under 2) above, the Aldrin et al. (2012) study does make allowance for a negative cloud albedo indirect aerosol effect. Its main results do not make explicit allowance for any cloud lifetime indirect aerosol effects.
However, if Albatross or Nuccitelli understood Bayesian statistical inference and the relevant climate science, and had studied Aldrin et al.'s paper closely, they would realise that, as it is a hemispherically-resolving observationally-based study, all indirect aerosol effects, including any negative cloud lifetime effect, would already be fully reflected in the (posterior PDF) estimate of the cloud albedo indirect aerosol effect. Only if the prior distribution for the aerosol indirect effect did not extend to sufficiently negative values would that not be so. But the 2nd panel of Figure 15 in Aldrin et al.'s Supplementary Material shows that, far from that being the case, the 95% uncertainty range for the aerosol indirect effect prior distribution extends well beyond the 95% range for the posterior PDF on the negative side, but not on the positive side. Therefore, the observational evidence for any actual negative cloud lifetime effect will be fully reflected in the main results.
However, when the aerosol indirect effect prior distribution is made more negative still to allow for a possible negative cloud lifetime effect, it overlaps even less with the values implied by the observations. Therefore, the resulting increase in estimated climate sensitivity merely reflects the new prior assumption, that the cloud lifetime effect is material, overriding the best observational evidence. Moreover, recent mainstream estimates of the uncertainty range for total indirect aerosol forcing are much less negative than that assumed by Aldrin et al. Accordingly, Aldrin et al.'s main results sensitivity estimate is the appropriate one to compare with the IPCC's estimates, not the alternative estimates with even more negative aerosol forcing prior distributions.
Incidentally, Karsten's comments about aerosol forcing estimates in my study are also completely wrong, and show a fundamental lack of understanding of the estimation methods used.
I also take this opportunity to comment on some other unfounded claims made by Dana Nuccitelli in the main 'Nic Lewis single study syndrome' article
a) Nuccitelli claims: "The methodology used by Lewis is also not even necessarily an estimate of equilibrium sensitivity, but rather of effectiveclimate sensitivity, which is a somewhat different parameter."
I believe that the methodology I used does actually estimate equilibrium climate sensitivity. I suggest that Nuccitelli reads the relevant papers by Chris Forest and his co-authors if he wants to understand why that is. In any event, I would point out that the x-axis of Fig 9.20 in the IPCC AR4 WG1 report, where the F06 and other sensitivity PDFs were shown, is labelled "Equilibrium Climate Sensitivity" and in the text the estimates are described as being of equilibrium climate sensitivity (using the acronym ECS), notwithstanding that several of the studies (such as Gregory 02 and Forster/Gregory 06) actually estimated Effective Climate Sensitivity, indicating that the IPCC, correctly in my view, in practice sees very little difference between the two.
certainly are for estimates of effective climate sensitivity. That indicates that the IPCC authors, correctly in my view, see little practical difference between estimates of effective climate sensitivity and estimates of equilibrium climate sensitivity.
b) Nuccitelli floated "The Climate Variability Question Mark in Lewis' Approach". Referring to the 2013 study by Olson et al., he stated that they investigate "three main sources of what they call "unresolved climate noise": (i) climate model error; (ii) unresolved internal climate variability; and (iii) observational error".
In fact, Olson et al. focus only on item (ii). Their findings have limited relevance to my study, which (a) makes due allowance for internal climate variability and the uncertainty arising therefrom; (b) does not attempt (as Olson et al. did) to estimate aerosol forcing from purely global temperature measurements; and (c) avoids the uniform priors they use.
c) Nuccitelli stated that my paper was an outlier. If it were, as his title suggested, the only study showing a low climate sensitivity – one below the bottom of the IPCC 4th assessment report (AR4) 2–4.5°C 'likely' (2/3rds probability) range – then that would be a fair point. But it seems increasingly clear that warming over the instrumental period (from the mid/late nineteenth century to date) indicates a lower 'likely' range for climate sensitivity than 2–4.5°C.
As well as the Norwegian study (Skeie et al.) to which Nuccitelli referred, four recent peer-reviewed instrumental-observation-constrained studies (Ring et al, 2012, Atmospheric and Climate Sciences; Aldrin et al., 2012, Environmetrics; Otto et al., 2013, Nature Geoscience; and Masters, 2013, Climate Dynamics) all point to a considerably lower 'likely' range for climate sensitivity than 2–4.5°C.
d) Nuccitelli stated that the Bayesian approach I employed involves "making use of prior knowledge of climate changes to establish a probability distribution function for climate sensitivity".
In fact, the purpose of my using an objective Bayesian approach was to avoid making use of prior knowledge or assumptions about the likely values of the climate system parameters being estimated. Typically, Bayesian climate sensitivity studies have inappropriately used a wide uniform prior distribution for climate sensitivity (and often for other key parameters), and thereby greatly exaggerated the risk of climate sensitivity being high.
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michael sweet at 06:49 AM on 9 July 2013Nils-Axel Mörner is Wrong About Sea Level Rise
Klaus,
There are a host of questions that Nils-Mormer needs to address. He has provided no evidence that this tree was located in an isolated position 50 years ago. As Tom pointed out above, this type of tree is common in locations of retreating coastlines. No picture or evidence of any tree from the 1950's has been produced, only an unlikely hearsay story. Nils-Morner has produced several photos of different trees, that he claims are the same tree, most of which show only sea in the background so that they are not identifiable. If the photos were taken with identifiable background the questions would be easily resolved. All the photos show evidence of erosion consistent with rising sea levels. No photos have been produced of a tree pushed over. The most likely explaination of any similar tree falling is erosion caused by rising sea levels. No information has been produced to support Nils-Morner's outrageous claim that scientists pushed the tree over, only an unsupported claim of a hearsay story. How many contradictions do you need to have pointed out before the story is thrown out as false? My limit was passed long ago.
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pvincell at 06:28 AM on 9 July 2013BC’s revenue-neutral carbon tax experiment, four years on: It’s working
Three self-described conservatives on climate change and its solutions. http://bit.ly/135gvNa.
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jdixon1980 at 05:56 AM on 9 July 2013Climate Change Denial now available as Kindle ebook
c.change @ 1: Reading the vast range of material on this website comes with a subscription price of $0 (and as I understand it, there are no big sponsors, making most of the work that goes into the website volunteer work), so I was quite happy to pay Cook and Washington for their book. I don't think diminishing their financial resources still further by giving away their book for free will help their website, which is making a big splash.
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dana1981 at 01:46 AM on 9 July 2013The Consensus Project Update and Dana on Al Jazeera Inside Story
Yes I was very impressed by Shihab Rattansi during both shows. He does his research and knows his stuff and does a very good job facilitating the discussion.
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Eric (skeptic) at 01:39 AM on 9 July 2013Two Expert — and Diverging — Views on Arctic’s Impact on Weather ‘Whiplash’
I have a somewhat contrary view than previous commenters about this subject. As near as I can tell the scientific consensus through the early 2000's was for a stronger jet (less meridional variation). An example paper is http://www.esrl.noaa.gov/psd/people/dezheng.sun/lectures/nao/thompsonetal2000.pdf I have seen no comprehensive study that contrasts any new theory to this old one.
The AO as mentioned in the paper is not a one-for-one proxy for the sub-polar jet. But generally the more positive the AO index, the stronger the jet. The trend was positive to around the early 1990's; see this thread for the graph: http://www.skepticalscience.com/jetstream-guide.html The main reason is that the cooling stratosphere, including the Arctic, and the warming troposphere which includes AA, should increase both the vertical and horizontal temperature gradients at the tropopause at the boundary of the Arctic. This would induce a stronger jet, on average.
The recent weakening of the jet, or more negative AO, is likely IMO to be natural.
I agree with Agnostic that various effects should be seasonal. While the recent drop in AO in winter may be natural IMO (following a cycle of rising from the 70's through the earily 90's), there ought to be an anthropogenic rise in summer basically due to higher pressure at the north pole. An annual plot would obscure this trend. It is also contrary to the argument I made above about the gradient. It is also noted by Chris G above, that the jet is driven by the patterns of high and low pressure rather than vice versa.
A related consideration is the strength of the Aleutian and Icelandic lows which would likely deepen in all seasons helping sustain a stronger jet and positive AO. But they could also be unbalanced (they take turns being strong and weak).
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Klaus Flemløse at 01:31 AM on 9 July 2013Nils-Axel Mörner is Wrong About Sea Level Rise
I am confused about the sequence of events around the tree and the photo/film taken.
It seems that Mörner and his team arrived at the scene after the alleged climate scientists have overturned tree.
The explanation for the movement of the tree relative to the oval stone is presumably, that it has been raised elsewhere than where it originally stood. How many meters has it been move away from the original position?
In respect of picture replacing the photo shop picture, there is a question about when it was taken. Before or after Mörner and team raised the tree again?
Why did't Mörner informed the public that the film and photo was a reconstrution and not reality ?
I am still confused and I hope Prof. Nils-Axel Mörner is able to make public the documentation needed so no doubt exists.
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jdixon1980 at 00:57 AM on 9 July 20134 Hiroshima bombs worth of heat per second
The whining sound effect of the hair dryers could be amplified the more people are in view - e.g., you might show the teacher shouting or talking in a bull-horn to teach the day's lesson over the din of several hundred hair dryers...
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jdixon1980 at 00:54 AM on 9 July 20134 Hiroshima bombs worth of heat per second
theelf @ 1: "The anology of each of the 7.1 billion people on the planet continuously running about two dozen 1500-watt hair dryers might also be a useful, although it is hard to imagine 7.1 billion."
Isn't the point, though, that you don't have to imagine 7.1 billion to understand this analogy? The 7.1 billion is just a scaling factor that could just as easily be left out; all you have to do is imagine everyone, everywhere running two dozen hair dryers constantly, which could be a very funny image. I picture the following cartoon: a goofy looking human in a bath towel running a dozen hair dryers in each hand, and then zooming out to bring all of their neighbors into view doing exactly the same thing, then panning over to show a busy city sidewalk packed with people rushing to work with a briefcase and a dozen running hair dryers in each hand (either with arms at their sides, or perhaps even up above their heads continuing to dry their hair as they walk, briefcases dangling in the air), and then zooming out again to show the same scene carried out on every city sidewalk. Then, maybe a time lapse, and show people doing it on the job - at their desks in front of computers, on construction sites, standing up at a chalkboard in front of a classroom (each student also holding the two dozen hairdryers at their desks).
Admittedly, the message is no longer bite-sized once you've gone to this extent of production, and the cartoon might only be viewed by people who already understand that we have a real problem on our hands.
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citizenschallenge at 23:11 PM on 8 July 2013Climate Change Denial now available as Kindle ebook
Excellent book, I've already got the hard copy, but I do keep wondering...
When is the audio version coming out ?
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sylas at 22:45 PM on 8 July 2013Agnotology, Climastrology, and Replicability Examined in a New Study
Skeptical Science has a particular interest in communication techniques... this paper seems to represent an instance of a new experiment in communication across the divide with writers who deny conventional aspects of climate science.
The reviews and responses are also an interesting study. in communication problems. The nature of the subject matter is going to make it hard to get a reviewer who has relevant expertise but does not have a personal stake in the subject.
It's amusing to see insulting content clothed in terms of politie discourse. The classic is where Hanekamp adds an extra comment just to say: "I would like to thank Ben-estad et al. for the exchange with me. It has given me a wealth of information for my philosophy classes."
The appropriate response would be, I suggest, be along the lines of: "We are delighted that these exchanges will be of use to your philosophy students. Indeed, we'd be willing to come and give a guest lecture on the matter, which would doubtless be of considerable benefit to your students."
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c.change at 21:53 PM on 8 July 2013Climate Change Denial now available as Kindle ebook
Thanks John and Haydn for what must have been a massive amount of time and effort into publishing this much needed book.
In order for this book to get the readership it deserves please consider making the purchase price $0 (free!)
If this book was in the public domain it could become the definitive text book in the psyological war against not only climate deniers but also motivation for climate change believers who are currently sitting on the fence.
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Cornelius Breadbasket at 18:14 PM on 8 July 2013The Consensus Project Update and Dana on Al Jazeera Inside Story
It is Shihab Rattansi who does Inside Story for Al Jazeera. He is brilliant - knows his stuff and how to communicate.
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Riduna at 16:01 PM on 8 July 2013Two Expert — and Diverging — Views on Arctic’s Impact on Weather ‘Whiplash’
Dr Francis talks about the effects of diminishing heat gradient between the Arctic and Northern tropics resulting in weakening of the jet stream with consequential transfer of heat northwards and cold southwards. It seems to me that her argument that this diminishing gradient is brought about by transfer of water vapour into the Arctic producing temperature amplification and loss of sea ice is both plausible and likely - at least in summer.
However, I find it difficult to believe that this could occur during the winter months when sunlight hours are low, as are Arctic temperatures. So, should we not expect jet stream weakening to occur only in the warmest Arctic months? Is there evidence that it occurs outside these months?
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One Planet Only Forever at 15:00 PM on 8 July 20132013 SkS Weekly News Roundup #27B
Trapping CO2 underground, as presnted by Denise Chow on LiveScience, is not a sustainable activity. Technically it may seem like a solution but it really isn't helpful.
In fact, burning fossil fuels is not sustainable because eventually future generations will not be able to continue the practice. So the burning of fossil fuels needs to be reduced.
In addition to the fact that burning fossil fuels is not sustainable, there are many other impacts from the extraction, transport, processing and ultimate burning of fossil fuels, even sweet natural gas, that accummulate (are not sustainable).
A current generation may be able to get a short-term benefit from activities that are not sustainable, but those activities create negative consequences for future generations. The global economy cannot be expected to sustanably grow as long as so much of its activity is simply not sustaianble. It is as simple as that.
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JohnMashey at 14:51 PM on 8 July 2013Agnotology, Climastrology, and Replicability Examined in a New Study
Can you say anything on the prcoess from here and guess at schedule?
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Tom Curtis at 10:09 AM on 8 July 2013Nils-Axel Mörner is Wrong About Sea Level Rise
Klaus Flemlose @69, thank you for that find. That is indeed the tree with the mark, and Axel-Morner's appearance therefore positively identifies the tree as being the one he is talking about. As the picture I reffered to above was very grainy, I have made a screen capture and reproduced the picture below:
Further, comparison of this picture with the "before" picture shown @55 shows they are pictures of the same tree, probably taken at the same time. The "before" picture, therefore, does not show that the sea was much closer than in the "after" picture, but merely shows a grainier picture with a higher tide.
(I should note that picture you showed @56 may also be using natural variation to conceal the sea level rise. In that case, I would suggest, the erosion shown is likely to have been from a recent storm surge.)
What is most interesting about the video, however, is the way that Axel-Morner so casually leans against the tree:
He does this while telling us that the tree has not been knocked down in fifty years.
Later, refering to the time of that filming he had this to say:
"This tree, which I showed in the documentary, is interesting. This is a prison island, and when people left the island, from the ‘50s, it was a marker for them, when they saw this tree alone out there, they said, “Ah, freedom!” ... I knew that this tree was in that terrible position already in the 1950s. So the slightest rise, and it would have been gone. I used it in my writings and for television.
You know what happened? There came an Australian sealevel team, which was for the IPCC and against me. Then the students pulled down the tree by hand! They destroyed the evidence. What kind of people are those? And we came to launch this film “Doomsday Called Off,” right after that, and the tree was still green. And I heard from the locals that they had seen the people who had pulled it down. So I put it up again, by hand, and made my TV program....
They call themselves scientists, and they’re destroying evidence! A scientist should always be open for reinterpretation, but you can never destroy evidence. And they were being watched, thinking they were clever."
So, according to his later account, the tree had just been propped up by hand. Yet in the film, he casually leans against it and it is rock steady.
Well, we already knew the story of the vandalistic Australian scientists was a fiction, but it is nice to have additional confirming evidence. It is also interesting to see the nature of Axel-Morner's scientific ethics. "[You] can never destroy evidence", he writes, but he is certainly not averse to manufacturing it.
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Tom Curtis at 09:37 AM on 8 July 2013CO2 effect is saturated
basnappl @234, first a correction. I thought the copy of Griggs and Harries 2004 was a preprint of the paper you were looking at. In fact, you were looking at Griggs and Harries 2007, which is a seperate (although related) paper. Based on that, my comment @233 is correct so far as it goes. That is, observations of changes in OLR match those predicted by models, within observational limits of ghg, temperature and H2O profiles. That is, the slight discrepancy you have pointed out results from our limited knowledge conditions within the atmosphere rather than any failing of Line By Line (LBL) or Band models of radiative transfer.
One thing we do know is that those radiative transfer models are extraordinarilly accurate. This is shown by the match between one particular model and observations shown in the graph below:
(For more examples, see my discussion here and my article here.)
Because of these tests of accuracy when the conditions are well known, and because radiative transfer models are based on very well known physics, the discrepancy you point to is almost certainly the result of atmospheric conditions rather than deficiencies in the radiative transfer models. That being the case, there is no question of the greenhouse effect being saturated, for all radiative transfer models predict the logarithmic relationship between CO2 concentration and radiative forcing, ie, that you get approximately the same increase in forcing for each doubling of CO2.
It is interesting, however, to look at the reason for the "zero signature" between 1997 and 2003. Griggs and Harries are more explicit in 2007 than in 2004, attributing the lack of signature to temperature profile. As it happens, using the lapse rate it is possible to use the brightness temperature as a rough indicator of altitude. If we do so, we see that in order to have zero influence in the band in question, the increase in CO2 between 1997 and 2003 would need to be matched by an increase in temperature at 7-10 km altitude greater than that at the surface, and that expected by the models. In other words, it appears that Griggs and Harries have found a tropospheric hotspot.
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Andy Skuce at 08:47 AM on 8 July 2013The Consensus Project Update and Dana on Al Jazeera Inside Story
tcflood: I agree that SkS could do with more coverage of solutions and that our team would be strengthened if we had more contributors with expertise in energy and economics solutions. We are always open to contributions from new authors. (Hint)
Dana, rustneversleeps and I have all written recent articles on carbon taxes and carbon capture and storage and we intend to do more in the future.
One problem is that, when it comes to alternative energy and climate economics, there is a relative scarcity of peer-reviewed material to draw upon compared to the physical sciences. And, certainly, when it comes to controversial matters such as peak oil, nuclear energy, geoengineering and so on, there is nothing approaching a 97% consensus. (As far as I can tell, there is no issue in the entire field of economics on which the majority of experts can agree.)
So, any "solutions" articles we write will necessarily be more subjective and less reliably referenced--and more contentious--than the hard science material that is the main focus of SkS.
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tcflood at 06:52 AM on 8 July 2013The Consensus Project Update and Dana on Al Jazeera Inside Story
I was amazed by the quality of the interview conducted by the AJ interviewer – I didn’t get his name. He was so much more widely and deeply informed than any American media interviewer I’ve heard. If only msnbc did this kind of work instead of burying its lens up Ms. Palin’s you-know-what.
He asked some excellent questions regarding policy and economics that didn’t play so much to the central forte of his guests. I also noticed that the issue of whether nuclear energy will need to be a part of the complete solution to generate a fossil-fuel-free energy sector was never mentioned.
I wonder if SkS would benefit from some resident policy and economics wonks. Some articles/threads by someone really knowledgeable about electricity transmission and grid technology and management would be hugely valuable. Threads discussing grid integration of intermittent sources and its cost and the extent and costs of required backup, etc. would be very valuable.
You guys are extremely good at the science of AGW and at making the argument for stopping bulk CO2 emissions, but that’s only half of the discussion. I think your site would become even more influential if you developed as expert a discussion of the other half of the problem – solutions.
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rockytom at 04:30 AM on 8 July 2013The Consensus Project Update and Dana on Al Jazeera Inside Story
Dana, it was good to see you "in person." All the guests in the two shows in the post were knowlegeable and contributed wisely to the discussion.
My main concerns continue to be the irreversable limits we have already passed. Some are more obvious than others. The ice sheets and glaciers are melting and sea level is rising. Extreme weather events are increasing both in number and intensity. Ocean waters are becoming more acidic. We know that there is enough carbon already in the climate system "pipeline" to allow these processes to continue for some time. We should also be discussing these consequences and how much time the next generations will have to deal with them as we inevitably reduce carbon pollution. We don't have all the answers (i.e., all the potential consequences) but we have enough to begin discussions.
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Bob Loblaw at 01:17 AM on 8 July 2013Two Expert — and Diverging — Views on Arctic’s Impact on Weather ‘Whiplash’
william:
Further to chriskoz's comment about the naming of the cells (just the tropical one is the Hadley cell), the boundary between the Polar and Ferrell cells is a bit more complicated than the old three-cell visual.
Winds blow because of a difference in air pressure. We are used to looking at air pressure at the surface, but atmospheric circulation also depends on pressure at different heights in the atmosphere - and differences in pressure. The idea of the Polar/Ferrell/Hadley cell circulation fits the early knowledge of surface pressure and wind patterns, but the high-altitude winds are a bit different.
Even with the same surface pressure in two regions, different air temperatures would mean different pressures at altitude. Cold air is more dense than warm, so starting with the same surface pressure and moving upwards, the colder location will see pressure dropping more rapidly. (Pressure is just the weight of the overlying air.) Consequently, at high altitude there will be a lower pressure in the cold location than in the warm, so you have a high-altitude pressure difference, and thus can have high altitude winds even though the surface pressures are equal. The pressure relationship to temperature differences is call baroclinicity. Wikipedia has an entry on thermal winds, and one on baroclinicity.
There is a strong temperature contrast between the Polar and Ferrel cells. The resulting thermal conditions lead to the jet stream - high altitude baroclinic winds. Just as surface winds can be seen to follow the patterns of surface pressures, the jet stream can be seen to follow the patterns of the high-altitude pressures.
Just to confuse things, meteorologists do not draw maps of the pressure at a constant altitude for upper air analysis. Instead, they pick a constant pressure, and determine what altitude you find that pressure at. The map will have the same pattern of highs and lows, but it's a slightly diffeerent way of thinking of things. Here is the web page of Environment Canada showing some of the maps available for analysis, and here is the map for the 500mb (500 hPa in SI units).
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sylas at 01:09 AM on 8 July 2013No warming in 16 years
Richard... yes, sort of... though it doesn't mean much. The Earth is heating up, and most of the absorbed energy goes into heating the ocean. According to the figures; 93.4% of it. Of the rest, 2.1% is taken up as heating of continents, and 0.8% is taken up as melting Arctic sea ice. So you can divy up those numbers in various ways. I don't recommend it; it muddles much more than it reveals.
If the sea ice wasn't there to be melted, then everything changes; because it's a complex interacting system we are considering. For example, the loss of sea ice in summer is a significant feedback that contributes to the magnitude of all changes. You could consider a conterfactual in which melting ice isn't particularly endothermic, so that no energy was taken up, any excess energy would be taken up mostly in the ocean; meaning very little difference in land temperatures. We already know that when there's excess energy around, it goes mostly into the ocean.
The other issue is that temperature is not heat.
The temperature we get to is not determined by heat capcities; but simply by what temperatures will bring radiation emitted into balance with radiation absorbed. Heat capacities -- and the absorbing of excess energy -- is part of the process of getting back into balance.. and this is about how long it will take for temperature to stablize for a given atmosphere or forcing.
The energy figures are not really about temperature, but about the imbalance and the time it will take to get to balance again.... whatever temperature that happens to be. Getting rid of the capacity of melting ice to absorb heat would mean only we get to equilibrium temperature a tiny little bit faster. It makes no difference to the temperature we actually reach.
Moderator Response:[JH] I deleted your duplicate post of the above.
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Richard Lawson at 00:21 AM on 8 July 2013No warming in 16 years
Thanks Sylas. So is it possible and/or justifiable to calculate the surface heating that would have taken place had that 10^21 J gone into warming the atmosphere instead of into melting Arctic ice?
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sylas at 23:32 PM on 7 July 2013No warming in 16 years
Richard, your estimate looks good.
Skeptical Science have used 0.5 W/m^2 as the energy imbalance for Earth... this is the energy going into heating the planet. At 5.1e14 m^2 for Earth's surface, and 3.15e7 sec per year. and for a 16 year period of time, you have about 1.3e23 J of energy heating the Earth. Using 0.8% of this into Arctic Sea ice (from the diagram above) this corresponds to 10^21 J. Same as you have calculated.
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R. Gates at 22:35 PM on 7 July 2013Two Expert — and Diverging — Views on Arctic’s Impact on Weather ‘Whiplash’
This was a very interesting post and certainly displays that even two experts on the "consensus" side can disagree about the details of the disruptions caused by anthropogenic climate change. The contrast in perspectives between Dr. Trenberth and Dr. Francis is actually quite refreshing. I tend to personally favor Dr. Francis in this particular difference of opinion.
From a larger perspective, the high amplitude jet stream patterns we are see are yet one more global example of a positive feedback mechanism whereby the overall increase in energy in the Earth system is trying to balance between pole and equator. The meridonal advection of energy brought about by this pattern is enhanced such that we get more vigorous equator to pole mixing. We are seeing the exact same thing higher in the stratosphere and even the mesosphere with an enhanced Brewer-Dobson circulation.
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sylas at 22:27 PM on 7 July 2013No warming in 16 years
Richard, your estimate looks good.
Skeptical Science have used 0.5 W/m^2 as the energy imbalance for Earth... this is the energy going into heating the planet. At 5.1e14 m^2 for Earth's surface, and 3.15e7 sec per year. and for a 16 year period of time, you have about 1.3e23 J of energy heating the Earth. Using 0.8% of this into Arctic Sea ice (from the diagram above) this corresponds to 10^21 J. Same as you have calculated.
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francis at 21:57 PM on 7 July 2013Two Expert — and Diverging — Views on Arctic’s Impact on Weather ‘Whiplash’
The mechanism linking Arctic amplification (AA: increased sensitivity of the Arctic to global warming or cooling) to changes in the jet stream that Steve Vavrus and I proposed and demonstrated in our March 2012 paper involves more than just sea-ice loss. While the ice loss is the largest contributor to AA in fall and early winter, rapid Arctic warming is also driven by the pronounced negative trend in snow cover on high-latitude land in spring and early summer, and even more strongly by the increase in water vapor at high latitudes, which affects AA in all months. That water vapor warms the Arctic in all seasons in 3 ways: it is a greenhouse gas, it releases latent heat into the atmosphere when it condenses into clouds, and those additional clouds also trap heat below them. Most of the modeling studies to date that examine the Arctic’s effects on the large-scale atmospheric circulation have focused only on the influence of sea-ice loss. I believe this is the reason that most of those studies fail to find a robust response, while the real world (which DOES include all the contributions to AA) is responding more strongly.
As commentor #8 points out, most of the modeling studies also average over time and over many ensemble members, which would smear a signal of a more amplified jet stream if those meanders did not occur in the same location. Take March 2012 versus March 2013, for example. In both cases the jet stream was highly amplified, but in 2012 there was a trough over the western U.S. and a large ridge over the east, which led to the breaking of thousands of high temperature records. A year later, the trough-ridge location was opposite but equally anomalous. Averaging over the two years would produce no signal.
It is also important to note that AA has emerged from the noise of natural variability only in the last decade or two (challenging tests of statistical significance), it is strongest in the fall and near the surface (because of sea-ice loss), and it is now becoming evident in all seasons and through a deep atmospheric layer (because of increased water vapor). This must inevitably have a more pronounced effect on the polar jet stream as we continue to warm the planet by burning fossil fuels.
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Klaus Flemløse at 20:52 PM on 7 July 2013Nils-Axel Mörner is Wrong About Sea Level Rise
I think, I have found the stockmark picture mentioned in post 55. It can by found in the video: http://www.youtube.com/watch?v=gZS2eIRkcR0 after 7 minutes and 42 second. The logo originates fra Newsworld. There is a cut in the video so it is not possible to make sure it is the same tree.
8.june 2013, 11.00
Before the cut we can se the ocean with a clear horison without any ships. After the cut , there are many ships in the horison. This means it is two different sequence taken at different times and different angels. Prof. Mömer is standing close to the tree and we can't se the whole tree. Does this mean, that it is a case of another photo manipulation ?
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chriskoz at 19:06 PM on 7 July 2013Two Expert — and Diverging — Views on Arctic’s Impact on Weather ‘Whiplash’
william@7,
You understand the things correctly (but your "Polar Hadley cell" is just called "Polar cell"), it's worth quoting this excellent article by John Mason here based laregely on Francis 2012.
However that's not the primary point of contention between Kevin & Jennifer above. The point is, that Kevin looks to me like climate scientist who averages everything (i.e. colder conditions in Arctic mean slower heat transfer therefore no large T swings expected) denying the variability of weather where he does not seem to specialise. To which Jennifer (both climate & weather specialist) replies that heat transfer is not by convection but by fast blowing wind which is simple and modest and dead-on accurate in rebuting his claim.
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Richard Lawson at 18:38 PM on 7 July 2013No warming in 16 years
Another factor, or maybe a subset of the ocean heat uptake, is the meting of the Arctic Ice. It is noteworthy that the ice melt has speeddecades once 2001. I have calculated that some 10^21 Joules have gone into melting the ice since 1997. http://greenerblog.blogspot.co.uk/2013/07/how-much-heat-has-gone-into-melting.html
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chriskoz at 18:08 PM on 7 July 2013The Consensus Project Update and Dana on Al Jazeera Inside Story
If you think Arabic language + google translate = imperfect text, check for example this translation of AJ commenting on recent tornadoes in OK. I'm just shocked with surprise: apart from few obvious misnomers: lack of distinction tornado vs. hurricane (maybe due to Arabic language nuances that someone speaking that language can explain), the translation reads perfectly clear and accurate, far clearer than most Fox, CNN, WSJ nonsense, where language is not a barrier for English reader.
In particualer, everything what Mike Mann has said is quoted without misrepresentation after this double translation. Why? Because the sound and honest journalism by the author (Yasser Aerami) + impartial google translator can confuse some technical words but cannot distort the meaning. On the other side, a human translator can be very biased and can distort the meaning (as we've seen meny times from denialists) and produce the text so obfuscated as sometimes incomprehensible. The climate science became comprehensible to me only after I started to read SkS. In terms of Climate News, AJ stands among those Fox, CNN, WSJ obfuscators like SkS stands among WUWT and the like.
Dana, I cannot wait AJ launch in Amerika. Hopefuly they be able to stream something over internet because Im located in AUS. Let us know.
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sylas at 17:59 PM on 7 July 2013Agnotology, Climastrology, and Replicability Examined in a New Study
In the interactive comments for review of this paper, in a reply by Rasmus ("SC C292: 'Reply to Ellestad/Solheim/"klimarealistene"', Rasmus Benestad, 25 Jun 2013"), there is a reference to a scanned copy of a letter:
I will maintain that Ellestad and “klimarealistene” are engaged in a propaganda campain. On February 3rd 2012, Ellestad wrote a letter to the director at MET Norway in an attempt to gag me, after I had commented on the Humlum et al (2011) paper on the website of a Norwegian newspaper. (A scanned copy is available on-line: https://drive.google.com/?usp=chrome_app#folders/0B5ZHm1tjzEtDWjhWZmxIQzVVSWc)
The link provided does not work. Is the scanned copy still available anywhere? Thanks!
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basnappl at 15:00 PM on 7 July 2013CO2 effect is saturated
Hello Tom,
Thanks for the reply. I read through the preprint as best I could. I am unfamiliar with the models used and some of the terminology. Is it true that, in their analysis, the temperature profile of the atmosphere is the fitting parameter?
As far as how well I represented their claims, I will quote with some (perhaps unnecessary) context:
First quote, commenting on the difference spectra figure I included in my previous post:
"An initial inspection indicates that the processing of the data has not caused any major artifacts. In all cases the difference spectra are seen to have consistent and reproducible
features. The only sign of asymmetry (which could indicate a mismatch of wavenumber scales between the spectra) is in the CO2 (0110 → 1000) band at 720 cm-1, which may be due to its position on the very steep high frequency wing of the CO2 fundamental centered
at 667 cm-1."Second quote, in reference to the same:
"A negative brightness temperature difference is observed in the CO2 band at 720 cm-1 in the IMG–IRIS (1997–70) and the AIRS–IRIS (2003–1970) difference spectra, indicating increasing CO2 concentrations, consistent with the Mauna Loa record (Keeling et al. 1995). However, this channel in the difference is also sensitive to temperature, and we note that in the 2003–1997 difference, despite a growth in CO2 between these years, there is no signal at 720 cm-1."
Third quote is where the portion in my previous post comes from, now with context:
"The CO2 band at 720 cm-1, though asymmetric for the reasons stated earlier, nevertheless shows some interesting behavior, with strong negative brightness temperature difference features for 1997–1970 and 2003–1970: whereas, the 2003–1997 (a much shorter period, of course) shows a zero signature. Since we know independently that the CO2 concentration globally continued to rise between 1997 and 2003, we must conclude that the 2003–1997 result must be due to changes in temperature that compensate for the increase in CO2. This would mean a warming of the atmosphere at those heights that are the source of the emission in the center of this band. This is somewhat contrary to the general (small) cooling of the stratosphere at tropical latitudes." (emphasis mine, I'm only trying to show where my "explanation" came from)
Fourth quote, regarding differences between model results and observations:
"Finally, there exists a marked gradient in the simulated spectrum between 800 and 700 cm-1, which is absent in the observations. This coincides with the far wings of the strong CO2 band centered at 667 cm-1. In sensitivity tests, this gradient showed sensitivity to the amount of CO2, and is therefore related to the strong CO2 band, and may reflect reanalysis uncertainties in temperature."
The paper includes appendices detailing the temperature profiles used to coerce the models to the data.
I would appreciate some help digesting this.
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Tom Curtis at 11:23 AM on 7 July 2013CO2 effect is saturated
basnapple @232, I have difficulty reconciling your description of the "explanation" by Griggs and Harries with that which they offer in the preprint version of their paper.
Specifically, in that version they show (Fig 3 a&b) that two popular reanalysis products do not predict the observed changes in OLR. They also show, however, that there is a profile constrained by observations that does predict the observed changes in OLR (Fig 3 c). That means the observed changes in OLR are consistent with the expectations of radiative physics plus observed changes in gas and temperature profiles, even though the observations of those profiles is of insufficient resolution to permit accurate prediction of these small changes in OLR. As they put it,
"Simulations created using profiles merged from a number of datasets show that we can explain the differences seen in the CO2 and ozone bands by the known changes in the those gases over the last 34 years."
This contrasts sharply with your claimed "explanation", which is of course no explanation at all. Converting a claim that changes in OLR lie within those expected given known limits of observation, and hence that there is no discrepancy, to a claim that a discrepancy exists for which there is no explanation is very substantial. I doubt that editorial review would have forced so large a change on the paper. Nevertheless I ask that you quote the original sections of the paper as published to show that you have indeed fairly represented Griggs and Harries.
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basnappl at 10:05 AM on 7 July 2013CO2 effect is saturated
Sorry for my various typos. I should have read it over before submitting!
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