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Comments 74851 to 74900:

  1. Chasing Pielke's Goodyear Blimp
    The titles are just fine. They are not ad hominems, describing a bad argument as a bad argument is not 'argumentum ad hominem' it is an observation on the value of the argument itself not an attribute of the arguer. 'Crocks' and 'slip-ups' are just colloquial synonyms for bad argument.
  2. Chasing Pielke's Goodyear Blimp
    Sorry, bad joke Seriously, there is the alternative of just labeling the buttons 'Roy Spencer', etc. That also widens the expectations of the content therein.
  3. One-Sided 'Skepticism'
    174 - Eric (skeptic) "first, this thread is not an "invitation" by any stretch of the imagination." It has several links to his blog and comments on the blog entries... I really don't think it takes any stretching of the imagination to see that that is an invitation. "Now the Christy crocks issues are in two places. But for dana1981's decision to pick on Christy above, Spencer slip ups would be in two places as well." Great - two places in which to reply. Those are not, by far, the only places where there is more than one appropriate thread to discuss a single issue. If that's a problem, the "Comments" button is your friend. "Unless I am mistaken, the discussion of Pielke's topic, the satellite data, is nowhere." And, indeed, Pielke has not case for complaining about the treatment of himself by SkS - he's proxy complaining. "Specifically how is the integrity of SkS being defended?" Because, as I said before, people often complain that they get censored or abused if the post contrary opinion on SkS. As you know more than most - and now Pielke knows; and anyone who cares to actually read the comments knows - people get to post all kinds of stuff and get plenty of discussion - with in the terms of the comments policy. That is clearly a demonstration of a site with integrity. Hope that helps.
  4. Chasing Pielke's Goodyear Blimp
    'Crocks' are well known by now, associated with Peter Sinclair and his Climate Denial Crock of the Week So Christy Crocks is good To Spencer, how about the catchy 'Spencer Spam'? I associate spam with Monty Python, but it also means something like 'really annoying blanket advertising (in public places), with little value'
  5. Chasing Pielke's Goodyear Blimp
    sout, I agree. The button titles are a good pointer to the content. There are plenty of people who check out here to follow up on something they've heard or read elsewhere that somebody-or-other has said ...... For a more frequent or egregious misinformer, there's probably a designated button. There's another site with 'crock' rather than slip up in its title. I've not seen any huffing and puffing about that one.
  6. Positive feedback means runaway warming
    This is on the "100ky" problem - so far multiple theories on the subject but not enough data to constrain anything to everyone's satisfaction. Modelling is focused on representing the known physical system. A sweeping approach with simple equations doesnt tell us that much about what is really happening in the system. If you regard the "CO2 lags" as handwaving, then it because its not straightforward to put down a full physical model with coupled carbon-cycle model in a blog post. The point was explain, a/ considerable uncertainty remains in tying down CO2 feedbacks and b/ what we do know makes simplistic representation unlikely. These are the problems being tackled by AR5 models in paleoclimate. For details, go to the CMIP5 site and then look for ESM (Earth System Models).
  7. Miriam O'Brien (Sou) at 17:59 PM on 19 September 2011
    Chasing Pielke's Goodyear Blimp
    The titles Christy Crocks and Spencer Slip Ups are apt, to the point and accurately signify the content. I see no need to change them at all. They are also in keeping with this site, which is to cast a sceptical eye over the 'claims' of 'skeptics'. Keep up the good work.
  8. Chasing Pielke's Goodyear Blimp
    To sum-up, the introduction in the converstaion of : - the UAH satellite data - the ad hominem fallacy fallacy about the misinformers button names is the usual red herring fallacy. Denialism is worse than one-sided skepticism : it is not scientific skepticism at all.
  9. Chasing Pielke's Goodyear Blimp
    It's a pity the course of rebuttals went the way they did. Pielke Sr. effectively thumbed his nose at the real need - accurate testimony on record with the US Congress. Maybe after collaborating on six publications together, Pielke is more than ready to go to bat for a colleague. A loyalty priority makes sense of the slippery responses. Alternatively, there may be a practical reason for some of his arguments about the UAH data at this juncture. It's the anniversary of a collaboration paper "What Do Observational Datasets Say about Modeled Tropospheric Temperature Trends since 1979?" (Remote Sensing, Sept 2010) http://pielkeclimatesci.files.wordpress.com/2010/09/r-358.pdf Maybe it was challenged in SkSc, he meant to vent then, and post-dated his day-planner wrong. Natural variability. Leave him to wallow in a devotion to the 'scientific robust' world of WUWT. He does seems attracted to the word 'robust': http://wattsupwiththat.com/2011/04/11/pielke-senior-climate-science-myths-misconceptions/
  10. Chasing Pielke's Goodyear Blimp
    Very nice summary of what's been a rather interesting exchange over the past few days. It's amazing how thin-skinned some skeptics are to scientific criticism. As I said on the other thread, calling Spencer and Christy's misinformation 'slip-ups' and 'crocks' is actually being kind to them. 'Slip-ups' in particular are usually accidental.
  11. Chasing Pielke's Goodyear Blimp
    As a lurker and admirer of this site I am pleased to suggest "Spencer Spoofs" and "Christy Chimeras" ...although more picaresque phrases could doubtless be applied, most breaching the ad hominem directive!
  12. SkS Weekly Digest #16
    Another quote, from Upton Sinclair (I think!) "You cannot get a man to believe something when his job depends on not believing it" And for 'job' we could substitute 'value system' 'sense of self worth', 'world view', 'political alignment', 'religious beliefs'....
    Response:

    [DB] Added link to Upton Sinclair quote.

  13. Positive feedback means runaway warming
    Turns out the injection-lock analogy may not be so far fetched after all. I knew I couldn't have been the first to thought of this. Here is a peer reviewed paper on the subject. Comments?
  14. Sea level rise is exaggerated
    Was my post deleted or did I just forget to press submit?
    Response:

    [DB] The moderator deleted your comment because:

    1. You have continued to focus on inconsequentially short time periods despite repeated advice to the contrary.
    2. You have still not indicated what your point in posting on inconsequentially short time periods is.
  15. Positive feedback means runaway warming
    Sphaerica/scaddenp - You both raised similar concerns. Believe me I have no illusions of building a circuit model of the climate! I'm simply trying to understand the science. I've read the links suggested, and am getting up the learning curve slowly. The feedback discussed here seemed counter-intuitive so I noodled it through until I understood the disconnect (f < 1 does not imply passive feedback as it does in control theory). Along the way I found an analogy I thought might be useful to others in similar straits so I posted it. It's not meant to be anything more than a tool to help engineers understand one tiny aspect of the puzzle. That being said, there is no reason the differential equations that describe the climate can't be reformulated as a non-linear control system problem. Such a system should be able to describe in broad strokes the major features seen in the Paleo record. The problem is they don't. They can not explain how CO2 lags temperature through the entire cycle (and please don't point me to the CO2 lags thread. Been there. I want equations not hand waving about feedback).
  16. Observations of Climate Change from Indigenous Alaskans
    agnostic: the noticeable difference between -25C and -40C is mainly the amount of heating one needs, more important, i guess, is the way the ice forms, without snow the ice becomes harder and thus f.e. changing the location for ice fishing becomes harder. coldest I've experienced is just -37C so what do I know.
  17. Observations of Climate Change from Indigenous Alaskans
    nuclearscience. I remember reading an article, (will have to go hunting) on geo engineering which talked about the difficulties. It had a lot to do with any unintended side effects. How do you engineer the planet for a specific temperature when everything has different and overlapping effects and different life times in the atmosphere, from a few days to hundreds of years. You then have opposing feedback effects etc. It is just crazy to think that we can develop that kind of control, we are more likely going to send weather crazy and then as mentioned there is the huge acidification of the oceans issue. Way simpler is to transition as fast as practicable to renewables and not put our planet through that much unnecessary stress. Much better to leave our carbon where it is, why would we want to use it all and then adjust? We may need it for different reasons in the future. Makes no sense.
  18. Positive feedback means runaway warming
    KR #44/45 - I agree that analogies can only be taken so far. They can be useful though for bringing a foreign concept into a more familiar realm. That being said, I'm surprised that I can't seem to find a transfer function based model of the climate. Its a control system, surely someone as formulated it as such. There is a well developed discipline called system identification which can derive transfer functions from auto-correlation of sampled data which would seem to be useful in this application.
  19. Positive feedback means runaway warming
    jpat - the individual orbital cycles are very regular but the sum is not so much. Furthermore, they affect climate in slightly different ways. I would be extremely cautious about pushing this too far.
  20. SkS Weekly Digest #16
    Love the toon of the week! Thanks to all for keeping up the high quality of the site.
  21. Positive feedback means runaway warming
    jpat, If I may interject with an observation, I think you are very in danger of succumbing to hammer/nail syndrome ("when all you have is a hammer, every problem becomes a nail"). You are trying to view everything in terms of your own area of expertise, circuitry. While this is easier for you, it is going to lead you into trouble. Your analogies are fine for understanding a problem initially, but you will lose track of the fact that they are only analogies, and necessarily flawed. To answer your questions and doubts I would very, very strongly suggest that you start by reading Spencer Weart's The Discovery of Global Warming -- A history. It's interesting, and you will learn a ton.
  22. Positive feedback means runaway warming
    "Why does it have to vary? The sensitivity to any particular forcing may remain constant while the forcings themselves vary." The Milankovitch forcing are very regular and of essentially constant amplitude. The sensitivity is determined by the sum of all the feedbacks so to the extent that one or more feedbacks depends on temperature or other dynamic variables in the climate, the sensitivity will change. I don't think it is controversial that the assumption of constant sensitivity is only valid over a few degrees. With regard to your other point, I think perhaps a more apt analogy would be a class of circuits called injection locked amplifiers. In and of themselves they are stable but have positive feedback. They don't oscillate because their complex poles have very low quality factor and are unable to remain on the jw axis for any period of time. However, if we inject a small periodic signal near the eigenvalue frequency, the circuit exhibits behavior very much like a phase-locked loop. Its phase trajectory tracks the input signal inside a bandwidth determined by the injection amplitude. Outside of this bandwidth, the phase trajectory variance falls as f^4. This makes them useful as filters but they are not widely employed because they have a tendency to exhibit chaotic behavior. The interesting thing about these circuits is that they behave much like oscillators in that each node in the circuit is a delayed version of the previous node (like the CO2 curve in the ice core is kind of a delayed version of the temperature). Another interesting thing is what happens when we add a constant forcing bias. The peak amplitude of the output does not change but rather the duty cycle is modified. It reaches equilibrium by modifying the symmetry of the output waveform. For instance with positive constant forcing the waveform adjusts to spends more time in the positive realm than in the negative realm but the peak amplitude remains unchanged. What got me thinking about this was a Fourier analysis I did of the Vostok ice core data. The phase noise power spectral density exhibits the same BW tracking fingerprint I saw when analyzing these injection locked amplifiers years ago. This doesn't prove anything but it is an interesting idea.
  23. One-Sided 'Skepticism'
    Dr. Peilke, sr., I have to confess that I am more than a little confused by this idea of 'balance' in science. Balance is not and never was part of the scientific process. SkS doesn't have to provide balance - it has to provide accurate representations of what is happening in terms of global climate, and to scientifically discredit work that fails to measure up. 'Balance' suggests that this should a political debate. It suggests that all opinions have equal validity and should therefore be heard, rather than analysis of scientific arguments based on evidence. If you want the science evaluated, then put it out there for critical appraisal. Your ideas should be judged on their merits, rather than a predetermined notions of ensuring 'balance'. It your science is good, you'll rightly receive plaudits for it - even from people here. As the site moderators have made clear, you are very welcome to engage in the process of evaluating the science here. After regularly visiting and reading this site for more than 18 months, I feel I can attest to the overall rigour of the site in this regard.
  24. One-Sided 'Skepticism'
    I suggest that to counter Shub's misconceptions that SkS produce a post detailing the history of the satellite record... what was known, when, and how long it took and what measures were taken before the issues were resolved.
  25. One-Sided 'Skepticism'
    What's hilarious with BEST is that it was funded by the Koch Brothers & being run by a well-known skeptic (Muller), so obviously Pielke & Watts were both expecting a "Fait accomplis". Hell Hath no Fury like a "skeptic" scorned.
  26. One-Sided 'Skepticism'
    What a load of unadulterated nonsense "Shub". I have friends & family whom I love dearly-but they have some really *out there* opinions about certain subjects-often based on no evidence-& I think those opinions are a *crock*-& I'll *TELL THEM SO*!!! They've never once thought that I was attacking them personally though. Of course, given the repugnant language that's been dished out-by skeptics-towards climate science, I think the skeptics are being incredibly *precious* & *thin skinned*. If you can't stand the heat, Shub.....
    Moderator Response: [mc] Easy on the all caps, please.
  27. One-Sided 'Skepticism'
    Shub#189: So you wouldn't agree that any scientist who claimed 'for the better part of a decade' that a dataset proved something it doesn't has not earned somewhat of a bad reputation by virtue of those claims? The criticism is of the work, not the man. To object to 'somewhat infamous' as an ad hominem attack is just silly. However, when commenters on your blog are making nazi references about SkS, that escalates from silly to outrageous. If you would assume a position of moral outrage, clean your own house first.
  28. One-Sided 'Skepticism'
    Marcus, Thanks.... I appreciate you wading into that venue to dig this up. Dave
  29. One-Sided 'Skepticism'
    [To Philip Chantreau moderator] You state: " this thread is about Dr Pielke's accusations of ad-hominem and one sided skepticism." and "You were asked to provide an example of real ad-hom committed by SkS and you have so far failed to respond." On the 14th Sept, this website carried an article, that is still extant, that contains the statement: "and it's also entirely possible that the satellite temperature data is still biased on the cool side. Christy and Spencer are somewhat infamous for claiming for the better part of a decade that the UAH satellite data proved the climate wasn't warming as fast as models projected (sound familiar?), until research by a number of scientific groups [including Christy and Spencer themselves] discovered errors in their data analysis which accounted for most of the discrepancy." The article in question deals with the disparity between the global troposheric temperatures measured by satellite, and those estimated by models. In the backdrop of the open, transparent availability of the methods used to derive satellite temperatures, the author speculates that a cool bias may still exist in the UAH record, stemming from a alleged deficiency on Spencer and Christy's part. He terms this an "infamy". Pielke Sr on the other hand, characterized the same process of error-detection and correction in the satellite record as a learning exercise and one, in which Spencer and Christy participated responsively. Indeed, the ability of a scientist to quickly admit to errors and provide for corrections advances science and this example has been documented, also, at this very website. There is a contradiction between these two positions. Pielke Sr of course has taken stance firmly behind the latter position. Skepticalscience must decide whether Spencer and Christy are good scientists because they correct and maintain the UAH record, or they are bad scientists because there were errors in the satellite record. The post at the top of this thread claims that skepticalscience website never questioned the UAH satellite record, in order to bolster its labelling of scientists' activities. The passage quoted above, however, does exactly the same. It is listed in the Christy Crocks series of articles. Pielke Sr criticized derogatory blog posts and news items, resorting to labelling of scientists and their activities, which also questioned the UAH temperature recordkeeping of Spencer and Christy. The present post denies having done either. It is clear however, from examining the skepticalscience post, titled, "Santer et al. Catch Christy Exaggerating" published on the 14th Sept, that neither can be denied. The article did make claims based on insinuations about the UAH record, and did classify the article as a "Crock". This is the example you were seeking me to point out. This is the example you demanded Roger Pielke Sr point out to you. Thanks.
    Moderator Response: [Albatross] Shub, you are not recalling events correctly and are trying to twist the argument around. Pielke, for some reason, tried to implicate SkS in someone elses' harsh critique of Spencer and Chrsity's treatment of the UAH record. He was conflating different issues in his attempt to smear SkS. For the record, Dr. Pielke seems to be applying selective memory when it comes to recalling how events actually transpired surrounding the UAH MSU data. Read this article by Spencer and Christy from October 1997. In it Spencer and Christy claim: "In theory, one could argue that the computer models are accurate, and that the real measurements have some problem. However this is not the case." and "The result is that the satellite temperature measurements are accurate to within three one-hundredths of a degree Centigrade (0.03 C)". They said this even though at the time others working on the satellite knew that there were unresolved issues and would not have been nearly so brazen or confident, and it took until 2005 until most for the issues plaguing the satellite data were identified and corrected properly. And let us not forget the work of Hurrell, Trenberth, Wentz, Mears, Fu, Johanson, Warren, Seidel, Vinnikov, Grody, Zou and Prabhakara and others who made invaluable contributions to identifying and fixing problems with the satellite record.. There is a detailed discussion of the satellite product by Scott Church I recommend that you read it. SkS does not have to decide anything, rather you and Pielke need to decide what is more important, covering up misinformation or standing up for science and truth. Spencer and Christy run into trouble because of they do not practice self-skepticism and because they choose to misrepresent the science, distort the science, misinform the public, politicize the science, speak to thinks that they are not qualified to speak to (e.g., economics, DDT), and in Christy's case, mislead Congress. But defend their bad behaviour if you must and insist.
  30. Positive feedback means runaway warming
    I think that climate sensitivity has to vary. Consider two extremes. If you melt all the ice pack, then the albedo feedback component practically disappears. Second consider an iceball earth with just enough solar input and CO2 start a melt the ice at the tropics. At point water vapour enters the atmosphere where it wasnt before. In this scenario, climate sensitivity has to be extreme. I think this is reason (beside the measurement errors) for the wide of range of sensitivities from paleoclimate studies. Carbon-cycle modelling still has a lot of uncertainty with many different ways to replicate known data. However, I dont think any of them would give a linear or log-linear response of atmospheric CO2 to temperature.
  31. Observations of Climate Change from Indigenous Alaskans
    kdkd, Sorry. I get cranky when people finally shed their denial of the science, but then put on rose-colored denial-glasses to imagine maybe it won't be so bad after all, or that there's an easy way out and they don't have to make any sacrifices at all today.
  32. One-Sided 'Skepticism'
    This comment stands out most strongly: "With his testimony, Dr. Muller has totally destroyed any credibility he might have had with me. He might be able to rebuild it by explaining his strange numbers. But to give that kind of erroneous testimony, not in a random paper he might written quickly, but to Congress itself, marks him to me as a man driven by a very serious agenda, a man who doesn't check his work and who pays insufficient attention to facts in testimony. I had hoped we wouldn't have another temperature record hag-ridden by people with an axe to grind -- foolish me." I wonder if Pielke Sr thinks this is appropriate language to use against Professor Muller? After all, its much more harsh than the criticisms leveled against Christy & Co at this site!
  33. Positive feedback means runaway warming
    jpat#47: "Is climate sensitivity constant or does it vary" Why does it have to vary? The sensitivity to any particular forcing may remain constant while the forcings themselves vary. For example, as more CO2 enters the atmosphere, that forcing increases with constant sensitivity. FWIW, I wonder if you've considered a circuit analogy from a simpler time: Hartley and Colpitts oscillators exploit feedback without necessarily running away.
  34. One-Sided 'Skepticism'
    Hey Dave123. Sorry for the delay in replying to your message. The 2 posts in question are here: http://wattsupwiththat.com/2011/03/06/briggs-on-berkeleys-best-plus-my-thoughts-from-my-visit-there/ This was *before* Muller's testimony on his preliminary results. Now here is the follow-up *after* the testimony: http://wattsupwiththat.com/2011/03/31/expect-the-best-plan-for-the-worst/#more-37009 In particular read some of the vicious attacks from Watts' followers. It seems that "skeptics" don't like having their skepticism challenged-even by one of their own!
  35. Observations of Climate Change from Indigenous Alaskans
    nuclearscience. The issue for your friend now gets more complicated. CO2 is not going into the atmosphere alone. What acid/base balance will the ocean be at by the time we reach this apparently benign state of converting geological solid carbon fossils into gaseous carbon compounds? In one way, your friend is right(-ish). We've been accelerating a geological process. The geological method of converting fossil carbon compounds into gaseous ones is by volcanic activity. The geological method of reabsorbing that carbon is by reactions (weathering) of some kinds of rocks. (The biological processes cannot do this on their own.) So we can stop blowing up mountains or quarrying huge holes to release carbon and start doing the same thing to different rock formations to absorb it. Seeing as our petroleum use each year amounts to 93 million years of sequestering carbon, we've got quite a lot of rocks to blow up already. Don't know how ready your friend is to start considering ocean acidification, but you've brought him this far already. You might see how ready he is for the next step.
    Response:

    [DB] Fixed text (the Preview function works in lieu of a 2-minute edit window).

  36. Positive feedback means runaway warming
    "The Milankovitch forcings last for millenia, which allows time for various feedbacks to take effect...The Wiki on this is actually fairly reasonable." From the Wiki: "Each glacial period is subject to positive feedback which makes it more severe and negative feedback which mitigates and (in all cases so far) eventually ends it." And yet in this tread (see #54), chris accuses me of making an "evidence free assertion" when I tried to make that very point. Which is it? Is climate sensitivity constant or does it vary as negative feedback(s) kick in at the extremes?
  37. Sea level rise is exaggerated
    189, Steve Case, So what? What's your point? That scientists make adjustments as data and techniques improve? Did CU adjust their rate using a short range, or did they adjust their rate based on new data that extended a reasonably long range for even longer?
    Response:

    [DB] "What's your point?"

    The point Steve has been trying to make is one of conspiracy and fraud on the part of UCAR.  However, he is reduced to making them via veiled insinuations, because he knows any more open accusations won't survive moderation.

    It has become very tiresome.

  38. Positive feedback means runaway warming
    I think I have an analogy that maybe helpful to those like me who come from an engineering background and have trouble putting the feedback discussed here into a more familiar context. Consider a circuit comprised of a voltage source connected to a resistive divider. Assume the divided voltage is our output node. To this output node we connect the control port of a voltage controlled voltage source of gain b whose output is connected to the output node through a series resister. This is our feedback path. Assume all resisters are 1 ohm. If b is zero the output voltage is simply one third the input voltage. As b is increased from zero to 1, the output rises from vin/3 to vin/2. Thus we see a "gain" of 1.5 compared to the no feedback case but in both cases the forcing (vin) is attenuated. With b=0, the thevenin impedance looking into the output node is 1/3 and therefore the output power density is 4kT/3 W/Hz. With b = 1, the thevenin impedance rises to 1/2 and so too does the power density, to 2kT. This indeed we can see an increase in variance with feedback gain < 1. Finally note that b in my analogy is not the same as f in #37. In the example, b could actually vary between 0 and 3, (corresponding to 0<=f<1) before the circuit became unstable. However, to get actual gain (in the normal sense of the word, i.e. an output greater than vin), b must be greater than 2. That is, to get actual amplification requires active feedback, as expected.
  39. CO2 lags temperature
    Firstly, GHG arent the only forcing. Our theory of climate states that climate will go with the sum of all forcings. If you want to me to "show you" a graph where CO2 is changing climate then you need time when GHG is dominant forcing. The modern era since 1970 is one immediate example. The PETM would be another. A more rigorous phenomenological approach would be to examine temperature as a function of all forcing, eg see Benestad and Schmidt 2009. But for the glacial cycle, the problem is more one of arithmetic. The NH solar forcing and albedo are not strong enough to explain the temperature response by themselves. This was one of the original objections to Milankovitch theory. Furthermore, why is a NH forcing able to cool the SH, whereas same forcing in SH doesnt have an effect? The reason being that the CO2 feedback is global rather than hemispheric. On top of this, you have difficult problem of explain why the directly measurable effect of GHG on surface irradiation does not change temperature if you wish to discount GHG as having an effect on climate.
  40. Sea level rise is exaggerated
    # 188 Sphærica Yes the time period is short and Colorado U adjusted the rate of sea level rise at least three times over that stretch.
  41. Observations of Climate Change from Indigenous Alaskans
    3, nuclearscience, You might point out to your friend that aerosols are actually responsible for currently holding temperatures down (or so Hansen theorizes), but that aerosols only stay in the atmosphere for a few years. And even so, the vast increase in aerosols resulting from a billion Chinese creating 2 new coal plants a week is only slowing down the warming, not stopping it. Lastly, such an effort would require the continual injection of aerosols into the atmosphere. What might that source be if we've consumed all available carbon on the planet? And, more importantly, where will the energy come from to power such an effort? Renewables? If that's the case, then why the heck not switch now?
    Moderator Response: kdkd - removed an ad-hominem to make an otherwise useful comment acceptable to the comments policy
  42. One-Sided 'Skepticism'
    I go away to have dinner and come back to find that others have made my point for me. However, as I either took Shub's bait or felt that my point was more on topic than it appears to have been, I'll refrain from further model discussions unless they're somehow more clearly on topic. My apologies.
  43. Observations of Climate Change from Indigenous Alaskans
    This article highlights the changes probably everyone will eventually need to face. I fear for us in the States, its more about dealing with +100 deg F weather for extended periods, rather than warming from deep freezes. On a slightly related note, I have had serious debates with a friend at work recently over CO2 and climate change. My friends opinion has changed over the months (I guess that is progress) from denial, to realizing that there is warming, that it is manmade, but now that progression has hit a significant snag. He now claims that humans can engineer the temperature rise away by introducing aerosols into the upper atmospshere or some other technique that is far cheaper than addressing rise CO2. His argument that CO2 levels will plateu with the consumption of all available carbon mass on the planet, and we will be able to engineer away the temperature increases if they become a problem. So it looks like there's a new potential climate myth in the budding: We can fix global temperature by geo-engineering. Are there good peer reviewed articles that critic the geo-engineering argument? What are the downside risks of massive climate engineering? As always, thanks for the informed debate!
    Moderator Response: [John Hartz] Go to the Yale Environment 360 website and put "geo engineering" into the site's search box. You will get a list of links of a number of excellent articles on this topic.
  44. One-Sided 'Skepticism'
    Shub, I'm still at a loss. My point was that a measured assessment would not have proposed a significant difference existed between models and the UAH data. At the very last it would have made an effort to compare apples to apples and assess statistical significance before making a statement to congress. Christy's conclusion was biased and statistically unjustified even if it doesn't meet your own rather arbitrary threshold of significance. Satellites don't measure temperature directly. UAH uses microwave spectra to infer temperature. That's not straightforward. In fact, you could say it requires a model. Maybe not one as involved as a GCM, but still challenging. You're right that the model should match observational data to the extent possible, but potential errors/noise in the observational data, especially one as compex as satellite data, need to be considered. A model could get the prediction perfect and still disagree with the observations if there is noise or bias in the observational data set. So why not acknowledge that complex observational dataset could have problems that contribute to a discrepancy with model predictions? I still don't see the supposed ad hom in pointing out that Christy should have.
  45. Climate Sensitivity: Feedbacks Anyone?
    I can not think how I missed this important article. What it points out is that for the first time, anthropogenic CO2 emissions have triggered fast and slow feedbacks, that “slow” feedbacks are occurring faster than expected and are not appropriately included in models aiming to forecast climate change. All very true! The article notes that …”In Antarctica, an amount of ice worth 20-25 m is rooted below sea level and held back by ice shelves.” If this refers to the WAIS, its thawing could raise sea level by 5-7 m rather than 20-25 m. In regard to the albedo slow feedback, I would note that the greatest loss of sea ice area occurs in summer enabling exposed ocean water to increase absorption of solar energy but that in winter ice mass continues to be eroded by warmer water insulated by the ice from the very much colder atmosphere above it. It’s a lose-lose situation. Lastly, I note that the article refers to CO2 as a slow feedback – which of course it is – but does not mention the elephant in the room, the far more potent, much larger and very dangerous release of CH4 embedded in permafrost which has now begun thawing. That is a slow feedback which I would argue is about to accelerate. Or is James Wright’s reference to CO2 a metaphor for CH4?
  46. One-Sided 'Skepticism'
    Philippe#182: True enough, but Shub's taking the scattergun approach typical of one-sided (biased) 'skeptics'. If he wants to discuss modelling, there are threads for that.
  47. One-Sided 'Skepticism'
    Shub: "Satellites measure temperature. Models produce estimates of temperature. It is pretty straightforward. Measurements don't exist to support models." Shub, you are demonstrably wrong (see scientific scholarship -- all of it). Any theory is a model based on observed, measured phenomena. Continued measurement directly serves the confidence of models. If temperatures (ocean, surface, and atmosphere) trend away from current GCMs, theory (and the models) must change. Perhaps you meant to say something more nuanced.
  48. Philippe Chantreau at 09:44 AM on 19 September 2011
    One-Sided 'Skepticism'
    Shub, this thread is about Dr Pielke's accusations of ad-hominem and one sided skepticism. His own blog post was not about the science but about those accusations, including a ridiculous assertion that SkS tried to undermine the UAH data set through the use of ad-hom. He was repeatedly asked to substantiate that accusation and was unable to do so. You made accusations of ad-hom yourself. You were then asked several times to cite exactly what "name" was Spencer or Christy called and have been equally unable to substantiate. If you want to talk about anything else go do it on the appropriate thread. You were asked to provide an example of real ad-hom committed by SkS and you have so far failed to respond. If you can't substantiate, you should refrain from further comments. You are not going to distract anyone by trying to change the subject, we are part of the reality based crowd here. Don't be surprised if your further off-topic posts on this thread are deleted, Dr Pielke was given unusual latitude in this matter and it won't happen again to him or anyone else. Muon thank you for the graphs, but they are also off-topic. They would be welcome and more useful on the appropriate thread, where Shub's comments on the same topic should be moved.
  49. One-Sided 'Skepticism'
    Shub#173: "Measurements don't exist to support models." You might want to qualify that a bit: measurements don't exist to support some models. Looks pretty clear that measurements do indeed support some of those models; the rest didn't get it right. Did you ever wonder why?
  50. It hasn't warmed since 1998
    michaeld#115: "Would it be possible to quantify all these effects?" Done. See Tracking Earths Energy and any of the many sensitivity threads, for example here. But average temperature (actually temperature anomaly, in comparison to a standard base period) is important because it is a directly observable change. But more important than the year-to-year, month-to-month anomalies is the temperature trend. Since the mid-70's that trend is up.

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