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L. Hamilton at 03:54 AM on 20 June 2012Scientific literacy and polarization on climate change
That's a well-known pitfall for survey research, called "response set bias." It's something to always keep in mind when designing a survey, or when looking at data from a survey designed by others. My "just right" example above, for instance, has been carried on two different surveys, neither of which said another word about ice or polar regions. Despite different samples (one statewide and one national) and otherwise mostly different questions on each survey, they produced similar results. These conclusions I'm talking about are pretty robust. -
Eric (skeptic) at 03:40 AM on 20 June 2012Scientific literacy and polarization on climate change
L. Hamilton, thanks for the details. I agree the second question is just right and a "no brainer". My only quibble with the observation in your last sentence is that those similar correlations may come from the respondent's view of the questions as a whole. Will the respondent answer in "contrarian" ways because some questions (not your latest example but the prior one) appear oversimplified? If that is the case then the correlation is not from respondent qualities to each question but from respondent qualities to the whole set of questions. -
adamski5807 at 03:25 AM on 20 June 20122012 SkS Weekly Digest #24
Feeling so helpless and useless at the moment. Quite depressing. Did you guys read this?? Game Over For The Climate? 'Whatever happened to the green movement? It’s been 50 years since the publication of Rachel Carson’s classic Silent Spring, a powerful book about the environmental devastation wreaked by chemical pesticides. Since then we’ve had the rise and fall - or at least the compromised assimilation - of green groups such as Friends of the Earth, Greenpeace and Forum For the Future. Last week, the Independent marked the half-century with a well-meaning but frankly insipid ‘landmark series’ titled ‘The Green Movement at 50’. But there’s a glaring hole in such coverage; and, indeed, in the ‘green movement’ itself: the insidious role of the corporate media, a key component of corporate globalisation, in driving humanity and ecosystems towards the brink of destruction" http://www.medialens.org/index.php?option=com_content&view=section&layout=blog&id=1&Itemid=50 -
Bernard J. at 02:19 AM on 20 June 2012Arctic sea ice takes a first nosedive
Back in the day when frosts were common here*, I used to watch the frozen puddles go from being almost completely sheeted in ice to clear water in just a matter of minutes, once the mornings had warmed sufficiently. So it will be, I predict, that Arctic summer sea ice extent will appear to be still 'relatively' high for some small number of years into the future, but following a few warm summers that summer sea ice will spectacularly disappear - like the thinning ice used to do on the puddles on the west side of my house. Of course, anyone who follows Arctic sea ice volume (or thickness) rather than area/extent will not be caught off-guard, but I am sure that come the time there will be loud brays of faux surprise from those who currently claim that there's nothing more happening than a breezy shifting of a few burgs. [*Prior to the last decade it was usual in my area to have had by this time of year, as the austral winter approaches, about a dozen or so of of those teeth-setting crunchy frosts. So far this year we've had nothing even remotely resembling ice. There have been other changes too - to avoid going off-topic, I'll just note that I commented about them on Deltoid's June Open Thread, at tmie-stamp June 15, 12:57 pm.] -
thepoodlebites at 02:02 AM on 20 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
For Figure 2, the above statement "His plot shows the purported 5-year running average temperature around 1998 as hotter than at any later date to present, which is not true of any surface or lower atmosphere temperature data set" contains a link to a "woodfortrees.org" plot. But if you use Roy Spencer's website, the 13-month running mean clearly shows that 1998 and 2010 are tied (+0.4)C. So the assertion that 1998 was not hotter than at any later date is a bit misleading. Both 1998 and 2010 were peaks in global averaged temperatures in response to El Nino events. -
vrooomie at 01:42 AM on 20 June 2012Glimmer of hope? A conservative tackles climate change.
Lloyd@17, truer words I have not seen written here. I am usually fairly centrist, with a left-leaning tendency on social issues. The "right" has taken upon itself as a Crusade, to be against *anything* the "left" are for, irrespective of its basis in fact. As an earth scientist (geologist) with a strong interest in climate change, I find it increasingly and frustratingly difficult to use reason and logic with any denier. "I think conservatism [in the USA] has become obsessed with attacking the left and will attack most things that the left supports just because the left supports them. Libertarianism is threatened by the market not having an answer to AGW and hence is looking for reasons to believe it does not exist. Denialism is a club created by libertarians that has been enthusiastically adopted by many conservatives as something to beat the left with. With the libertarians the matter is what they are protecting. With conservatives it is part of the general attack on the left." -
Adam C at 01:40 AM on 20 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
He lost me at "150% wrong". There's no evidence of scientific literacy there at all. -
shoyemore at 01:25 AM on 20 June 2012Arctic sea ice takes a first nosedive
Neven, Great post & blog. I notice that JAXA seems to have revised downwards the big breaks they were posting for the past few days, and the Arctic Oscillation has turned positive. You have provided an excellent answer to the question I was going to ask! -
John Hartz at 01:20 AM on 20 June 20122012 SkS Weekly Digest #24
Note: This thread is now open to a discussion of the ongoing Rio+20 Conference . -
dana1981 at 01:09 AM on 20 June 2012Hansen 1988 Update - Which Scenario is Closest to Reality?
poodle - forcings are independent of climate sensitivity. The actual forcings are based on GHG concentration observations, linked in the Figure 3 caption. I suggest you read the Solheim post because the concepts you are confused about are explained more there, particularly in the last section. -
L. Hamilton at 23:35 PM on 19 June 2012Scientific literacy and polarization on climate change
"But to my eye the presence of a number of simplifications implies the possibility of oversimplification." Eric, survey questions have to be simplified, though it's a matter of degree. To my ear this question is too simple: 'Would you say the polar ice caps have gotten larger or smaller over the last 25 years?' whereas this one is just right: 'Which of the following three statements do you think is more accurate? Over the past few years, the ice on the Arctic Ocean in late summer ... Covers less area than it did 30 years ago. Declined but then recovered to about the same area it had 30 years ago. Covers more area than it did 30 years ago.' But either one correlates with respondent knowledge, politics and background characteristics in very similar ways. -
L. Hamilton at 23:23 PM on 19 June 2012Scientific literacy and polarization on climate change
"What would be really interesting would've been to divvy the group up into quartiles for example, to see if scientific literacy correlated differently with the understanding in "the middle" of the political spectrum...In fact I'm sure they could've done that though I dont' see it on glancing through the paper." I just noticed the lead-off question by Utahn; it seems worth mentioning that's exactly what Figure 1 in our paper does. -
thepoodlebites at 22:49 PM on 19 June 2012Hansen 1988 Update - Which Scenario is Closest to Reality?
What exactly are the "Actual" forcings based on in Figure 3? What climate sensitivity to CO2 doubling are you using, 3C? My point is that the satellite-based observations are clearly not following Hansen's Scenario A or B, even falling below Scenario C through May 2012. The empirical evidence suggests that model-predicted forcings are too high. (-snip-).Moderator Response: [DB] Moderation complaints snipped. -
curiousd at 21:50 PM on 19 June 2012Lessons from Past Predictions: Hansen 1981
Hello All, Thanks for all the help, everyone! I now have a glimmer of understanding. The idea of a "transient response" due to the ocean to even an apparently short term feedback (such as keeping the relative humidity constant) is crucial. And then on top of that you also have long term effects such as the ice albedo thing which will take much longer. I will next focus more on understanding the recent work where Hansen - I guess - takes the ancient record and obtains the climate sensitivity by fitting the old data. It is now conceivable to me that the fact that they got basically the same sensitivity with the 1981 model was slightly fortuitous, but probably only slightly. -
Bernard J. at 20:35 PM on 19 June 20122012 SkS Weekly Digest #24
The thing with "sustainable development" in natural systems, especially if they're living systems, is that at some point the "development" involves a greater or lesser degree of senescence. At the system level, development (which is analogous to complexity) is asymptotically constrained by energetic input into the system. -
Eric (skeptic) at 19:15 PM on 19 June 2012New Research Lowers Past Estimates of Sea-Level Rise
scaddenp, technological progress is always speculative but it is always inevitable. I'm not sure how you can make a thermodynamic argument because as you know, it is chaotic system control problem. The "stability" of the circumpolar circulation is more of a persistence than a stability. The presence of these lows: http://ams.confex.com/ams/pdfpapers/20231.pdf means that natural changes and/or GHG responses are starting to affect the weather and weather control can help that along. As this paper shows http://soap.siteturbine.com/faculty/faculty_files/publications/1082/Kreutz_JGR_2000.pdf the Amundsen Sea low is currently the dominant feature for much Antarctic weather and moisture flux (as opposed to the Antarctic high). The rest of Antarctica will require transitory lows to penetrate the otherwise persistent (not stable) circumpolar flow.Moderator Response: [DB] This line of discussion has digressed and is OT for this thread. Please find one of the solution threads if you wish to continue this. Thanks! -
scaddenp at 12:03 PM on 19 June 2012New Research Lowers Past Estimates of Sea-Level Rise
Just for further clarity - my understanding of the speculative bit was that some large-scale processes (eg hurricane formation, monsoon path, maybe even ENSO timing) ultimately stem from small bification in chaotic system. However, much of climate is large-scale stable phenomena, bound by thermodynamic constraints. Eg changing timing of an ENSO event might be possible but not holding one back. The circumpolar system would another major stable system. The high pressure systems sitting on the poles are there because its cold, just as low pressure system dominate the tropics. No interference with dynamical systems can change this. -
scaddenp at 11:54 AM on 19 June 2012New Research Lowers Past Estimates of Sea-Level Rise
Wild speculation about what might be possible in the future without a single line on the thermodynamics does not translate into "a reason not to worry about sealevel". You assumed "control" of micro processes would allow you violate that thermodynamics boundary conditions which I dont think the author implies at all. Inferring from that discussion that it was "inevitable" to gain weather control, is frankly amazing. The science paper discusses that increasing precipitation (from warming) was increasing snow cover, but as it turned out from the GRACE measurements, the paper was also wrong. There is already increased ice loss from edges, so you have net ice loss. If you want increased precipitation, then you have to move more warm moist air onto Antarctica from surrounding ocean. Where is most of that going to precipitate? Gains would be a passing phenomena only, especially if that precipitation starts falling as rain (making it a effective heat transfer mechanism) eg reported here. I didnt ask my usual question, as it is clear that a heatpump of the magnitude required (the only solution that make thermodynamic sense) would be fundable by the only by those responsible for the emissions. -
Bob Loblaw at 11:48 AM on 19 June 2012Lessons from Past Predictions: Hansen 1981
curiousd: First, I'd like to say that your process of asking questions and trying to sort out answers is highly encouraging, and I wish more people that come here to ask questions did it in this manner. The help that you are receiving is an example of the kinder, gentler reaction that people get from the regulars here when they are really interested in learning. ...but to get back to Hansen 1981... I think there is a bit of confusion when Hansen et al talk about different models. In essence, they are really just using one model, but they are making different assumptions in doing simulations with the model, which lead to (slightly) different results. The model that they use is a one-dimensional radiative-convective model, and it might help to read the early descriptions of such models, examples of which are in these papers: Manabe and Strickler, 1964. Manabe and Wetherald, 1967. These papers give a much more detailed description of what is in such a model, including examining many of the assumptions that Hansen et al make in looking at model sensitivity. To try to explain a bit more, with regard to the points you make in #40: a) the main purpose is to examine the effect of changing C02, and it is possible in a model to alter CO2 and prevent the model from changing anything else that would classify as a "feedback", so that is how the CO2-only sensitivity is determined. b) a radiative-convective model does not contain a water cycle, so it cannot dynamically determine an appropriate atmospheric water vapour content independently. Consequently, an assumption is required. One assumption would be to hold water vapour constant (i.e., no feedback). Manabe and Strickler covers this. Manabe and Wetherald extended this work to cover the case of keeping relative humidity constant, which leads to increasing absolute atmospheric humidity as the temperature rises (i.e., feedback is present). The assumption of constant relative humidity is reasonable, and many more sophisticated models and subsequent measurements in the past 30 years support this as a good approximation. c) the moist adiabatic lapse rate relates to the rate at which temperature decreases as altitude increases in the troposphere. A radiative-convective model does not include directly-calculated atmospheric motion (it's only one-dimensional!). The models details are in the radiative transfer calculations, but if that was the only thing done, then the model would have an extremely high temperature gradient in the lower atmosphere - unrealistic. Look at Manabe and Strickler's figure 1. A radiative-convective model compensates for this by doing a "convective adjustment" to reduce the gradient to something close to real observations, assuming that convection (vertical mixing) will be doing the required energy transfer to overcome the extreme radiation-drive gradient. Hansen et al's "model" 1 and 2) used the normal observed atmopsheric lapse rate of 6.5 C/km (i.e they force the model to match this), while simulations with the "moist adiabatic lapse rate" (MALR) let the model's lapse rate vary a bit. The MALR is the rate at which rising air cools when condensation is occurring (which releases energy and slows the cooling), and it varies slightly with temperature (feedback!). You can read more about lapse rates here: Lapse Rates Manabe and Strickler, and Manabe and Wetherald give more discussion of this, too. d) [although you didn't call it d)] Cloud heights. Again, a radiative-convective model does not include dynamics that will allow it to calculate clouds independently. Clouds are there as objects with optical properties, and specified altitudes. Under a changing climate simulation, you can leave them as-is (no feedback, Hansen's models 1 and 2), or you can make assumption about how they will move or change - e.g., assume they'll form at a new altitude with the same temperature as before (generally higher) (Hansen's model 4), etc. All these assumptions will lead to the model(s) having different sensitivities. Hansen did include albedo changes in models 5 (snow/ice) and 6 (vegetation). -
Eric (skeptic) at 11:34 AM on 19 June 2012New Research Lowers Past Estimates of Sea-Level Rise
scaddenp, your definition of catastrophic SLR seems reasonable. This idea is not a reason to "do nothing" but one reason among others not to worry about sea level. The paper shows positive ice mass without any intervention, not what you describe. I don't describe this as hope but the inevitable complete control of nature from macro to micro. The question you would normally ask me is who pays for these measures. Part of my answer is here but admittedly will work better for CCS than weather control. -
scaddenp at 10:38 AM on 19 June 2012New Research Lowers Past Estimates of Sea-Level Rise
Eric, this would have to be the most extraordinary display of hope that I have every seen. None of the required technologies are even on the horizon so why do you believe that could happen before "catastrophic sea level" rise. (I'd define sealevel rise of 10mm/yr as catastrophic - what is your definition?). Furthermore, the idea that moving precipitation to Antarctica also means that you are moving heat to Antarctica as well. The isolation of Antarctica by circumpolar ocean and atmospheric currents is what is keeping it cold. You could get short term growth in central regions and even faster loss on the margins. The smart strategy is hope something good helps but act on the basis of what is likely. You cant be seriously proposing this as a reason for doing nothing? -
Eric (skeptic) at 09:45 AM on 19 June 2012New Research Lowers Past Estimates of Sea-Level Rise
To mitigate sea level rise (possibly completely) we just need to control the weather to dump moisture on the Antarctic ice sheets like nature does http://www.sciencemag.org/content/308/5730/1898.short. Control of weather, e.g. 5G_2002_Weather_Hoffman_February_2002 will happen well before catastrophic sea level rise takes place. This would not mitigate more acidic oceans, etc. -
Eric (skeptic) at 09:01 AM on 19 June 2012Scientific literacy and polarization on climate change
L. Hamilton, thanks for the explanation. I guess the fact that it is just wording in a survey means the questions can be simplified. But to my eye the presence of a number of simplifications implies the possibility of oversimplification. -
Bob Lacatena at 08:33 AM on 19 June 2012Temp record is unreliable
ciriousd, The difficulty is that it is no easier to measure the total radiation differential (energy in, energy leaving, over the entire surface of the earth) than it is to directly measure a "global mean temperature." Beyond this, on any one day the imbalance may be in one direction, then another. In particular, counter-intuitively, while a La Niña appears to cool the planet (global temperatures drop) it is in fact warming the planet (because the total energy level of the system has not actually changed, but the atmosphere is radiating less to space, and therefore warming more quickly). Things are further complicated by the need to translate the energy imbalance (measured in W/m2) to some sort of rate of temperature increase. That's pretty much impossible, because how the energy sorts through the system (air, ocean, ice) is just too complicated. So, I'm afraid your simple 3 step approach does no better than simply proving that the earth is warming. It still comes down to a complex interpretation of complex observations of values that vary wildly over both time and three-dimensional space, and yet must be averaged together to get a coherent set of numbers (and trend). -
Bob Lacatena at 08:28 AM on 19 June 2012Lessons from Past Predictions: Hansen 1981
curiousd, Look at it this way. The direct response of temperature change to a doubling of CO2 is a log function. For every doubling of CO2, you increase the temperature (directly, by CO2 alone) by 1 degree C. This is based on the physics, I believe, but I can't find a straightforward explanation for why. Climate sensitivity has to do with how much extra warming you get per degree of warming from a forcing (in our case, doubling CO2, but you could also get it from the equivalent change in solar output or other factors). That is a linear multiplier. When you talk about climate sensitivity, you are talking about specifically that linear multiplier. Double CO2 --> 1˚C increase direct --> times 3˚C climate sensitivity --> total temperature increase. The two are separate. Doubling CO2 (or increasing solar insolation, or whatever) is a "forcing." This forcing is multiple by feedbacks. How much it is multiplied is known as "climate sensitivity," and while it is useful to put a linear scalar factor on that, the reality is that doing so is a useful simplification of a complex system. -
dana1981 at 07:09 AM on 19 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
MA @6 - I did use the F&R trend of 0.17°C per decade in comparing to the Hansen model-projected warming. Bear in mind this is a very rough climate sensitivity estimate, since we're looking at transient temperature changes right now, but talking about equilibrium model sensitivities. -
curiousd at 05:26 AM on 19 June 2012Temp record is unreliable
Hi, I can think of another approach (possibly) to combating the folks claiming its not getting hotter here on the earth, and to do this for an audience. Has the advantage that you don't have to mess with a bunch of different graphs, contrasting Artic to Antarctic, etc. 1. Actually demo the water going into a funnel with a hole and coming out a stopcock which can be closed slightly (analogous to more CO2). As Hanson point out, and is evident from Toricelli's theorem, the water will slowly rise to a new level until the input flow equals the output flow.I am about to make one of these things. 2. Then I say " Maybe thousands of smart people all over the globe are measuring the energy input coming into the earth ,and also the energy leaving. And guess what? The power coming in exceeds the power going out. Its like the funnel with a larger rate of flow coming in than is going out the hole" 3. Therefore, the temperature of the earth is rising. Q.E.D. Whaddya think? -
KR at 05:14 AM on 19 June 2012Hansen 1988 Update - Which Scenario is Closest to Reality?
thepoodlebites - The discussion here is regarding the Hansen 1988 scenarios, A, B, and C, not the more recent IPCC scenarios. Aside from that, I cannot make out what your objection is. -
MA Rodger at 05:02 AM on 19 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
Should we not be factoring in the ENSO, insulation & volcanic effects (as per Foster and Rahmstorf 2011)? Jan-Erik Solheim's "whopping 150% wrong" pronoucement, show here to be actually "about 40%," would thus shrink further still to something like 20% and also suggesting climate sensitivity is (worryingly) somewhat higher than ~3.0°C. -
dana1981 at 04:55 AM on 19 June 2012Hansen 1988 Update - Which Scenario is Closest to Reality?
thepoodlebites @7 - I don't follow what you're trying to say. There is no Scenario C in the IPCC SRES, and we're talking about Hansen's emissions scenarios here anyway. -
thepoodlebites at 04:52 AM on 19 June 2012Hansen 1988 Update - Which Scenario is Closest to Reality?
Why use predicted forcings instead of predicted/observed temperature change for IPCC scenario C? Predicted forcings assume what is being debated. I don't understand the reasoning here, please see IPCC scenario C. -
michael sweet at 03:16 AM on 19 June 2012Lessons from Past Predictions: Hansen 1981
In this article in press Hansen discusses estimates of climate sensitivity over a large range of past climates. The climate sensitivity varies somewhat depending on the surface conditions. Hansen gives references to other papers that make similar estimates. When I said "Few people seem to care if all the great cities of the world are gone in 300 years." I did not mean to include posters at Skeptical Science. -
Dennis at 03:10 AM on 19 June 2012Glimmer of hope? A conservative tackles climate change.
ralbin @15: The point you're making follows up nicely with what I was asking Tom. There are precious few conservatives left in the USA who are willing to disgree (in public at least) with their bottom line argument that government can do nothing right. It's become an ideological litmus test for them that didn't exist twenty years ago. Hence, people like Adler and Wehner are few and far between. And I would bet that they don't get much funding for their work from self-identified conservative sources. A good example of type of person who once used to be considered reliable to at least recognize facts and offer a conservative response to them is George Will. But look at how he gets smacked down for misuse of facts (e.g., Arcic ice, the 70's "consensus") when he does try to deal with science. -
michael sweet at 02:54 AM on 19 June 2012Lessons from Past Predictions: Hansen 1981
Curiousd, "The only calculations I am doing is taking the climate sensitivity for the various effects as calculated by Hansen, et all, and plugging into C2/C1 = 2 ^ (t/tsensitivity). What is wrong with that? " The fast feedbacks include the time it takes for the ocean to reach equilibrium with the new atmospheric temperature. This is difficult to estimate, but shall we say 90% of equilibrium after 40 years. You need to take into account that the ocean cools off the atmosphere until it reaches equilibrium. The ocean has such a large heat capacity that it takes a long time to equilibrate. Your equation assumes that equilibrium is reached instantaneously. Dana at 37 suggests that the transient climate response, which is what you are calculating, is about 2/3 the equilibrium response. Most people do not try to estimate climate sensitivity after all the ice has melted. The climate will be so different then that the error bars would be very large. The sea level would rise 70 meters!! That would cover the first 20 stories of the buildings in New York! At some point you have to say it is too far out to work on. The fact that there is even a small possibility of all the ice melting should get people concerned. Few people seem to care if all the great cities of the world are gone in 300 years. Good luck with your class, it sounds like a challenging crowd! -
L. Hamilton at 02:43 AM on 19 June 2012Scientific literacy and polarization on climate change
Eric, those polar questions were designed by other researchers back in 2005-6, for use on the 2006 and 2010 GSS. I've taken a different, very specific and present-oriented tack when designing new questions for 2011 and 2012 surveys. But in terms of the general conclusions, it appears that details of question wording matter less than one might think. -
dhogaza at 02:39 AM on 19 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
dana1981 - wording's better, thanks. -
Composer99 at 02:34 AM on 19 June 2012Glimmer of hope? A conservative tackles climate change.
ralbin: With regards to: So, what are the legal barriers and how would they be reduced? How would permitting be simplified? In the USA, this would mean reducing reducing local and state authority and de facto strengthening federal authority. Equally important, Adler's suggestion would likely involve reducing the ability of existing property owners to use court systems to obstruct wind developments. Again, this would tilt authority to administrative bureaucracies, most likely Federal level ones. This is hardly a libertarian, "conservative" approach. As far as I can see, from a logical perspective the "de facto strengthening" of federal authority does not follow from reducing local or state authority. In addition, you appear to be omitting the property rights of the wind farm developer in your statement about the property rights of nearby owners. Logically, reducing the ability of non-owners to override the developer's property rights (by interfering with a wind farm development) does not, of necessity, require additional bureaucracy or administration. -
dana1981 at 02:12 AM on 19 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
Lloyd @1 - I agree, the reason this myth persists is that certain individuals desperately want Hansen and co. to be "wrong", so once they arrive at that desired conclusion, their brains shut down and they don't investigate further to see what Hansen being "wrong" means (what it means is that fast feedback climate sensitivity is ~3°C, which is what Hansen currently argues). I still have yet to see a climate contrarian perform an intelligent and throrough analysis of Hansen's 1988 projections. Solheim, Michaels, Christy, etc. all stop when they reach the convenient "Hansen was wrong" conclusion. dhogaza @2 - fair point, I re-worded that sentence, although as Kevin notes, it's not quite as simple as just having better coverage. The point I was trying to get at is that Solheim should not be using HadCRUT3 when it has a known cool bias and has been replaced by HadCRUT4. There is absolutely no reason to continue using an outdated data set like HadCRUT3, unless of course the outdated data are convenient for the argument you're trying to make. -
Kevin C at 01:42 AM on 19 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
Except that HadCRUT4 didn't really address the coverage bias either. -
dhogaza at 01:33 AM on 19 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
"most likely from HadCRUT3, which due to its cool bias has of course been replaced by HadCRUT4..." This could be worded better ... it can be read as though HadCRUT4 was created for exaclty the reasons denialists claim adjustments are made to various temperature datasets, to make things seem worse than previous work indicated. HadCRUT4 was released because it has better coverage. Which just happens to remove the cool bias HadCRUT3 suffered from because of more limited coverage ... Anyway, call me paranoid but we don't want to toss the denialsphere things that can easily be quote-mined, right? -
Lloyd Flack at 01:23 AM on 19 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
This is an example of what happens when you try to win rather than understand. Rater than try to understand Hansen's calculations and then criticize based on that understanding Solheim has read Hansen maliciously, looking to find fault and missing context and reasoning. Hardly the only denialist that I have seen do that. In fact most of their rebuttals of climate science pieces suffer from this flaw, at least in my experience. -
curiousd at 00:20 AM on 19 June 2012Lessons from Past Predictions: Hansen 1981
Hi Sphaerica, Sure, all kinds of surprise effects might come about - like releasing methane from the Arctic....but my motivation here is just to find out: Is the temperature increase, including all effects long and short term, always given by concentration proportional to exponential of the increase? This academic question is of interest to me because my path to do my bit here runs through education and includes being able to explain this stuff accurately to people most of whom have PhDs in physics, but none of whom have much of a clue about climate science. They will think this exponential dependence of the concentration on temperature increase is really neato in a geek like way and quite unexpected, but will ask questions. The first question likely will be: if this relationship includes the effect of the ice albedo, then how can you continue to have the same exponential dependence, in principle, even after the ice is melted? I think the discussion you give in post 38 tells me that "No, the exponential relationship cannot be in principle constant over the very long term with unchanging climate sensitivity." Tom Curtis, Your post was extremely helpful. So in my post 38 all I did was to use the exponential dependence and apply it to the climate sensitivities calculated by Hansen, and then I found out that only if one includes the effects of the Aerosols in 1951 - 1960, as is proper to do and is what they did by their normalization of the baseline, then the predicted temperature increase is bang on what happened. But Dana, none of that 2.8 degrees in the 1981 paper was a long term effect. -
curiousd at 22:46 PM on 18 June 2012Lessons from Past Predictions: Hansen 1981
Hi, Dana and Michael and everyone else here, I am trying to pin this down, that's all. So I understand it. In the 1981 Hansen calculation he used a succession of models and his 2.8 climate sensitivity included (a) CO2 alone (1.2 degrees) (b) water vapor feedback by holding the relative humidity constant (1.9 degrees)(c) something called the moist adiabatic lapse rate - which I have no clue about yet (down to 1.4 degrees) , and "Clouds at fixed temperature levels so they move to higher altitudes as temp increases" (back up to 2.8%) so that 2.8 % does not contain any long term feedbacks!! Elsewhere on this site I have been told that indeed the 2.8 does not contain the long term ice - albedo feedback. The only calculations I am doing is taking the climate sensitivity for the various effects as calculated by Hansen, et all, and plugging into C2/C1 = 2 ^ (t/tsensitivity). What is wrong with that? -
Eric (skeptic) at 21:13 PM on 18 June 2012Scientific literacy and polarization on climate change
From the paper about the survey: "Hunting is more likely than climate change to make polar bears become extinct.” It's a trick question. Before polar bears could be hunted to extinction in the 1970's there was a treaty banning their being hunted from airplanes, etc. and they were not endangered by climate change at that time. Similarly, efforts to prevent their extinction from climate change would be similarly successful although with the criticism that it would result in a limited preserve and not a geographically wide and sustainable habitat. In general the survey is biased against respondents who believe in adaptation, e.g. "“Sea level may rise by more than 20 feet, flooding coastal areas.” By when? Hundreds of years from now? -
pvincell at 20:12 PM on 18 June 2012Scientific literacy and polarization on climate change
To elaborate, my experience thus far leading public discussions on climate literacy suggests that respect for differences will open the door to a populace that is more accepting of the scientific consensus on climate change. Most conservatives are people of good will, just like most liberals. I don't see how I can play a role in opening minds to the science of climate change if I am criticizing or demonizing people with ideologies that differ from mine. Furthermore, while I may not agree with the solutions my conservative friends propose, they have a right to bring to the table, those solutions that fit their values. -
redscourge at 18:31 PM on 18 June 2012Carbon Pricing Alarmists Disproven by the Reality of RGGI
I would not be such an opponent of the carbon trading schemes if [snipped accusations of dishonesty]Moderator Response: TC: Posting at Skeptical Science is a privilege, not a right. Please review the comments policy and ensure your posts comply so the privilege is not withdrawn. -
redscourge at 18:29 PM on 18 June 2012Carbon Pricing Alarmists Disproven by the Reality of RGGI
@funglestrumpet: This sort of thing is why the skeptics claim that they are being silenced; because people such as yourself are actively wishing for them to be silenced, and others who happen to be in higher places are [snip]! if they're wrong, they don't need to be silenced, just shown to be wrong.Moderator Response: TC: All caps snipped. Please review the comments policy and ensure your posts comply with it to avoid moderation. -
DSL at 13:16 PM on 18 June 2012Glimmer of hope? A conservative tackles climate change.
Gillian et al., I've had decent success when I avoid using absolutes (labeling, categorizing, using terminal rhetoric) and when I ask questions. The paid-for machine gains traction on the closed minds of those who want the silly memes to be true. Work on some of those minds publicly in comment streams and in face-to-face discussion. Open them up to the possibility not that AGW is real, our responsibility, and bad, but simply that it's possible that you can be reasonable, that someone who accepts the theory is not actually an ideologue or memebot. Model reasonable dialogue. Find common ground. Pop a few hypotheticals. Draw the person out from behind the curtain of ready-made opinion. Even spending a week working on one person in a public venue is worth it, because of the sharp contrast it provides to the Rush Limbaughs and Christopher Bookers of the world -- the opinion-makers. And, of course, modeling effective and respectful dialogue is a gift that keeps on giving. In the last few weeks, I've been able to move people from very loud and cliched claims of hoax to being open to talking about solutions to the problem. Of course, this has typically been something like, "Well even if you're right the carbon tax will be a total fail." It has taken a lot of time, but I'm pretty sure I'm not just working on one person at a time. It also confirms and informs the people who accept but don't understand the details. It's better than a "Shut up, you Repubnutter." -
sidd at 13:08 PM on 18 June 2012New research from last week 22/2012
Further, re Rignot, can we derive a figure for the amount of ice sliding into the ablation zone ? -
chuckbot at 11:58 AM on 18 June 2012Greenhouse gases are responsible for warming, not the sun
I think that fingerprinting is a powerful attribution tool, but occasionally I run into someone who claims that the GHG signatures (upper atmospheric cooling, night/day and winter/summer trends) are caused by increased humidity, which is ultimately caused by the sun. Of course, this is contradicted by observations of the solar activity, but I am curious if there are other problems with this hypothesis? One answer might be that model results don't show the same fingerprints from solar forcing, even though they do show the effects of increased humidity (eg, http://www.realclimate.org/index.php/archives/2007/12/tropical-troposphere-trends ). But then again such people tend to dismiss model results. Any other ideas?
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