Recent Comments

Prev  1818  1819  1820  1821  1822  1823  1824  1825  1826  1827  1828  1829  1830  1831  1832  1833  Next

Comments 91251 to 91300:

91251. Gilles at 06:30 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       DM : I'm just examining the formal logics of the argumentation , and I found loopholes in it. Of course it is easy to find cases where "everything wasn't held constant" : for instance just after a strong El Niño event, in 1999 or in 2011, temperatures were decreasing although forcings are supposed to increase steadily, precisely because "everything else" wasn't constant (major rearrangement in oceanic temperature distribution). So now you can argue that on a sufficient longer timescale, things are constant on average,but that's no more "pure logics" - you have to justify it technically - and they're technical issues, for instance the multidecadal PDO or AMO - so again you can argue that they aren't that important, but what about the explanation of the break of the temperature curve around 1940, etc, etc... and don't say that it is just for a "general audience", that is precisely the kind of issues that must be discussed carefully.
       Moderator Response: [Dikran Marsupial] Pointing out a theoretical loophole doesn't falsify the argument or the logic; for that you need to show that the loophole has actually ocurred, otherwise it is mere pedantry/rhetoric. As for the El-Nino event, I did mention the expected correllation is in the trend after excluding natural climate variability, so again you are demosntrating that you are not paying attention to the responses to your posts. There is a difference between careful explanation and pedantry; there is a good reason why the arguments are presented at SkS in different articles - so that each argument can be discussed carefully at an appropriate level of abstraction. They are discussed carefully, just not on this particular page, and quite rightly so.
91252. dana1981 at 06:27 AM on 24 March 2011
       Preventing Misinformation
       Cadbury #48:

       "Heidi Cullen at one point claimed that some flood was a 1 in a 1000 year event or something, I would hope we can all agree it was a preposterous claim."

       It's entirely common to label a particular weather event as 1 in 100 year, 1 in 500 year, etc. The 2010 Tennessee floods were 1 in 1,000 year event, for example. So unless you provide evidence that Cullen's statement was wrong, no, I don't agree it was a preposterous claim. Especially if she was referring to the floods in Tennessee, in which case not only would her statement not be preposterous, it would be entirely correct.
91253. Dr. Jay Cadbury, phd. at 06:26 AM on 24 March 2011
       Preventing Misinformation
       Well because its in a 3hr video and it would be hard to go through the whole thing to find the exact spot. I shall attempt though.
91254. Harry Seaward at 06:24 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       The 97% number stems from a 2008 master’s thesis by student Maggie Kendall Zimmerman at the University of Illinois, under the guidance of Peter Doran, an associate professor of Earth and Environmental Sciences. The two researchers obtained their results by conducting a survey of 10,257 Earth scientists. However, in the end, they chose to highlight the views of a subgroup of just 77 scientists, 75 of whom thought humans contributed to climate change. The ratio 75/77 produces the 97% figure that pundits now tout. The two researchers started by altogether excluding from their survey the thousands of scientists most likely to think that the Sun, or planetary movements, might have something to do with climate on Earth — out were the solar scientists, space scientists, cosmologists, physicists, astronomers and meteorologists. That left the 10,257 scientists in such disciplines as geology, geography, oceanography, engineering, paleontology and geochemistry who were somehow deemed more worthy of being included in the consensus. The two researchers also decided scientific accomplishment should not be a factor in who could answer — those surveyed were determined by their place of employment (an academic or a governmental institution). Neither was academic qualification a factor — about 1,000 of those surveyed did not have a PhD, some didn’t even have a master’s diploma. To encourage a high participation among these remaining disciplines, the two researchers decided on a quickie survey that would take less than two minutes to complete, and would be done online, saving the respondents the hassle of mailing a reply. Nevertheless, most didn’t consider the quickie survey worthy of response — just 3,146, or 30.7%, answered the two key questions on the survey: 1 When compared with pre-1800s levels, do you think that mean global temperatures have generally risen, fallen, or remained relatively constant? 2 Do you think human activity is a significant contributing factor in changing mean global temperatures? The questions posed to the Earth scientists were actually non-questions. From my discussions with literally hundreds of skeptical scientists over the past few years, I know of none who claims the planet hasn’t warmed since the 1700s, and almost none who think humans haven’t contributed in some way to the recent warming — quite apart from carbon dioxide emissions, few would doubt that the creation of cities and the clearing of forests for agricultural lands have affected the climate. When pressed for a figure, global warming skeptics might say humans are responsible for 10% or 15% of the warming; some skeptics place the upper bound of man’s contribution at 35%. The skeptics only deny that humans played a dominant role in Earth’s warming. Surprisingly, just 90% of the Earth scientists who responded to the first question believed that temperatures had risen — I would have expected a figure closer to 100%, since Earth was in the Little Ice Age in the centuries immediately preceding 1800. But perhaps some of the responders interpreted the question to include the past 1,000 years, when Earth was in the Medieval Warm Period, generally thought to be warmer than today. As for the second question, 82% of the Earth scientists replied that human activity had significantly contributed to the warming. Here the vagueness of the question comes into play. Since skeptics believe human activity has been a contributing factor, their answer would have turned on whether they consider a increase of 10% or 15% or 35% to be a significant contributing factor. Some would, some wouldn’t. In any case, the two researchers must have feared that an 82% figure would fall short of a convincing consensus — almost one in five wasn’t blaming humans for global warming — so they looked for a subset that would yield a higher percentage. They found it — almost — by excluding all the Earth scientists whose recently published peer-reviewed research wasn’t mostly in the field of climate change. This subset reduced the number of remaining scientists from over 3,000 to under 300. But the percentage that now resulted still fell short of the researchers’ ideal, because the subset included such disciplines as meteorology, which Doran considers ill-informed on the subject. “Most members of the public think meteorologists know climate, but most of them actually study very short-term phenomenon,” he explained, in justifying why he decided to exclude them, among others. The researchers thus decided to tout responses by those Earth scientists who not only published mainly on climate but also identified themselves as climate scientists. “They’re the ones who study and publish on climate science,” Doran explained. “So I guess the take-home message is, the more you know about the field of climate science, the more you’re likely to believe in global warming and humankind’s contribution to it.” Once all these cuts were made, 75 out of 77 scientists of unknown qualifications were left endorsing the global warming orthodoxy. The two researchers were then satisfied with the findings of her master’s thesis. Are you?
       Moderator Response: [muoncounter] It appears this piece is cribbed verbatim without any citation from denial blogs; a violation of Comments Policy here.
91255. CBDunkerson at 06:24 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       LJR #793: So now you are disavowing your own prior arguments? Or wasn't it you who wrote; #715: "Low temperature, (lower energy) atmosphere adding radiative heat to the warmer surface is a violation of the 2nd law." #758: "See this process (unlike the magic box) abides the 2nd law, Hot to Cold." #765: "So regardless of re-radiation and reflection, the atmosphere can NOT warm the warmer Earth...Period." You have said all these things. Right there in the thread history. Yet now you deny it to avoid answering my challenge; "LJ Ryan, I note that you continue to make nonsense claims about greenhouse gases being unable to redirect energy from a colder area to a warmer one while refusing to answer how a parabolic mirror does so." How does the observed reality that EM radiation travels from the surface of a parabolic mirror to the hotter object at the mirror's focal point not disprove your various statements quoted above?
91256. Dr. Jay Cadbury, phd. at 06:20 AM on 24 March 2011
       Preventing Misinformation
       There was a hearing several months ago in congress, the first group consisted of Lindzen, Cicerone, Cullen and several others I cannot recall. Heidi Cullen at one point claimed that some flood was a 1 in a 1000 year event or something, I would hope we can all agree it was a preposterous claim. She also gave the highest IPCC estimate for warming that they predict, which I thought was misleading.
       Moderator Response: [Dikran Marsupial] There is nothing preposterous about the claim at all per se; there is a well established field of statistics called "extreme value theory" that is the basis for statements of exactly that form. There is an excellent book on the subject by Stuart Coles, see page 49 in particular, the one in 1000 year figure is what is known as the "return period".
91257. Dr. Jay Cadbury, phd. at 06:14 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       In the meantime, I asked him about co2 saturation and here is what he had to say. As for CO2 saturation, yes, it is saturated in the sense the warming due to more CO2 is proportional to the logarithm of the CO2 concentration, not to the concentration itself. I am attaching some graphics to illustrate this "saturation." You will have to know a fair amout of physics to follow the remaining discussion. The first slide shows the "logarithmic" response of temperature to increasing CO2 levels. As you know, log (0) = - infinity, so what is meant by logarithmic is that the response function fits a logarithm pretty well for CO2 concentrations above 100 ppm or so. The reason for the "logarithmic" response is shown in the subsequent slides, the first of which has some blackbody curves superimposed on the MODTRAN model spectrum. For CO2 concentrations above a few 100 ppm the CO2 absorption band at 666 cm^{-1} (about 16 microns) is nearly "saturated," and the earth emits at about the ~ 220 K temperature of the tropopause over most of the band. More or less CO2 makes almost no difference in the central part of the band, as you can see from the figures. The exceptions are: 1) the sides of the band, where the CO2 emission is from altitudes below the tropopause, where the atmosphere is warmer and therefore a better emitter of radiation; 2) from the extremely narrow spike in the center of the band. This is the intense "Q branch" (as opposed to the much broader "P and R branches" that make up most of the band. The very strong Q branch is radiating from altitudes in the stratosphere, where it is warmer than the tropopause. The radiation efficiency from the sides of the bands does diminish as you add more CO2. Almost all of the direct greenhouse warming due to increasing CO2 comes from line broadening. You can see from the figures that it is not a very big effect. Qualitatively, satellite measurements of the earth's spectra look almost exactly like the MODTRAN model calculations attached here. The details are different for different locations, for example, the Sahara desert, or the tropical Pacific Ocean. And the calculations are for clear air. The picture changes dramatically when there are clouds -- which is another story. The bottom line is that the logarithmic response (other things being equal) is very solid physics if you ignore any changes in cloud cover or water vapor. From what data I have seen, it seems that clouds and water vapor do not cause much amplification and may in fact attenuate the direct warming from added CO2.
       Moderator Response: [muoncounter] See the existing thread on CO2 saturation. Try to put comments on the appropriate thread; use Search. [not muon] Or peruse the List of Skeptic Arguments
91258. Dr. Jay Cadbury, phd. at 06:12 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       @Rob Do you much about the Bern model? Is it important to the IPCC assessment?
91259. Dr. Jay Cadbury, phd. at 06:10 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       @Rob I asked Dr. Happer about the surface station versus satellite record and will post the response once I have it.
       Moderator Response: Not on this thread, because I will promptly delete your comment. Post it on the correct thread I pointed you to.
91260. Philippe Chantreau at 05:53 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       To moderator: OK, the trolling has indeed gone on long enough. Sorry for adding to it.
91261. DSL at 05:51 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Me: "In other words, why doesn't the solar cooker cool to near absolute zero when pointed at the open night sky?" LJ Ryan: It fact, it's temp. drops well below ambient. However the atmosphere, as you know, is not absolute zero. Thus potential drop is limited by atmos. temp. and the rate of drop is determined by delta T between cooker contents and the sky. If the atmosphere is same temp as the cooker no cooling occurs. If the atmosphere is warmer then the cooker, the contents warm. Or, rather, if the cooker is radiating energy at the same rate that the atmosphere is radiating at it (removing conducted energy from the equation), then the cooker will remain at the same temperature. If the atmosphere is not adding radiated energy to the cooker, the cooker--if unable to shed via conduction (e.g., in a vacuum box)--will cool to near absolute zero when pointed at the night sky. But, of course, all atmospheric layers do radiate, and some of this radiation is absorbed by warmer surfaces and warmer atmospheric layers. Here's the key, though: the current temperature of any atmospheric layer or material within the system is that specific temperature because the atmosphere is already adding its radiated energy. The system is dynamic. if we take away the atmosphere, the surface eventually (quickly) reaches a lower equilibrium temperature. That the atmosphere doesn't heat the surface or warmer atmospheric layers is false. The heating is already taking place, and the result is the equilibrium temp. It's a mistake to think that this equilibrium temp is a baseline temp to which atmospheric energy is added. If we increase the radiative density of the atmosphere, the radiation has a greater chance of being redirected (in all directions). The maze is more complex, the pachinko machine has more pins, the dam is higher, etc. etc. The amount of available, usable energy in the lower layers increases because it's around longer in those layers. Do I have this right?
91262. muoncounter at 05:50 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       LJR: "neither he nor I believe earth is a blackbody." Now that's a radical change of heart, as you specifically described earth's blackbody temperature here. And you've totally ignored the complete defenestration of your argument by KR (#773-775) and CBD (#785). As far as 'fundamental flaws' (#797), you haven't proven them; a reference to someone else's blog and 'google solar cooker' do not cut it as scientific source material.
91263. Gilles at 05:39 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       Well DB actually you seem to have charged yourself with a burden : convince skeptical people that you're right. For if your only goal is to convince those who are already convinced, all the work you're doing is not very worthwhile. So you seem to have chosen some way of convincing people : sticking on scientific facts and argue scientifically. I'm curious to know if you have good arguments to be convincing. So far, what I've seen is only reassessed things that everybody who is interested in this issues has already seen thousands of time. I try to present the issues I see with your arguments. Now if your answer is "you're not a good guy, you haven't made your homework", well, technically, you have missed your goal. For if you think that the goal is to convince a vast majority of people of giving up all FF, to avoid a catastrophe for the whole mankind, (obviously not an easy one), it's not a good idea to insult these people who make some efforts to come here - but try to present their own argument and explain why they don't believe a priori in everything you're saying. That's not "my" choice, that's "your" burden. So let's make some comments on the "logics" presented in your thread "1. Increasing the level of a greenhouse gas in a planet’s atmosphere, all else being equal, will raise that planet’s surface temperature." True " 2. CO2 is a greenhouse gas." True "3. CO2 is rising." True " 4. Therefore (given 1-3 above) the Earth should be warming." Wrong - you forgot "all else being equal". It just disappeared. Nothing insures that "all else " stay equal " 5. From multiple converging lines of evidence, we know the Earth is warming." time scale missing, but ok, let's assume it's at decadal time scale "6. The warming is moving in close correlation with the carbon dioxide." wrong. It has some correlation, but not very close - CO2 is exponentially rising whereas temperature has a much funnier behaviour. " 7. The new CO2 (as shown by its isotopic signature) is mainly from burning fossil fuels." Probably true. " 8. Therefore the global warming currently occurring is anthropogenic (caused by mankind)." Obviously simplistic - which part ? how much? who said that "everything else was equal"? so rather poor logics -not a very good teacher in my sense.
       Moderator Response:

       [Dikran Marsupial] Stating that all things not being equal does not make it true. If you want to show that point was wrong, you need to specify what conditions are not equal and why they invalidate the hypothesis. Also while CO2 is rising exponentially, the forcing is logarithmic in CO2, and hence the expected warming trend is linear (once internal climate variability is considered). That is the expected correllation and it is pretty much what is observed, so that point is at best pedantry over the exact meaning of "correlation". Lastly, of course it is simplistic, this is a blog for discussion of the science for the general public, of course it is going to be simplistic. Also being simplistic doesn't make it wrong. For a less simplistic explanation, quantification, see the IPCC WG1 scientific basis report. DBs logic is fine.

       [DB] In case anyone's curious about the correlation of warming and carbon dioxide, r = 0.874 for ln CO2 and dT 1880-2008.

91264. e at 05:37 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       LJ, Please clarify your statements where you say "Adding more radiation of the same magnitude does NOT change output". What precisely do you mean by "more" radiation of the same "magnitude"? By magnitude are you referring to the frequency of the radiation? Let's say we have an object in a vacuum absorbing one photon per second with a wavelength of 1um for all photons. If we increase the rate of incident energy to two photons per second, but they all remain at a wavelength of 1um, are you saying the amount of radiation emitted by the object does not change?
91265. Philippe Chantreau at 05:37 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       You can't formulate anything in a coherent fashion. You're the one evading my question with irrelevant gibberish. I am not talking about adding radiation of any magnitude, whatever that means. I am talking about a spherical blackbody receiving solar radiation at a constant rate in w/sq m, in the solar spectrum. If, by any means, that blackbody's ability to radiate energy out is impaired, what will happen to its temperature? About this: "it's temp. drops well below ambient" How does it square with this? "If the atmosphere is same temp as the cooker no cooling occurs." It drops below "ambient" but then if the temp is the same as the ambient atmosphere, no cooling occurs? More incoherence and more nonsense.
       Moderator Response: Let's end the sniping here, there is nothing constructive coming from it.
91266. NewYorkJ at 05:31 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       "The answer is, 97 out of 100 agree that the climate is changing and that we are causing it. From my own experience, such a high proportion is quite unusual. As scientists we are trained to be professional sceptics, who doubt everything and who moreover love a good debate. Therefore putting 3 scientists together in a room sometimes results in an argument with 5 different opinions." Actually, the reason I think it's unusual is that it's an issue that has political/economic implications, and such issues tend to bring out a lot of industry shills, ideologues, and contrarians seeking fame.
91267. L.J. Ryan at 05:28 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       DB "You have yet to demonstrate the physical-ness of your position, as other participants have pointed out to you several times." Physical-ness of MY argument. Yet you proponents contradict one another when TRYING to explain the lack of "physical-ness" of my contentions. You press for answer on behalf of whom you agree. Yet chastise skeptics for re-posting question which remain unanswered.
91268. L.J. Ryan at 05:24 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       KR 773-775 A bit sleight of hand KR. Power input is also based on emissivity. Lower emissivity, higher reflectivity, thus less power input. Lower "fixed" input lower base temp i.e. lower then 255K. So GHG effect must account for more then 33K. Said differently, a body does not absorb one emissivity and radiate at another. Regarding the Alan Siddon post, neither he nor I believe earth is a blackbody. The gist of the post, blackbody represent max radiation input and max output. Regardless of reflection and re-radiation, max radiation output cannot be exceeded less higher energy input. Very simple concept, proven by years of actual data measurements. Do you agree?
91269. CBDunkerson at 05:22 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       It'd be nice if there were a 'persistent thread' or somesuch where people could ask questions/make claims. As it is they get scattered all over and the moderators are always playing 'whack-a-mole' trying to get things onto the proper thread. Jay Cadbury, the radiative forcing value of atmospheric CO2 will change as the concentration does. Since the concentration is increasing I don't see how the IPCC estimates can be decreasing... unless you are looking at forcings against different baseline values or somesuch. That said, I recall that Michael Crichton used to make a similar claim about the estimated temperature change from a doubling of CO2 decreasing... but he did so by falsely citing the highest value in the range of estimates as the only estimate. If you instead took the lowest value then the IPCC estimate increased each time... basically, the uncertainty range got smaller with each report as additional studies were performed. The most likely value has remained about 3C for a doubling of CO2 in all of the IPCC reports.
91270. L.J. Ryan at 05:21 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Philippe Chantreau 772 "Considering that the body in question is continuously receiving energy at a more or less constant rate, it does not seem so difficult to imagine that its temperature will increase if the rate at which it can radiate that energy is decreased. In fact, I would have a hard time to understand if it did not warm up under these conditions. " Philippe, blackbody radiation is based upon a "constant rate". Adding more radiation of less magnitude does NOT change the output. Adding more radiation of the same magnitude does NOT change output. Adding more radiation of higher magnitude DOES change the output. Do you agree? Any interested readers should note your evasion, and that you do not feel confident enough to discuss the case on its merits.
91271. L.J. Ryan at 05:18 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       CBDunkerson 785 "LJ Ryan, I note that you continue to make nonsense claims about greenhouse gases being unable to redirect energy from a colder area to a warmer one while refusing to answer how a parabolic mirror does so." Where/when did I say this?
91272. Philippe Chantreau at 05:17 AM on 24 March 2011
       Arctic sea ice has recovered
       Looking again at NSIDC today, it seems indeed the max extent was reached some days ago. If it remains there, that is quite low. However, there is till a possibility of a very unusual weather event that would cause an uptick, so a couple more weeks are necessary for absolute certitude on the max extent (note the shape of the standard deviation shaded area going into spring). Interestingly, Antarctic sea ice has been below average and is quite sluggish to pick up growth. The global sea ice area is very far below baseline.
91273. L.J. Ryan at 05:16 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       DSL 760 "The reflective surface focuses incoming radiation." --yes, solar radiation when cooking. "That radiation could be coming from the atmosphere." ---from the sun for cooking...that is how it works. If you point away from the sun the target COOLS below ambient temperature. "Your argument is that we can't differentiate between radiative transfer and conduction/convective transfer." ---I'm not sure what you mean. "In other words, why doesn't the solar cooker cool to near absolute zero when pointed at the open night sky?" ---It fact, it's temp. drops well below ambient. However the atmosphere, as you know, is not absolute zero. Thus potential drop is limited by atmos. temp. and the rate of drop is determined by delta T between cooker contents and the sky. If the atmosphere is same temp as the cooker no cooling occurs. If the atmosphere is warmer then the cooker, the contents warm.
91274. Rob Honeycutt at 05:13 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       Jay... Lindzen's record so far is not so stellar. Skeptics hold him up as an example but his arguments are not so strong as they like to believe. He's focusing on the right area, uncertainties in climate sensitivity mostly related to cloud effects, but he's not been able to establish the numbers he's presented in a substantive and meaningful way. Lindzen says surface station records are unreliable but we now have satellite data that almost perfectly corroborates the surface station data. And as for the IPCC changing radiative forcing down three times... I'm not finding that to be accurate. Here is a the diagram from the TAR. And here is the same diagram from the AR4. You will note that actually the radiative forcing of CO2 went up in AR4. You should also note that this is an area of research that has a "high" level of understanding.
91275. NewYorkJ at 05:09 AM on 24 March 2011
       Of Satellites and Air – A Primer on Tropospheric temperature measurement by Satellite
       It would be nice if the other analysis, such as V&G, provided up-to-date monthly data, such that sites like woodfortrees could easily include it. All we seem to get in the blogosphere are Spencer's blog updates, where trend analysis changes to frame any recent data as a cooling trend.
91276. Dr. Jay Cadbury, phd. at 04:40 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       Well the problem here is that the data is in question. And I know people are going to argue about this but Richard Lindzen himself has said the surface station records are questionable. Furthermore, the IPCC has changed the radiative forcing value of co2, 3 times, with all adjustments being lowered.
       Moderator Response: See the Argument "Temp record is unreliable," and put further comments about surface station records' quality there, not here.
91277. CBDunkerson at 04:36 AM on 24 March 2011
       CO2 has been higher in the past
       What topic are you talking about only 32 years of data for? That would seem to be the satellite record only, but CO2, Arctic warming, and all other topics I might guess you were referring to have records going back further than that. As to your question about Happer... note that you assume Gore did fire Happer. Which is Happer's story. No 'skepticism'? Just accepting it as fact? Consider that while Happer now claims he was fired because he disagreed with Gore on global warming... back at the time his claim was that he was fired because he disagreed with Gore staffers on the ozone hole. Why would expect people at realclimate (or here) to know whether either of Happer's claims were true or why he was actually fired? That said, please do note that Happer was one of those who claimed that ozone depletion wasn't happening, that it wouldn't have harmful effects if it were, and that legislation being pushed to address it would bankrupt the economy. The scientific community overwhelmingly said otherwise even at the time. Now history has conclusively showed that it was nonsense. Fast forward 20 years and we find Happer singing the same song about global warming... right down to the claim that he was 'fired over the issue'.
       Moderator Response: [Dikran Marsupial] Please, no more discussion of the reason for Happers firing, it is off-topic. Further discussion will be deleted.
91278. les at 04:25 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       38 Gilles - my links refer to past pists I never claimed my links provide scientific evidence of any thing if you think they should have, that kind of ironed my point about your [lack of] grasp if what science is.
91279. johnd at 04:12 AM on 24 March 2011
       CO2 has been higher in the past
       Regarding the moderators comment "Snipping is done as a courtesy to the commenter, to help them understand exactly what violates the comments policy." at Dr. Jay Cadbury, phd. at 01:21 AM. I think snipping is perhaps an even greater courtesy to all other readers as it provides a transparency that is otherwise missing and allows all to develop a better sense of the flow of the argument. Above all else, I believe it is transparency that determines how much faith readers will have in the moderation process, and snipping brings such transparency that I would like to see it become standard practice.
       Moderator Response: It takes more time, though. And patience. We all are volunteers here.
91280. Dr. Jay Cadbury, phd. at 04:07 AM on 24 March 2011
       CO2 has been higher in the past
       Well this is a topic where 32 years of data just doesn't do it for me. @Rob Let me give you another example of a comment realclimate won't touch. I have often asked them why Al Gore fired Dr. Happer and they will not comment on it.
       Moderator Response: [Dikran Marsupial] Probably because contravenes the comments policy at RealClimate, just as it contravenes the comments policy here. Politics is off-topic here, this is a forum for discussion of the science. Likewise accusations of dishonesty or deceptions or ad-hominems are not acceptable, which is where the discussions seems likely to be headed. So no further please.
91281. CBDunkerson at 03:20 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       So far as I know, even the few 'skeptic scientists' (e.g. Lindzen, Spencer, et cetera) "agree on all the main facts of AGW". At this point the only thing remotely cluefull people question is how much AGW there will be... and even there 'less than 2C for a doubling of CO2' is the belief of a vanishingly small minority.
91282. ranyl at 03:16 AM on 24 March 2011
       Pre-1940 Warming Causes and Logic
       Interesting if complex discussion. It strikes me that looking at the NH (not global) reconstructions being posted, that there is a clear..ish 1000year cycle going on, with the peak of the lastest warm period at about 1900-1980, this is unlikely to be due to the changes in the sun's intensity as this it appears from the above this might have very little affect unless significantly amplified by another factor for which there is little to no definitive evidence. That leaves us ocean current changes for the warming from 1900-1940, plus the other factors listed in the blog post (human, low volcanoes, a little sun etc) which all tend to exaggerate the effect. After 1940's matters become complex as sulphur emissions rapidly rise to cause a cooling particularly in the NH, so natural variation is now altered by increasing CO2 and sulphur emissions, balancing each other to a degree and producing a period of limited variance and a mild cooling trend as would be in keeping with the 1000yr cycle. Also of course there is the longer cycle of precession causing a longer term cooling to the NH. So it seems that natural warming to MWP levels in the NH should have been expected for the 1800-190o. The worrying aspects are that the CO2 additions bit likley add some to pre-1940 warming, however since then for 30-40years, therefore until 1980 CO2 warming was masked by SO2 cooling, which means that the recent warming after 1980 is primarily the earth coming into equilibrium with with the CO2 rise until then, i.e. ~335ppm, we added another 60ppm in 30 years, and all that heating is about to realised, and keep in mind a significant amount of that warming is being masked by SO2 from India and CHina still. No wonder the CS from the past is so much higher, they didn't have any coal powered stations to mask it with SO2 for such a long period of time. CS is a difficult beast and has to be totally dependent on initial conditions (why CS to CO2 can be masked with a radiative blocker in the air, or reduced if there is less ice to melt!) and also prone to hystersis type changes as ice burdens rise and fall, snowball to greenhouse and full glacial to inter-glacial, from inter-glacial 100,000yr to inter-glacial 41,000yr, to NH ice free, to whole globe ice free. There is no way CS to a release of CO2 is the same during all these periods and why values for it vary from 1.5-12C or more. Where is CS now? Not sure but at present there potential of a large and rapid albedo accelerant the Arctic ocean, and warming this will not only affect the arctic it will influence weather patterns and ocean currents world wide. There is also the permafrost and the Greenland and WAIS ice sheets to consider meaning CS at present has a large very sudden albedo change potential and several large geologiclaly fast albedo changes to come, meaning CS under these initial conditions is very unlikely to be low, indeed if Pliocene records are right, then an equilibrium CS of 7.5-12-5C is very likely which 4.5C per 100years doubling is the lower limit of CS not the highest. So the warming episode of 1900-1940 seems natural yet amplified by CO2 to a small degree, then CO2 effects are masked until mid-1980's and then its take off to a new climatic paradigm for the earth, the choice that needs to be made is how to prevent that climatic shift coming from being too large for even informed planned adaptations to be effective?
91283. muoncounter at 03:10 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       #30: "I would much preferred ... 51% of scientists to agree on all the main facts of AGW." Why do I suspect that if you got your preference, you'd be declaring AGW null and void because 'only' 51% agree?
91284. Gilles at 03:08 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       grrr .. do not contain
91285. Gilles at 03:07 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       DB, les : sorry but your comments do not content any scientific evidence that you're right- actually you're just claiming that you're right, or referring to other threads where you're claiming that you're right. I agree that absolute certainty does not exist, strictly speaking - however it exists "For all practical purposes". As an example, I am ready to accept ANY bet (even at 1 to 1000000) that the sun will rise tomorrow. So we could define a certainty "FAPP" by accepting any bet at any odd- after all, one dollar is one dollar. Personally, I am ready to bet at any odd on the validity of the gravitation law up to some (computable) accuracy, that no biological species will suddenly appear from nothing, or that nothing will disprove the fact that the Universe is more than 10 billion years old. I am not ready to bet at any odd on predictions based on the fact that the global warming since 1900 is mainly anthropogenic. Are you ? if yes, I'm interested in a bet with you at a very interesting rate ... for me :).
       Moderator Response:

       [DB] The linked post I gave you contained a parable; one based on a National Academy of Science statement (a reference which should have answered much of your questions about scientific consensus and warming attribution). Ironic, you being a teacher failed to note that. As a teacher then, you were given homework to do (you blew off the reading assignment). Your grade is based on you doing the work assigned to you; that is incumbent on the student, is it not?

       "Feed a man a fish and he'll be fed...for a day

       Teach a man to fish and he'll never be hungry again."

       So either contribute to your own edification on this by doing the homework given you or cease wasting the valuable time of those well-meaning people who are trying to help you.

       Your choice.

91286. Kevin C at 02:52 AM on 24 March 2011
       Of Satellites and Air – A Primer on Tropospheric temperature measurement by Satellite
       That's an interesting review, thanks. It's also exactly what I want from an advanced article - a review of the literature and development of the field giving me a clear picture of what is known, what uncertainties still remain, and what are the major contributions to the field. Well done!
91287. pbjamm at 02:27 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       The first paragraph indicates to me that the 97% figure was reached by analyzing "current literature" in the climate sciences, not by means of a cleverly crafted survey as claimed by rhjames. I have not had time to listen to the complete audio so I do not know if the source is made more clear there.
91288. Rob Honeycutt at 02:23 AM on 24 March 2011
       CO2 has been higher in the past
       Jay Cadbury... To put the bigger picture in context, RealClimate is a group of scientists who are real working climate scientists. They are discussing real climate science. They frequently delete posts that are long debunked or blatantly wrong. They have to in order to have a reasonable high level discussion. Personally, I don't post much there. I mostly just read and learn. Skeptical Science is established to specifically look at "skeptic" claims and address them by looking at the published literature. If you ask an easily debunked question at RC it will, appropriately, get deleted. If you ask the same question here we address it. You just need to watch the inflammatory language that is allowed at many other climate related sites. It's not allowed here from either side of the issue. (My posts get deleted as well when I get all worked up on a topic.)
91289. dana1981 at 02:12 AM on 24 March 2011
       Pre-1940 Warming Causes and Logic
       Sorry Gilles, you can't deny physics. The CO2 warming during the period in question is in the 0.1 to 0.15°C range. The ocean lag is only so large - to claim that only 33% of the equilibrium warming is realized over the period in question is not physically plausible.
91290. dana1981 at 02:06 AM on 24 March 2011
       Preventing Misinformation
       JulianRGP #42 - thanks, and good point. I revised the text accordingly.
91291. IanC at 01:54 AM on 24 March 2011
       Preventing Misinformation
       Arkadiusz, If I am understanding you correctly, your scenario is: 2ppm natural imbalance, 8ppm anthropogenic CO2 7.5ppm additional biosphere sink Your conclusion is that the net 2.5ppm increase is due to 2ppm natural imbalance and 0.5 anthropogenic CO2 which is impossible unless the sink differentiates the source of CO2. It should be 2ppm due to anthropogenic and 0.5 due to natural imbalance. Your scenario also misses a key piece of information. We know that only 50% of the CO2 we generate is going into the atmosphere, so the net natural sink (bio sink - imbalance) equals 4ppm in your scenario. The rest of the papers you cited stress that there are potential for amplification of the effects of anthropogenic CO2, and I am not sure how they help your point.
91292. CBDunkerson at 01:54 AM on 24 March 2011
       CO2 has been higher in the past
       Jay Cadbury, see info on Arctic amplification. About the only things I can think of which you might have heard of 'growing' in the Arctic (as supposed contradictions to global warming) would be claims that Arctic sea ice is 'recovering' because the extent does not hit a new record minimum each year (which is simply false since the trend lines are sharply negative) or that ice mass in central Greenland is increasing due to increasing precipitation, which is true but vastly offset by the decreasing ice mass along the coasts due to melt and export.
91293. Arkadiusz Semczyszak at 01:54 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       Worth seeing what he writes about Wikipedia: “A 2010 paper in the Proceedings of the National Academy of Sciences analysed "1,372 climate researchers and their publication and citation data to show that (i) 97–98% of the climate researchers most actively publishing in the field support the tenets of ACC outlined by the Intergovernmental Panel on Climate Change, and (ii) the relative climate expertise and scientific prominence of the researchers unconvinced of ACC are substantially below that of the convinced researchers". Judith Curry has said "This is a completely unconvincing analysis," whereas Naomi Oreskes said that the paper shows that "the vast majority of working [climate] research scientists are in agreement [on climate change]... Those who don't agree, are, unfortunately—and this is hard to say without sounding elitist—mostly either not actually climate researchers or not very productive researchers." Jim Prall, one of the coauthors of the study, acknowledged "it would be helpful to have lukewarm [as] a third category." In addition, you can visit this site to see here all magnitude the controversy about AGW. Historian and theorist of the scientific process and professor Weiner described as "the sequence of events" the creation and "life" of a scientific theory: a hypothesis - the research process = theory - the process of falsification = consensus - the process of falsification = 9?% - the negation of the theory - its "death"; only a few (?) percent = constants doctrine scientific. Skeptics are therefore needed, even in the case of consensus. A list of (achievements, name) - is still imposing. To this list I would add the Polish climate scientists - professors - about the great experience of science. The authors more famous research in my country, I mention: Marsz, Trepińska, Boryczka, Ustrnul ...
91294. les at 01:53 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       Good grief ... don't people get tired in going round in circles? We did "settled science" here Settled facts, in real world science, are always established against a background of uncertainties... anyone who has ever done science knows that. And, 34 Gilles "I'm sorry, but I have no reason to believe you're more qualified than me to judge what a real scientific attitude is." Given the support of your hypothesis here, you can't really claiming to have shown any real scientific prowess now, could you.
91295. Gilles at 01:41 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       DB : I'm sorry, but I have no reason to believe you're more qualified than me to judge what a real scientific attitude is. Example drawn from your link : "Teacher : Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities." "Settled facts" and "very likely" is obviously contradictory : "settled facts" means absolute certainty - there is absolutely no doubt that the origin of solar energy is thermonuclear fusion, for instance, for we don't have any plausible other explanation. on the other hand , "much of this warming is very likely due to human activities." is not a "settled fact" - actually it is not even a "fact" ! which "warming" are we talking about ? if we consider the 10000 last years, it is certain that much of the warming is not due to human activities.
       Moderator Response: [Dikran Marsupial] I have already pointed out to you today that you are not reading the replies to your posts very well. I have also pointed out that there can be no absolute certainty regarding causal relationships in the real world. The fact that you have just ignored the second point reinforces the truth of the first. It is ridiculous pedantry to assume that "the science is settled" means there is absolute certainty; most are able to use their common sense to reconcile the two statements as meaning something along the lines of "the evidence is very strongly in favour of the generally accepted theory". The "regarded as" implies that the theory is only treated as if it were an established fact, not that it actually is one, i.e. a very safe assumption. As I said, please read comment more carefully and try and find the truth in them rather than (what you incorrectly consider to be) the inconsistencies.
91296. Dr. Jay Cadbury, phd. at 01:21 AM on 24 March 2011
       CO2 has been higher in the past
       Well I have to say I am shocked. The reason I am shocked is because these are pretty good answers and I couldn't get them on realclimate or ( -snip- ). This website sets a great example and I think above mentioned sites could take a lesson. @IanC What do you mean when you say "the artic is warming at twice the rate of the GAT"? I've been under the impression that parts of the arctic are warming but there are also parts growing?
       Moderator Response: [DB] Inflammatory portion deleted.
       
       [Not DB] Normally we don't snip out offending portions of comments; we just delete the entire comments. Snipping is done as a courtesy to the commenter, to help them understand exactly what violates the comments policy. DB is being more forgiving than I am, given the aggressive and insulting language in your first several comments here.
91297. CBDunkerson at 01:12 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Damorbel: "Doesn't the energy come from the Sun and is just redirected by the mirror?" Irrelevant gibber-gabber. The source of the radiation does not change its behavior, but even if it did... the energy being redirected by the greenhouse gases 'came from the Sun' too. The object at the focal point of the parabolic mirror is warmer than the air around it, which is in turn warmer than the mirror. Yet energy moves through space from the cold mirror to the warmer air to the warmer still object. This is exactly what you claim violates the 2nd (and/or 1st) law of thermodynamics when greenhouse gases do it. So how is this commonly observed phenomena possible? It violates what you claim to be a fundamental law of physics, but it is observed reality. Ergo... your claims about thermodynamic laws must be false.
91298. DSL at 00:52 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Damorbel: "No, I didn't say that. The photons emitted downwards have lower energy than those at the surface so there is no warming of the surface, it is the emitting gases in the upper atmosphere that are warmed by by the (more energetic) photons emitted by the surface." So the natural question, then, is "what happens to these lower-energy photons?" Are they or are they not absorbed by the surface? If not, what happens to them?
91299. damorbel at 00:48 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #787 DSL you wrote:- "you're saying that the photons emitted by the atmosphere are only emitted away from the surface. " No, I didn't say that. The photons emitted downwards have lower energy than those at the surface so there is no warming of the surface, it is the emitting gases in the upper atmosphere that are warmed by by the (more energetic) photons emitted by the surface. And further you wrote:- "No photon could possibly be emitted toward the surface, because the surface is warmer. Do you agree?" No I don't agree. See the first answer.
91300. damorbel at 00:40 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #785 DB you wrote:- "This proves that energy can flow from warmer areas to cooler ones... " The basic 2nd Law. Further you wrote:- "just as using the cooker/parabolic mirror during the day proves that energy can also flow from cooler areas (the mirrored surface) to warmer areas (the heated object at the focal point)." When a mirror focusses the Suns image on the food you are saying... that the energy comes from the ....mirror? Ahem, CBD I think this is not right. Doesn't the energy come from the Sun and is just redirected by the mirror? A mirror is about as far from a black body as it is possible to get, it doesn't absorb radiation. A mirror's temperature is not changed by incident radiation because it is reflected without being absorbed; that is why a mirror is used to block radiation to and from a vacuum flask. Likewise mirrors do not emit radiation; you claim that heat (in a solar cooker) 'goes from the mirror' but the temperature of a mirror is not changed when the sun shines on it, only the food is cooked!

Prev  1818  1819  1820  1821  1822  1823  1824  1825  1826  1827  1828  1829  1830  1831  1832  1833  Next