Recent Comments

Prev  1824  1825  1826  1827  1828  1829  1830  1831  1832  1833  1834  1835  1836  1837  1838  1839  Next

Comments 91551 to 91600:

91551. 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.
91552. 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.
91553. 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.
91554. 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.
91555. 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.
91556. 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?
91557. 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?
91558. Gilles at 03:08 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       grrr .. do not contain
91559. 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.

91560. 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!
91561. 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.
91562. 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.)
91563. 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.
91564. dana1981 at 02:06 AM on 24 March 2011
       Preventing Misinformation
       JulianRGP #42 - thanks, and good point. I revised the text accordingly.
91565. 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.
91566. 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.
91567. 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 ...
91568. 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.
91569. 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.
91570. 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.
91571. 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.
91572. 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?
91573. 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.
91574. 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!
91575. Arkadiusz Semczyszak at 00:34 AM on 24 March 2011
       Preventing Misinformation
       ... and on Commentary on the RealClimate from 2004 shows how currently is growing rapidly science.
       Moderator Response: [DB] I'm sorry, Arkadiusz, I don't understand this one. Is this an extension of your previous comment? It is incomplete as it stands now.
91576. DSL at 00:27 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Damorbel: "Since the atmosphere is colder than the surface any radiation from it will not warm the surface because its photons do not have the energy to do this. What does happen is, photons from the surface, having more energy than photons in the upper atmosphere warm it, the heat thus transferred upwards is re-radiated (by GHGs) into deep space, keeping them cool. Do you agree?" So you're saying that the photons emitted by the atmosphere are only emitted away from the surface. No photon could possibly be emitted toward the surface, because the surface is warmer. Do you agree?
91577. Gilles at 00:27 AM on 24 March 2011
       Why we have a scientific consensus on climate change
       DB : I am not rejecting the answers. I am rejecting the claim that we have definitive answers, and that no doubt is now allowed. That's not a "rhetoric" point of view. That's a point of view, and for me it is scientifically based, because science is exactly that : examining pieces of evidence and keep researching as long as they aren't clear.
       Moderator Response:

       [DB] Then it is clear you simply do not understand how science works nor the meaning of scientific consensus. This would be a step towards greater understanding in both matters. I suggest reading it.

91578. Tom Curtis at 00:19 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Damorbel @780, One last chance:

       Most GHE explanations say that this 'slowing' is because of a warming effect on the surface by radiation from GH gases in the atmosphere. Since the atmosphere is colder than the surface any radiation from it will not warm the surface because its photons do not have the energy to do this. What does happen is, photons from the surface, having more energy than photons in the upper atmosphere warm it, the heat thus transferred upwards is re-radiated (by GHGs) into deep space, keeping them cool. Do you agree?

       1) The Green House Gases in the atmosphere undoubtedly radiate in all directions as, a) this is the predicted behaviour in theory of radiation; and b) the radiation from those gases have been observed from space, and from high flying planes lookding down; and from the ground and from low flying planes looking up. An example of one such measurement is found in the intermediate version of the above article. So, as a matter of empirical fact, IR radiation is emitted by GHG in the downward direction. 2) The surface of the Earth has a very high emissivity and hence absorptivity in the wavelengths in which IR radiation is emitted by Green House Gases. This is shown very clearly (from observation) in post 703 by Alexander above. Note, the wavelength of peak emission by CO2 is 15 microns, with the "wings" of peak emission extending from 13 to 17 microns thus showing significant overlap with every type of surface shown, except coarse snow, which of course significantly overlaps with H2O emissions. Thus, over land, the vast majority of Downward Long Wave Radiation is absorbed by the surface, and at sea a significant proportion of it, in most cases the majority of it is absorbed. 3) If a photon is absorbed by a surface, the surface gains the energy that was contained in the photon (by conservation of energy). 4) If energy is absorbed by a surface, all else being equal, the temperature of the surface will rise, and the surface is warmed. 5) However, the surface of the Earth is typically warmer than the atmosphere, so it itself is radiating energy to the atmosphere, and is radiating more energy than it receives from the atmosphere. 6) Therefore, absent any other energy sources, the net effect of the interchange of photons between atmosphere and surface is that the surface cools and the atmosphere warms. 7) However, if the atmosphere was not there, or did not radiate IR radiation: (a) the total energy emitted by the surface would still be the same, because that energy is solely a function of its temperature and emissivity; but (b) the surface would receive less energy because it would not be absorbing photons emitted by the atmosphere. 8) Therefore, over a given period of time, and ignoring all other energy sources, the Earth will cool quicker without an atmosphere containing GHG than it will with one. 9) Of course, the Earth's surface is periodically warmed by a very bright energy source, the Sun. For most locations on Earth, the period it is warmed is for on average 12 hours out of every 24. 10) The amount of energy received from the Sun in any 24 hour period at any location is (to a first approximation) not a function of the temperature at that location. Therefore, the Earth at any location will be warmer if it cools less at night because it will add the Sun's energy received that day to a higher base level. 11) Therefore, because GHG slow cooling, they result in warmer temperatures on the surface of the Earth, not because they are by themselves capable of providing a net warming to the Earth, but because they slow the loss of the energy provided by the Sun. (12) This does not explain the equilibrium temperature of the Earth's surface, which is governed by the need for the Outgoing Infrared Radiation to balance the Incoming Short Wave Radiation, which balance is achieved by the interplay of upper tropospheric temperatures and surface temperatures brought about by the lapse rate and GHG concentrations. Each of (1) through (12) above is straight forward, blindingly obvious, and well confirmed by by being predicted by basic physical laws, and by being observed multiple times. Jointly, they refute your entire case. I am not entering into a discussion on this point out of deference to the moderators request that we not feed the trolls. However, laid out step by step like this, even you, Damorbel, should be able to see what absolute drivel you have been serving up.
91579. CBDunkerson at 00:08 AM on 24 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       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. In short. You give every appearance of knowing that your argument is groundless and not even trying to defend it... save by obfuscating with trivialities; Like using a solar cooker to cool something. Which really applies the same principle in reverse. Infrared energy coming off the object inside the cooker is reflected away towards open space. Provided the cooker is insulated enough to limit IR coming in from other directions and the IR input from the area it is pointed towards is less than the IR being reflected away from the object you get a net cooling effect. This proves that energy can flow from warmer areas to cooler ones... 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). damorbel: I thought your arguments were too ridiculous to be actually believed back when you were just arguing things like 'the reflectivity of an object has no impact on its temperature' and 'electromagnetic waves can only travel from cold areas to warmer areas in large bandwidths'. Now that you've moved on to 'the greenhouse effect is caused by gravity' and the like we clearly live in universes too profoundly different to allow any sort of rational discussion.
91580. Gilles at 23:59 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       "Try reading the IPCC WG1 scientific basis report, it is full of discussion of what is uncertain and in need of further research" My personal experience is that when I'm read the IPCC WGI report, I don't find any certitude concerning the exact role of CO2 in the XXth warming. Although I would also admit that "average temperature" (not really "climate" ) is changing, and that mankind probably contribute to this change. But I'm not going much beyond- and certainly not up to the conclusions that GW is the worst problem in the world. I have no idea of how many scientists would say the same - but actually I don't really care about that.
       Moderator Response:

       [DB] You keep insisting on a simple answer to a complex question and then reject the answers given you without an obvious demonstration that you've objectively tried to understand them.

       If your aim is not to understand the science of climate change but to simply offer up non-science-based rhetoric with no sourced links to substantiate your contrarian positions, then other websites exist to serve that purpose.

       [Dikran Marsupial] You said it would be desirable to "precise what is not enough understood to justify keeping on doing research". The statements of uncertainty in the IPCC WG1 provide you with exactly the precis you want, it is a bit daft to then complain that the IPCC report doesn't provide "certitude". Science isn't about "certitude" it is about assessing the plausibility of the competing hypotheses that remain after you ignore the ones that are inconsistent with the observations. I have pointed out to you repeatedly that there is no proof of any theory regarding causality in the real world, it is fundamentally impossible. If you want certitude, stick to mathematics, or politics (where words like "proof" and "certainty" have weaker connotations).
91581. Arkadiusz Semczyszak at 23:58 PM on 23 March 2011
       Preventing Misinformation
       @dana1981 Cited paper mainly says that there is a problem with the carbon balance for the Holocene - the CO2 from the soil (not only the influence of ancient civilizations agricultural): “However, there are uncertainties in our current study, which provides the guidance for future studies of peatlands and Holocene carbon cycle dynamics. The uncertainties related to our model simulations are mainly caused by the terrestrial vegetation ...” A well, there is a sentence: “However, these uncertainties are not critical to the interpretation of our results, as the overall magnitude of NP carbon uptake is large.” But there are doubts (perhaps the errors - and certainly "not critical"?) - but certainly they are not my mistakes. And 0.5 ppm of CO 2 per year - participate in the unbalanced excess atmospheric CO2 - not a hypothetical value. There are analysis indicating the decisive contribution of natural CO2 Spencer. Spencer only speculate where it is a natural surplus of CO2. Sources shows study a case of Mt. Pinatubo and El Nino in 1997/8. Volcanoes - in total - so far the negative impact on global NPP - ”many years after the eruption”. The same is confirmed - says in this work: Aerosols and the land carbon sink, Angert & Krakauer, 2010. in connection with (contra) to work: Impact of changes in diffuse radiation on the global land carbon Mercado, et al., 2009. The resulting conclusions are most interesting in this paper: Impacts of large-scale climatic disturbances on the terrestrial carbon cycle, Erbrecht & Lucht, 2006. Every sentence is extremely important here: “The amount of carbon dioxide in the atmosphere steadily increases as a consequence of anthropogenic emissions but with large interannual variability caused by the terrestrial biosphere.[...]” “The response of soil respiration to changes in temperature and precipitation explains most of the modelled anomalous CO 2 flux.” “We therefore conclude that during the last 25 years the two largest disturbances of the global carbon cycle were strongly controlled by soil processes rather then the response of vegetation to these large-scale climatic events.” “Atmospheric carbon dioxide measurements show that the rate of increase of atmospheric CO2 varies substantially from year to year ...” “It is widely accepted that these variations are caused by the terrestrial biosphere through the processes of carbon uptake during photosynthesis and carbon release during soil respiration ...” Mt. Pinatubo: “In comparison, variations in the oceans [Two decades of ocean CO 2 sink and variability, Quéré et al., 2003.], deforestation, and land use change are much smaller ...” “Results show that a large fraction of the observed CO 2 growth rate variability is controlled by varying soil organic matter decomposition rather than changing plant productivity [...].
91582. Arkadiusz Semczyszak at 23:55 PM on 23 March 2011
       Preventing Misinformation
       @#IanC “... the biosphere sink somehow distinguishes natural CO2 and anthropogenic CO2.” This is true. But how would "impossible" my scenario? There is no chemical difference (14C/13C/12C) between the old carbon from fossil fuels, the old soil, ventilation of the deep ocean. Thus, if the current warming is unprecedented in the Holocene, unprecedentedly rapid respiration it must be used not only from present NPP - but with the old carbon stocks and ... can not be in balance with the sink - type of biosphere. Decomposition of old organic matter as a result of deeper active layers in a snow depth manipulation experiment, Nowiński et al., 2010.: “Our results indicate that, as permafrost in tussock tundra ecosystems of arctic Alaska thaws, carbon buried up to several thousands of years ago will become an active component of the carbon cycle, potentially accelerating the rise of CO 2 in the atmosphere.” “Radiocarbon ages of heterotrophically respired C ranged from <50 to 235 years BP in July mineral soil samples and from 1,525 to 8,300 years BP [!] in August samples ...” Carbon respiration from subsurface peat accelerated by climate warming in the subarctic, Dorrepaal et al., 2009.: “Climate warming therefore accelerates respiration of the extensive, subsurface carbon reservoirs in peatlands to a much larger extent than was previously thought ...” “Assuming that our data from a single site are indicative of the direct response to warming of northern peatland soils on a global scale, we estimate that climate warming of about 1°C over the next few decades could induce a global increase in heterotrophic respiration of 38–100 megatonnes of C per year. Our findings suggest a large, long-lasting, positive feedback of carbon stored in northern peatlands to the global climate system.” In the past, the main sink for the large surpluses of CO2 has always been a terrestrial biosphere - higher plants - tissue. Organisms tissue always respond (longer process of reproduction) of delay in relation to a unicellular soil bacteria (respiration) or CO2 from the deep ocean ventilation. Hence - L-V model is - for source and sink - especially photosynthesis - the most reasonable. This confirms this paper: Loss of Carbon from the Deep Sea Since the Last Glacial Maximum, Yu et al., 2010. : “Combined benthic δ13C and [CO3 2-] results indicate that deep-sea-released CO2 during the early deglacial period (17.5 to 14.5 thousand years ago) was preferentially stored in the atmosphere, whereas during the late deglacial period (14 to 10 thousand years ago), besides contributing to the contemporary atmospheric CO2 rise, a substantial portion of CO2 released from oceans was absorbed by the terrestrial biosphere.” Only after three thousand. years the biosphere has removed the natural surplus of the early Holocene ... Theory o 100% of the anthropogenic origin of the unbalanced excess CO2 in atmosphere - affect the basics of ecosystem sciences - population dynamics.
91583. Robert Murphy at 23:53 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       "I would much preferred 51% of those democratic peoples to have voted for their leaders, and 51% of scientists to agree on all the main facts of AGW." Comparing scientific consensus to a brutal dictatorship is less than convincing, to say the least. You may "prefer" to have only 51% of climate scientists agree on the main points of AGW, but wishing it doesn't make it so. And imagining that their acceptance of AGW is done at the point of a metaphorical gun is also wishful thinking, because you have nothing to back your wish up with. Reality is not very yielding to our personal preferences.
91584. RSVP at 23:47 PM on 23 March 2011
       The Libertarian Climate Conundrum
       alan_marshall 48 "For example, rather than ration gasoline, it is much better to price it in a way that gives people an incentive to use less..." ...and in this way give the rich the break they deserve? making "draconian control" almost sound attractive. But aside from what might be envisioned here, think about this one moment... If climate were taken back to 1750 conditions, as per hockey stick graph, the world could only need more, not less energy considering the increased winter heating costs that will be needed. (At the same time, less AC waste heat (assuming cooler summers) will also have to be made up in the cooler season.) So it looks like this whole focus on CO2 is pointless. We need more energy period, and if it can be supplied by so called alternate sources so much the better.
91585. damorbel at 23:25 PM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #783 damorbel - & Response: [DB] DB I am deeply dissappointed to have to write this, since my capabilities are definitely 'off topic' and it might be thought that some of the remarks in the cited link are 'ad hominem'. Your link has this :- "I didnt describe any experiment." You must forgive me, I was looking to you to describe an experiment to which I could agree. Next in the link it has:- I proposed that an experiment be designed such that normal understanding of physics and your understanding would calculate a different result." This of course doesn't mean I am abnormal. Then the link has:- "This is normal way to test scientific arguments." I'm afraid I do not quite understand what this means, does it also mean that I cannot achieve a scientific result? And:- "I asked if the experiment didn't go your way," As yet no experiment to 'go my way' Further in the link:- "whether you would be prepared to abandon your view and read the textbook. (ie, behave like a scientist) Interesting question. But I don't know which textbook I am suppose to read or whether it is a requirement for scientists to read text books. Personally I recommend original works, textbook contents are at least 2nd hand if not much more; at university my tutors always advised original texts, they had a low opinion of published textbooks. Finally:- "Got a yes/no? In fact, have you got an experiment that you think validates your views over mainstream physics?" I have set out clearly what the essence of how energy is transferred by means of photons and so far nobody has shown it to be incorrect.
       Moderator Response: [muoncounter] We've heard the one about textbooks before. No need recycling your old ideas when they didn't work first time around.
91586. Ken Lambert at 23:11 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       Ho Chi Minh used to get about 97% vote every time he stood for election. So too did many other leaders of Peoples Democratic Republics. I would much preferred 51% of those democratic peoples to have voted for their leaders, and 51% of scientists to agree on all the main facts of AGW. ( -Snip- )
       Moderator Response: [DB] Off-topic portion deleted.
91587. Kevin C at 23:08 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       SME @15: Well done for bringing up Popper. Have you read Kuhn and Feyerabend? They may give you a slightly different perspective. But actually, I think there is considerable space for the idea of consensus science even in Popper work (especially if we introduce Bayes as well). The naive understanding of Popper is that hypotheses fall into two classes: falsified and not-yet-falsified. Unfortunately that model is so simple as to leave science as almost useless. In practice, scientists constantly assess how much confidence they have in different hypotheses. Popper describes this by asking how many 'severe tests' (tests which could falsify the hypothesis) a hypothesis has survived. The term 'consensus science' may be understood in exactly these terms - when a hypothesis has survived many severe tests, and many alternative hypotheses have failed those tests, then the result among scientists in the field approaches consensus. (All this can be said more precisely in Bayesian probability terms, but I think in practice the social nature of scientific consensus is probably more important most of the time. Hence we are talking about a study on the views of scientists.)
       Moderator Response: Well said, thanks.
91588. Ken Lambert at 22:57 PM on 23 March 2011
       Zero Carbon Australia: We can do it
       Vague #88 Please expand on the role of rare earths in Wind and Solar collectors??
91589. Kooiti Masuda at 22:47 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       The article of Doran and Zimmerman (2009), mentioned by MarkR above (#20 presently), should be taken as the source of the claim "97 out of 100 [active researchers in the field] agree that the climate is changing and that we are causing it". Anderegg et al. cited it. Anderegg et al. derived a similar number by some different statistics as well, but that might not be a fair sample of active climate scientists. Doran's article was also dicussed by Jeff Masters at Weather Underground blog.
91590. Gilles at 22:24 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       So in my opinion, it would be highly desirable to precise what is not enough understood to justify keeping on doing research
       Moderator Response: [Dikran Marsupial]Try reading the IPCC WG1 scientific basis report, it is full of discussion of what is uncertain and in need of further research. The job has already been done, perhaps you ought to read more and post less, at least until you have researched possible answers to your questions (the WG1 report is an excellent place to look for answers).
91591. Gilles at 22:22 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       a remark on this :" If such claims were credible it would be unusual as the divisive nature of scientists would prevent such a large consensus if there actually were grounds for division. However, the substantive point is that there is a general (if not complete) consensus" In my opinion, you defend a very delicate position where the "consensus " must be just large enough to provide evidence that things are "true", but not large enough to justify that you need to argue against "contrarians". The same is true for the whole research in climate science. You need to argue that things are really so well understood that it is unacceptable to contest them, but that we still need to pay for researchers and support climate scientists. That is the really unusual thing - usually we do research when the situation is not yet clearly understood
91592. Gilles at 22:16 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       moderator : I know that this will be soon censored, but this is kind of a private conversation : how can you honestly defend the opinion that the science is proved, if even their best defenders implicitly say the opposite ? and how can you claim that you defend honestly science , if you're not even able to let this question appear and answer it easily ?
       Moderator Response: [Dikran Marsupial] Nowhere have I sais the science is proved, in fact I explicitly said that such proof is fundamentally impossible "You can't prove a theory regarding the real world, only disprove (Popper)". Perhaps you need to read what is written in replies to your posts more carefully (on that topic, your recent comment implies that the 97% consensus is unusual, when if you read the article, it explicitly states that it is not unusual - read the last paragraph). BTW if you want to have a private discussion, email would be a better option, my email address is dikranmarsupial@gmail.com .
91593. chrisd3 at 22:11 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       @22 LazyTeen (is there another kind?): Yes. Consensus is a consequence of solid evidence and hypothesis/theory, not a proof of it. To the standard "skeptic" strawman "Consensus is not proof," part of my resposne is often something along the lines of "No, consensus isn't proof, and no one says otherwise, but it is evidence of evidence."
91594. Gilles at 21:45 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       so what do you understand from : "From my own experience, such a high proportion is quite unusual." which "experience" is he talking about ? a tautology is not "unusual" , usually ...
       Moderator Response: [Dikran Marsupial] As I said, it would only be unusual if the claims against the consensus view were credible. If such claims were credible it would be unusual as the divisive nature of scientists would prevent such a large consensus if there actually were grounds for division. However, the substantive point is that there is a general (if not complete) consensus, so please move on to a discussion on the substantive issue, rather than quibbling irrelevant details.
91595. damorbel at 20:45 PM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #782 scaddenp you wrote:- "still waiting to hear whether you accept that experiment is way to settle the debate." Not at all sure what experiment you have in mind. Care to describe it?
       Moderator Response: [DB] The question here, which you have conspicuously avoided answering for some time now, makes it clear that the experiment design to prove your alternative world of physics is up to you. We're still waiting.
91596. Marcus at 20:35 PM on 23 March 2011
       The True Cost of Coal Power
       BTW, Gilles, your data regarding Germany's per capita CO2 emissions is almost 4 years old. Back in 1991-before they embarked on their renewable energy & energy efficiency program, their emissions were 12t per capita-so a 3.4t per capita reduction in the space of 15 years-with no apparent harm to GDP growth (per capita GDP of around $41,000). The US, btw, that has double the CO2 emissions (per capita) of Germany has a per capita GDP of only $47,000. Denmark, Sweden & Norway also have significantly lower per capita emissions than the US, yet their per capita GDP is *higher* than the US ($55,000, $49,000 & $88,000 respectively). The UK & France have *also* reduced their CO2 emissions-by around 1t per capita from 1991 levels-& they also have very good per capita GDP ($36,000 & $39,000 respectively) really kind of puts paid to the whole Fossil Fuel use=greater wealth argument. Anyway, like I said, I'll now leave you to dwell in your fantasy land. Just please stop spamming your fantasy around this site *unless* you have some kind of solid proof to back it up.
91597. LazyTeenager at 20:18 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       It's a standard climate skeptic debating point to express contempt for a "consensus of climate scientists". My standard answer to this is that it is not just a consensus of points of view. It is much stronger than that. It is really a "consensus of evidence".
91598. Gilles at 20:09 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       19 Philippe : maybe you can give a constructive opinion of why a 97 % agreement is considered as "unusual" , for a proven theory ?
       Moderator Response: [Dikran Marsupial] You can't prove a theory regarding the real world, only disprove (Popper), so your question is based on a fundamental misunderstanding. Taking that into account, the question becomes "why is a 97% agreement considered as "unusual" for a generally accepted theory?" then the question is merely a tautology posed as a question. As the article suggests, scientists pick holes in theories for a living, so 97% consensus would be unusual if the generally accepted view didn't have good support from the theory, experiment and observation. Thus the 97% consensus would be unusual only if the skeptic objections were as solid as presented on e.g. skeptic blogs. In my view, it isn't unsual.
91599. scaddenp at 20:00 PM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Damorbel - still waiting to hear whether you accept that experiment is way to settle the debate. Sounds like you only want to talk, not find anything out.
91600. MarkR at 19:41 PM on 23 March 2011
       Why we have a scientific consensus on climate change
       rhjames: check the link you were first given! The 97% was originally from a small sub-section of those polled by Doran & Zimmerman for a 2009 paper. Anderegg, 2011 found about the same figure using different methodology, as explained in the post.

Prev  1824  1825  1826  1827  1828  1829  1830  1831  1832  1833  1834  1835  1836  1837  1838  1839  Next