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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 81951 to 82000:

  1. Infographic: 97 out of 100 climate experts think humans are causing global warming
    Eric @198, No. I'm flattered, byut my simple analysis of BPL's data is really not something you should be using to bet. Also, look at Knutti and Hegerl, the PDF is not symmetrical, it is skewed towards the high end. And AGW is not a betting game.
  2. The Planetary Greenhouse Engine Revisited
    Re Michele - the mesosphere on Earth is not convective. It is less stable than it would be with a zero or negative lapse rate, but there isn't much convection there. Generally, the convection that does occur in the Earth's stratosphere and mesosphere is thermally-indirect motions (heat pumps) forced by kinetic energy produced by thermally-direct motions (heat engines) in the troposphere; the kinetic energy - actually the fluid mechanical energy which is a combination of kinetic energy and APE (although the ultimate conversion of remaining kinetic energy to APE is the heat pump part) in the form of fluid-mechanical waves, propogates upward as gravity waves, equatorial waves of various types (associated with the QBO; I haven't read of this being thermally indirect or driving meridional overturning but I would think it has to be thermally indirect), and Rossby/PV waves (associated especially with the Brewer-Dobson circulation within the stratosphere and 'sudden stratospheric warmings'). The energy is absorbed above when and where kinetic energy is dissipated mechanically (mechanical damping of the waves) and otherwise converted to APE in thermally indirection motion with the resulting APE being dissipated radiatively (thermal damping of the waves). Really, we can think the CO2 molecules behave as heat engines which, colliding with the surrounding molecules, absorb thermal energy from them, and transform it to EM energy....Both the gradients are negative because the continuous growth of the geo-gravitational energy that phagocytizes them. So, the rising CO2 molecules never are in LTE, the thermal energy (needed to excite them until the resonance) is used for other different purposes (the rising of the entire air particle), and there can’t occur any radiative emission. ... The surface temperature is determined by the lapse rate and above all be the altitude where the rising air particles are stopped by the inverted slope due to the external radiative heating of a layer of the atmosphere above it. No, very much wrong and confused, sorry. The tropopause level doesn't necessarily or generally correspond to the effective emitting level. The fact that you can see spectra where some freqencies have brightness temperatures higher than the tropopause temperature should alone be a clue. Note also that the CO2 band is not only that part with the lowest brightness temperature; it extends outward from there. Same for water vapor, too. See 374 http://www.realclimate.org/index.php/archives/2011/06/unforced-variations-june-2011/comment-page-8/#comment-208838 383 http://www.realclimate.org/index.php/archives/2011/06/unforced-variations-june-2011/comment-page-8/#comment-208856 and some clarifying comments in between. Of course, also the surface radiation around 15μm forces and excites the CO2 molecules which could scatter it. I think this isn’t the case, otherwise, the brightness temperature around 15μm should be higher. The CO2 fully wastes the EM energy to heat close the ground and this can be partially converted back and emitted to space only at the top of the first convective layer above the ground. Actually near the center of the CO2 band, it is so opaque that much/most of the radiation emitted at the tropopause level is absorbed, relatively nearby. The net LW flux at the tropopause is or is close to zero; the effect is or nearly is saturated. Adding CO2 doesn't have much effect on the tropopause radiative forcing at the center of the band. It DOES have an effect a bit outside the center of the band, where it's opacity is intermediate (it will also have some indirect effect as stratospheric adjustment will affect the downward flux from stratospheric water vapor and ozone as well as CO2). The opacity for a given level of CO2 drops roughly exponentially away from the band center, which is why each doubling of CO2 effectively widens the band by a given amount and has a corresponding amount of radiative forcing (if there were only a tiny amount of CO2 then the band center wouldn't be saturated and the forcing would tend to be more linearly proportional to CO2 amount; for the amount of CO2 on Venus, other bands become important and the proporitionality if forcing to amount of CO2 is different again. (Also, the climate itself affects the forcing per unit amount change - different wavelengths have different relative importances at different temperatures; the radiative fluxes change; there are variations in water vapor and cloud overlap on Earth (etc. for Venus, though I'm not sure how the feedbacks work there), and the vertical temperature profile is important. Also there are variations in line broadenning and line strength, ... etc.)
  3. Eric the Red at 11:30 AM on 21 June 2011
    Infographic: 97 out of 100 climate experts think humans are causing global warming
    I am not picking anything. These are the ranges chosen by the three other posters. Betting under 2 appears to have a similar likelihood as over 4.
  4. When scientists take to the streets it’s time to listen up
    ClimateWatcher @3 "Taking to the streets is an emotional exercise." Actually it is a political exercise - an attempt to draw public attention to an issue. That issue is the campaign by vested interests and certain political blocs to obscure or misdirect the message that AGW is real. The current denialist line is that the science is not consistant or conclusive. Doubt is cast over every detail the business as usual advocates can find but no consistant alternative thesis is put forward. Scientists are frustrated that their work so far is not being fairly reported. They've done (and continue to do) their work with regard to the science. The new task is to get the message out to the public because media and political policy makers have laregely failed to do so. Your comment suggests that scientists are not entitled to the same political rights as other members of the community.
  5. The Planetary Greenhouse Engine Revisited
    Re 20 guinganbresil - I think that's an interesting issue and I tried to estimate some things myself at another post - I think it was in comments at an earlier post by Chris Colose on his own blog. Perhaps a scale analysis (this may be over or underdetermined and there may be some errors, but at least this gives a sense of what might be done): U ~ L/T, Area ~ L^2, heat flux ~ R*L^2, where R is *a* radiative forcing, heat flux between hemispheres ~ U*L*(Th-Tc)*H*cp*density, rate of kinetic energy production by horizontal motion ~ L*H*U*L*(ph-pc) = U*H*L^2*(ph-pc) where ph-pc is a representative pressure difference between the cold and hot side and proportional to Th-Tc (at surface the difference will have an opposite sign than at the top of the overturning layer of depth H - or H could be an e-folding scale), kinetic energy supply ~ R * L^2 * 1-Tc/Th, viscous kinetic energy sink ~ viscosity * L^2 * U/H - or is it U^2/H, or U/H^2, I'll have to get back to that... mixing kinetic energy sink (mixing heat downward) ~ ? (could be negative or zero on the hot side - or incorporate thermally direct localized overturning on the hot side into the mixing term, and it would be negative if the export of heat by horizontal winds is sufficient to maintain a greater than adiabatic lapse rate), Actually I need to go back and specify R farther; Rh could be the net radiant heating of the surface in the warm hemisphere; Rc could be the radiant cooling of the surface in the cold hemisphere; 1-Rc/Rh ~ (1-Tc/Th), except that whatever kinetic energy is produced is eventually converted to heat anyway, which in terms of necessary heat flux would be divided into an addition to Rc on the cold side (kc) and an effective addition to Rh on the warm side (kr) so that for the actual Rc and Rh, 1-(Rc-kc)/(Rh+kr) ~ (1-Tc/Th), and Rc-kr = Rh+kr ... no wait, that can't be right... Rate of conductive heat supply to surface on cold side ~ L^2 * (THc-Tsurfacec)/H * K , where THc is the temperature at height H above the now go play with it. Some of the above clearly needs more work, but some things are clear: Note that you could have overturning with cold air masses sliding under warm air masses without actually having an adiabatic lapse rate. In fact, that kind of overturning decreases the lapse rate. With cold air coming in over a warm surface you could get something more like a troposphere, and perhaps some stable layer of air in the 'winter/night' hemisphere/region would be considered part of the global tropopshere as it is on Earth (although the troposphere is still not as stably stratified as the stratosphere - except maybe (I'm not sure) in the inversion near the surface, which is not the whole troposphere). However, in the polar nights on Earth, the troposphere, heated by horizontal import of warm air from warmer places, can lose that heat to the surface by radiation and conduction/mixing and can lose that heat to space (and the stratosphere) by radiation as well. With no greenhouse effect (specifically of the emission/absorption kind), the troposphere cannot cool by emitting radiation, and so either it must be warmer or the surface must be cooler to get the same heat flux, which must be entirely to the surface. Kinetic energy from the large scale overturning may drive downward mixing of heat; otherwise you have to rely on conduction/diffusion. Possibly the lapse rate would be such that the stratosphere does reach the surface. The troposphere might perhaps be a bubble on the hot side, which may extend somewhat into the night/winter side. The depth of the overturning layer in the night/winter side must be small enough for conduction to make up for what mixing cannot accomplish, to balance the heat supply - itself limited by the depth of the layer and the wind. Thus the layer may tend to be shallow. The tropospheric thickness on the hot side would be determined in part by the supply of cold air from the cold side, which would be determined by the wind speed and the depth of the layer which can lose heat to the surface at the necessary rate. So the troposphere on the hot side may also be forced to be shallow. If there is any solar heating of the air itself, this also has to be mixed and/or diffused/conducted downward.
  6. When scientists take to the streets it’s time to listen up
    @3, ClimateWatcher: "Cold rationality" - clearly you are not a scientist, and have never participated in a "vigorous" scientific debate ! I also dislike your attitude of "Scientists should be seen and not heard", and find it rather patronizing. Getting back to the article itself, and attacks on scientists in general, what we are witnessing now is comparable to the Catholic church's attacks on heliocentrism, and to the Nazi's campaign against "Jewish Science". Fortunately, it has not reached the intensity of those attacks, but with trillions of dollars and political power at stake, I fear for the safety of all working scientists, particularly those with a high media profile.
  7. Infographic: 97 out of 100 climate experts think humans are causing global warming
    But evidence we have is that cloud feedback is near neutral. There is uncertainty but below 2 is not the way to bet.
  8. Climate change denial and the abuse of peer review
    Nice piece overall, but:
    What happens to data if successive annual values are subtracted from each other? This mathematically removes any linear time trend. In other words, temperatures could have doubled every other year and it would have escaped detection by the authors.
    Doubling every other year is not a linear trend.
  9. Linking Extreme Weather and Global Warming
    Some have stated I am a "Cherry Picker" on posting historical weather events. I look at the history of each area that is considered a major deviation and look at some historical information on that area. I looked at the history of Pakistan floods and severe flooding is not so extreme as it seems to happen often enough. I would like someone to define what an "extreme" weather event is so research can progress to see if weather anomalies are really getting more extreme in a warming world. What would constitute an extreme rainfall amount? What is an extreme temperature? Name an extreme weather event that occured this year so I will not be blamed for cherry picking.
    Response:

    [DB] "I looked at the history of Pakistan floods and severe flooding is not so extreme as it seems to happen often enough."

    Umm, you may want to try reading your posts before submitting them.  Because you're saying the record-setting floods of 2010 happen often enough...

    Actual analysis instead of the Eyecrometer is called for.

  10. The Planetary Greenhouse Engine Revisited
    Re guinganbresil - If you made the atmosphere transparent below the cloud deck, and the temperature of the surface were sufficiently high, so that the heating of the cloud deck by radiation from the surface were sufficient, if the cloud deck were completely burned off as a result, then the surface radiation would simply go off to space (unless there's another cloud deck or some other source of opacity above) - furthermore, the backradiation at the surface from the original cloud deck would be lost. The net LW (radiant) cooling of the surface would be increased, which would be taken away from energy available for convection. The net LW flux at the tropopause level (above convection) would increase, cooling the whole surface+troposphere, so even if the lapse rate were maintained, the surface temperature would fall. This is setting aside the effect on solar radiation. The burning off of a cloud deck is a feedback of the same category as water vapor feedback and surface albedo feedback. Lets' keep the cloud deck and see what happens. The increased net LW flux in the space between the surface to the cloud deck must be balanced by a reduction in convection - if the convective flux was originally not big enough, convection could go to zero and the lapse rate could decrease, creating a stable layer and necessarily tending to reduce surface temperature while increasing the temperature at the cloud deck. But looking for what happens at equilibrium, it's easiest to get to the effect at the tropopause level and then get back to convection. Even if there remains some convection beneath the cloud deck and the surface temperature is sustained, the cloud deck must then get warmer and the emission from the top of the cloud deck will increase. This will tend to increase the net LW flux out of the tropopause and out to space (effect modulated by absorption by overlying layers). Thus this situation cannot be sustained; energy is being lost from the troposphere and surface; there must be a temperature reduction. If both the cloud deck and surface remain in/adjacent to the troposphere, the nonlinear relationship between temperature and emission will reduce the net LW flux from the surface to the cloud deck. Whether or not the reduction is sufficient to allow convection to be the same or greater than it was originally (before removing opacity from the space between clouds and surface) is not determined as this description is too general.
  11. Climate change denial and the abuse of peer review
    I read the Stoat summary wrong. It certainly seemed highly unlikely that Happer would ever recommend rejection of a Lindzen paper. So Lindzen's argument boils down to the fact that he doesn't appreciate an independent review (that could improve the quality of his paper) or scrutiny of the qualifications of his reviewers. What's more revealing is that while the rejection of Happer was due to his insufficient expertise on the subject matter and Chou's rejection related to his collaboration with Lindzen on Iris (conflict of interest), Lindzen rejected 2 suggested alternate reviewers on the basis of: "Both are outspoken public advocates of alarm, and Wielicki has gone so far as to retract results once they were shown to contradict alarm." How professional - this after claiming the Happer rejection justification was "libelous". One of Lindzen's alternate reviewers (Minnis) was said to be chosen. Lindzen then characterizes the paper being rejected in the end only because it was too long. Yet all 4 reviews noted: Suitable quality: No (x4) Conclusions justified: No (x4)
  12. Who's your expert? The difference between peer review and rhetoric
    Peer review is gatekeeping but does it keep out error? Peer review is review by a few selected (by who?) for their expertise. Only if published is a Paper exposed to wider peer review. Above all, peer review is the very foundation on which science moves forward and, without being able to rely on it, science in its many areas of research could not be accepted as being error-free based on current knowledge. Little wonder then that those who do not expose their work to peer review or could not pass it if they did should attack it – and be resisted. But does this mean that it is always right or, for science, the best of all possible worlds?
  13. Philippe Chantreau at 09:44 AM on 21 June 2011
    Climate change denial and the abuse of peer review
    Thanks once again John for pointing out the obvious. Deep Climate has extensively analyzed works by Wegman and found substantial problems of plagiarism and what could only be described as academic shortcomings. They also have a in depth discussion on Wegman's use of the atrocious McIntyre and McKitrick paper that was used to try to convince the gullible that Mann's methods generate hockey sticks out of random data. It is truly a work of art in deception. I am yet to hear anything from skeptics about it that would make sense.
    Response: [JC] Note - Steve Lewandowsky wrote this article. I'm just reposting it from The Conversation website.
  14. There's no room for a climate of denial
    Tom Curtis @98 Your overall point "My point is, however, that this is not a reason for denial in any person, or at least it is not a substantive reason." I totally agree with you on this. Most people do not seem to be scientifically literate (at least from my experience) very few would read a peer-reviewed climate article for themselves. They rely on Media to help them understand complex issues they do not have time or interest to explore at greater depth. I was posting that to explain why people are losing interest in Climate Change science and switching to a denial state of mind. On this thread you have two video posts Albatross @28 and Daniel Bailey @39. Both are expamles of using an emotional appeal to sway a mental state. "Do you want to be a blind idiot and drown even as we try to save you....severe denial" From Albatross video. Or tornado in Joplin connected to Climate Change. I read articles here daily but rarely post. The Daniel Bailey video started my posts because it so closely resembled arguments I have had on Conspiracy sites when individuals claim all bad weather events are HAARP induced. The HARRP posts are what started me looking at Historical weather events to see if things really are getting worse today. So far I have not found enough evidence on this site to verify this sentiment or any other site.
    Response:

    [DB] This site keeps its focus on science, not on tin-hat-isms.  Please keep that in mind when constructing your comments.

  15. Infographic: 97 out of 100 climate experts think humans are causing global warming
    Eric the Red - Given the best evidence we have to date, the climate sensitivity could be under 2ºC. It could be over 4.5ºC. Our evidence indicates that it's most likely about 3ºC. You seem to be picking strictly from the lower estimates, of low probability - you might as well pick from the high estimates of low probability. Neither is a sensible choice.
  16. When scientists take to the streets it’s time to listen up
    I've been searching for it, but cannot find it - a cartoon that speaks to this topic: A man in a lab coat, looking a lot like Einstein, comes out into the hall with a horrified expression and a sign saying "The End Is Near!". Two other lab-coated men in the foreground look at this, one remarking "I don't like the looks of this..." When those scientists who actually know the subject under consideration take to political demonstrations, that means they have something to worry about!
  17. Climate change denial and the abuse of peer review
    NewYorkJ - I believe that Will Happer was outright rejected by the PNAS editors (as was Chou, Lindzen's co-author on the 2001 "iris" paper); Lindzen suspects that one was Minnis; another might have been Ramanathan. The other two apparently came from the editors original suggestion list.
  18. Introducing the Skeptical Science team
    Thanks for this page, John. Its good to be able to put faces to some of the names of folks who have so helpfully and patiently answered my questions. This site is a great resource for those of us without a science background and I've handed out a few copies of "The Scientific Guide to Global Warming Skepticism" to freinds who have shown genuine interest in learning about what the science actually says.
  19. Eric the Red at 08:49 AM on 21 June 2011
    Infographic: 97 out of 100 climate experts think humans are causing global warming
    scaddenpm the reason many lower ranges are below 2.0 is the uncertainty of the cloud feedback, which could be a large negative. It is not undiscovered, just unknown with enough certainty to enforced a higher limit. That is just one, there are others. The 95% ranges for the three previous analyses are 1) 1.5 - 5.0, 2) 1.7 - 4.9, and 3) ~0.1 - 5.1. There are several others with their own ranges. These are just three. This is why I cringe whenever someone makes a claim that the climate sensitivity is a certain value and then makes projections based on that. Hence, I disagree with anyone who makes such a claim.
  20. Infographic: 97 out of 100 climate experts think humans are causing global warming
    The range of sensitivities (ie constrained by physics) is much lower than that found in empirical estimates of sensitivities as you would expect. The important point is that empirical estimates are consistent with model estimates. A sensitivity of less than 2.0 requires a so far undiscovered negative feedback.
  21. Linking Extreme Weather and Global Warming
    Camburn @110, "Charlie A posted from the Univiversity of Florida. I am sure their work is sound concerning hurricane intensity and quantity. It looks like you are dismissing this work because it does not agree with your perception. We are getting our wires crossed, my apologies. At #109, I was referring to Norman's comment @70 about the hydrological cycle, not to the ACE index.
  22. When scientists take to the streets it’s time to listen up
    "Science is an exercise of cold rationality." When your fellow citizen's would rather believe in fairies than see a problem coming, then the rational thing to do might well be hit the streets. Imagine predicting an earthquake and keeping it a learned journal without telling the citizens. When the earthquake struck, how would the citizens feel? In this case, the scientist can at least say "well we tried but you were too deep in your political shell to listen".
  23. CO2 Currently Rising Faster Than The PETM Extinction Event
    Rob, Karsten Kroeger works in same section/team as me. So, yes. I am Phil Scadden at GNS Science. Just email me.
  24. Climate change denial and the abuse of peer review
    So it seems all 4 reviewers rejected L&C (Jan. 19, 2011 message), and 2 of those reviewers were recommended by Lindzen, one which included Will Happer (of all people)? Did anyone visiting the WUWT zoo point that out?
  25. davidpalermo at 07:57 AM on 21 June 2011
    Introducing the Skeptical Science team
    I too am very grateful for this site! I am using it more and more as a main source of credible information. Or when I can't figure something out I usually start here. Keep up the good work!
  26. Infographic: 97 out of 100 climate experts think humans are causing global warming
    Albatross - Quite clear, thank you.
  27. Climate change denial and the abuse of peer review
    Would the disgraceful mixing of the pseudo-scientific and ideology (with the emphasis on the latter) produce a form of denial belief-system called Scientology...if that name hadn't already been taken, off course !
  28. Infographic: 97 out of 100 climate experts think humans are causing global warming
    KR and Eric, I did not see the point of undertaking a rigorous stats analysis of the papers involved. Annan and Hargreaves however have looked at the upper range of climate sensitivity. They determine that: "A+H [Annan and Hargreaves]combine three independently determined constraints using Bayes Theorem and come up with a new distribution that is the most likely given the different pieces of information. Specifically they take constraints from the 20th Century (1 to 10ºC), the constraints from responses to volcanic eruptions (1.5 to 6ºC) and the LGM data (-0.6 to 6.1ºC – a widened range to account for extra paleo-climatic uncertainties) to come to a formal Bayesian conclusion that is much tighter than each of the individual estimates. They find that the mean value is close to 3ºC, and with 95% limits at 1.7ºC and 4.9ºC, and a high probability that sensitivity is less than 4.5ºC. " Good enough?
  29. Climate change denial and the abuse of peer review
    The same column referred to in the Lindzen goes Emeritus link, written by Chip Knappenberger based on information from Lindzen, also showed up at WUWT June 9th - complaining that Lindzen had received special treatment that led to his paper being rejected by PNAS (twice), and before that from GRL. Discussion (ahem) ensued. Lots of "conspiracy" claims, criticisms of L&C rejected based upon Lindzen's "authority" in the subject compared to anonymous posters (basic "argument from authority"), many references to the "warmistas" and the "Team"... about what you might expect. The rejected papers are referenced here, the PNAS reviewers comments are referenced here, where I posted them on an earlier Lindzen & Choi thread. (Note - I did miscalculate the impact factor/citations for E&E in that post, typing too quickly and not checking my reference)
  30. Linking Extreme Weather and Global Warming
    Rob @112. Thanks for trying, but I'm sure your post will fall on deaf ears. I have tried to relay this point countless times...but they just keep repeating the same old tired mantra..."the climate has changed before, there have been extremes before, so ergo we do not have anything to be concerned about". Hmm, wonder how many people there were in the early Holocene? Hmm, ~10 billion of us expected later this century, many of them who are not free or have the ability to move as our predecessors could. As you can see from #111, they will not concede that they were wrong. What matter in their own back yard (if it fits their beliefs) will do just fine. ENSO teleconnects differently for different regions, and even differently for different parts of the USA. So we have no way of validating this claim. And yet another statement of fact with unsupported links. This is the NOAA/NWS/CP latest weekly assessment. Camburn claims that the recent La Nina will continue to affect his region until October or November. This is what the IRI have to say: "These observations indicate the presence of neutral ENSO conditions. Because the atmospheric component of the episode was so strong and long-lasting, however, some of the climate conditions associated with La Niña may continue to a mild degree through late June." And here is what CPC/NCEP has to say in their latest assessment: "Collectively, these oceanic and atmospheric anomalies reflect a transition to ENSO-neutral conditions, but with lingering La Niña-like atmospheric impacts, particularly in the global Tropics." Nothing about impacts lingering into the fall over the USA. So the WMO, IRI and NOAA (and affiliates CPC, NCEP, NWS) are all in general agreement, and nothing in that NOAA assessment about affects of the recent La Nina continuing into the fall. I think Mr. Camburn ought to send a very strongly worded letter to them arguing that they are wrong.
  31. Infographic: 97 out of 100 climate experts think humans are causing global warming
    Eric the Red The IPCC states that "...‘equilibrium climate sensitivity’, is likely to lie in the range 2°C to 4.5°C, with a most likely value of about 3°C. Equilibrium climate sensitivity is very likely larger than 1.5°C.". (Emphasis added) As per IPCC definitions: "Likely" > 60% probability "Very likely" > 90% probability So yes, that math has been done.
  32. Bob Lacatena at 07:10 AM on 21 June 2011
    Climate change denial and the abuse of peer review
    I can't wait to see what our resident skeptics have to say on this one.
  33. Rob Honeycutt at 07:00 AM on 21 June 2011
    Linking Extreme Weather and Global Warming
    Camburn... I think miss the entire point of, not only this conversation, but the entire issue of climate change. No one disputes that the planet has likely been about where we are right now during the Holocene optimum. The whole point is that natural forcing and feedbacks should have us on a gradual cooling trend in line with the past 6000 years. But we are seeing a rapid rise in temperature. The issue is not whether the planet has seen something like what we are currently seeing now. The whole issue is, if we continue changing the radiative balance of the atmosphere, what do we expect to happen? What kind of world are we bequeathing to our children and grandchildren?
  34. Eric the Red at 06:54 AM on 21 June 2011
    Infographic: 97 out of 100 climate experts think humans are causing global warming
    Yes, I know BPL had a list which included a half dozen papers below 1.0, and 3 above 5.0. Neither of these convince me that it is below 1 or above 5. Does it convince anyone else. The range is quite large, mostly due to the large uncertainties associated with the various feedback loops. Much more work is needed in this area in order to narrow the range. Albatross, you display a one sigma uncertainty. Have you done the math for the 95% range.
  35. Climate change denial and the abuse of peer review
    A recent case with Lindzen: L&C, GRL, comments on peer review and peer-reviewed comments A very recent case with Lindzen: Lindzen goes Emeritus
  36. David Horton at 06:31 AM on 21 June 2011
    When scientists take to the streets it’s time to listen up
    Climate Watcher succinctly summarises the denier approach. It is fine for the denial industry to use every resource available - massive media support, energy company funding of "think tanks" and denier groups, members of parliament, production of bots to infect threads, shock jocks manufacturing outrage - but they don't want any opposition to that very successful campaign, so scientists should just stay in their laboratories quietly and objectively. Not seen and not heard. Hey, they might not even exist. The Lynas thing is a confluence of two forces. One is the same as the CW approach. Any time we can find any group with environmental concern involved in any way with the IPCC process, why, we will protest loudly.Groups concerned with the environment obviously have no business being concerned with the environment. So we will kick any head that emerges, that will make people wary of using people with environmental concern in any capacity at all. Job done. The second strain is the nuclear one. The nuclear promoters have seen in the climate change concern the ideal vehicle to ram home nuclear power as a solution overcoming all the concerns that people have about it. if you don't want nuclear power then you can't, obviously, be seriously concerned about climate change, goes the line. But simultaneously they have to block any attempt by people supporting renewable energy to put the case. pretend that there is no possible way renewable energy can do the job. Especially "80%". So shoot the messenger.
  37. Linking Extreme Weather and Global Warming
    Oh yes, I am sure the WMO knows more about La Nina and its affects on the US than NOAA does. (NOAA predicts that the affects of the La Nina will continue into Oct/Nov for my area).
  38. Linking Extreme Weather and Global Warming
    Albatross: My cognitive abililty is quit good. I do not miss the point at all. I look at historical events verses recent events and can see no change in intensity nor pattern. What you call a strawman arguement happened. Both on the Mississippi and in Rusia during the time frame indicated. This thread is about AGW and extreme events. As of yet, which is readily admited by the authors of the papers posted is that their is not a correlation between the two. I can tell that you are totally missing the point over and over again. Charlie A posted from the Univiversity of Florida. I am sure their work is sound concerning hurricane intensity and quantity. It looks like you are dismissing this work because it does not agree with your perception.
  39. Infographic: 97 out of 100 climate experts think humans are causing global warming
    Eric, Re the estimate of climate sensitivity, you say "One or two papers" Oh good grief. Come on that is a very, very weak argument, you have to do better than that if you wish to make a compelling case. BPL provides a summary of 61 papers (between 1896 and 2006) that calculate estimates of climate sensitivity. It is by no means comprehensive or up to date, but is shows your statement to be demonstrably wrong. FWIW, the mean is of the 61 papers is ~+2.9 C (plus/minus one sigma 1.4 to 3.9 C)and the median is ~+2.6 C, compare that with the best estimate of +3 C reported in the IPCC AR4. And that is for doubling, we will very likely treble CO2 if we continue with BAU.
  40. Linking Extreme Weather and Global Warming
    Camburn @65, "The link you posted to river trends is really about worthless" I see, but a glib dismissal of the science is not convincing, not scientific and neither is referring us to an anonymous poster on another thread--science is not overturned that easily. Unbelievable that you unquestioningly and uncritically and unskeptically accept what Charlie A writes on the internet versus a paper published in a journal. Please stop this nonsense. From Min et al. (2011, Nature): "Here we show that human-induced increases in greenhouse gases have contributed to the observed intensification of heavy precipitation events found over approximately two-thirds of data-covered parts of Northern Hemisphere land areas. These results are based on a comparison of observed and multi-model simulated changes in extreme precipitation over the latter half of the twentieth century analysed with an optimal fingerprinting technique. Changes in extreme precipitation projected by models, and thus the impacts of future changes in extreme precipitation, may be underestimated because models seem to underestimate the observed increase in heavy precipitation with warming." The you make this truly bizarre, but telling, statement: "People are suggesting extreme events are a somewhat recent occurance? How about the floods of the Mississippi River in the 1920's? The recent floods did not break those records. Or the heat waves and fires in Russia when Tchaivosky was creating beautiful music." A beautiful strawman argument,and quite offensive to the informed reader. In fact, it is quite disingenuous. You continue to miss the point--your behaviour and reaction to scientific evidence that does not support your opinion is really starting to look like cognitive dissonance on your part. You just keep repeating the same mantra, over and over again-- that does not make your opinions correct. Please read my post @64 again. Also read the comment @68,and the posts @104 and @105.
  41. Linking Extreme Weather and Global Warming
    Camburn @20, "1. There is an 8-12 month lag time for the effects of La Nina and what precip and temp will do." and the very next post Camburn @21 "The effects from the current La Nina cycle will prevail for another 4-6 months in the USA." Make up your mind. Now what do the experts say? From the very first paragraph of Trenberth et al. (2002): "Following an El Nino the global surface air temperature typically warms up by perhaps 0.1C with a lag of ~6 months [Newell and Weare, 1976; Pan and Oort, 1983; Jones, 1989; Wigley, 2000]. In an exceptional event such as the 1997–1998 El Nino the amount exceeds 0.2C. Christy and McNider [1994] and Angell [2000] show that the entire troposphere warms up with an overall lag of 5–6 months, but the lag is slightly less in the tropics and is greater at higher latitudes" Trenberth (2002) found lag of 3 months: "The lag of global mean temperatures behind N3.4 is 3 months, somewhat less than found in previous studies. In part, this probably relates mostly to the key ENSO index used...." From a WMO release on 23 May 2011: "However, climate conditions over the next 1 to 2 months may continue to be La Nina-like for some regions, because the atmospheric aspects of the event may decay more slowly than the cool tropical Pacific waters, particularly for this La Niña in which the atmospheric indicators have maintained considerably greater strength than the oceanic ones." Are you going to admit error, or do the leading scientists and WMO have that wrong too Camburn? Either that or you now need to argue your opinions with Polyak et al., Trenberth and the WMO.
  42. Linking Extreme Weather and Global Warming
    Camburn @65, You need to actually read the literature provided to you. And you choose to miss the point of the Arctic paleo study. From Polyak et al. (2010): "Nevertheless, episodes of considerably reduced sea ice or even seasonally ice-free conditions occurred during warmer periods linked to orbital variations. The last low-ice event related to orbital forcing (high insolation) was in the early Holocene, after which the northern high latitudes cooled overall, with some superimposed shorter-term (multidecadal to millennial-scale) and lower-magnitude variability. The current reduction in Arctic ice cover started in the late 19th century, consistent with the rapidly warming climate, and became very pronounced over the last three decades. This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities." From an interview with Polyak: "The paleo data we have so far is very scant, so we can’t know for sure when the Arctic was ice free in the summer last time. To be conservative, the closest candidate is the early Holocene (roughly ~10 kyr ago), when the insolation in the Arctic was high due to the beneficial orbital configuration; however, the more data I see, the stronger is my impression that there was not that little ice at that time. The next best (actually, better) candidate is the Last Interglacial, about 125kyr ago, again due to orbitally-driven high insolation: the ice was likely very low, but we can’t say whether it was completely ice free in summer or not. There are also a few other major interglacials, which may have had a similar picture, in particular Marine Isotopic Stage 11, about 450 kyr ago. In any case we are talking about very rare events controlled by a forcing very different from today. If none of those intervals was really ice free, then a million year assessment would be correct." From SkepticalScience, "In sum, although natural factors have always influenced the state of Arctic sea ice, research strongly suggests that today's decline is driven by the novel influence of anthropogenic CO2 we've added to the atmosphere and thus is unique in Earth's history." From the first line of the abstract in the paper you provided @65 regarding impacts of changes for one small portion of the Canadian Arctic (not the whole Arctic, or the globe). You insist on missing the point, and miss the point of relatively large amplitude local changes versus changes over much larger regions and/or global changes. I do not know how to communicate this fact to you. Maybe you should engage Polyak and argue with them? I do not suspect that doing so would go well for you though.
  43. Infographic: 97 out of 100 climate experts think humans are causing global warming
    Eric the Red - Here's the search I mentioned in my previous post. I believe this an adequate response to your statement of "premises based on one or two papers".
  44. Infographic: 97 out of 100 climate experts think humans are causing global warming
    Eric the Red - In regards to this particular issue, climate sensitivity, it's not "one or two papers". The Climate sensitivity is low thread contains a dozen representative papers alone. See also the IPCC report at this link, additional information here, with specifically observational work described here. A Google Scholar search on "climate sensitivity estimate", limited to just the last 10 years, no patents, and {Biology, life sciences, environmental sciences / Chemistry and materials science / Physics, astronomy, planetary science} only (as a reasonable set of restrictions), gives ~68,400 matches. Out of that list I believe there are perhaps a couple of dozen papers that claim sensitivities below 1.5C/doubling of CO2, most of which have already been refuted. You appear not to be looking at the considerable body of evidence. Even beyond that, the limits of uncertainty on sensitivity, while broad, have serious implications at both extremes.
  45. When scientists take to the streets it’s time to listen up
    Eric the Red: "I have seen that happen repeatedly here." "Oftentimes the websites do misrepresent the paper." Do you have examples from this site? If so, please cite them.
  46. Bob Lacatena at 05:14 AM on 21 June 2011
    Linking Extreme Weather and Global Warming
    103, Camburn, Just to clarify, because I know you are quite capable of missing my point... I do not deny that the climate has changed in the past, by very, very small degrees if by "we" you mean during the last thousand years of civilization, or by larger degrees if by "we" you mean during the existence of homo sapiens as a species, or by even larger degrees if by "we" you mean "the denizens of the planet," spanning back to the earliest creepy crawlies that grew in the oceans. What is categorically false are the unspoken implications of your statement that climate change is either impossible to predict (or in this case prevent), or that it is harmless (given the countless mass extinctions and dead civilizations that have resulted from past climate change). So when I say that your statement is singularly false and overly simplistic, this is what I mean.
  47. It's not bad
    The IPSO report is out today here. Bad news: "the world's ocean is at high risk of entering a phase of extinction of marine species unprecedented in human history."
  48. Rob Honeycutt at 04:22 AM on 21 June 2011
    Linking Extreme Weather and Global Warming
    Camburn @ 103... We all know that climate has changed in the past. No one ever contradicts this. If climate had changed little in the past then there would be little chance that we could change it today. The central issue is how we are changing climate today. [Source] When I see this diagram of the CO2 record then I become very concerned about the stage we are setting for ourselves. I also think there is a fundamental misunderstanding that goes on with regards to extreme weather events. What we're looking at today is likely the result of adding just 4% more moisture to the climate system. It's looking pretty clear that even this small amount is resulting in changes in extreme weather events. Not yet outside the realm of what has likely been experienced in the past 10,000 years... but getting there. The question becomes, if this is what we get from 4%, what will we be seeing when we've added 40% more moisture to the climate system? It's my understanding that this is the problem we face. Is that extreme climate (extreme relative to today) something never on this planet? Probably not. But probably unseen for many many millions of years. Certainly unseen by any species existing today. Certainly unseen by human civilization.
  49. Bob Lacatena at 04:09 AM on 21 June 2011
    Linking Extreme Weather and Global Warming
    103, Camburn,
    We have always had climate change...
    This is a singularly false and overly simplistic statement, one which begs to ignore problems and science, rather than face them. Surely you have something more substantive and meaningful to offer the world than the modern equivalent of "if man had been meant to fly, God would have given him wings!"
  50. Eric the Red at 03:48 AM on 21 June 2011
    Infographic: 97 out of 100 climate experts think humans are causing global warming
    KR, I know that I have the reputation of being the "no problem guy" just because I do not hold many of the positions as being very solid. Just because I stick to the notion that all these scenarios are probably (not just possible), is no reason to think that I do not believe the science. I will not accept or dismiss premises based on one or two papers, especially when those papers are written by people whose sole purpose is to promote their hypotheses. When the data becomes convincing, then I will join in. I have a particularly disdain for models (some based on personal biases dealing with modelers in the past) that cannot be verified with data. Remember, there is a big difference between evidence in support of a theory, and evidence that confirms a theory. Currently, we have a a lot of evidence in support of AGW, however, many scientists are extrapolating well beyond the limits of the data, and scientists will tell you that is introduces a large amount of uncertainty.

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