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Comments 72951 to 73000:

  1. Pielke Sr. and SkS Warming Estimates
    Tom Curtis - The 0.2 Watts per meter squared is for the two indirect aerosol effects that are reported on in the 2005 NRC report. This is an estimate based on them being positive. There is clearly an uncertainty on their value but the report concluded they were positive. New research remains unclear on their magnitude.
  2. Pielke Sr. and SkS Disagreements and Open Questions
    Eric (skeptic) @51, the supposition that weather should be considered as a forcing rather than a feedback presumes that the weather does not respond sensitively to changes in global mean surface temperature. This is not true, for example, of the southern Sub Tropical Front (mentioned by you in 47). The Sub Tropical Front is at least partly driven by the presence of strong westerlies in the latitudes south of Australia and Africa. The location of those westerlies are known to be sensitive to global mean temperature, moving south as climate warms, and north as climate cools - behaviour mimicked by the STF. The sensitivity of the STF's location to temperature is also shown by the fact that its location varies with season. The same is also true of the location of the Jet Streams, whose position is primarily determined by the location of the boundaries between Hadley Cells, Ferrel cells and Polar Cells (see diagram below). Although there location is influenced by geographical barriers such as the Himalayas, the global circulation is their primary determinant, and that circulation is determined by the GMST. As temperatures rise, Hadley cell becomes large, pushing the jet streams further from the tropics. As it cools, the Hadley cell shrinks bringing the jet streams closer to the tropics. In both cases, because the "weather" effect is temperature sensitive, it is properly treated as a feedback. Treating these weather effects as feedbacks rather than as semi-permanent geographical features allows the issue to be stated this way: "Measuring temperature and forcing differences between glacial and interglacial will not determine current climate sensitivity because climate sensitivity varies greatly with different temperatures and geographical arrangement." So, stated, the claim is obviously open to empirical testing. As it happens, climate sensitivity has been tested across the range of phanerozoic distributions of continents and climate conditions and resulted in very similar values: While it is true that changes in ice albedo will have far less effect now than during the LGM, Hansen determined the climate sensitivity for green house gases independent of that for albedo, so that determination is not effected by that difference. Further, current conditions are more susceptible to the water vapour feedback than at the LGM.
    Response:

    [DB] Upgraded the image quality on Royer Figure 1.

  3. Pielke Sr. and SkS Warming Estimates
    Albatross - The values I present were given to show reasonable deductions from the IPCC value and that of Skeie 2011. I do not know the precise value (and neither does anyone) but the fraction is clearly well less than 50% using reasonable values. In terms of the statement "a simple scaling of the forcing with the CO2 doubling climate sensitivity parameter may not be appropriate". this applies to the entire question on the fraction of positive radiative forcing between 1750 and currently. Lets move on.
  4. Philippe Chantreau at 10:54 AM on 11 October 2011
    Pielke Sr. and SkS Warming Estimates
    SkS has done a pretty comprehensive overview of Dr Spencer's contribution. However, he also authored numerous other pieces, opinions or statements that are commonly used to justify skepticism. It is entirely wihin the scope of SkS' stated vocation to examine these other productions of his and see how they compare with the existing science, including his own. As far as I have read, that is what has been done on SkS. I would like to remind readers that the purpose of SkS is not to assess the state of the science and identify areas of greater or lower uncertainty, or recommend avenues for further research. Not that such questions should not be given attention here. Ideally, it would be possible to indeed focus only on true, interesting scientific problems. However, SkS was created in response to the tremendous effort of disinformation and propaganda that this particular area of science has unfortunately experienced. The purpose of SkS is to examine common claims put forth by self proclaimed skeptics who doubt all or part of well accepted conclusions reached by mainstream climate science. These claims are examined and weighed in regard to what the published science reveals to date on the subject. In that sense, all skeptic claims are fair game to SkS, whether they can be labeled as "policy/political statements" and regardless of their source.
  5. Understanding climate denial
    Elsa, Consensus is what is left when the data is clear. The consensus does not advance the science, the science advances to form the consensus. You provided smoking as an example of consensus in science, not me. I provided a climate denier that challenged your view expressed here. He is as wrong about smoking as he is about climate change. 3 seconds on Google yields "Thabo Mbeki invited several HIV/AIDS denialist" these people have credentials as strong as the AGW deniers you refer to. The proponents of dark matter say the challenge to gravity is too great to be considered, not a small adjustment see here for example. These are specific challenges to show that your examples of scientific consensus are not completely accepted as you claimed. The deniers of climate change are just louder and better financed than the other examples I cited. My point about models is that the data that supports AGW is overwhelming without any model data at all. If you look beyond the denier arguments about models you will see that is the case. The paleo data alone is enough to show we are in big trouble, not to mention rising sea levels, retreating ice, increasing drought (and floods), and record temperatures.
  6. Eric (skeptic) at 10:33 AM on 11 October 2011
    Pielke Sr. and SkS Disagreements and Open Questions
    Skywatcher, you said "Why and how this change [in atmospheric jets and ocean currents] causes a threefold increase in sensitivity (and not a decrease) has not been specified, and is presently speculation." Allow me to clarify one fact: weather can be forcing or feedback because the energy lost or gained at TOA can depend on weather. Ocean currents are not a factor at TOA, but do greatly influence weather. The weather causes the loss or gain of energy which amplifies the cooling or warming from the other long term forcings. Some weather changes can be considered forcings because the glacial weather conditions are different from interglacial with different energy losses (cloud albedo, meridional flow and energy transfer, water cycle, etc)
  7. Eric (skeptic) at 10:23 AM on 11 October 2011
    Pielke Sr. and SkS Disagreements and Open Questions
    Regarding the graphic #48, do you believe that the change in weather from interglacial to glacial has no forcing effect (i.e. weather is defined as feedback only)? A small (negligible) forcing effect)? Dr Pielke pointed out that the equatorward displacement of the polar jet would be one such weather change (a positive forcing for the interglacial transition as pointed out in the paper I linked in #47). The cloud albedo would be different as well (with likely fewer clouds overall). The static diagram also does not explain the hysteresis (the forcing is not sufficient, feedback is required).
  8. Pielke Sr. and SkS Warming Estimates
    Dr. Pielke: this is one reason I recommend you focus on science and not Roy's policy/political statements; I find that recommendation especially puzzling, as overwhelmingly, SkS focuses on Roy Spencer's claims on the science. Spencer Slip Ups Now perhaps you are asserting that statements such as "warming in recent decades is mostly due to a natural cycle in the climate system — not to an increase in atmospheric carbon dioxide from fossil fuel burning" are political in nature, in that they don't follow from any robust scientific analysis.
  9. Pielke Sr. and SkS Warming Estimates
    Tom @12, Dr. Pielke says "I calculate that CO2 is ~40% for the anthropogenic positive radiative forcing." First, that value is still significantly higher than the original (and erroneous) claim of 26.5% that he has made on his blog, here and elsewhere in public. Second, Skeie et al. (2011) supersedes Ramanathan and Carmichael (2008), and represents our current level of understanding. Science moves on. Third, from Ramanathan and Carmichael (2008): "The TOA BC forcing implies that BC has a surface warming effect of about 0.5 to 1 °C, where we have assumed a climate sensitivity of 2 to 4 ºC for a doubling of CO2. Because BC forcing results in a vertical redistribution of the solar forcing, a simple scaling of the forcing with the CO2 doubling climate sensitivity parameter may not be appropriate". So they concede that their method may not be appropriate, or does Dr. Pielke wish us to forget/neglect this important caveat from their paper which he chose to cite?
  10. Pielke Sr. and SkS Warming Estimates
    Dr. Pielke, if you had read SkS' posts, you would realize we have examined Dr. Spencer's scientific research quite extensively. However, this calculation is essentially based on two factors - transient climate sensitivity, and the CO2/net anthropogenic forcings. Internal variability does not factor into the calculation of how much warming these forcings have caused. I agree, the aerosol forcing in particular represents a significant uncertainty. That's why we have been very explicit that we're stictly looking at the best estimates of these forcings. However, the CO2 forcing is very well-known, and we provided a 90% confidence range on the transient climate sensitivity parameter. Surely you can thus at least agree that CO2 has caused a 0.64 to 1.28°C (with a best estimate of 0.79°C) warming of average global surface temperature over the past century?
  11. Understanding climate denial
    "I find that the more I look at the models the less I am impressed by them. " Exactly how are you looking at models? Studying the code? Comparing prediction to observations on the time scales of model skill? Or what?
  12. Pielke Sr. and SkS Warming Estimates
    Dr Pielke @4, where you say:
    "If we use the 0.9 Watts per meter squared value for the black carbon that you present,from the Ramanathan and Carmichael (2008) values and the 0.2 Watts per meter squared as reasonable estimates based on the NRC (2005) report, which is still an accurate summary of our limited knowledge of this forcing, I calculate that CO2 is ~40% for the anthropogenic positive radiative forcing. This accepts the values for ozone that are listed in your table."
    does the 0.2 W/m^2 refer to aerosol effects, of some other forcing?
  13. Pielke Sr. and SkS Disagreements and Open Questions
    Eric and Dr Pielke, you're arguing there is a large increase in climate sensitivity as you go from interglacial to glacial conditions. The only suggested mechanism is that the large continental ice sheets, with their ~100m worth of sea level locked up inside them, divert atmospheric pressure systems and oceanic currents due to the change in terrestrial and marine topography. Why and how this change causes a threefold increase in sensitivity (and not a decrease) has not been specified, and is presently speculation. The trouble is, how do you get there from an interglacial world in which there is low climate sensitivity? The interglacial world has not got the large mid-latitude ice sheets, or the lowered sea level to alter ocean currents, and the orbital forcing is too small to initiate glaciation if your climate sensitivity value is low. You need the high climate sensitivity to turn a low insolation around 65N into ice sheets via increased snowcover and drawdown of CO2. Without the high climate sensitivity, the forcing is insufficient and the ice sheets do not form in the first place, and the oceans remain full of water. Do you see the circularity?
  14. Pielke Sr. and SkS Disagreements and Open Questions
    Dana @48, You beat me to it. And here is another reminder from another scientist, this time from Dr. Marci Robinson (US Geological Survey): "Yes, uniformitarianism is often defined to mean that the present is the key to the past. But we might be wise to remember another accurate description: The past is a key to understanding the future". Oddly, many "skeptical" scientists continue to ignore or dismiss the paleo record (the past) and seem to have no interest in learning anything from it, unless perhaps it appears to support a low climate sensitivity.
  15. Pielke Sr. and SkS Warming Estimates
    dana1981 - We know too little about the role of natural variations in the radiative forcing in the last century to know with such precision how much of that warming is from anthropogenic effects. This is based, in part, on the research and comments of Roy Spencer, Judy Curry, Judith Lean and others. [this is one reason I recommend you focus on science and not Roy's policy/political statements; he has added important new insight into the role of natural forcings including solar and internal multi-year variability]. Even with the anthropogenic forcings, we do not know what the actual aerosol and land use/land cover changes have contributed, relative to the radiative effect of added CO2, with respect to the observed surface temperature trends. There is also the issue of siting quality for the land portion of the surface temperature data. I agree that human's have significantly affected the annual average surface temperature trends, but, in my view, the issue as you present above inadequately considers all of the issues. Thus, I suggest we move on. I do not find this an important issue, but would be open to you explaining why it is. It seems to me that knowing the current forcings is much more relevant. P.S. I would like you to tell us if the water vapor/CO2 overlap was considered in your calculation. I do not see any problem in your calculation, if your numbers are used. We disagree with the values, however, as I wrote in my response.
  16. Book review: The Inquisition of Climate Science
    No money buys you an echo chamber where you hear what you want to hear. Yes, many in the fossil fuel industries are trying to cause consusion over climate change. But first they are confusing themselves. And it is not just profits. It is their sense of vocation, their belief that they are doing something beneficial to their societies that is threatened.
  17. Pielke Sr. and SkS Disagreements and Open Questions
    A reminder from Hansen and Sato 2011:
  18. Book review: The Inquisition of Climate Science
    DSL#53: "Gilligan's Island is a powerful commentary" Recall that GI included 'The Professor' among the castaways and the others did not blame him for their misfortune. A more modern version of this would have him 'voted off the island.' But the common theme to the bullet points in this post is not fear of technology, it is money talks.
  19. Understanding climate denial
    elsa, what is a "warmist" and who do you believe are the "warmists" who have "commented here" ?
  20. Understanding climate denial
    Michael Sweet: you say Dr. Lindzen says there is no link between smoking and cancer. I have not seen his views on this but I would have some sympathy. There is no causal explanation established (contrary actually to the CO2 warming theory where there is) between smoking and lung cancer although there is a high degree of correlation within one country between the two (it falls down when you try it across many countries I believe). You say past Presidents of South Africa denied that HIV caused AIDS. Actually I think it is one and I am not aware that he has any scientific credentials. No scientist has ever suggested this. You also say "Gravity theory has been challenged in the last few decades." I think the theory has been challenged by refinements to the basic theory, which is what happens if science is to advance. You say "All science advances by consensus." I could not disagree more and luckily I see I am not alone in this view in this blog, there are plenty of warmists who have commented here who understand that science advances from testing competing points of view, not consensus. If you need more help in this area I would be happy to explain it to you in more detail. Next you say "How much of this site is dedicated to modeling? Learn more about the data that supports climate science and you will lament models less." I find that the more I look at the models the less I am impressed by them.
  21. Greenland ice loss continues to accelerate
    @Lou: the graph's caption clearly states that it is based off of the average ice mass over the period 2002-2011. And yes I think you are correct regarding the expectation of cyclical patterns. It would also be incorrect to linearly connect the dots if they were not all based off of the same baseline.
  22. Eric (skeptic) at 08:46 AM on 11 October 2011
    Pielke Sr. and SkS Disagreements and Open Questions
    The glacial to interglacial temperature change is around 10C for a 50% increase in CO2, so the primary cause of the change s the ice albedo feedbacks as Tom pointed out above. So indeed it is true that "ice sheets formed due to the presence of ice sheets" and likewise melt due to the melting of ice sheets. Of course geography matters but mostly to the minimum and maximum states. One of the largest changes apart from ice albedo is weather. Here is one example: http://cci.siteturbine.com/uploaded_files/climatechange.umaine.edu/files/dentonTerminationsSci10-1.pdf: "Southward movement of the STF was a contributing factor for the large amplitude and rapid rise of temperatures during HS1 and the YDS within the region between 35°S and 45°S" which then caused glacier retreat. There is no way to tease out a 3C per doubling CO2 from a 10C per 50% rise in CO2 without a model and parameterized (i.e. not modeled) weather.
  23. Book review: The Inquisition of Climate Science
    Reading your comments, both from the US and Australia, maybe my over-simplistic idea of the prevailing self-interest value is just part of the picture. Indeed, you showed that in many instances it did not prevail. This is not unique to the US, though, be sure that it applies to single european countries and to the whole European Union as well. Yet, at least when dealing with global problems the balance seems to be shifted more on the global interest side. Americans, and australians as Stevo suggests, seem to be more torn apart between the two opposites as if they can't find their preferred balance. We may add that the crisis started a couple of decades ago, when the USA political and economic leadrship started to decline and which, like any crisis, tend to make people or nations try protect themselves from the outside world. This translates, as muoncounter says, in not being able to take the necessary steps. I'm trying to understand how come that a great nation decide to turn its back to the world and steadly point backward. We know from history that great civilizations may and do collapse; if a society denies the very existence of a problem it won't be able to solve it for sure. I am optimistic, though. I belive that the american people are able to show a strong will once they face the unavoidable conclusion. In some sense, the climate Pearl Harbour didn't arrive yet and this is what we're here for, avoid another (worse) Pearl Harbour.
  24. Book review: The Inquisition of Climate Science
    Agreed, dhogaza--on both comments--though I'd add that for me it was the idea of unions-as-progressive that was deflating. One more note for muon: let's not forget the contradiction in the social response to technology in the last sixty years. There was a great deal of fear of technology and science, expressed in thousands of SF movies and novels. I've always thought that Gilligan's Island is a powerful commentary on the response to the modern world. Anyway . . .
  25. Greenland ice loss continues to accelerate
    Every time SkS runs an update of this graph I have a hard time wrapping my brain around exactly what it says. So, I'm going to assume I'm not the only one staring at his or her monitor with a deeply furrowed brow, and ask if it means what I think it means... The data point for July 2011 looks to be almost exactly -1,100 GT. This means that it's 1,100 GT below the average of the July observations for 2002 through 2011, inclusive. Or does it mean that the July 2011 observation was -1,100 GT below the average of all 115 monthly observations (Jan 2002 through July 2011, inclusive)? Or is it something else entirely? Given the cyclic nature of the data, I think it's the second version, comparing each month to the average for the whole data set. In any case it means Greenland is losing a terrifying amount of ice.
  26. Understanding climate denial
    182, Jonathon,
    The odd thing about AGW, is that this is the first time I can remember people arguing about a scientific consensus, and whether or not one exists.
    Exactly my point. It rarely happens. It happened in a less precise way with tobacco and cancer. And CFCs and the ozone hole. But in those cases it was a lot more of "we don't know" than "there is no consensus." So why do you think there is this consensus argument now? If you go to look at all of the literature (search around scholar.google.com) and get a really good feel for what's going on in the field, versus what is pumped up in neon and sparklers in the blogosphere... what do you think? Forget studies, and surveys, and everything else. Just by glancing at scientific papers and seeing how most climate scientists talk to each other... is there a consensus? This isn't the thread to answer that question, but when you do get an answer, then you can ask yourself again about why this is the first time this question of "consensus" is arising, and the answer is a single word. I'll give you a hint. It begins with the letter "d."
  27. Understanding climate denial
    Good point, muon. Consensus of opinion is important, though, because it can change the direction of scientific activity in a world of limited resources. The interface with the democracy is, after all, where the real battle is being fought right now, and that is the realm of the consensus of opinion, for better or worse. The same people who publicly tout Dr. Pielke as an example of non-consensus do so in order to sway public opinion against the position that something needs to be done--ironically, a position that Pielke has repeatedly endorsed. DM: Too many people use Kuhn to support the idea that progress is an illusion: paradigms will always be shifted--science changes like fashion. One interesting study into the idea of consensus is performed indirectly by Charles Mann in his 1491 (haven't seen 1493 yet).
  28. Book review: The Inquisition of Climate Science
    Dave123#36: "in the US we believe deeply that one person's opinion is as good as another's. And it's all opinion you know. The resentment of there being people who actually know more or are smarter runs deep" That's a relatively recent development. Not all that long ago, the US believed in science and technology; we valued expertise, not opinion. We could build large-scale projects: we went to the moon based on the work of experts. Now we value opinion; anybody who 'can't see climate change in his own backyard' has an equal say in the 'debate.' Coincidentally, we have a country that can't get much of anything done. Is it any wonder we can't deal with complex issues? Is it any wonder we deny climate science and investigate scientists? We have an education system that ranks slightly behind Estonia. But who needs a good education when only opinion matters.
  29. Understanding climate denial
    DikranM#181: This 'consensus is bad' argument is the ultimate strawman. Would those who challenge the value of consensus be satisfied if more climate scientists disagreed about the causes of climate change? The 'skeptic' who raises this herring is hoping that the subsequent discussion will forget that it is the consensus of the evidence, not the consensus of opinion that counts.
  30. Understanding climate denial
    Scientific advancement can occur through individuals or groups of individuals (my post was not intented to mean one person working in a vacuum), and can occur through filling in small gaps of knowledge or through major breakthroughs. In eash case, the current mainstream view changes vased on the new work, as Dikran explained previously. Some changes can be imperceptively small, others can have dramatic effects. I have to agree with Sphaerica that nobody wakes up one day and says we have a consensus. Oftentimes, a consensus is never reached as differing theories keep moving in different directions (a classic example of this is the theoris of dinosaur extinction). The odd thing about AGW, is that this is the first time I can remember people arguing about a scientific consensus, and whether or not one exists.
  31. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee#140: "It appears that this blog is not about discussion to discover the truth but rather about promoting a dogma. ... you have shown that this is a religion and you are defending the faith. " What utter unsubstantiated nonsense. On this thread and on the parallel thread Cosmic rays: backing the wrong horse, knowledgeable people met your misconceptions with arguments backed by scientific literature; example here, to which you made no reply. And rather than admitting the factual errors in 'its the sun,' as shown here, you concoct a 'correlation is causation' argument that the well-known Arctic amplification is due to polar magnetic fields. There is nothing 'faith based' in this discussion, except your complete adherence to the doctrine of 'anything but CO2'. Now that's disappointing.
  32. Book review: The Inquisition of Climate Science
    But we're getting way OT here and should probably wind this down ...
  33. Book review: The Inquisition of Climate Science
    DSL: "All of this is shorthand, though. History is far more overwhelming than science." Oh, yes, after all it's the combined experience of billions of people over thousands of years ... I've just been tossing out some ideas for Riccardo to think about given some of his notions about the American people, and it's great to see others like you and dave123 add your thoughts. I wouldn't lay the weakening of unions entirely on globalization, not here in the US. Remember that anti-union Reagan had a lot of support among union rank and file workers. Reagan's conservative positions on social issues apparently resonated among such workers even though any rational evaluation would make it clear that voting for Reagan was voting against the economic self-interest of union workers. Globalization over the last couple of decades certainly had an overwhelmingly important role in weakening unions, though. Not only globalization, the rise of the "right to work" movement has allowed Boeing to retaliate against its unionized workforce in Washington by building a new 787 factory to be populated with lower-paid, non-union workers in the SE ...
  34. Book review: The Inquisition of Climate Science
    critical mass, I'd say a critical reading of that thread, in particular gavin's inline responses to RPSr, mostly demonstrate that RPSr doesn't really know what he's talking about when he blows smoke about heat transport in the ocean. But that's for over there, not over here, where it's OT.
  35. Pielke Sr. and SkS Warming Estimates
    Yes, Tom Curtis provided valuable contributions to this post. Dr. Pielke, the question we are addressing with this post is the CO2 (and net anthropogenic) contribution to the observed surface warming over the past century. In order to answer this question, we must examine the change in forcings over that period of time (not the remaining imbalance/unrealized warming, which is a separate issue). You have not identified any problems with our calculations of the CO2 contribution over the past century - namely accounting for your calculational errors and correcting values for the methane, ozone, and albedo forcings brings the CO2 contribution to the net positive radiative forcing over this period to ~50%. We also showed that CO2 caused ~0.79°C, and the net anthropogenic forcing caused ~0.65°C surface warming over the past century. We again ask if you now agree with these values (and the ranges for these values listed in the post above). The issues you raise regarding the CO2 contribution to the more recent radiative imbalance is a separate question, which does not affect the calculation of the total CO2 contribution over the past century. We can proceed to discuss this issue as well, but first would like to close the discussion on the human-caused warming over the past century.
  36. Pielke Sr. and SkS Disagreements and Open Questions
    Dr. Pielke, the large ice sheets during the last glacial maximum formed as a consequence of the low global temperature. Attributing the temperature decrease to the presence of ice sheets and their geographical impact is circular logic. You are effectively arguing that the ice sheets formed due to the presence of the ice sheets. A climate sensitivity of ~3°C for doubled CO2 is a robust feature of the Phanerozoic Eon, across a very large range of continental distributions. Are you suggesting that changes in geographical distribution have mimicked the effect of a high climate sensitivity across all those distinct geographical distributions and time?
  37. Dikran Marsupial at 05:32 AM on 11 October 2011
    Understanding climate denial
    elsa As Sphaerica suggests, nobody has said that consensus advances science, it is the other way round, the consensus is the result of advances in the science reducing the key uncertainties to the point that (more or less) everybody is in agreement on the basics. Perhaps you should read "The Structure of Scientific Revolutions" by Thomas Kuhn. He basically argues that science proceeds via a sequence of paradigms, each of which represents the current mainstream view of the science of the day, which persists until the flaws in the current paradigm become overwhelming and there is a scientific revolution leading to a new (hopefully improved) paradigm. So according to at least one well known philosopher of science, the existence of a consensus is what you would expect to see once a paradigm has been established (i.e. the science is essentially settled - at least for the moment ;o). I'm not personally much of a fan of Kuhn, IMHO all scientific progress shifts mainstream view if only imperceptably and it is hard to define what size of shift is categorised as a paradigm shift and what isn't. However the point remains that the existence of a consensus is evidence of a stable paradigm (i.e. a mainstream view of the science that is essentially robust in which a fatal flaw has yet to be revealed. Skeptics often think they have driven the final nail into the coffin of AGW, but unfortunately they have usually just bashed their thumb).
  38. Understanding climate denial
    173, elsa,
    Scientific "consensus" is an odd way of advancing science.
    A strawman. No one ever said that consensus advances science. The point is that the scientists working actively in the field have reached a point where they all pretty much agree on what they understand and what it means. That happened simply because they all started to individually come to the same conclusions. They didn't get together and take a vote, or debate on a group position, or adopt it as a strategy. That's just what happens. After a while everyone starts to say "wait a minute, this is all starting to fit." That's called a consensus. The problem is that no one's ever before had to prove to legions of deniers that such a consensus does or does not exist. No one every really even thinks about it and says "aha, I think we have a consensus!" No, normally science just works. What you have now, however, are legions of deniers who don't know what they're talking about, don't want to either understand or accept the science, and who attempt to circumvent the science by manufacturing the illusion of doubt, and part of that illusion is to claim that there are a lot of reputable scientists who disagree with current climate science. There are only a handful, because there is in fact a consensus, which is the tangential result of everyone having done so much research that most of the pieces fit, and very few people question how they fit or what they mean.
  39. Understanding climate denial
    Jonathan, that's an odd view. Most scientific work (advancement) is not "breaking through." Most scientific work is recognizing gaps in previous work (existing understanding) and working to fill those gaps. Most scientists do not go to work each day hoping to overturn the fundamentals of their disciplines. The scientific understanding of the world has become more and more precise over the last 200 years. That is true largely because scientists have been able to build carefully and methodically on the work of their predecessors rather than constantly re-writing the fundamentals. And it is not "individual" scientists doing this. Science is highly social, and major breakthroughs (not breaking through perceived boundaries but finally having the means to fill in a tough gap) occur through the work of often dozens of scientists. I can't remember the last time I saw a major study in the hard sciences authored by one individual. Your perceived moments of the individual Galileo are extremely rare. Most major changes to the fundamentals occur through individuals who work within schools of thought, schools that have developed for years with a core group of scientists. Finally, one can scarcely move a few centimeters through the history of science without tripping over failed schools of thought.
  40. Understanding climate denial
    173, elsa,
    ...they have the trappings of science but are in fact not scientific at all.
    Spoken clearly and unequivocally by someone who clearly does not understand the science well enough, or else you would not make such an outrageously false statement. I suggest you begin with Dr. Spencer Weart's The Discovery of Global Warming. When you have studied enough to understand what we do in fact know, how, and how well, then you can come back and correct your own mistaken post.
  41. Understanding climate denial
    This looks like semantics and/or sophistry to me. Yes, science is advanced by research... but scientific advancements are recognized by consensus. Mendel did the research to advance science with the understanding of genetics... but nobody noticed until decades after he had died. Further research on genetics was stalled until the work was rediscovered and a consensus grew that it was correct and useful information.
  42. Pielke Sr. and SkS Warming Estimates
    I just want to recognize the important contribution made by Tom Curtis in preparing the above post.
  43. Pielke Sr. and SkS Warming Estimates
    KR - I agree this scaling would be the same if all of the forcings had the same time evolution. When I discussed this with V. Ramanathan and others on our committee, however, the conclusion was that the other forcings ramped up more recently. In any case, what we really need is the current best extimate of the 2011 global-annual averaged radiative forcing and the best estimate of the 2011 global-annual averaged radiative imbalance. The difference between these two values is the global-annual averaged radiative feedback.
  44. Pielke Sr. and SkS Warming Estimates
    KR- My question remains, what is the current radiative forcing of CO2? In the SPM for the IPCC 2007 report, with respect to their presentation of the values in their figure SPM.2 they write "Global average radiative forcing (RF) estimates and ranges in 2005 for anthropogenic carbon dioxide (CO2 ), methane (CH4 ), nitrous oxide (N2O) and other important agents and mechanisms, together with the typical geographical extent (spatial scale) of the forcing and the assessed level of scientifi c understanding (LOSU)." They specifically state "Global average radiative forcing (RF) estimates and ranges in 2005". Then in footnote #2, they write "In this report, radiative forcing values are for 2005 relative to pre-industrial conditions defined at 1750 and are expressed in watts per square metre (W m–2). " At the best, this was sloppy writing (as it is corrected/clarified in the footnote), but the figure caption itself is misunderstood by quite a few people. At worst, the writers were not clear oo this when they wrote the figure caption. In any case, what would SPM.2 look like for the current forcings?
  45. Pielke Sr. and SkS Warming Estimates
    Dr. Pielke - Minor addition to my previous comment: If you are looking at unrealized warming and remaining imbalances (rather than the changes since 1750 that are the topic of this thread), it's noteworthy that you cannot just scale the change in CO2 contribution - all radiative imbalances scaled by unrealized warming would be scaled as well, meaning that the relative contribution of CO2 should not change. Your 20% reduction of relative CO2 contribution is, again, not justified in my view.
  46. Understanding climate denial
    Michael. I disagree. Science does not advance by consensus. Consensus (if it occurs) is one of the last steps in advancing science, and only occurs after much scientific work has been performed. Science advances by individual scientists breaking through previously perceived boundaries to make new discoveries. Oftentimes, these scientists are ridiculed by their peers for proposing such "ridiculous" theories. These theories go against the established scientific tenets (consensus), and require sufficient proof to convince the scientific establishment. Look at history, how many scientific theories were advanced by consensus? Consensus is for bureaucrats and politicans. Science advances by research and evidence. I side with Elsa on this one.
  47. Pielke Sr. and SkS Warming Estimates
    Dr. Pielke - "You also did not discuss that CO2 has been increasing for over a century and some of the CO2 radiative forcing during that period would have been accomodated by the warmer climate. As I wrote, in 2005 V. Ramanthan replied to me (in an estimate) that about 20% of the difference between pre-industrial and current radiative forcing would have been accomodated. Thus the current radiative forcing from added CO2 would need to be reduced by this amount." I would have to strongly disagree - the radiative forcings discussed here (as in the IPCC AR4, the basis of this discussion) are relative to 1750 pre-industrial forcings, not the current imbalance (unrealized warming) between temperatures and those forcings. The 20% adjustment you recommend here is an odd (and IMO quite unwarranted) redefinition of well understood terms - shifting the baseline. Unrealized warming and current imbalance are different terms, different values, than forcing changes since 1750.
  48. Understanding climate denial
    Elsa, climate modeling is an attempt to forecast climate based on a sound physical model and probable conditions. It is the equivalent of Doll saying, "Smoking will continue to cause premature deaths in smokers at a rate of 75 per 100 over the next 100 years." His work was not predictive, or, if it became predictive, it would have the same basic weakness of all models of real world phenomena: the unknown. Yet science is pointless without such predictive applications (as Doll notes through the act of quitting smoking). Climate, as you say, is extraordinarily complex, and it must include the human element, so it becomes even more complex. Does that necessarily mean that it should not be done or that it is currently being done poorly? No. Many of the models are actually quite good. Note that you offer a range of between 0C and 4C, but you do not give the model confidence for any values in this range. This suggests you haven't studied climate modeling. Yet you make absolute statements about the activity. If you have questions, ask them. Further comments on modeling should be posted to the appropriate threads. Use the search function for "models" -- there are quite a few threads on the subject. Oh, and there has been a great deal of work done recently on causes of genetic mutation in smokers. See this study in Nature.
  49. Pielke Sr. and SkS Disagreements and Open Questions
    CBDunkerson - I am proposing that now that we have good ocean heat data coverage, we move towards replacing the global annual average surface temperature trend as the primary metric to diagnose global warming. Certainly 7 years is not sufficient but will be as the years pass. Since the models predict (project) how this ocean heat should change, we can track their skill and set up requirements for them to be considered skillful with this metric.
  50. Understanding climate denial
    Elsa: Ask Dr. Lindzen (the well known climate denier) about the link between smoking and cancer: he claims there is no data to support it. One of the past Presidents of South Africa denied that HIV caused AIDS. Gravity theory has been challenged in the last few decades (check alternative gravity versus dark matter theories). If you do not pay attention to scientific developments you are not aware of what is current. All science advances by consensus. If you learn more about science you will realize that is the way science works. How much of this site is dedicated to modeling? Learn more about the data that supports climate science and you will lament models less.

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