Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings

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.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  1449  1450  1451  1452  1453  1454  1455  1456  1457  1458  1459  1460  1461  1462  1463  1464  Next

Comments 72801 to 72850:

  1. Australia’s contribution matters: why we can’t ignore our climate responsibilities
    Just for the record,the "Carbon Tax" bill was passed today through Australia's federal House of Representatives. With no chance of the legislation being blocked in the senate, we'll have a carbon trading scheme in place on July 1 2012. Despite claims by the leader of the opposition to repeal the legislation should he win government at the next election in 2013, he will not have the numbers in the senate to make good such a promise. The long and the short of it is, Australia has at least 4 years to get accustomed to, and to refine, a carbon trading scheme.
  2. Greenland ice loss continues to accelerate
    In my rush to comment, I made a mistake at 24. Hansen and Sato predict doubling of GIS ice loss per decade which, by 2050 would result in cumulative loss of 48,000 gigatonnes with annual loss increasing to 3,200 gigatonnes per annum. Tom Curtis - I think that is right, mildly beneficial until the last 20 years of this century when RSL as much as ice loss seems likely to cause problems. Though I hear from Greenlanders in the far north west that they are already being caused problems by lack of sea ice inhibiting travel and hunting.
  3. Sea level fell in 2010
    Thanks Papy, demonstrates the relationship nicely.
  4. Greenland ice loss continues to accelerate
    Thanks Mauri.
  5. Pielke Sr. and SkS Warming Estimates
    "and the fact that CO2 is not even the large majority of the positive radiative forcings underscores this need. " But CO2 _is_ the single largest contributor. Moreover, emissions of CO2 lead to changes in atmospheric concentrations that can last 100s or 1000s of years... many of the other forcings are much more transient (eg, CH4, O3, BC, contrails, etc.). So, while I agree that these other forcings are important, and we certainly shouldn't ignore them, CO2 is clearly, at the global scale, the primary contributor to long-term climate change. If, in the next half century, human society realizes that global climate change is a problem, it will be possible at that point to reduce CH4, BC, and O3 concentrations fairly quickly. All the CO2 we've emitted between now and then, though, will be pretty much permanently in the carbon cycle until we figure out air capture... I'm also unconvinced that the IPCC hasn't adequately addressed most of these other contributors. I'd certainly admit that the IPCC could do a better job on the causes of weather events, but that is a hard problem, and they are building up to it (In my opinion, interesting recent papers have included interactions of large scale weather with sea ice retreat, solar fluctuations, and historical attribution of southwestern megadroughts to ocean cycles and other factors). But they _do_ make their best attempt at characterizing global forcing from as many sources as possible, and between AR4 and AR5 are probably putting a lot of effort into getting better numbers for the most uncertain of these (such as BC and other aerosols).
  6. SkS Weekly Digest #19
    Bern & panzerboy: There is a technical glitch embedded in the toon, but I do not know how to fix it. Perhaps one of my tech savy colleagues will be able to do so. I use Internet Explorer and I do not see a toon on either the home page or on this version.
    Moderator Response: [DB] It's there in Firefox 7 but not in IE 8.
  7. It's cooling
    NETDR - right. And if climate science turns about to be correct (ie it keeps warming as predicted), will you graciously return here to agree and then move on to work for GHG reduction? Or it will it be try to find another excuse for inaction?
  8. Pielke Sr. and SkS Warming Estimates
    Rob Honeycutt - You wrote that people will say it's only 28% of the forcing" so they will translate "Dr Pielke says we don't need to worry about CO2." I do not know how many times I can state it, but I certainly agree that added CO2 is a first order climate forcing (with the biogeochemiccal effect being the larger issue, in my view), and have said so repeatedly in my weblog posts and in my papers. I support my son's approach, as presented in his book "The Climate Fix" as the way forward to promote limiting the increase. However, all of the first order climate forcings are important (the global average negative radiative forcings, the regional heterogeneous radiative forcings, and the "non-radiative" climate forcings). In my view, the IPCC has failed to adequately consider these other human climate forcings and the fact that CO2 is not even the large majority of the positive radiative forcings underscores this need. Most, if not all, of these other climate forcings will persist at some level for the foreseeable future and, in terms of how they affect atmospheric circulations, could be much more important than the effects on weather patterns from the radiative effect of added CO2. This is the perspective that we presented in the 2009 EOS article and in the 2005 NRC report. The precise fractional value with respect to preindustrial and 2011, however, is not an important issue. In the biogeochemical perspective, it is the atmospheric concentration that matters, and it is continuing to increase.
  9. Models are unreliable
    It also looks like your friend is confusing physical models (used by climate scientists) with statistical models. However, for a purely phenomenological approach, then perhaps he should look at Benestad and Schmidt
  10. Understanding climate denial
    well said Composer99 - we have an example of word games with Jonathon here. I was refuting his suggestion (in #214) that a large range of values does not equal consensus, Jonathon comes back (in #226) with "ah, but it might not be catastrophic", reframing the question and trying to divert attention from the incorrectness of his original fallacy. Jonathon, whether or not it's catastrophic is irrelevant in this context. The point is that, either when heading towards the cliff face, or being on whatever floor in a burning building, there would be a clear consensus that bad things will happen if no action is taken. Consensus can exist with a large range of possible outcome values, you were disputing that in #214. I showed your dispute to be wrong, so you changed the subject. Another view into the world of denial? A couple of decades ago we were on the ground floor with an easy exit, now we are well on the way to the second floor, heading up. Nearly everyone's saying the building's on fire. Do you believe the one crank saying all the smoke is an illusion?
  11. Understanding climate denial
    Jonathon - "If you were trapped in a burning building and had to jump, would it matter if you were on the 1st of 5th floor?" To quote Herman Daly: "But as long as we focus on measuring these inherently uncertain empirical consequences, rather than on the certain first principles that cause them, we will overwhelm the consensus to “do something now” with ditherings about what we might someday consider doing if ever the evidence is sufficiently compelling. I am afraid that once the evidence is really compelling then our response will also be compelled, and policy choice will be irrelevant. To make the point more simply, if you jump out of an airplane you need a crude parachute more than an accurate altimeter." (emphasis added) If, given the vast quantities of evidence available, you feel that we are not 'falling' at some rate, not suffering a changing climate with consequences to ourselves due to our actions, then you are in denial. Which is the topic of the original post of this thread.
  12. Understanding climate denial
    Mark Chu-Caroll over at Good Math/Bad Math often points out that the worst kind of math is no math at all: a lot of math/physics cranks play language games when attempting to advance their position or refute whatever mainstream position opposes theirs and then fail to back their claims up with actual calculations, data, or other evidence. I suggest that a lot of climate science denialists are engaged in the same behaviour: playing language games, semantics games, quoting Popper without regard to context or other aspects of scientific thought, and then failing to back it up with actual science. The big difference is that your garden-variety math/physics crank has a lot less company.
  13. Understanding climate denial
    Skywatcher, If you were trapped in a burning building and had to jump, would it matter if you were on the 1st of 5th floor? I think it might. Just because you are not on the ground floor with an easy egress, does not mean that the outcome will be catastrophic.
  14. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    skywatcher @ 208 Thanks for the link to the Peterson Paper. I am reading it now.
  15. Understanding climate denial
    223, Lloyd, Well said, and far more concise than my rambling. Well done.
  16. Understanding climate denial
    elsa,
    ...it is impossible to prove a theory as right.
    Yes, everyone here knows that very well. It is by itself a meaningless statement. Obviously there are lots of things that science "knows" well enough. You're playing games with words and concepts.
    What I would deny is that we know what it is or can test the hypothesis in any meaningful way.
    Then you have not looked at the breadth and depth of knowledge, understanding and measurements that underpin the science. It is quite vast, and any number of observations support it. None refute it. Your position here is thin, and based only on your own ignorance of the science. You presume a lot, trumpet how silly and wrong everyone else is, and you are wrong in doing so.
    We are not given a link by physics we simply do not know the relationship and if you disagree with that tell us what it is.
    Actually, our understanding of the physics is so strong that you would need to completely revolutionize several main aspects of science for it to be wrong. You'd have to explain how warming could not occur. The physics says that things have to warm, and anything else requires that we very much revise our understanding of basic physics. As far as actually teaching you the physics, in detail, you have a whole lot of learning to do. Ten thousand comments here would not cover it. But I have already directed you to a start, something that I don't think you have begun to look at (given your attitude), and that is to go read Spencer Weart's The Discovery of Global Warming.
    In addition I would say that what you call denialism survives because the warmist view is so often apocalyptic
    I love this sort of argument. You don't like how serious the implications are, so therefore it's not true and not believable.
    ...there are other factors that move sea level apart from temperature
    Of course there are. And we understand a lot of them, and are learning more every day. But there are no major hidden factors that have not been taken into account. It's not magic. See, this is the big problem with your entire post. You put a lot of time into telling everyone else what we don't know, when you have no grasp of what we actually do know. You have already demonstrated that your understanding of the models is wildly inaccurate. You demonstrate here that your understanding of the physics is abysmally thin. Your understanding of the observations and how they relate is equally thin. Elsa, you are lecturing people who understand all of these things. You are defiantly and adamantly telling us what you think you know, which is close to nothing. To you, the science is magic, and so you argue as if you were arguing against magic. Please stop. Please educate yourself. Read Spencer Weart's writings. Start to learn the actual physics. Look through the wealth of information on this site. Stop posting from a position of arrogant and dismissive ignorance, and instead learn what it is that you are completely missing. One last note. Using the term "warmist" makes you look silly and uneducated. I suggest you drop the term. Unlike deniers, I really don't care if you do. You can use silly labels all you want. It says a lot more about you than it does about me.
  17. It's cooling
    Netdr#173: "we are at the start of a 20 to 30 year cooling cycle." Yet just here, you posited that it has failed to warm since 2001. So we are ... 10 years into your 20-30 year cooling? And we just had the hottest year on record. Funny kind of cooling, that.
  18. Understanding climate denial
    Elsa, You have left out other characteristics of scientific theorys, especially parsimony and explanatory power. Occam's Razor is the rule of thumb that has scientists seeking theorys that are no more complicated than is necessary to explain phenomena. You do not introduce new entities or processes to explain phenomena if known entities and processes are sufficient. For example unspecified 'natural cycles' is a non explanation. What natural cycles precisely? If you look at known natural forcings that could potentially cause temperature changes you find that they could not have cause the observed temperature changes over the past fifty years. If you look at greenhouse gas changes you find that they could have. Now there might be unknown natural forces that caused the changes but why appeal to unknowns when knowns will do? And being unknown of course they are untestable. And there is explanatory power. A high greenhouse gas sensitivity explains a lot of phenomena about current and past climate. A low sensitivity struggles to explain near as much. That is part of what I and others were referring to when we talked about consilience.
  19. Greenland ice loss continues to accelerate
    Agnostic @24, exactly! At current rates of melt the Greenland ice melt is merely interesting, and mildly beneficial to inhabitants of Greenland (who gain more arable land). If the acceleration continues it will become a major cause for concern, though not, I think, catastrophic at any realizable level of ice melt.
  20. Greenland ice loss continues to accelerate
    It seems to me that acceleration in the rate of ice loss from the GIS is doing no more than what Hansen and Sato 2011 predicted - doubling per decade. Trouble is, if it continues doing so, by 2050 the rate of loss will be in the order of 48,000 gigtonnes per annum. Then we shall have something to worry about!
  21. Book review: The Inquisition of Climate Science
    DSL#48: "another look into the minds of US conservatives," Here's yet another revealing look, highlighting some key traits: denial of scientific evidence, use of government to censor science. Rice professor accepts Gulf article's fate
    A Rice University oceanographer said he accepts a decision by the state's environmental agency to kill an article he wrote on sea-level rise in Galveston Bay, ending a standoff over the article's references to rising sea levels and human-caused environmental change. "I'm willing to live with not having it published," John Anderson said Tuesday. "I refuse to have it published with their deletions."

    TCEQ is Texas' environmental quality agency; from their mission statement: "Our goal is clean air, clean water, and the safe management of waste." The agency's director, Texas A&M Biological and Agricultural Engineering Professor Bryan Shaw, was appointed in 2007 by Gov. (and current presidential hopeful) Rick Perry. Dr. Shaw is on record as disagreeing with the unanimous opinions of the TAMU Atmospheric Sciences department (Andy Dessler, John N-G, et al) and supports his Governor's opinions on climate change. Inquisition? Nah, just censorship. But you will recall that the Church banned Copernicus' book before putting Galileo on trial.

  22. Joseph E. Postma and the Greenhouse Effect
    John Nicol @14: 1) Postma made a clear error in the maths, as pointed out by Chris Colose:
    "Postma actually doesn’t get the atmospheric radiative flux right. The emission is not σTa4, it is fσTa4, where f is the atmospheric emissivity/absorptivity (following his notation). The emissivity is a unitless factor between 0 and 1 descrbing how good of an absorber/emitter the object is relative to an ideal body. f = 1 describes a blackbody. By Kirchoff's law, the absorptivity of a layer must be equal to the emissivity (at the same wavelength)[.]"
    You cover for this by saying that the "emissivity and absorptivity are taken to be 1". First, that is not correct, for if the absorptivity was taken to be one there would be no need for a term for the transmitted surface radiation. Second, an emissivity of one is thoroughly unrealistic for the real atmosphere, especially if you have only one layer. 2) More importantly, although you correctly indicate that the atmosphere can be treated as having multiple layers by simple extension of the gray slab model, in point of fact Postma uses only one. Climate models will typically use 18 or more layers, and they do so because one is inadequate as an approximation to the Earth's (or Venusian) atmosphere. Further, climate models (other than LBL models) will also include terms for the transfer of energy due to convection and latent heat. Without those terms, any multilayer model will predict an excessively hot surface (by 10s of degrees). Without including multiple atmospheric layers, convection and latent heat Postma's claim to be presenting the "standard model" is simply false. Rather, he is introducing the introductory model introduced in Climate 101 in one lecture and superceded by the end of it. As Postma's conclusions follow only follow only for this instructional model, and not for the actual models as used by climate scientists, his paper should be regarded in the same light as a paper purporting to disprove quantum mechanics by demonstrating flaws in the Rutherford model of the atom. I will leave readers to draw their own conclusions about rebuttals and credibility.
  23. Sea level fell in 2010
    I didn't see this graph in the discussion, so I submit it because the correlation between Multivariate ENSO Index and detrended-corrected global sea mean level seems eloquent : Source
  24. It's cooling
    DB) Your sudden, laser focus on short, statistically insignificant timescales is rather puzzling, given your earlier comment: ************* Since my point is that the sine wave has turned negative and that we have entered a time of cooling because of more La Nina's than El Nino's the short term cooling is entirely germane. http://www.woodfortrees.org/plot/hadcrut3vgl/from:2005/plot/hadcrut3vgl/from:2005/trend http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml A negative PDO doesn't guarantee all La Nina's it just means the dice are loaded. The El Nino of 2010 caused a blip of warming. Since 2011 is a La Nina year and predictions seem to predict that 2012 will be too. http://www.cpc.noaa.gov/products/analysis_monitoring/lanina/images3/nino34SSTMon.gif It doesn't make much sense to focus on the 1978 to 1998 warming since conditions have changed since then. The sea level has gone down by 1/4 inch in the last year or so as you might expect if it were cooling. [short term] http://sealevel.colorado.edu/ I contend that we are at the start of a 20 to 30 year cooling cycle.
  25. Understanding climate denial
    elsa#219: "The problem with the AGW theory is that there is no set of circumstances that could prove it wrong." Now that's just flat silly, isn't it? Let's suppose the 'natural cycles' people are right and the next 20 years drop off the charts for no apparent reason. But on the other hand, how do you 'prove' that the natural cycles theory - or more to the point, how do you falsify it? By your standard, 'it's natural cycles' is not a scientific theory. More like wishful thinking; but that is the very heart of denial: You can only wish away so much evidence before you start looking ridiculous.
  26. Joseph E. Postma and the Greenhouse Effect
    Chris Colose, I would like to point out that in the first diagram, Fig 1., shown above, the expressions given by JP are in fact correct, but appear to be misinterpreted in your rebutal here. The factor "f" is simply the fraction of energy/power/intensity radiated by earth absorbed by the single slab, and 1-f is the fraction that escapes. The tempoerature given in these two expressions is Ts not Ta. The latter is the temperature of the atmosphere, and so the power radiated up and down from the surface of the slab is correctly goven in the figure as Sigma*TA^4. The emissivity and absorptivity are taken to be equal to 1. This diagram is a very standard representation in applications to a "layer" whether there is only one or several. As you will be aware, one has to be very careful in a rebuttal as you lose credibility very quickly.
  27. Pielke Sr. and SkS Warming Estimates
    paulhtremblay @54, with respect, while the 28% figure is the topic of this thread, it is not key to the wider debate. Given that many opponents of global warming are willing to take points of of context, the 28% figure needed to be discussed, but given time constraints on the participants, it is perhaps better to move on. Having said that: 1) if Dr Pielke would actually state the argument that his questions about water vapour have been alluding to, rather than fencing around the edges, I believe he raises a substantive (although incorrect) issue. As it stands, his question is purely a hypothetical and not worth further discussion of he will not be plain in his argument. 2) I for one have several more points I could raise against various of Dr Pielke's comments. I am willing to shelve them for now in the interests of moving to the more substantial point with regard to Dr Pielke's position of Land Cover and Land Use Changes, and the gradient of radiant forcing. However, if others are interested I (and perhaps Dr Pielke) can revisit the issue once we have discussed more substantive matters.
  28. Greenland ice loss continues to accelerate
    #20 The reduction in the number of calving glaciers only occurs with significant thinning, which means more of the ice sheet is at a lower elevation so actual melting will increase, while iceberg calving would decline. Many of the calving glacier would tap well into ice sheet before not having their feet in the water. Take a look at the Petermann and Humboldt for example.
  29. Pielke Sr. and SkS Warming Estimates
    pdt @51, it is true that the rhetoric of global warming tends to center around CO2, in part because it plays so large a role compared to any other single agent, and in part because it is easier to say than "Long lived green house gases". However, legislation (and proposed legislation) to deal with the issue tends to tax all LL GHG in terms of their "CO2 equivalent" levels. Other abatement measures are also focused on other forcing agents. In Brisbane, for example, the CSIRO is developing fodder for cattle that reduces methane emissions. Elsewhere, I believe they are working on dry land rice varieties which will have the same effect (although they have other reasons). Hansen has strongly recommended limiting BC as an early response to global warming both because of its low cost as an abatement measure. Given this, it is worthwhile noting that LL GHG represent 72.3% of total forcing since 1750 (Skeie et al), or 55.6% (Pielke's 2006 estimate with mathematical errors corrected). Again this proportion will rise with time if effective emission reduction strategies are not adopted. Industrial pollutants (tropospheric ozone and BC) constitute 22.8% of all forcings (Skeie et al), or 24.9% (Pielke corrected). In any terms, these are a substantive proportion and I agree with Hansen that we should target these "low hanging fruit". Having said that, must of these emissions come from China and India (now), and will dissipate in any event when increased prosperity leads to pressure for clean air acts.
  30. Pielke Sr. and SkS Warming Estimates
    Dr. Pielke writes: >>The real substantive issue, however, which no one on this weblog seems to want to debate, is my (and my colleagues) conclusion that The substantive issue is that the net positive anthropogenic radiative forcing is much greater than 28%, the topic of this posting and the debate, as SkS made this absolutely clear from the start. If you really felt this topic trivial, that it didn't matter if the fraction amounted to 28% of 48%, you needed to state that from the outset. It would have been simple to do. Instead, you engaged in a debate, tried to defend your position, and some 49 posts later, declare that the debate is really about your hobbyhorse, namely, that "The IPCC Has Provided An Inaccurate Narrow Perspective Of The Role Of Humans." Since you have made the claim of 28% multiple times, I would think you would want to stand by it.
  31. It's a natural cycle
    Kat77#7: Here is some evidence. And more evidence. Even more evidence. And for balance, a discussion of your natural cycles. Now weigh the evidence.
  32. Pielke Sr. and SkS Warming Estimates
    This is a good point by Rob Honeycutt in comment #51, as evidenced by the "skeptic" blog posts focusing on the claim that CO2 is only 26-28% of the net positive forcing, as I noted in comment #47. When you're featured on a site like Junk Science, it should give you great pause. Rob's comment bears reiteration:
    "When Dana takes on your statement about 28% of forcing I see something totally different than you. I see all the people who take that statement from "Dr Pielke Sr" that "it's only 28% of the forcing" and I see how that gets translated in the real world. It comes out as, "See! Dr Pielke says we don't need to worry about CO2." And I don't think that's the message that you want to project, but that is what gets propagated. That is what SkS is fighting."
    This is indeed one reason why we put so much focus into this issue.
  33. Pielke Sr. and SkS Warming Estimates
    Dr. Pielke, the reason we got 'hung up' on this issue is that you kept coming up with new (but still incorrect) arguments why the CO2 contribution must somehow be significantly less than 50% of the net positive forcing. Every new explanation you come up with requires investigation to determine if the argument has any validity. Perhaps you would have been better served to accept the calculations putting the value at ~50%, as opposed to constantly trying to find new reasons to validate your opinion that the value must somehow be lower. Then we could more easily move on to other topics, instead of getting 'hung up'. However, at this point I concur that we should move on to other issues. Note that we have moved on to point #2 in the Disagreements post.
  34. Pielke Sr. and SkS Warming Estimates
    Dr Pielke @ 48... I just read your paper that you provided a link to titled... "Climate Change: The Need to Consider Human Forcings Besides Greenhouse Gases." I'm not sure you're going to get a ton of argument on that issue. Quite honestly, you actually might get more argument on much of what is stated in your paper on Anthony Watts' site. I think maybe a little perspective is in order here. You have to look at what SkS is doing. SkS tries to address the fact that a large number of people in the general public are not taking a skeptical approach to climate science. SkS is mostly addressing very elemental scientific facts that are being obfuscated by a large number of people out there. (And on top of that, trying to report on what new is coming out in the published research.) I can attest to the fact that I, and I'm sure many of the authors here, spend an inordinate amount of time on the internet arguing with people who make claims like: There is no greenhouse effect. AGW contradicts the 2nd law of thermodynamics. It's not actually warming. Volcanoes put out more CO2 than humans. The warming is being caused by the sun. Arctic ice is actually recovering. CO2 is too small a part of the atmosphere to have an effect. And on and on. What I think you are approaching has to do with issues of policy and the IPCC. The process the IPCC goes through can always be improved. Policy makers need the best information possible if humanity is going to deal with what could be a very critical issue. But what I think happens is that gets twisted around in the blogosphere into "the IPCC can't be trusted." There is so much blatantly wrong and misleading information being propagated out there in relation to climate change that it is extremely concerning to people here. I believe John Cook and all the SkS authors want to make sure that correct information - information that is digestible for the general public - gets voiced. When Dana takes on your statement about 28% of forcing I see something totally different than you. I see all the people who take that statement from "Dr Pielke Sr" that "it's only 28% of the forcing" and I see how that gets translated in the real world. It comes out as, "See! Dr Pielke says we don't need to worry about CO2." And I don't think that's the message that you want to project, but that is what gets propagated. That is what SkS is fighting. A friend of mine told me once, "In a conversation, always try to listen for context over content." Try to listen to why people are saying what they are saying, not just what they are saying.
  35. Understanding climate denial
    #219, 1: demonstrate that CO2 does not scatter IR radiation; 2: demonstrate that IR scattering is not happening in Earth's atmosphere; 3: demonstrate that we are not increasing the concentration of CO2 in the atmosphere significantly; 4: demonstrate that this IR scattering due to CO2 is not significantly increasing, thus increasing the energy present in the Earth system; 5: demonstrate that the energy present in the Earth system (most often measured as temperatures) is not increasing over statistically significant timescales; 6: demonstrate that the extra energy scatterd by CO2 is escaping the Earth system another way. There you go, six easy pieces, each of which is falsifiable, and I'm sure there are many more. Elsa, your unsubstantiated musings are wrong, once again.
  36. Pielke Sr. and SkS Warming Estimates
    I don't know if Dr. Pielke has given up on this thread yet, but I would like to just express my understanding of what he means when he says it doesn't make a difference if the anthropogenic forcing is 30% or 50% CO2. In that range, 50-70% of anthropogenic forcing is not CO2, which means those other things should probably account for 50-70% of the discussion about global warming. From my perspective that is certainly a valid argument. I assume that is the point of his argument, but perhaps I'm wrong. The question in my original post (#21) is related to that. How much of the anthropogenic forcing can be reasonably attributed to fossil fuel extraction/burning regardless of the mechanism for forcing (CO2, methane, aerosol, black carbon, ozone, etc.)? The answer to that question may make the current focus of the public discussion seem more in line with reality.
  37. Understanding climate denial
    #214 Jonathon, the 'large range of values' does not include zero or anything particularly close to it (for warming rate and sensitivity). We also have both a clear physical mechanism (CO2 scatters longwave IR) plus the supporting observations showing that it is this physical mechanism that is operating, and still further we have no alternative natural mechanism to drive the warming. Since this is the case, we can pretty straightforwardly have a consensus that it is warming and largely due to human activities. If the range of values for warming or sensitivity included sufficiently low values, then there would be some doubt. If you are travelling at a speed of between 50 and 200mph towards the base of a cliff 100m away, with no brakes, is there anything other than a consensus as to the outcome for the 100 scientists watching? Does the precision of the reading on the speedometer matter?
  38. Understanding climate denial
    We should be very grateful to the late Sir Karl Popper for his insight into what constitutes a scientific theory and what does not. A scientific theory is one that can be falsified. The problem with the AGW theory is that there is no set of circumstances that could prove it wrong. That is why I have compared it to Marxian theories of "inevitable" trends and Freudianism, both with their trappings of science but without the capability of being falsified.
    Response:

    [DB] Perhaps you missed this earlier response:

    Additionally, from the NAS publication Advancing the Science of Climate Change (Pp 21-22):

    Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. 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.

    [Emphasis added]

    As for:

    "The problem with the AGW theory is that there is no set of circumstances that could prove it wrong."

    Actually, many things come to mind.  For example, come up with a testable hypothesis showing that the radiative physics of anthropogenically-derived CO2 do not behave similarly to those of CO2 already present in the carbon cycle.

  39. Pielke Sr. and SkS Warming Estimates
    Methane: A brief review of the comments did not find anyone who noted the foundation of the Shindell methane estimate of 0.8 W/m2: this is an emissions based estimate, not a concentration based estimate. Shindell's calculations looked at eliminating historical methane emissions (since 1750), resulting in a forcing 0.8 W/m2 lower today: that 0.8 would come partly from an increase in CH4 concentration but also an increase in O3 concentration, stratospheric water vapor, and (this was the novel contribution of the Shindell paper) a reduction in sulfate loading. In contrast, the IPCC estimate is based on concentration of CH4 only. (note that if you use Shindell's estimate, than you can't also use O3 forcing as a separate row - that is definitely double counting). Black carbon: I will note that the Hansen & Nazarenko estimate of 0.3 W/m2 of snow albedo forcing was obsolete even before it was published, as it was a result of a calculation error (as noted in a later Hansen paper). AR4 estimated 0.1 W/m2, and more recent papers are slightly lower. Of course, since AR4 estimated the direct BC effect at 0.34, for a total of 0.44 (I'd correct the SKS table to reflect that), this isn't a big deal. Though... since BC is rarely emitted without co-emissions of organic carbon and other cooling aerosols, I'm not sure it belongs in this kind of calculation. Ozone: I don't know why Pielke Sr. thinks that it is a good idea to extrapolate a result for ozone warming in the Arctic in two seasons to annual global forcing. Albedo: I also don't know why he thinks that a 4 year trend is appropriate to compare to forcing since 1750. I'll note that AR4 estimated -0.2 W/m2 for the long term surface albedo contribution. This probably isn't directly comparable to Pielke's CERES results which are presumably dominated by short-term cloud changes. Head-of-a-pin: All of this is a bit like counting angels, especially when you begin to throw in aerosols, because of the negative and positive contributions. Is 1.66 W/m2 100% of net forcing? 50% of the SKS list of forcings? 45% if you include black carbon but not BC co-emissions? Whatever. It is pretty clear that CO2 is the single largest contributor to recent and projected future warming, even if it isn't the only contributor globally, and the regional picture gets more complicated with urban heat islands and ENSO variability and so forth.
  40. It's a natural cycle
    is climate change a natural cycle. i don't want to know that it is or isn't. i want to see some evidence plaease.
    Response:

    [DB] Try here.

  41. Pielke Sr. and SkS Warming Estimates
    dana1981 - Your comment and that of the others show why it is futile to debate on this website. You get hung up on one issue where we disagree. I never focused on the estimate of the fraction of positive radiative forcing (either currently or the change from pre-industrial times) as a primary reason why we need to broaden beyond the radiative effect of CO2. This need is equally true if the fraction is 28% or 50% (or 100% for that matter). My estimate of the fraction of CO2 was to illustrate with reasonable interpretations from the literature that it may be less than reported in the IPCC report. I came up with ~28%. I adopted a different approach in my response on this weblog post, accepting for the sake of discussion several of your conclusions on the forcing and starting from your fraction and then working with a realistic estimate of black carbon and the two indirect aerosol effects, and the longer period of influence of CO2 to come up with a smaller fraction. We do not agree on the fraction. In terms of our EOS article and the main issues, this is just a sideshow. The real substantive issue, however, which no one on this weblog seems to want to debate, is my (and my colleagues) conclusion that "The IPCC Has Provided An Inaccurate Narrow Perspective Of The Role Of Humans". We presented this view in our paper Pielke Sr., R., K. Beven, G. Brasseur, J. Calvert, M. Chahine, R. Dickerson, D. Entekhabi, E. Foufoula-Georgiou, H. Gupta, V. Gupta, W. Krajewski, E. Philip Krider, W. K.M. Lau, J. McDonnell, W. Rossow, J. Schaake, J. Smith, S. Sorooshian, and E. Wood, 2009: Climate change: The need to consider human forcings besides greenhouse gases. Eos, Vol. 90, No. 45, 10 November 2009, 413. Copyright (2009) American Geophysical Union.http://pielkeclimatesci.wordpress.com/files/2009/12/r-354.pdf NRC 2005 has the title "Radiative forcing of climate change: Expanding the concept and addressing uncertainties.' Why not discuss these publications? You would likely then expand your readership beyond those who accept the IPCC as a robust assessment of the role of humans on the climate system. I recommend moving on to the other issues. I do appreciate the opportunity to see these counterpoints and will be posting a summary of outstanding questions starting next week.
  42. Pielke Sr. and SkS Disagreements and Open Questions
    Regarding point #2, and the weak selection of 1998 as the point at which the TLT became "~flat", Tamino's How Long post is incredibly relevant for those wishing to statistically determine the length of time required before a significant trend emerges from the noise. Trends from UAH using woodfortrees - 1980-1992, and 1997,1998,1999-present: You can see the 1998 outlier skews trends of 13 years length to be much smaller than the overall trend. A year before or after, as dana shows gives a steeper trend, which happens to be much closer to the long-term trend. 1980-1992 inclusive has a virtually flat trend, that is, 13 years where the noise (and a volcanic eruption outlier) masked the signal.
  43. Understanding climate denial
    elsa, until you broaden your horizons and actually read more about the claims you are making, this will continue to go around in circles, with people here pointing you towards links where you can find the science and evidence, and you just constantly coming back repeating the same things and not getting anywhere. As has already been suggested, you would do well to read Spencer Weart's The Discovery of Global Warming. Will you read that or not ?
  44. Greenland ice loss continues to accelerate
    Interesting observation, the pattern of where the mass loss is occuring along the south & west of Greenland. Compare that to this graphic from Steve Brown's recent post on the Last Interglacial. The loss matches the pattern from the Eemian which is also a small indpendent support for the valifity of the data
  45. Greenland ice loss continues to accelerate
    fydijkstra @ 17 - "The ice loss of the ice cap is accelerating, we are being told every year. Nevertheless the sea level rise does not accelerate, but slows down." The loss of land-based ice has indeed increased and is contributing more to sea level rise than it was in previous decades. See: Revisiting the Earth's sea-level and energy budgets from 1961 to 2008 - Church (2011) From the abstract: "The cryospheric contributions increase through the period (particularly in the 1990s) but the thermosteric contribution increases less rapidly" I think you are confused about the large water mass exchanges between the land and the ocean that occur on year-to-year time frames - which temporarily lowers sea level. See argument 171 - Why did Sea level fall in 2010?
  46. Greenland ice loss continues to accelerate
    Mspelto - Mauri, is it likely that we may see a slowdown in Greenland icemelt in the future, once all the glaciers with their "feet in the water" disappear?
  47. Understanding climate denial
    @elsa #215 Your understanding of the scientific process is incorrect. The report, “Science, Evolution, and Creationism,” issued by the National Academy of Sciences and the Institute of Medicine in early 2008, defines scientific theory and scientific fact. “Theory: A plausible or scientifically acceptable, well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of circumstances to explain a specific set of phenomena and predict the characteristics of as yet unobserved phenomena.” “Fact: In science, a ‘fact’ typically refers to an observation, measurement, or other form of evidence that can be expected to occur the same way under similar circumstances. However, scientists also use the term ‘fact’ to refer to a scientific explanation that has been tested and confirmed so many times that there is no longer a compelling reason to keep testing it or looking for additional examples."
    Moderator Response:

    [DB] Additionally, from the NAS publication Advancing the Science of Climate Change (Pp 21-22):

    Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. 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.

    [Emphasis added]

  48. Understanding climate denial
    Albatross, Remember though, it was not "skeptics" who originally peddled the consensus argument. Neither side of the argument holds much water.
  49. It's cooling
    Tamino answer's part of #160 Tor B's comment at with a recent post on Arctic temperatures using NCAR data. He has a number of interesting graphs for the 80-90N region, and they appear to show significant warming in that region. I'm unsure as to the mechanisms discussed at Neven's blog however as the link is to his homepage.
  50. Understanding climate denial
    CB Dunkerson and Sphaerica and Lloyd Flack Trying to keep things very much to this specific topic what I am saying is that it is impossible to prove a theory as right. The best we can do is to demonstarte that it is not false and indeed for me this is the definition of a scientific statement. If is cannot be falsified it is not scientific. This is where the warmist view falls down and why what you call denialism will continue. I have not denied that there is a link between CO2 and temperature. What I would deny is that we know what it is or can test the hypothesis in any meaningful way. We are not given a link by physics we simply do not know the relationship and if you disagree with that tell us what it is. In addition I would say that what you call denialism survives because the warmist view is so often apocalyptic and so full of knowledge (which it does not really possess. The danger here is that the truth which is that there may be a problem) is thrown out with the nonsense that is peddled as science. I am not sure if it was one of you but the reaction to my statement that there are other factors that move sea level apart from temperature was greeted by one participant with the statement that (a) there were no such factors other than eg meteorites and (b) that since warming was the only explanation available it must therefore be right. This is a good example of how "denialism" may win. The first statement merely demonstrates the writer's ignorance and the second is wrong as a matter of logic. Simply because we have only one explanantion for something does not make it right, any more than 14th century doctors were right in their analysis of the plague because bad humours was the only explanation.
    Response:

    [DB] "I am not sure if it was one of you but the reaction to my statement that there are other factors that move sea level apart from temperature was greeted by one participant with the statement that (a) there were no such factors other than eg meteorites and (b) that since warming was the only explanation available it must therefore be right."

    Actually, I believe it was CBD, here (feel free to correct me if it was a different commenter).  And I believe you mis-quote him.  I suggest you re-read it in its entirety (since you are unsure).  In case of a language barrier, the examples given were ironical/fascetious.

Prev  1449  1450  1451  1452  1453  1454  1455  1456  1457  1458  1459  1460  1461  1462  1463  1464  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us