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  1485  1486  1487  1488  1489  1490  1491  1492  1493  1494  1495  1496  1497  1498  1499  1500  Next

Comments 74601 to 74650:

  1. SkS Responses to Pielke Sr. Questions
    I will note that the recent increase in 'skeptic' blogs attacking SkS is actually a compliment - Bishop Hill, Pielke, Watts, JoNova, etc., are taking the information here seriously enough to denigrate it. That said, I would encourage moderation in the rhetoric in return. When someone without an axe to grind comes upon a discussion, the person ranting is likely to be dismissed. I will always treasure the episode on JoNova's blog where one of the regular skeptics was told by the site moderators to tone things down, as his accusations of 'liar!!!' were making me look good. Let's take the high road, eh?
  2. SkS Responses to Pielke Sr. Questions
    John (Hartz) my post (and this may be true of some of the others) is (a) a highlight of what I imagine many posters would find very useful and relevant, and (b) refers to Drs Pielke in reference to the general policies of these individuals. I do agree with your sentiment, but in that case it might have been better to put an embargo on comments on this thread until Dr Pielke responded. If you open a thread for comments you can't not expect to receive them...!
    Moderator Response: [John Hartz] Because I am a relative newcomer to the ranks of SkS Moderators, I have yet to delete anyone's posts on a comment thread. I would, however, point out that you began your post with "This is slightly off topic..." Otherwise, your points are well taken.
  3. Are you a genuine skeptic or a climate denier?
    KR, Does the whole argument rest on "product of the atmosphere"? I misspoke, I meant to say CO2 is part of the atmosphere, and if the atmosphere doesn't drive climate, then CO2 doesn't drive climate. That is a basic syllogism.
  4. Are you a genuine skeptic or a climate denier?
    Dana69 - "The atmosphere does not drive climate. CO2 is a product of the atmosphere." Really - such amazing statements... So the 29-30 billion tons of CO2 from our yearly emissions are a 'product of the atmosphere'? And the world isn't 33C warmer than it would be without greenhouse gases? As I said, denial. Until and unless you actually read up on the science, I don't think it's worthwhile discussing matters with you. I would suggest The Carbon Dioxide Greenhouse Effect as a starting point. As to the uncertainties in various values - they exist. But, you appear to be certain that the numbers are zero, when all evidence points to non-zero ranges. So based on some uncertainty you are claiming values outside any range supported by evidence. That's not rational at all, and in fact is a logical fallacy.
  5. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee#71: "orbital momentum of the sun undergoes a forty to one increase" 'Orbital momentum'? Do you mean 'angular momentum'? And how does a change in momentum of any kind have anything to do with cosmic rays? "As Shaviv showed, GCRs can account for very large changes in climate" Shaviv 2005 shows this: the CRF/climate link therefore implies that the increased solar luminosity and reduced CRF over the previous century should have contributed a warming of 0.47 ± 0.19°K, while the rest should be mainly attributed to anthropogenic causes. That's if there is a CRF/climate link, a point that has not yet progressed beyond mere hints.
  6. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee, Shaviv showed nothing of the sort. Shaviv (and Veizer) made a tentative hypothesis that the passage of the Earth through the spiral arms of the galaxy might modulate the cosmic ray flux on 100's of million year time scale with a broad cyclic effect on Earth temperature. There is no evidence that this hypothesis has merit, and Shaviv's coauthor Jan Veizer, reassessed his temperature reconstruction and concluded that the temperature variation through a major part of Earth history doesn't actually correlate at with the putative CRF effect at all. In fact Veizer concluded that the major determinant of Earth temperature in the deep past is atmospheric [CO2]: R.E. Carne, J.M. Eiler, J. Veizer et al (2007) Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era; Nature 449, 198-202
  7. Are you a genuine skeptic or a climate denier?
    KR, We both come to conclusions in different ways. If you are comfortable with the level of uncertainty, and are willing to act using the precautionary principle, so be it, but that does not in of itself validate the argument. The atmosphere does not drive climate. CO2 is a product of the atmosphere. It can have some affect, but the amount and extent is a large variable up for discussion. Try to quantify that.
  8. Are you a genuine skeptic or a climate denier?
    Ugh - KR - you beat me to it. Forget leaving the house--simple thought, having been rendered functionless, would be almost impossible.
  9. SkS Responses to Pielke Sr. Questions
    In my opinion, the first five posts should be withdrawn or deleted because Dr. Pielke has not yet responded to Dana's article. It's rather cheeky to assume that one knows in advance what Dr. Pielke's response will be.
  10. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    The paper is a bit old because Landscheidt died in 2003. He did publish in refereed journals such as Solar Physics and Climatic Change. The Journal of Coastal Research Special Issue No. 17 (1995), p 371-382 included the paper I referenced. The orbital momentum of the sun undergoes a forty to one increase and decrease due to the various planets orbital relationships. As Shaviv showed, GCRs can account for very large changes in climate including the very large swings from ice age to warm periods. Hardly a "minor effect." Here is another paper that shows that relationship and also discusses the accurate predictions of La Nina and El Nino periods based on planetary gravitational effects on the sun. http://www.john-daly.com/sun-enso/revisit.htm Most of the distressing weather this year including the famine in Somalia, floods in Australia and the US midwest were caused by the same La Nina that Landscheidt predicted using sound science a decade ago. Thanks for the good comments but I really feel that a theory is only as good as its ability to predict and I remain very impressed with the solar/cloud connection.
  11. SkS Responses to Pielke Sr. Questions
    Looks like many of the questions were designed for entrapment. I'm amazed there wasn't "do you still beat your wife?"
    Moderator Response:

    [John Hartz] Which set of questions are you referring to?

    [Daniel Bailey] Inflammatory struck out.

  12. Are you a genuine skeptic or a climate denier?
    Dana 69 - Ah, yes, "there seems to be valid reasons to doubt", the Argument from Uncertainty claim, which is a logical fallacy. You seem to be arguing that because there is some uncertainty in certain aspects (exact sensitivity, for example), that you can dismiss the entire field of science. If you were to actually believe that and apply it in real life, you would never leave the house. Exact values of cloud feedback? Indirect aerosol effects? Long term climate sensitivity? There's some uncertainty, a range of values. But the fact that there is a significant climate sensitivity? No uncertainty there. Noting a particular value is fuzzy does not support claiming it has a zero value. That's a frequent error I see in discussions here - and unsupported by the evidence. In fact, that would be denial.
  13. SkS Responses to Pielke Sr. Questions
    This is slightly off topic but maybe not so much, since Dr. Denning (see below) might well be speaking to Drs. Pielkes. This is Scott Denning's enlightening and passionate talk (v short) at the....Heartland Institute pseudoscience climate conference. For those that might wish to resist looking at such a thing, Dr. Denning is a proper scientist and makes a great job of skewering the self-defeating bluster of quite a number of types of pseudoskeptics. Highlighting this and its implication would almost be worth a thread of its own...
  14. Hockey stick is broken
    Eric, no we're talking about the same thing. McIntyre's nonsensical argument about the '12 proxies' has been around for a few years. Seriously. 'Crack cocaine'? For PROXY temperature values since 1988? You do realize that we have these things called thermometers, right?
  15. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    dana1981 - Thanks, I should have searched a little more. The Eastman 2011 paper is particularly interesting to me - some time back, in discussion with one of the resident skeptics here on SkS, I came across the ship report data that seemed to indicate a positive feedback. However, I didn't have the time to assemble all the reports (54 million!), so I didn't do any serious analysis of it.
  16. Are you a genuine skeptic or a climate denier?
    If climate is deterministic in nature you could have reasonable assurance of the outcomes. If more stochastic (governed by the laws of probability) it would be problematic. Seems most arguers here land on the deterministic side. But consider the following statement by the IPCC Working Group I: "This considerable advance in model design has not diminished the existence of a range of model results. This is not a surprise, however, because it is known that climate predictions are intrinsically affected by uncertainty (Lorenz, 1963). Two distinct kinds of prediction problems were defined by Lorenz (1975). The first kind was defined as the prediction of the actual properties of the climate system in response to a given initial state. Predictions of the first kind are initial-value problems and, because of the nonlinearity and instability of the governing equations, such systems are not predictable indefinitely into the future. Predictions of the second kind deal with the determination of the response of the climate system to changes in the external forcings. These predictions are not concerned directly with the chronological evolution of the climate state, but rather with the long-term average of the statistical properties of climate. Originally, it was thought that predictions of the second kind do not at all depend on initial conditions. Instead, they are intended to determine how the statistical properties of the climate system (e.g., the average annual global mean temperature, or the expected number of winter storms or hurricanes, or the average monsoon rainfall) change as some external forcing parameter, for example CO2 content, is altered. Estimates of future climate scenarios as a function of the concentration of atmospheric greenhouse gases are typical examples of predictions of the second kind. However, ensemble simulations show that the projections tend to form clusters around a number of attractors as a function of their initial state. They do not specifically say so, but the reference to Lorenz and the use of “attractor” imply that chaos theory is being invoked here not determinism. Stochasticsm seems to be the statistical model on which climate prediction is based. Many climate modellers share this view, e.g. Stainforth et al (2007), viz.: "weather is chaotic and climate may be taken as some 'attractor' of weather." I know this thread is about skepticism as a whole, and this may seem off point, but it goes to the heart of why someone would be more skeptical to the overall conclusions of climate arguments. Meaning, there seems to be valid reasons to doubt.
    Moderator Response: There is a thread for that. Type "chaotic" into the Search field at the top left of this page. And take this discussion there, please.

    [Dikran Marsupial] I have responded to this post here. Any further discussion of chaos theory on this thread is off-topic.
  17. Hockey stick is broken
    Eric, You did not look at the date and time did you? :) If you think it is OK for McIntyre liken paleo climate scientists to crack cocaine addicts, then by all means go ahead. You honestly think that it is perfectly OK for someone to use that kind of language in a scientific discussion. Got it. Maybe you ought to direct your questions to Dr. Briffa, but I would caution you that you are operating under the dangerous assumption that the information that you have been fed by Mr. McIntyre is accurate.
  18. SkS Responses to Pielke Sr. Questions
    Albatross (#3), The 2nd link from Nov. 2009 might have been the follow-up, or maybe this post: But they also laughed at Bozo the Clown Dr. Pielke Jr. (-snip-) gets into tribal discussions and tone. No surprise. On global warming metrics, trends, and deep ocean heat, there's a new paper out, discussed here: Deep Oceans Can Mask Global Warming for Decade-Long Periods
    Moderator Response: Let us not get too excited.
  19. Hockey stick is broken
    Albatross, I came to this thread to defend one McIntyre comment (singular). The other one brought up in the other thread was undefendable (Hansen refusing to debate Christy = Jihad). If you don't agree, then address my post 91 and explain why crack cocaine is not a good analogy for Briffa Yamal. Please explain why two other series in the peer reviewed literature that cover the same location were always passed up and Briffa Yamal was used in reconstructions instead.
  20. Hockey stick is broken
    May I presume that you share my sentiments that no one would conclude that the Earth has cooled based on these areas?
  21. Hockey stick is broken
    111, Jonathon, From your paper (emphasis mine):
    A notable feature of the observed trend map for the past century (Fig. 7a) is the pervasiveness of the warm- ing on the regional scale: almost all areas of the globe analyzed appeared to have warmed over the twentieth century. A few relatively small areas of cooling are seen, including a region south of Greenland and an- other covering the southeastern United States. The cooling trends in these regions generally do not appear to be statistically significant according to comparison with the control run 100-yr trends (Fig. 7b). On the other hand, the warming trends over much of the globe are statistically significant (compared to internal cli- mate variability) according to these tests.
  22. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    We discussed Clement and a number of other relevant papers in the rebuttal to 'clouds provide negative feedback'.
  23. SkS Responses to Pielke Sr. Questions
    NewYorkJ @2, Thanks for posting those links-- do you have more? From the first link: "I've got a lengthier post in the works, but since Roger Pielke Sr is demanding a response..." Dr. Pielke appears to like demanding things and asking others to answer his his carefully crafted questions.
  24. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    Clement et al 2009 also supports positive cloud feedback to warming. They used observational and model data for the Northeast Pacific. "The observed relationships between cloud cover and regional meteorological conditions provide a more complete way of testing the realism of the cloud simulation in current-generation climate models. The only model that passed this test simulated a reduction in cloud cover over much of the Pacific when greenhouse gases were increased, providing modeling evidence for a positive low-level cloud feedback."
  25. SkS Responses to Pielke Sr. Questions
    Other than a quote by McKitrick, I haven't seen much discussion of Dr. Pielke's overemphasis on land use. Some critiques of his claims. Bizarre Rewriting of History Klotzbach ad Nauseam Pielkes all the way down, Revisited Perhaps there could be an expansion of the land use category. Roger's Ruses? As Albatross indicates, expect some long-winded and convoluted dancing to the questions posed. Possibly related, his colleague Anthony Watts posted a Fox News interview with Dr. Pielke some time back. I say "possibly" because the video has been restricted for public viewing. Anthony Watts: Dr. Roger Pielke Sr. to be on Fox Business News But we always have the astute commenters of the "excellent" (as Dr. Pielke calls it) WUWT blog to give an accurate representation of the interview. Some quotes: "In just a couple of minutes Dr. Pielke made the essential point that you cannot regulate the Earth’s climate by manipulating CO2. This point absolutely destroys the basic premise underlying so-called ‘climate’ legislation (and the EPA decision that CO2 is a ‘pollutant’)." "I think that Dr. Pielke gave a very politically astute interview. Any politician and any student of the vocabulary used by politicians will recognise a perfectly delivered slap-down of the appointment of Karl’s appointment. It was given in a measured, calm and rational manner making it even more devastating. Well said, Dr. Pielke. The opponents of CAGW need spokesman like you, the very antithesis of the hysterical pro-AGW propagandists." "His main message was that Tom Karl was the wrong man to lead Obama’s new climate centre, as he would stifle the freedom of the team to look at all aspects of the science. He also indicated that reducing CO2 was not the answer and that the money would be better spent identifying areas of risk of drought, for example and spending money to mitigate the effects."
  26. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    Alb: "Additionally, the GCR theory would then just become part of a whole suite of climate drivers, it would not in any way shape or form refute the known radiative forcing properties of GHGs, and thus would not in any way refute the theory (not hypothesis) of AGW." That can't be said enough. It could turn out that GCRs are the primary driver of climate. As improbable as that is, it would still in no way prevent GHGs from warming the atmosphere relative to an atmosphere with no GHGs. This recognition should be named the Doug Cotton Test for being taken seriously.
  27. Hockey stick is broken
    Eric, Please follow this link. Note the date and time. Some of us prefer to live in the present, but to plan for the future, not just for ourselves but also for future generations. I'm disgusted that you chose to defend McIntyre's vitriolic and hateful comments-- and now seem to be trying to use them as a reason or "in" to challenge the dendro plaeo records. It seems to me that you agree with his propaganda on this file? Have you applied, as your moniker suggests, skepticism, or just one-sided skepticism like Pielke et al. do? Surely you aware of the multiple, paleo hockey sticks out there?
  28. Hockey stick is broken
    #93, CBDunkerson, we appear to be talking about two different things. In my post 91 I demonstrated that the analogy that the "Yamal 12" (referring to 12 cores post 1988) are analogous to crack cocaine by pointing out the other data sets that were available with 30 or more cores during the same period. Divergence is a discrete phenomenon that causes some trees in some places to show slow growth due to non-temperature factors. But it is certainly not valid to claim that trees that don't show divergence (i.e. are not overtly impacted by those unknown factors) are sufficient for reconstructions "because we all know it has gotten warmer". The last part in quotes is ture, but the first part does not follow. It is equally possible that those faster growing trees are impacted positively by another unknown factor. The crux of the problemn with Briffa 2000 is not divergence but inadequate numbers of cores.
  29. Philippe Chantreau at 03:48 AM on 21 September 2011
    Chasing Pielke's Goodyear Blimp
    I like Paul from VA's suggestions.
  30. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee, I am not sure whether or not you are issuing a plea or a challenge. And what you linked us to it is not a published science paper but an essay on a blog. Even if the CGR hypothesis were very real and shown to be a theory and that CGRs do in fact modulate the global climate, then the changes would be very small and infrequent. Additionally, the GCR theory would then just become part of a whole suite of climate drivers, it would not in any way shape or form refute the known radiative forcing properties of GHGs, and thus would not in any way refute the theory (not hypothesis) of AGW. Moreover, if the aforementioned happens to be true, then it does not explain the observed fingerprints that have been associated with warming on account from increased GHGs. So I do not understand your eagerness to join those who deny the theory of AGW based on a hypothesis or a blog essay, when we have all these data, science and facts demonstrating that CO2 is driving a significant portion of the warming that we have witnessed over the past 100 years. And I am not sure what predictions made by Landscheit are now allegedly coming to fruition you are referring to. One of them is ertainly not this one: "a long period of cool climate with its coldest phase around 2030 is to be expected." Besides, research has found that even if solar forcing were to decrease to a maunder-liek minimum for a long time, it would have a very minor impact on global temperatures. SkS has covered this here. Now none of this is to try and claim that the sun is not important for regulating the earth's climate, of course it is. The point is that solar changes cannot explain the warming of around +0.8 C observed the past 100 years or so, and even if we went into a maunder-like minimum, the current and future levels of GHG forcing from burning fossil fuels and land-use change by humans will more than offset any negative radiative forcing or cooling.
  31. Philippe Chantreau at 03:35 AM on 21 September 2011
    CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakesele, the link you provide does not lead to a paper but what appears to be some sort of presentation. I am not sure what exactly you think are the "predictions" that are coming true. Landscheidt cite 2030 through the following hundred years or so, so we are not there yet. It is interesting to note that 2005 is among the top 10 warmest years recorded, with 2010, and 2011 likely to be right up there too, while the Sun is in one of the most quiet period we have observed. I further notice that the Landscheidt presentation is dated and many of these graphs would benefit from adding the data of recent years, which will show quite a different picture. I am puzzled as to why Landscheidt would not want to examine statistical significance on the Vostok figures. Eyeballing leads to all sorts of misconceptions, why not establish whether the correlation is real and quantify it exactly? Furthermore, I recommend you to read through the thread, where Muoncounter, the well-named, counted how often exactly these Forbush events happen. It boils down to a few noticeabl events per year. Whatever effect on clouds these events have would have to be colossal (as in major weather event) in order to affect the climate. Colossal effects observable in the real world are all but absent. I am unimpressed by the Landscheidt presentation.
    Moderator Response: [muoncounter] Landscheidt passed away in 2004.
  32. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee: The 'sharp decrease in cosmic rays' are Forbush Decreases; my comments on the Dragic paper suggest that the effect on climate of these short-term events is not robust. I've looked briefly at this Landscheidt site; it looks to me like Ptolemaic cycles and epicycles. Add enough loops and you can 'predict' anything. One of their main predictions is the coming Ice Age. Instead, we have the hottest decade on record. Of what value is a model that makes atmospheric/oceanic behavior predictions without any reference to the physics of either the atmosphere and/or the oceans?
  33. Skeptical Science now an Android app
    the qr-code is not working. i tried it with qr droid. if i try to open the url from the qr code i get a 404 error.
  34. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee, #64 Skeptical Science rightly doesn't take the opinions of avowed astrologers very seriously, especially when they have repeatedly made the kind of silly claims as he did in the paper you linked to. If anybody doubts he's an actual astrologer, look at his books Cosmic cybernetics: The foundations of a modern astrology and Sun, Earth, Man: A Mesh of Cosmic Oscillations - How Planets Regulate Solar Eruptions, Geomagnetic Storms, Conditions of Life and Economic Cycles.
  35. Observations of Climate Change from Indigenous Alaskans
    Modeator: Permission hereby given. Thank you for your interest.
  36. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee - firstly it doesn't appear that the "paper" you link has been published anywhere. Secondly, the quality is quite poor. For example, its Figure 4 shows the ridiculous solar cycle length vs. temperature graph from Friis-Christensen and Lassen, which conveniently stops in 1980, because after that date, the two lines diverge. See our post here on the subject. It's hard to take any "paper" seriously that would cite this long-debunked graph. The "paper" also doesn't address any of the problems in the galactic cosmic ray warming hypothesis that we've pointed out here.
  37. Hockey stick is broken
    Sphaerica, Over a longer time period, there are more areas. http://journals.ametsoc.org/doi/pdf/10.1175/JCLI3709.1 However, I do not think anyone would use just the data from the southern U.S. to from the conclusion that the globe has cooled. I echo your sentiments Chris about using a single site.
  38. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    I'm very disappointed that this blog seems to ignore my posts. I would be happy to see somebody comment on this 2002 paper by Landscheidt: http://bourabai.narod.ru/landscheidt/new-e.htm He seems to have made some amazing predictions based on the cosmic ray/cloud model which are coming true today. I am almost ready to join the deniers based on his work. This blog will not accomplish its purpose if you simply delete inconvenient questions. Please set me straight.
  39. Hockey stick is broken
    103, Jonathan, Oh, wait, if you go by Mann 2010 you're right. That teeny tiny little sliver of western South America has cooled fractionally, along with ocean off the coast of Antarctica. You're right. Any proxy would be a cherry pick if it doesn't include those two critical spots on the globe.
  40. Hockey stick is broken
    103, Jonathan,
    Portions of the globe have cooled during the twentieth century...
    Very, very false.
  41. Hockey stick is broken
    "I think you have highlighted one of the difficulties in using proxy data. Roh234 showed that even recent proxies can result in opposite conclusions." No I didn't Jonathon (@ 95). I've highlighted how easy it is for those that wish to misrepresent the science to do so by selecting individual proxies that support a particular preconceived interpretation. Happily proper scientists continue to make considerable efforts to include as many verified proxies as possible to maximise the spatial coverage to allow assessment of at least hemispheric paleotemperature evolution on the millenial timescale. I'm sure you'd agree that it would be dumb to try to infer something about global or hemispheric temperatures from a single site in the Sargasso sea, particulalry when we have some rather good information that this is rather senstive to changes in the Meridonal overturning circulation that have no necessary relationship to global scale temperatures....
  42. SkS Responses to Pielke Sr. Questions
    I am going to make a prediction here. Dr. Pielke is probably going to write long-winded posts (and not provide succinct answers like SkS has done above), he is likely going to obfuscate, focus and elevate uncertainty, he is probably going to focus on land use change and his favourite metric (OHC), and he may even decide to choose some interesting time periods on which to base his conclusions. In short, he is going to try and convince people of those things that he believes and thinks are important. What are those one might ask? See here for his list of conclusions about the climate system and policy. That is, he appears to have made up his mind already (i.e., uses the title "conclusions"), and appears to have the problem pretty much all figured out. I'll let readers come to their own conclusions. I am more than happy for Dr. Pielke Sr. to prove me wrong. In fact, I hope that he does.
  43. Hockey stick is broken
    Jonathon, #106 "The Lundqvist paper covers the period up to 1999, so it includes the warmest year in the instrument record." In some instrumental data sets you mean. And it doesn't however include the warmest decade (the last ten years). Also, the paper states, "The proxy reconstruction itself does not show such an unprecedented warming but we must consider that only a few records used in the reconstruction extend into the 1990s." The proxy data for the last decades of the study are weaker than the for the rest of it. The instrumental data trumps the proxy data for that time frame. Again, they concluded (with qualifications) that the decades since 1990 seem to be warmer than at any time during the last 2,000 years for the NH. The "highest temperature in the reconstruction" does not mean the highest temperature in the last 2,000 years. They are quite clear about that.
  44. Hockey stick is broken
    KR, The Lundqvist paper covers the period up to 1999, so it includes the warmest year in the instrument record. You need to read the paper (and your quotes) carefully. You are stating that timing and variability agree. However, the paper shows similar proxy temperatures at both the end of the 10th and 20th centuries. You also seem to contradict yourself in your first sentence about the Lundqvist paper to which I presented.
  45. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    Jonathon @10, Of course they did, on interannual timescale in the tropics. You left that first part of the sentence out that specified "interannual" and "tropical". Nice cherry pick. We know that short-term oscillations in the climate system (like ENSO) cannot explain the amount of warming observed between 1954 and 2008. Oscillations modulate the underlying long-term trend, they cannot create it. Please stop trying to obfuscate. I'll remind you of what they said. "However, the decrease combined with observed increases in SST and the negative correlation between marine stratus and sea surface temperature suggests a positive cloud feedback to the warming sea surface." EOS.
  46. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    Albatross, The study also found a strong correlation between cloud cover and ENSO.
  47. Hockey stick is broken
    Jonathan - There's a huge difference between single proxies (as you have presented) and looking at groups of proxies from multiple locations, as Ljungqvist and Mann have done. In the Ljungqvist paper he is speaking about the proxies, which don't extend directly to the present. So your argument about the last few decades amounts to claiming that proxy and instrumental data cannot be joined, despite overlap periods where they can be calibrated. I don't believe that's even remotely justifiable. Also note that, as stated in Ljungqvist 2010: "Our temperature reconstruction agrees well with the reconstructions by Moberg et al. (2005) and Mann et al. (2008) with regard to the amplitude of the variability as well as the timing of warm and cold periods, except for the period c. ad 300–800, despite significant differences in both data coverage and methodology." So - you're trying to use Ljungqvist, who agrees with Mann and Moberg, to argue against Mann and Moberg regarding the MWP??? That argument simply doesn't hold up.
  48. Hockey stick is broken
    Jonathon, the proxies in the Lundqvist paper do not include the last few decades. That the highest temperatures in the reconstruction are found in the 10th century does not mean that those were the highest temperatures over the last 2,000 years.
  49. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    All, There is new paper in press by Eastman et al. (2011) that looks at variations in cloud cover and type over the oceans between 1954 and 2008. This is one of their conclusions: "In regions of persistent MSC [marine stratus and stratocumulus clouds], time series show decreasing MSC amount. This decrease could be due to further spurious variation within the data. However, the decrease combined with observed increases in SST and the negative correlation between marine stratus and sea surface temperature suggests a positive cloud feedback to the warming sea surface." So yet more mounting observational evidence of a positive cloud feedback. And we also know from Screen and Simmonds (2010) that there is a weak positive cloud feedback operating with Arctic amplification.
  50. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    It will be interesting to see if/how Pielke responds to our question about how low climate sensitivity can gel with the paleoclimate record. As for this particular paper, it's just unfortunate that Spencer keeps trying to subvert the serious peer-review process instead of learning from it and correcting his mistakes. Had he submitted to a standard climate journal, no doubt a reviewer would have caught his cherrypick and made him correct it before publication. Then we wouldn't have gotten all the misleading media stories about his paper, and Dessler and Trenberth et al. wouldn't have had to waste time writing papers correcting his errors.

Prev  1485  1486  1487  1488  1489  1490  1491  1492  1493  1494  1495  1496  1497  1498  1499  1500  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


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