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Comments 111901 to 111950:

  1. Pakistan flood: many more will die unless more aid is delivered quickly
    "But I try not to lose sight of the fact that the reason I care about climate change is because of its impact on humanity." But if humans are causing climate change by increasing CO2 and other greenhouse gasses into the atmosphere, and we are, is it not logical that the fewer humans there are across the world, the less effect we'll have on the environment. Won't trying to save all the humans effected by 'natural' disasters, just increase the carbon footprint even more. Instead, should we not just let a natural, negative feedback mechanism do its work? Granted, losing a few million will not make much difference, but multiplying that by a few thousand 'natural' disasters will, unless we intervene by dumping even more CO2. The real question is what maximum population can support a comfortable technological level as a steady state and maintain CO2 levels, eg, at <350 ppm.
  2. Medieval Warm Period: rhetoric vs science
    Something else worth noting is that when a skeptic cites a large MWP as evidence of anything, you can always remind them that they are actually citing evidence of the Earth having a higher climate sensitivity, or warming more as a result of any given warming forcing, such as extra GHGs. That's not, I think, what they would otherwise have you believe.
  3. Medieval Warm Period: rhetoric vs science
    The Moberg reconstruction is mainly based on tree-rings. The width of tree-rings depends on the temperature, precipitation and carbon dioxide concentration, so they are unreliable to reconstruct past temperatures. The best reconstruction is Craig Loehle's, using only non-treering proxies. The fact that this reconstruction was rejected by GRL does not mean that it is a poor analysis. It only demonstrates that GRL is not yet open for paradigm breaking views like Energy and Environment is. On the basis of Loehle's reconstruction we must conclude that the medieval period very likely was hotter than today, as was the Roman period and the earlier Holocene optimum. This could mean that the effect of greenhouse gas emissions has only made a small contribution to the recent warming.
  4. Arctic Sea Ice: Why Do Skeptics Think in Only Two Dimensions?
    I'd agree with Robert's comment on using the latest data. At least you should swap the "A few days ago" to "In April 2010", so that the post remains relevant when people are reading in in weeks, months and years hence. Showing the latest PIOMAS volume anomaly data is also instructive. When the anomaly hits -13.4 in September of any year that means there's no ice left that September. This year the anomaly is currently (in August) just above -10, or off the bottom of your chart above. You can spread 6,000km^3 of ice to cover a remarkably large area of ocean, but you cannot spread 0km^3 to cover the same area...
  5. There's no empirical evidence
    Tom, The distribution of that energy, and even its form (e.g., sensible heat versus latent heat) is irrelevant to that accumulation that results from that imbalance of in versus out. Do you agree with that? Not a chance in this universe. The distribution of heat is extremely important to the overall heat of the system. And BTW - The imbalance you are talking of gets works out as quickly as nature can muster. 2nd Law. What you seem to be saying is that the imbalance only has a Radiative means to work itself out. Completely true for the entire system, however Temperature by definition is LOCAL. I've often spoke about the dangers of Averages when trying to describe a system. Where temperature is at a particular point and time is why there is such a thing as temperature. Same thing for pressure. If you averaged everything out then there is no need to measure it. Is there much more heat at the equator than at the poles? Yes, but the overall heat of the entire system is the same. Why is the heat at the equator sent mostly to space rather than to the poles? Because space is closer and colder than the poles. The average heat of our solar system is far hotter than it is here on Earth. The distribution is not only relevant, it is more important than any imbalance because it tells you where the imbalance is likely coming from. Since no one can find any flaws with 107-110 I feel safe in continuing with the availability of convection and the elasticity of the atmosphere as a mechanism to deal with the 'Imbalance' locally within the Troposphere.
  6. NASA-GISS: July 2010-- What global warming looks like
    As a followup to my previous post - if the claim is that the earth is warming, but not at unusual rates, stating that there are no reliable temperature records doesn't disprove recent fast warming; it just removes surface temperature records from the list of supportable data. In which case we're back to other evidence: Arctic melting, TOA radiative differences, growth zone movement towards the poles and increasing length of growing seasons, the physics of IR absorption tied to the ~40% increase in CO2 concentration over the last 150 years, several thousand temperature proxies, etc. - all of which indicate recent warming at unusual rates.
  7. There's no empirical evidence
    #157: "the effect of gravity and the resultant pressure play a bigger role than GHGs in accounting for this discrepancy. That is what my physics textbooks tell me." I'd suggest some new textbooks, although if you have one that mentions greenhouse gases, that's not all bad. My textbooks clearly state that PV=nRT applies to a gas in a closed system. As we said earlier, not the atmosphere. But that was your move to take this off topic. I provided some empirical evidence (Spencer); you have yet to reply to that. As far as a totalitarian scientific technocracy is concerned, I can't wait. For the rest of your rant, see the comments policy.
  8. Is the sun causing global warming?
    kamilan: "So even if the forcing was reduced, there'd be warming for potentially 90 years... Seeing as the temperature fell or remained stable while solar activity increased between 1940 and 1960, and a reduction in CO2 now would see continued warming, it suggests that temperature doesn't directly correlate (temporally) to the forcing." No it means that you appear to need some lessons in the use of language?? The words 'CO2 emissions' were used, not 'reduced atmospheric CO2'. For someone that wrote such a long comment I would expect a better understanding of issues.
  9. What caused early 20th Century warming?
    muoncounter #32 Without an equilibrium baseline TSI for the pre-industrial earth system, the magnitude of Solar forcing and energy added/subtracted over time cannot be accurately calculated. All the IPCC anthropogenic forcings from Fig 2.4 of AR4 are those of the year 2005 referenced to 1750AD. So is the 'natural' Solar forcing of 0.12W/sq.m. from that chart. As you know from elsewhere 70% of the TSI divided by 4 enters the Earth system. This implies a TSI difference of 4 x 0.12/0.7 = +0.69W/sq.m. higher in 2005 than 1750. With no other 'anthropogenic' forcings in 1750AD - and excluding volcanic effects, was the Earth warming or cooling in 1750 - or was it in 'balance'? If it was 'in balance' the equilibrium TSI should be roughly 1366.3 (TSI in 2005) minus 0.69 = 1365.6W/sq.m (TSI in 1750). My question is therefore - what is the equilibrium TSI of the Earth system with no 'anthropogenic' forcings excluding volcanic effects?
  10. Is the sun causing global warming?
    Good grief, you have a really distorted view of what I have written Eric. What I have clearly stated is that you are the problem not the science!
  11. Arctic Sea Ice: Why Do Skeptics Think in Only Two Dimensions?
    I'm thinking that this post should be revised to show the most recent data (you're missing a massive dip in ice volume) and WUWT is no longer arguing we are recovering but just that it won't be the least on record. An interesting link to see is here: http://arctic.atmos.uiuc.edu/cryosphere/NEWIMAGES/arctic.seaice.color.000.png The Northwest passage is officially open.
  12. Medieval Warm Period: rhetoric vs science
    Woops, I misread humanity Rules statement. I apologize for making an incorrect response. But my findings are still robust I think. Most have argued the NH was warmer during the MWP than the SH. Therefore the most important relevance is showing the NH temps now are above (which they are). SH is not irrelevant but is not as important in this particular argument.
  13. Medieval Warm Period: rhetoric vs science
    First of All, you cite a non-peer-reviewed article to illustrate your Grand Maximum theory. If this were in fact the case and we were currently in a grand maximum that explains climate change then I am sure that the authors will be publishing their results in a reputable journal. Perhaps journal of climate, nature geoscience, science, GRL, international journal of climatology, climatic changes, climate dynamics…etc… rather than the 1st issue of a solar magazine for solar enthusiasts including amateurs (as indicated by the website). Secondly, I understand there are different cycles which operate within the system and can likely explain some of the current warming. Viau et al. 2006 very much talks about this and shows a 1050 year cycle which can explain some of the warming. The conclusions though, are that those very same cycles CANNOT explain the amount of late 20th century warmth and can at the most explain 0.2-0.3 °C of the 0.8 °C warming. Thirdly, Most of Antarctica is not cooling. See Steig et al. 2009. Most is in fact warming. Fourthly, the MWP in the NH was not much warmer than today. Moburg et al. 2006, Viau et al. 2006, Mann et al. 2008, Mann et al. 2009, Kaufmann et al. 2009, and D’Arrigo et al. 2006. Lets see a peer-reviewed regional reconstruction which does not show warmer temperatures in NH late 20th century than during the MWP? Loehle 2008? Energy and Environment is not a real peer-review journal. GRL rejected his analysis immediately realizing it was poor quality. In summary, there are no hemisphere wide reconstructions which show greater warm. And even local reconstructions in many areas show that the MWP has been surpassed. Buntgen et al. 2008 is a good study for that which shows the European alps much warmer now (Tree-rings don’t diverge till after 2004 making it a landmark study). Fifth point, When the models overestimate warming then it can’t be GHG but when they underestimate then it can’t be GHG either? Lets be honest, you’re just a contrarian who will take any evidence you can and try and find a way to massage it to fit your idea that AGW is a fraud. Finally, No one argues there aren’t natural contributions. You can find it quite clearly on this website. The important delineation is that we have empirical evidence for an enhanced greenhouse effect. Until you can disprove physics and direct measurements you have no case. http://www.skepticalscience.com/Empirical-evidence-that-humans-are-causing-global-warming.html
  14. NASA-GISS: July 2010-- What global warming looks like
    Pete Ridley - I find the juxtaposition of your two statements, "Nowhere in that comment to which you link have I said that global warming, ice cap melting or ocean acidification isn’t happening" and in the same post "There is clearly no basis for the claims that the Earth has warmed at unusual rates in recent times...", clearly contradictory. No basis for claims that the Earth is warming at unusual rates? But not claiming that global warming isn't happening? I suspect I'm not the only person who sees a conflict there.
  15. Medieval Warm Period: rhetoric vs science
    Robert Way writes: For the record also, notice many of these are hemispheric reconstructions and i'm sure you are mistaken in saying 6 points were used for a recent global reconstruction. I think HumanityRules was specifically referring to the southern hemisphere ("... as little as 6 data point for the whole of the SH ...").
  16. Pakistan flood: many more will die unless more aid is delivered quickly
    Adelady, I agree with you, climatologists of all people should understand the trouble ahead for humanity. A carefully considered response to reinforce the message that these extremes will become common place in the not too distant future, will at least be a step in the right direction.
  17. Medieval Warm Period: rhetoric vs science
    Humanity Rules, You're building strawmen. No one says that oceans circulation changes cannot be contributing to current warming. The dominant forcing is CO2 and the secondary forcing today is the AMO. Who says that ALL warming is caused by CO2 and that there aren't natural contributors? Which reconstructions are the best? Personally I think Moburg et al. 2005 is the best. I've seen quite a bit of evidence to support this theory including Moburg (2008). The thermometer is valid at the end, proxies are calibrated against the thermometer in order to decide which ones to use. If you can calibrate against one then you are essentially saying that only proxies which correlate well with the instrumental record are being selected, thereby making it an appropriate choice. For the record also, Moburg et al. 2005 does not rely on 6 proxies and neither does Mann et al. 2008 or Mann et al. 2009 or Mann et al. 2003 or D'Arrigo et al. 2006 or Viau et al. 2006, or Kaufman et al. 2009. So perhaps it is best that you not regurgitate common skeptic arguments that are completely flawed ok? For the record also, notice many of these are hemispheric reconstructions and i'm sure you are mistaken in saying 6 points were used for a recent global reconstruction. You should consider keeping things to yourself if you are going to make clear errors in what you say.
  18. Can't We At Least Agree That There Is No Consensus?
    Poptech wrote : "Pielke Jr. has never asked for anything to b removed, which is irrelevant as his papers were never submitted to the list so he cannot have them removed. Regardless is papers are not listed based on his original misunderstanding." Convoluted (and confused), or what ? Let's break that paragraph down : "Pielke Jr. has never asked for anything to b removed..." Um, yes he did : you just keep ignoring his words here : A quick count shows that they have 21 papers on the list by me and/or my father. Assuming that these are Hypothesis 1 type bloggers they'd better change that to 429 papers, as their list doesn't represent what they think it does. Roger Pielke Jr's Blog - Better recheck that list Then again, going by the next part of your paragraph, you DID notice his words but chose to ignore them, when you write : ...which is irrelevant as his papers were never submitted to the list so he cannot have them removed." So, he DID ask for his papers to be removed but you think his request is "irrelevant" because he didn't submit them in the first place and you have decided that they are staying, no matter what the original author thinks. And, in fact, Pielke Jnr did show you how you could possibly square the circle of using papers that should not be used the in the way you believe they can be used : There is nothing in my writing that fits in this category. If they sopport _your_ skepticism then I suggest retitling the post to be: "450 Peer-Reviewed Papers Supporting My Skepticism of "Man-Made" Global Warming" Roger Pielke Jr's Blog - Better recheck that list I'd suggest then that you clarify your post and its title to more accurately reflect what it purports to show. Roger Pielke Jr's Blog - Better recheck that list That would then give you the right to use papers in any strange way you wish to, even if the original authors don't agree with the way their papers are being used - you can then tell them that it is YOUR opinion of what their papers are about, to back up YOUR version of skepticism. Why don't you change the title yet again, so it better represents real-world reality ? But, in the end, you believe you know best and believe you have explained the rationale behind your little list (even though that wasn't agreed by Pielke Jnr) when you assert : "Regardless is papers are not listed based on his original misunderstanding." So, even though Pielke DID ask for his papers to be removed but you think that his request was "irrelevant" (according to your own strange criteria), you are going to disregard everything because he doesn't seem to realise what it is you are trying to do by using his papers. Well, does anyone but you know what your little list represents ? I very much doubt it.
  19. Medieval Warm Period: rhetoric vs science
    HumanityRules writes: That in-filling is dependant on the theories that support AGW. Can you explain what you mean by that? As far as I can tell, the questions of whether N proxies are sufficient for a hemispherical temperature reconstruction, and how best to spatially weight those N proxies, are mostly statistical in nature. How exactly is the interpolation or weighting of proxies "dependent on the theories that support AGW"? Which theories? Also, could you cite what you're referring to as "the best multi-proxy reconstructions"?
  20. Pakistan flood: many more will die unless more aid is delivered quickly
    Lou, My feeling is that experts need to *first* say that soemthing is or is not consistent with expectations. Both you and I want to say something more about the dangers, but experts also have to avoid being seen as doomsayers. Saying we need time for the science was really my strategy for getting reporters off the back pronto, rather than getting into long-winded explanations of statistical esoterica. Because we know where that can finish up.
  21. Medieval Warm Period: rhetoric vs science
    On your first point. How do we get a global average temp for the MWP when the best multi-proxy reconstructions reply on as little as 6 data point for the whole of the SH at that time? There has to be a huge level of in-filling. That in-filling is dependant on the theories that support AGW. Secondly, I've read articles recently that suggest again that much of the high latitude NH warming is again due to ocean circulation. What's wrong with accepting this as part of the picture today? Fianlly I'm still unconvinced that pasting the thermometer record on the end of a proxy reconstruction is totally valid. I agree it's very appealing but is it valid?
  22. Anne-Marie Blackburn at 22:02 PM on 23 August 2010
    Pakistan flood: many more will die unless more aid is delivered quickly
    I think it's wrong to say that these extreme events are caused by climate change. But it's equally wrong to say that climate change isn't in all likelihood contributing to the severity of these events. But back to the original post, keep giving because the scale of this crisis is huge.
  23. Pakistan flood: many more will die unless more aid is delivered quickly
    "This is exactly the kind of thing we expect with climate disruption. We'll need a few months to analyse whether this particular event is in that category". Distortion of facts again. The fact is that the Pakistan floods are the result of an unusual but not unheard of weather event, along with the China floods, Western Russia drought and other global catastrophes cause by weather events. As someone who has far more expertise about weather than anyone here says in the Climate Realist article “Breaking - Russian heat wave due to dramatic changes in solar activity – Interview with forecaster Piers Corbyn” (Note 1) QUOTE: This year Russia was hit by a record-breaking heat wave that led to wildfires which killed dozens and left thousands homeless. Weather forecaster Piers Corbyn says this is a result of weather cycles, not global warming. “What we have is a tremendous amount of activity on the sun and that affects the rush of particles from the sun to the earth and that changes the ionosphere and that also changes the circulation patterns of the globe in what is known as the jet stream,” Corbyn explained. “And that caused a shifting of the weather patterns so the south wind in Western Russia terminated and instead we got a northwestern flow of thunderstorms and cooling” UNQUOTE. NOTES: 1) see http://climaterealists.com/?id=6173 Best regards, Pete Ridley
  24. NASA-GISS: July 2010-- What global warming looks like
    KR, ref. your comments at 05.22 and 05:51 on 20th, please stop distorting what I say. I know it’s a popular tactic with supporters of The (significant human-made global climate change) Hypothesis but it simply undermines your credibility when you can’t back up what you claim. Nowhere in that comment to which you link have I said that global warming, ice cap melting or ocean acidification isn’t happening. Even the comments of John O’Sullivan and Charles Anderson which I quote do not say that. What is said is quite different and is perfectly expressed in the final sentence of the final quote “It is now perfectly clear that there are no reliable worldwide temperature records and that we have little more than anecdotal information on the temperature history of the Earth. There is clearly no basis for the claims that the Earth has warmed at unusual rates in recent times or that we know anything more than some local temperatures, mostly from urban heat effect zones”. Doug, my response to your comment has been removed to I've posted on the new thread “Pakistan Flood: Many More Will Die .. ” Best regards, Pete ridley
  25. Pakistan flood: many more will die unless more aid is delivered quickly
    adelady: "This is exactly the kind of thing we expect with climate disruption. We'll need a few months to analyse whether this particular event is in that category." I agree completely with the first sentence, but what does the second one mean? In what category? The response just said it was the kind we'll see more of with further disruption, so what's left to decide that could be determined in "a few months"? Surely you're not saying that in a few months scientists would be able to determine if AGW definitively caused any given event. I would keep the first sentence you propose and change the second to something like, "If we continue to pour 30 billion tons of CO2 into the air every year then tragedies like this will happen more and more often." And yes, everyone needs to donate. I made a similar plea on my site yesterday (http://www.grinzo.com/energy/index.php/2010/08/22/helping-and-learning-from-pakistan/), and I even linked to the same articles John did.
  26. Arkadiusz Semczyszak at 20:31 PM on 23 August 2010
    Medieval Warm Period: rhetoric vs science
    Agreed. For the current warming cycle is likely to correspond to 2.5 thousand. years, + 4.2 thousand years, maybe six thousand. years. MWP is only responsible for a cycles of Millennium. see here. The current solar activity is the Grand Maximum - Solar cycle variations on the millennial times scale: a challenge for solar dynamo theory, Usoskin, 2010.. The MWP in NH, however, was much warmer than today. The logical conclusion: still waiting for us so much bigger natural warming, than is now and was in the MCA. Currently, the Earth is getting warmer just unevenly - as in the MWP - as usually happens in the Millennium cycles: Most of Antarctica is cooling, like for example central and N. China ( Characteristics of cold–warm variation in the Hetao region and its surrounding areas in China during the past 5000 years, Li, 2010.), Fennoskandia (Grud, 2008.), and Western Europe is warming much faster than expected.): “The MODEL [including anthropogenic GHG] simulates a factor 1.24±0.09 faster warming than the global mean, but the OBSERVATIONS have a trend A=2.50 ± 0.39.” This is 0.75 (global) to 0.94 deg. C (W. E.) in secular scale. IPCC report: “The Working Group I (WGI) WGI FAR noted that past climates could provide analogues. Fifteen years of research since that assessment has identified a range of variations and instabilities in the climate system that occurred during the last 2 Myr of glacial-interglacial cycles and in the super-warm period of 50 Ma. These past climates do not appear to be analogues of the immediate future, yet they do reveal a wide range of climate processes that need to be understood when projecting 21st-century climate change ...”
  27. Pakistan flood: many more will die unless more aid is delivered quickly
    Everybody needs to donate. Unfortunately the aid and international coordinating organisations need to restructure around the likelihood of more than one international scale catastrophe per year. And climate scientists need to learn the right reaction when a microphone is shoved under the nose... "Is this due to global warming?" "This is exactly the kind of thing we expect with climate disruption. We'll need a few months to analyse whether this particular event is in that category." State the possibility first. Emphasise the need for more science to be accurate.
  28. Eric (skeptic) at 19:52 PM on 23 August 2010
    Weather vs Climate: Watch the waves, miss the turning of the tides
    Your first point may be valid. ON the second, AFAIK, satellites don't measure record temperatures, just averages. If you have a study showing otherwise, please post it. Averages on the surface are adjusted for UHIE, records are not. On 1998, the state record high temperatures peaked at 19 ( http://hallofrecord.blogspot.com/2007/03/us-extreme-temperatures-update.html) Since state records are often set at smaller stations, they are more immune to UHIE. Hence there are far more standing state records from the 1930's than any other decade.
  29. The main culprit in mid-century cooling
    Ok and thanks Michael
  30. Arkadiusz Semczyszak at 18:25 PM on 23 August 2010
    Dust-Up On Mars: Should Martians Be Sceptical of Global Warming?
    The Cosmology of Climate Change: Intercorrelations Between Increased Global Temperature, Carbon Dioxide and Geomagnetic Activity, Persinger, 2010.: “Recent global warming is correlated strongly with not only levels of carbon dioxide but also increased geomagnetic activity.” “The apparent relationship to human activity would be epiphenomenal.” “The correlations between recent insidious elevations in global temperature and green house gases, which include water vapour as well as carbon dioxide, have been attributed in large part after the year 1945 to the behaviour of human beings (NAS 2010a,b,c; Tett et al, 1999). However concomitant with the increased magnitudes for human activity since about the year 1900 there has been a doubling of the solar corona (Lockwood, et al, 1999) and a gradual increase in average geomagnetic activity (Persinger, 2009a). A similar increase in global temperature has been observed recently within a more restricted time frame on MARS (Fenton et al, 2007) which is presumably independent of anthropogenic activities.” “Correlations are not necessarily causations. For problems that are not amenable to the benefits of direct experimentation, the presence of other factors that are responsible for the occurrence of both variables that constitute the correlation must always be considered. These include changes in solar activity, alterations in the angle and orbit of Earth (Duhau and Jager 2010; Miyahara et al., 2010) and fluctuations in geomagnetic activity. Both El-Borie and Al-Thoyaib (2006) and Persinger (2009a) have shown that at least half of the variance in the global warming can be accommodated by the energy available from the upward drift in geomagnetic activity. That these factors associated with solar activity have been responsible for the epiphenomenal relationship between global warming, human activity and the concomitant increases in green house gases, would affect both humanity's approach to the solutions as well as the focus in the search for mechanisms.” I recommend this paper: Solar cycle variations on the millennial times scale: a challenge for solar dynamo theory, Usoskin, 2010.; ... and two conclusions of the multimedia presentation: Grand Minima and Maxima of Solar Activity on multi-millennial time scale (Usoskin, Solanki, Kovaltsov, 2010): - The Sun spends ~3/4 of the time at moderate activity, ~1/6 in a grand minimum and ~1/10 in a grand maximum state. The modern solar activity is a grand maximum., - Occurrence of Grand minima/maxima is not a result of long-term cyclic variations but is defined by stochastic / chaotic processes (Suess/de Vries cycle may operate at a shorter scale). ... and from this work: The Sun's role in regulating Earth's climate dynamics, Mackey, 2009.: “Climate processes are interconnected and oscillating, yielding variable periodicities. Solar processes, especially when interacting, amplify or dampen these periodicities producing distinctive climatic cycles. As solar and climate processes are non-linear, non-stationary and non-ergodic, appropriate analytic methodologies are necessary to reveal satisfactorily solar/climate relationships.” Warming on Mars must therefore be real and be a result of a complex (including magnetic) solar activity (f. e .QBO).
  31. Medieval Warm Period: rhetoric vs science
    The IPCC describes our level of scientific understanding of the pre-1978 solar activity data as “very low”. (Graph and comments at Here comes the sun ). Crowley (2000) is a paper matching modeled results with solar activity estimates derived from Lean et al (1995) and Bard et al (2000). It's not a paper validating solar output (except by matching model results). Bard (2000) says "The concomitant production variations of 14C and 10Be can be used as a proxy for the TSI by assuming a linear relationship between magnetic activity and irradiance following previous workers.." and notes the familiar sunspot papers including Solanski and Fligge. This S&F paper notes that their sunspot relationships *assumes* the measured relationship between sunspots and output over 20 years is then matched for the previous 100. It's nice to assume a relationship and I think it's a good starting point given no other information. However, that doesn't mean it has been validated. Which is why the IPCC says that results back to 1600 "have a low level of scientific understanding" and claims less certainty before that..
  32. The main culprit in mid-century cooling
    What happened to the link ? My comment #7 doesn't make sense without the link http://www.spinonthat.com/CO2.html
    Response: Well, your comment does make more sense now that you've posted that link which wasn't included in the initial comment. And yes, now I see that your comment is off-topic :-)

    To discuss whether there's a greenhouse effect, I suggest you either go to the empirical evidence for the enhanced greenhouse effect or Has the greenhouse effect been falsified?.
  33. Medieval Warm Period: rhetoric vs science
    stevecarsonr, The Medieval Maximum of solar activity occurred during the MWP. This has been discussed in numerous papers. Some I just threw together in the last few minutes for your comment are below. There are many more. Also note that although we don't have year to year changes very effectively measured back as far as the MWP we do have many paleoclimatic proxies which give evidence suggesting a solar maximum. Ultimately the MWP can be viewed very similarly to an extended 1940s era warming. Tyson, P.D., Karlen, W., Holmgren, K. and Heiss, G.A. 2000. The Little Ice Age and medieval warming in South Africa. South African Journal of Science 96: 121-126. 30. Beryllium-10 measurements are from E. Bard et al., Earth Planet. Sci. Lett. 150, 453 (1997); E. Bard et al., Tellus B 52, 985 (2000). 31. M. Stuiver and T. F. Braziunas, Radiocarbon 35, 137 (1993). Crowley 2000. Science. Causes of Climate Change over the Past 1000 years. Jirikowic and Damon. (1994). The medieval solar activity maximum. Climatic change. Volume 26, Numbers 2-3.
  34. The main culprit in mid-century cooling
    I'm not sure if this is on topic, but I feel it is pertinent to AGW. Does this experiment prove that CO2 is not a greenhouse gas? And if not, why not? Michael
    Response: Does this experiment prove that CO2 is not a greenhouse gas? And if not, why not?

    On the contrary, the behaviour of temperatures during the mid-century cooling period actually confirm the greenhouse warming effect. What we find is that daytime temperatures cooled from the 1940s to the 1970s. This is consistent with measurements of solar radiation at the Earth's surface which also fell over this period - "global dimming" due to rising sulfate pollution. But interestingly, nighttime temperatures actually increased over this same period. This is consistent with an increasing greenhouse effect. Even while sulfate pollution was cooling the Earth, greenhouse warming was still percolating away while we were sleeping.
  35. Medieval Warm Period: rhetoric vs science
    "It has now become clear to scientists that the Medieval Warm Period occurred during a time which had higher than average solar radiation and less volcanic activity (both resulting in warming)" Can you elaborate on the first one? As far as I can see reconstructions of solar radiation prior to 1978 are speculative. This even goes for the reconstructions from 1874 when high quality sunspot observations began. For example, Solanske & Fligge commented that their sunspot reconstruction relied on the assumption that the measured relationships have remained unchanged over more than a century - "Solar Irradiance since 1874 Revisited", Solanski & Fligge, Geophysical Research Letters (1998).
  36. There's no empirical evidence
    AWoL - sadly you cannot take a high school equation useful within its domain and then use it inappropriately somewhere else. If you want to understand it depth (you do dont you?), then I suggested the Science of Doom article with goes through it in depth. Also this . If this is going to come up often, then perhaps John should get Chris Colose to right up the argument.
  37. Medieval Warm Period: rhetoric vs science
    WAG, that'd be perhaps better addressed in the rebuttal of the "It's not bad" argument. Although perhaps a comment pointing readers to that argument would be useful in here.
  38. Medieval Warm Period: rhetoric vs science
    Good post. One comment - I think the real reason skeptics make this argument is to argue that if it was warmer in Medieval times than it is now, then global warming must not be bad - not to argue that it isn't caused by people. An answer to that claim ought to be included as well.
  39. There's no empirical evidence
    Muoncounter. If you think this has gone wildly off topic then you have only yourself to blame. You made the claim that the 33deg C difference between the black body calculation and the actual earth surface temp was due to greenhouse gases. I say no, and that the effect of gravity and the resultant pressure play a bigger role than GHGs in accounting for this discrepancy. That is what my physics textbooks tell me. If I am wrong tell me why. If you can't be bothered, then let's not waste time in discussion, and we'll forget about science and the enlightenment, freedom of speech, and thought, and simply cough up a 5% carbon tax and quiescently submit to the rule of totalitarian scientific technocracy and live happily ever after.
  40. Philippe Chantreau at 11:47 AM on 23 August 2010
    The Good, The Bad and The Ugly Effects of Climate Change
    Thread is cold but this paper looks interesting and relevant http://www.sciencemag.org/cgi/content/abstract/329/5994/940
  41. There's no empirical evidence
    AWoL - yes Science of Doom prejudices are very obvious. He is extremely in favour of textbook physics. As is John Cook for that matter so why are you here? Would you only accept physics if it is explained by an anti-AGW physicist? Not many around but I would be comfortable say Roy Spencer on this pressure nonsense. His take down of Miskolczi and G&T are fine. Has he talked about it? There is a "information trust" problem that really makes me scratch my head. When you dont have the expertise to make an assessment yourself, then who do believe? Physicists - or Steve Goddard?
  42. Can't We At Least Agree That There Is No Consensus?
    Who introduced the word 'consensus' in science?
  43. There's no empirical evidence
    #153: "what must the Temp be at 15lbs/squ in?" Its not a closed system, so the temperature will, as you say, 'equilibrate with surroundings.' Or else we'd only have hot days with high pressure and cold days with low pressure, which would take all the fun out of weather forecasting. This is becoming wildly off-topic.
  44. There's no empirical evidence
    #152: "nature had already put in place processes that must have not only controlled the rate of loss, but the rate of gain. " And then we came along and starting releasing all that CO2 that was stored away for millions of years... in the last 150+ years. How do you think nature 'reacts' to that? Seems like the answer is right in front of us.
  45. There's no empirical evidence
    I take the points of Muoncounter and Tom. Yes the temperature of a compressed gas will equilibrate with the surroundings. Nevertheless we are starting from TOA of Odeg and near 0 pressure....BUT.... that temperature is 0deg,273K, thanks to insolation, otherwise it would be 3K or thereabouts. So that being the case, what must the Temp be at 15lbs/squ in?(at the surface)? I have visited the Science of Doom a few times, but the prejudices of the author are very obvious. Why in this age of computerisation of graphics is this medium so seldom employed? One picture is worth a thousand words,mind you it depends on the quality of the picture.
  46. There's no empirical evidence
    Tom Dayton at 06:41 AM, unlike the heat temporarily "trapped" in the bicycle tube, heat within our atmosphere has not been physically constrained as the usage of the word "trapped" by some posters seems to indicate. No heat is actually trapped, heat is always being lost, as heat is always being gained. What does change is the rate at which it is either gained or lost by the atmosphere, and it is how that balances out that determines whether the temperature is warming or cooling. This balance, if able to be controlled by man would either have to control the rate of loss, or the rate of gain. Before mankind arrived nature had already put in place processes that must have not only controlled the rate of loss, but the rate of gain. If variations in solar radiation was the sole means by which the rate of gain varied, what were the processes that adjusted the rate of loss?
  47. What were climate scientists predicting in the 1970s?
    Here's a couple of snips from an interesting paper, with predictions made in 1981: I've added the red lines showing where we are now, about 0.6 deg in the upper figure (Fig 1, which starts in 1880) and 0.5 deg in the lower (starts in 1950). Looks like whoever made those predictions was spot on in Fig 1, but a bit conservative in Fig 7. However, we are well above the 'natural climate variability noise,' so you gotta give it some credit. The paper? Climate impact of increasing atmospheric carbon dioxide. Check the link to see the authors.
    Response: NOTE: after reading this comment, I asked Muoncounter if he would do a blog post about Hansen's 1981 paper - he kindly obliged in Hansen etal hit a Climate Home Run.
  48. Weather vs Climate: Watch the waves, miss the turning of the tides
    #5: "records are usually 5C to 10C or more above normal so are caused by weather, not CO2 warming" This is a persistent pattern of setting records and hence not weather. Long term trend... increasing CO2? "records in the chart above were not adjusted for UHIE" We've heard that one numerous times. Satellite data show similar temperatures; is there also UHI in satellite data? "too easily influenced by pacific ocean cycles" If ocean cycles were a factor, 1998 would stand out like a sore thumb. Yet it is part of the whole. So that 'problem' won't fly either.
  49. There's no empirical evidence
    I'd like to point out that SoD's The Hoover Incident provides a delightful Reductio ad absurdum argument supporting the greenhouse gas effect - demonstrating that current conditions cannot hold without the greenhouse effect, and that asserting GHG's have no effect results in a contradiction (temperatures that are not currently observed, an average temperature of -18°C; brrrr....).
  50. Eric (skeptic) at 06:42 AM on 23 August 2010
    Weather vs Climate: Watch the waves, miss the turning of the tides
    The first problem is that records are usually 5C to 10C or more above normal so are caused by weather, not CO2 warming (1C with WV, 0.2 or so without). The second problem is that the records in the chart above were not adjusted for UHIE (it was not mentioned in the paper). Third problem is the chart is U.S. only, too easily influenced by pacific ocean cycles which can result in extremes.

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