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Comments 69951 to 70000:

  1. The Debunking Handbook Part 1: The first myth about debunking
    As alan_marshall #1 said!
  2. Philippe Chantreau at 19:06 PM on 17 November 2011
    World Energy Outlook 2011: “The door to 2°C is closing”
    I will add that I am no advocate for biofuels, which do not make sense in their current schemes of production, from a carbon budget point of view. Large agri-businesses are the main actors pushing these fuels. they are carbon inensive in their production that they do not present any significant advantage.
  3. Philippe Chantreau at 19:01 PM on 17 November 2011
    World Energy Outlook 2011: “The door to 2°C is closing”
    I understand what your point was skept; however, it should have been worded rather as "may have participated in" since, as you pointed yourself, some research failed to find any evidence tha it actually did. As is stands now, there is no single greater threat to the World economy than speculation and the behaviors of the major actors in the economy. As a risk, speculation dwarfs the effect of any possible climate mitigation policy by orders of magnitude. It is bad behavior, wishful thinking and speculation that brought the current crisis, costing literally trillions. I'm sure you'll then understand that I'm unimpressed by a problem that has not been showed to be significant, let alone exist at all. I would take the economic concerns of skeptics more seriously if they were ever ready to address, or even acknowledge the real economic problems, the kind that can demonstrably cause a crisis like the current one.
  4. The Last Interglacial Part Five - A Crystal Ball?
    5, skept.fr, ClimateWatcher's references to the Eemian and Holocene were a throwaway statement intended to let him say anything he wanted without seeming to be off-topic. His real intent was to carry forth the lame denier meme that since summer/winter temperatures/insolation vary so greatly within each year that CO2 variations must be comparatively negligible.
  5. Extreme Events Increase With Global Warming
    Norman#61: First of all, quoting a smattering of links is hardly deserving of the term 'research.' Second: Your NASA link on blocking? Stalled Weather Systems More Frequent in Decades of Warmer Atlantic The researchers observed the frequency of blocked weather events in the North Atlantic ... over the entire twentieth century and compared it to the evolution of ocean surface temperatures for the same area. They then removed the effect that global warming has on water temperatures, and found that decades with more frequent, recurring blocking events in the North Atlantic corresponded to those decades when the North Atlantic Ocean was warmer than usual, as it is now. Nothing there about global warming - by design. Your 'Abstract describes': Winters with clusters of more frequent blocking between Greenland and western Europe correspond to a warmer, more saline subpolar ocean. It's not clear from that whether blocking causes warming or warming causes blocking.
  6. Extreme Events Increase With Global Warming
    "If the blocking patterns remain the same with global warming, I see no logical reason to assume more extreme heat waves (greater frequency)." Norman, your final paragraph in #61 seems to explain where you are going wrong. You seem unable to understand what happens when you shift a Gaussian distribution to the right. Tom Curtis in #61 does a good job in trying to explain. You do realise that the graphs in Hansen et al 2011, posted by muoncounter in #30, directly contradict your above claim, and that these are observations?
  7. Extreme Events Increase With Global Warming
    muoncounter @58 and DB, Here are some of the sources of the blocking patterns argument. First comes from skywatcher's post 44 on the "Review of Rough Winds: Extreme Weather and Climate Change by James Powell" In Stu Ostro's presentation he shows how extreme weather is caused by numerous blocking patterns. skywatcher link in post 44. NASA research on blocking patterns. Old article on blocking patterns. abstract describes how blocking can lead to warming. blocking patterns. Tony Lupo to study blocking. There are many others all saying close to the same thing. Blocking patterns create much of the extreme weather we experience. Heat, cold, snow, rain (in the extreme). My point is not that absurd or farfetched and it seems all who study the phenomena are in agreement as to what it will do to regional weather. If it can be demonstrated that global warming increases blocking patterns, then it would logically follow that global warming will result in more weather extreme events. Otherwise it would just be factual that global warming will raise the avearge temperature and make things warmer. If the blocking patterns remain the same with global warming, I see no logical reason to assume more extreme heat waves (greater frequency). I would agree that the heat waves that do occur will be warmer (by a few degrees) than similar heat waves in the past.
  8. Extreme Events Increase With Global Warming
    Norman @48 and @55, you appear to working under several misconceptions. First, nobody is denying that meteorological, and major climactic events have the dominant role in day to day weather. There is a drought in Texas because of a La Nina event. There was a heat wave in Moscow because of a blocking event. Trivially, the probability of exactly identical heatwaves of blocking events occurring at exactly the same time without greenhouse gas forcing is almost zero (butterfly effect); but almost as trivially and far more importantly, La Nina's and blocking events would have occurred at very similar frequencies in the absence of GHG forcings. What is being claimed is that global warming influences the events that occur so that very high temperatures become more common than they once where. Second, you can approximate to the effect of global warming by simply adding the monthly value of the trend in global warming to the monthly or daily temperatures. This is a very crude approximation, but it does not lead you totally astray. Based on that, for example, John Nielsen-Gammon (state climatologist for Texas) argues that:
    "This record-setting summer was 5.4 F above average. The lack of precipitation accounts for 4.0 F, greenhouse gases global warming [edited 9/11/11] accounts for another 0.9 F, and the AMO accounts for another 0.3 F. Note that there’s uncertainty with all those numbers, and I have only made the crudest attempts at quantifying the uncertainty. But this will do until something better comes along."
    I would quibble that the drought was partly the result of the heat, so that some of the "drought contribution" is a secondary effect of global warming. But Neilsen=Gammon's position is perfectly reasonable. You could also as a crude model simply add the regional global warming anomaly to the Russian heatwave and say that that was the contribution of global warming. That contribution is not 0.8 degrees C, ie, the global anomaly, but closer to 1.8 degrees C (four decades of the decadal trend) for the Moscow region). But using the correct figures, the approach is not unreasonable. Using that approach, you would say that global warming added 1.8 C to the 6.67 degree C July 2010 Moscow anomaly, or 27%. However, leaving the analysis there seriously underestimates the effect of global warming on the return frequency of extreme events. For example, even a 0.8 degree C increase in mean temperatures represents a significant fraction of a Standard Deviation. For high Standard Deviation events such as those in the US in 1936 or Moscow in 2010, even a small increase in temperature can greatly increase the return interval. As an example of this, your state SD of the Bismarck record was 5, whereas, the actual value was 4.89. That 0.11 difference in SD increases the return interval by more than 70%. That is, a 0.67 degree C increase in temperature can increase the return inverval from 32,000 years to 56,000 years assuming normal distribution. For actual values found such as the Moscow event, the return interval can be increased from 1 in 260 year events to 1 in 1000 year events just by that small difference in temperature. Hence, using this crude model, the only logical conclusion is that global warming significantly reduces the return period of extreme temperature events. Finally, and briefly, it is not at all clear that the crude model is in fact warranted. There is evidence that global warming is changing the frequency and intensity of ENSO episodes (although the evidence is not conclusive). There are good logical reason to expect a non-stationary climate, ie, one significantly warming over time, to not be as well behaved as a stationary climate. These are areas around which there is legitimate debate. But without venturing into those areas, the conclusion you are arguing against follows directly from your own premises. And a final note about your 52, despite the many records set in the state, the map you show (as also the one from GISS) shows the highly localized nature of the very extreme heat. Further, I'll see your 17 states from 1936 and raise you 19 national records from 2010.
    Response:

    [DB] Fixed html issues.

  9. Extreme Events Increase With Global Warming
    Norman, please, please go look at the Hansen graph that muoncounter linked to in #30. It demolishes your statement in #55, and I really would like you to understand that. The 'modest' global warming we have experienced has greatly increased the chances of seeing a 'hot' or 'extremely hot' spell of weather. That's not projected, that is from observations. We should hope that blocking patterns (whatever your 'research') don't materially increase in a warming world - Hansen's and R & C's work show that the increasing number of extremes needs no help...
  10. Extreme Events Increase With Global Warming
    Norman#55: "The research I have done on the topic still indicates ... " OK, out with it. Trenberth, tamino, Hansen, R and C have all put their work on the table. Call: What cards do you have, other than your Bismarck ace-in-the-hole?
  11. Extreme Events Increase With Global Warming
    Norman#48: "the current amount of global warming would only increase the average a few degrees." Well, that's a start; despite the fact that it reveals a very basic misconception. The key word in that statement is global. Increasing the global - or even hemispheric - average temperature by 'a few degrees' is a lot of warming. But your fascination for individual location, short term records is more of the same 'I can't see it, so its not happening.' How does one month in Bismarck, ND equate to all of Europe showing a significant increase in the number of summer days much warmer than a 30 year average? The graphs here include your 1936 heat wave. At that time, approx 40% of the NH land area saw summers classified as 'hot' and very little area was classed as 'extremely hot.' Now we see approx 80% 'hot' and nearly 20% 'extremely hot.' What happened in Bismarck this past summer is just a tiny spot out of that land area. How can you continue to miss this point?
  12. Extreme Events Increase With Global Warming
    Norman @50, the data source you link to is just the daily temperatures for July 2011. That is a small data set, and distorted high by global warming. More importantly, it is a daily mean. The July 2010 temperature often quoted for Moscow was a monthly average. That means while, assuming a normal distribution and no global warming, the probability of a Moscow 2010 heat wave is only 1 in 66,667 in a given year, the probability of a Bismarck maximum under the same assumptions, and using your data is only one in every 32,258 years. Of course, temperature records are not normally distributed. Accounting for that, and for global warming, Tamino shows that the average return interval of a Moscow style heat wave is 260 years given the current level of global warming, or close to 1 in every 1000 years without global warming. (Note that that makes the event 4 times more likely based on global warming, an independent confirmation of Rahmstorf and Comou.) The correct estimate of the temperature record for Bismarck requires a similar detailed analysis to that provided by Tamino, using more than a single months data. One thing we can be sure of, however, is that the result will (once again) show the event to be significantly more probable than the Moscow event. Finally, you still appear to be arguing that because you can role a '12' on a pair of standard dice, that shows you will not role '12's more frequently if you use a standard die, and a second die numbered '2' to '7'. Such an argument is a game effort in denialism, but is doomed to failure for anyone prepared to look at the data logically.
  13. Extreme Events Increase With Global Warming
    Rob Painting @53 Yes that is true, the cold extremes would diminish and the warm extremes would increase. I agree with this logical thought process. As I look at Figure 1 from you above original post, I know the current global warming is about 0.8 C. This would shift the distribution curve just slightly to the right. Not enough to really affect the 2010 Moscow anomaly either way or make it more likely. If the model projections for global warming are correct with a large temp increase (due to possibility of enhanced effects...doubling CO2 levels by themselves will only raise the global temp a couple of degrees) then the shift will definately make 2010 events much more likely as they become normal events. The research I have done on the topic still indicates that blocking patterns caused this heat wave and the pattern would have taken place regardless of warming.
    Response:

    [DB] "Not enough to really affect the 2010 Moscow anomaly either way or make it more likely."

    Based on what citation do you state this so authoritatively?

    "The research I have done on the topic still indicates that blocking patterns caused this heat wave and the pattern would have taken place regardless of warming."

    Then feel free to submit that research for publication in a reputable journal.  In the meantime, you continue to prosecute your agenda of selective cherry-picking & disregarding all evidence that doesn't conform to your preset view of things.

    Shorter response: you continue to waste the time of others here.  For now.  This will not last, however...

  14. Extreme Events Increase With Global Warming
    Norman, the question you are failing to answer is this: Why does the existence of any past individual event change anything about the increasing probability of extremes in a warming world? Your #50 is irrelevant - all it shows is that in the map for 1936 a la Hansen et al 2011, North Dakota would have experienced a >= 3-sigma event and been coloured brown. Otto would have had a hot summer had he been in the town named after him. You're still avoiding the focus of everyone's issues with you: that nobody here doubts that large extremes happened in the past. But the data here (Hansen and R & C) provide strong evidence for the frequency of heatwaves increasing - the Gaussian distribution flattening slightly and shifting to the right, and each year, a greater proportion of the Earth's surface experiences extremes. Without being pejorative, I do wonder if you get what probability is all about?
  15. Extreme Events Increase With Global Warming
    Norman @52 -"It was also the coldest February recorded in the US. It has the record number of consecutive days below zero in the lower 48th (41 days). Yes, hardly a surprise given this occurred early in the observational record. This asymmetry of warm vs cold records is discussed in Rahmstorf & Coumou, although I don't deal with it in the blog post. I you take a gander at Figure 1 in the post above, that's a gaussian (or normal) distribution. Keep moving that distribution to the right (climate warming trend) and the cold extremes (to the left) gradually diminish. In other words the frequency of record-breaking cold extremes decrease - as observed in figure 2 in both the GISS data and the Monte Carlo simulations.
  16. Extreme Events Increase With Global Warming
    Tom Curtis @46 You do have excellent posts. I would suggest you click on the source of the 1936 graph of the heat wave (1st graph). From the larger article the graph was part of: "Seventeen states broke or equaled their all-time record absolute maximum temperatures during the summer of 1936 (still standing records)." It was a large extent pattern and if you look into the article you will see it started in June and set state records, extended and grew in July and then persisted in August setting records in all three months so it was quite large and enduring. The amazing thing about 1936 is that not only was it very hot in the summer, it was the extreme of extreme years. It was also the coldest February recorded in the US. It has the record number of consecutive days below zero in the lower 48th (41 days). In the article they list many of the record high temps.
  17. Extreme Events Increase With Global Warming
    Norman @ 43 - Just to add to the comments made by others, the important point you miss is the warming climate leading up to the North American heatwave made a record-breaking warm extreme more likely. You provide evidence that actually supports the findings of Rahmstorf & Coumou. So once again: In a stationary climate (no warming trend) the probability of record-breaking falls (the 1/n rule). This doesn't mean that natural variability alone cannot break records, just that the odds decrease with each subsequent observation. In a warming climate the probability of record-breaking warm extremes increase. This assumes of course, that the standard deviation follows a gaussian distribution - which it does in the case of the GISS global and Moscow July temperatures. As Tom Curtis has already pointed out to you, arguing probability on the basis of a singular event is an illogical premise.
  18. Extreme Events Increase With Global Warming
    skywatcher @47 I ran a standard deviation of Bismark, North Dakota July 2011 data (should be fairly typical for that area it would seem as the average temp came very close to the long term average for this area). Using this standard deviation calculator found here. I entered data from here. into the standard deviation calcualtor. The results were: Mean: 84.26 F Standard Deviation: 6.07 The record high in July for Bismark is 114 F set in 1936. 114 F is sigma 5 (5 standard deviations away from the mean).
  19. Extreme Events Increase With Global Warming
    This Science Daily item might explain a few things that perplex some of us about extreme weather events . Erratic, Extreme Day-To-Day Weather Puts Climate Change in New Light I hope someone will soon do a post here on this AMS Journal of Climate paper "Trends in daily solar radiation and precipitation coefficients of variation since 1984." from Medvigy & Beaulieu. I don't recall their names but this stuff looks interesting and relevant for those trying to get their head around the implications or causes of extreme weather effects. It will be interesting even if it only evokes a more detailed analysis from others disputing or elaborating on the results they have so far.
  20. Extreme Events Increase With Global Warming
    muoncounter @45 "If you accept the Hansen paper's data as accurate - and you've posted a GISS graph, so I have to assume you do - then how can there not be an increased probability of heat waves?" I would agree that the average temperatures will be higher but the current amount of global warming would only increase the average a few degrees. That is because I do not feel that exterme heat waves are random fluctuations in the temperature field but are caused by patterns that develop. The NASA article I am linking to does suggest global warming may increase heat waves. That is because it is possible global warming of the oceans may produce more blocking events. In this way I can accept that global warming can lead to more heat waves. But the NASA article can easily explain the Hansen data posted in #5 by Albatross. Blocking patterns have been changing with time and are controlled by the ocean temperature. When researchers get a complete picture of what causes and maintains blocking patterns it will then explain if global warming will increase the probability of heat waves. If global warming causes blocking patterns to decrease then I would not believe the probability of heat waves would increase. Though I would believe the average daily temperature would increase. NASA article on blocking patterns.
  21. Extreme Events Increase With Global Warming
    "The point of this post is to determine how they came up with the 80% probabliltiy that the Moscow heat wave would not have happened without Global Warming even though a worse heat wave took place without Global Warming as the cause." Norman, do you think that when there is a 20% probability of an event, that it can never happen? Because that is exactly what you are suggesting above. It is partially why the authors did not say that the Moscow heatwave was a 100% probability AGW event. Next time you roll a die, I assume you'll think that because there is an 83% chance of rolling a '2' to a '6', you could never have rolled a '1' before? Compare the 1955 maps with the 2010 maps in comment #5. I think you'll be able to work out from that if your 1936 heatwave was larger or smaller than an event that stretched more-or-less from the White Sea to the Red Sea, with a 3-sigma area near enough the size of the USA. Add to that your conflation of absolute temperature differences with the assessment of what is 'extreme' in any area, and you seem assertively confused. Different regions have different assessments of what is 'extreme'. In very cold regions, sustained anomalies measured in the tens of degrees Fahrenheit are possible in winter; conversely, on small islands, anomalies of five degrees Fahrenheit may be enough to be 2- or 3-sigma 'extreme'. Tom and muoncounter have already said all this much more eloquently...
  22. Extreme Events Increase With Global Warming
    Norman @43: 1) Checking the gisstemp maps for July 1936 and July 2010, it is very clear that: a) The Russian heat wave of July 2010 covered a far larger area than did the US heatwave of July 1936; b) The Russian heat wave of July 2010 was hotter than the US heatwave of July 1936. As there is a discrepancy between the GISS and the map you provide on this point, it should be noted that it is not clear that your map represents July Averages rather than July Maximums. Note that the Moscow maximum was also about 12 degrees F above the mean, and other parts of Russia where hotter, relatively. Further, the GISS maps have a 1200 smoothing radius, so the higher Russian temperatures may be a product of their greater extent. Reducing the smoothing radius to 250 km (which should avoid that problem) increases the US July average peak to 6.6 degrees C (12 degrees F) but the Russian to 7.5 degrees C (13.5 degees F), which significantly reduces the disagreement between the two maps, but still shows the Russian heatwave as both hotter and more extensive. c) In 1936, it is evident that Russia also had a heatwave in July, of about the same intensity, but slightly smaller area than that in the US. As such an equivalent heatwave to the US heatwave of 1936 appears on as the third warmest record in the second graph of your post 4 above, where it comes nowhere near matching the 2010 event. Given the above, it is far from clear that the 1936 US heat wave was as hot as the 2010 Russian heatwave, let alone hotter. It was certainly not as extensive, nor as long lasting (as checking June data will show). Therefore the factual basis of your post is in doubt. 2) Absolute differences in temperature anomaly are not an appropriate metric for comparing heat waves. That is because different latitudes, different seasons and different have different levels of variability in temperatures. In general tropical temperatures are less variable than mid latitude or polar temperatures, while summer temperatures are less variable than winter temperatures. There are, however, significant regional differences in variability relating to geographical factors. A location bordered by hot dessert in one direction and an ocean with a cool current in the other will vary temperature greatly depending on the direction of the wind. Because of this variability, the correct measure of comparison is the variation in Standard Deviations for the regions of interest. That means if Dakota July temperatures are more variable than typical Moscow July temperatures, an equal absolute difference in temperature anomaly requires more explanation in Moscow than in the Dakota's (and vice versa). Further, larger areas (and greater durations) result in less variability (due to averaging effects). That means all else being equal we would expect the Russian heat wave of 2010, with its greater extent and duration, to be more Standard Deviations from the mean than was the US heatwave. However, though I suspect the Russian heatwave of 2010 to have exhibited a greater departure from the mean in Standard Deviations, you have not quoted the relevant statistic for the US heatwave of 1936, so I cannot categorically say, one way or the other. But equally, neither can you. Ergo you have no conceptual basis for your argument. 3 It is false to say, as you do, Global Warming was not the (more properly "a") cause of the 1936 heat wave. Global warming was present in 1936, and contributed to the increase in global temperatures relative to the start of the century. We know that because CO2 did not go from not being a forcing agent in 1947, to being one in 1975. It was a forcing agent in 1936, albeit dominated by natural forcings. Therefore it contributed to the temperature rise at that time. It follows that global warming contributed to every temperature event in 1936 (as also in 2010). It astonishes me that people keep on saying that a buttefly's flight in Japan could cause a storm in New York city as an example of the chaos of the climate system, but keep on reasoning as though a global forcing of 1.8 W/m^2 forcing due to CO2 (as of 2011) could have no effect. So the question is not whether global warming contributed to either heat wave. It did, to both, although more to the 2010 event. The question is only the statistical question of how much more likely a given event is given global warming. That has not been calculated for the 1936 event. If it were it would be likely to surprise a number of people. A significant contributing factor to the sharp rise in global temperatures between 1910 and 1940 was the reduction in sulfate emissions due to the great depression. Sulfate forcing tends to be regional in effect, and the epicenter of the great depression was the US. Hence the change in forcings due to anthropogenic factors in the US immediately following 1927 would have been disproportionately large. The contribution of CO2 forcing plus reduced anthropogenic aerosol forcing to the 1936 heatwave is very unlikely to have increased the probability of the extremes reached by 80%. However, it would be no surprise if the contribution was in double digits. How much it was, or wasn't, however, is pure speculation until a study is actually done. That means it would be wrong of me to claim the extremes were only reached because of global warming, but equally wrong of you, as you do, to claim that global warming was not a significant factor. 4 Finally, while it is undoubtedly true that global warming contributed to the 2010 Russian heatwave, nobody can say that such a heatwave could not have been reached by natural variability alone. There is no scientific evidence to suggest it is a roll of '13' on two dice, to use the popular analogy. What can reasonably be asserted is that there is an 80% chance that it would not have happened without global warming. That means there is a 20% chance it would have happened without global warming. So even if the 1936 US heatwave were all you say it is, that would only show that that 20% sometimes comes up. That is neither a challenge to the claim that there is an 80% chance that the Russian heatwave would have been a relatively mild event without global warming; nor a challenge to the claim that extreme events increase with global warming. In statistical arguments, as this necessarily is, citing a single datum as the basis of an argument is always a non sequitur.
  23. Extreme Events Increase With Global Warming
    Norman#43: "even though a worse heat wave took place without Global Warming as the cause." This is the same circular track you took us on in prior extreme weather threads. That there was a heat wave in history worse than 2010 (if that is in fact true) is irrelevant. Low probability events happen - that's why we use the 'rolling dice' metaphor. The point here is that in a warming world, we expect these events more frequently; perhaps even becoming the 'new normal' and even worse events to become the extreme. That is what the graphs posted here and here are saying. That is what the map posted here is saying: an observable increase in the occurrences of what were low probability events. If you accept the Hansen paper's data as accurate - and you've posted a GISS graph, so I have to assume you do - then how can there not be an increased probability of heat waves?
  24. The Debunking Handbook Part 1: The first myth about debunking
    I am guilty of trying to get others to see my point of view by stuffing 'facts' down their throats. If I can learn from this how to actually effect change in my audience, I will be delighted. No doubt, I will need to start by checking my own world view against this book: no good getting people to see things my way if I am wrong! Thank you John and Stephan.
  25. The Last Interglacial Part Five - A Crystal Ball?
    Sphaerica : I'm not sure what ClimateWatcher was asserting, because he says "The Eemian and Holocene optimums experienced roughly constant global insolation" (so, I guess "constant" means no global forcing, as you put it). But for Greenland Inlandsis behavior and its contribution to sea level rise, the differences in seasonal and regional forcing are probably relevant... or maybe not, precisely I don't know the year mass balance desequilibrium due to insolation in models, and it is the scope of my question. Hereafter, a recent Masson-Delmotte et al 2011 paper seems of interest for this question, but is unclear for me. On one hand, it says that "the IPSL-CM4 model shows similar magnitudes of Arctic summer warming and climate feedbacks in response to 2 × CO2 and orbital forcing of the last interglacial period (126 000 yr ago)". On the other hand, it observes that "Comparisons with Greenland ice core stable isotope data reveals that IPSL/LMDZiso simulations strongly underestimate the amplitude of the ice core signal during the last interglacial, which could reach +8–10 °C at fixed-elevation". So, I don't understand if the model is correct or uncorrect ! http://www.clim-past-discuss.net/7/1585/2011/cpd-7-1585-2011-print.pdf
  26. Extreme Events Increase With Global Warming
    Err, is the post at 43 meant to be serious? The author is conflating a number of issues and comparing apples to oranges. To mention a couple of other issues. I really have no idea where to begin. If it is serious effort, it is a striking example of just how far "skeptics" will go to delude themselves. Shocking.
  27. Extreme Events Increase With Global Warming
    Rob Painting @40 In your above article you have a bullet: "By seperating out the random (weather) component and the long-term (warming) component, the authors established there is a 80% probability that the 2010 July temperature record in Moscow would not have happened without climate warming from 1880-2009." From your Climate Progress link in post 40: "The Russian heat wave was, according to NOAA, roughly 5°C ( 9°F) above average for July." Here you have the US 1936 Heat Wave (extent and temp anomaly). This one was hotter than the Moscow Heat Wave where a significant area was above 10 F and then some area that was 12 F above. (Note: I do not know about the area covered by the Moscow Heat wave vs the US 1936 heat wave, I only know it was hotter). source. So in 1936 you have a worse heat wave than Moscow 2010 heat wave (hotter temps) but the temp anomaly for 1936 was less than zero. source. source. The point of this post is to determine how they came up with the 80% probabliltiy that the Moscow heat wave would not have happened without Global Warming even though a worse heat wave took place without Global Warming as the cause.
    Response:

    [DB] Fixed broken image.

  28. Extreme Events Increase With Global Warming
    Norman #37, can I refer you back to Albatross' inline graphic at 5 (the maps from Hansen et al 2011), when you are trying to tie individual events to GHGs. Albatross was responding to your #4 where you said "... evidence does not show or prove the conclusion that frequencies of heat waves will increase." Hansen's figure provides exactly that evidence, showing how the frequency and intensity of heatwaves is increasing across the world. Each year, you don't know where the big heatwaves will hit, but the percentage of the land surface being hit by heatwaves is increasing, and so it becomes progressively more likely that you'll end up under one. Moscow did in 2010, Texas this year. There were 3-sigma events in 1955 and 1975 (not 1965), but only a very few in a very few locations. The graphical analysis shown by Daniel in his inline comment at #13 shows how the frequencies and intensities are shifting. Now they cover appreciable fractions of the Earth's surface. Do you accept global warming drives that? If so, you must accept that more and worse heatweves are a consequence of our global warming, including these particular events. Each event might have happened in the 1950s or earlier, but it is extremely unlikely that they would have done.
  29. 2010 - 2011: Earth's most extreme weather since 1816?
    John Hartz @ 416 Here is an interesting article for you to read concerning stroms in Alaska. History of extreme storms in Alaska.
  30. Cardinal Pell needs to practise what he preaches on climate change
    Bernard J, @10, as far as Christian faith and climate change goes, my former missionary mother often points out to me that the book of Revelation describes something very close to the mid-level (neither worst nor best) scenario of business as usual:
    "1 I watched as the Lamb opened the first of the seven seals. Then I heard one of the four living creatures say in a voice like thunder, “Come!” 2 I looked, and there before me was a white horse! Its rider held a bow, and he was given a crown, and he rode out as a conqueror bent on conquest. 3 When the Lamb opened the second seal, I heard the second living creature say, “Come!” 4 Then another horse came out, a fiery red one. Its rider was given power to take peace from the earth and to make people kill each other. To him was given a large sword. 5 When the Lamb opened the third seal, I heard the third living creature say, “Come!” I looked, and there before me was a black horse! Its rider was holding a pair of scales in his hand. 6 Then I heard what sounded like a voice among the four living creatures, saying, “Two pounds[a] of wheat for a day’s wages,[b] and six pounds[c] of barley for a day’s wages,[d] and do not damage the oil and the wine!” 7 When the Lamb opened the fourth seal, I heard the voice of the fourth living creature say, “Come!” 8 I looked, and there before me was a pale horse! Its rider was named Death, and Hades was following close behind him. They were given power over a fourth of the earth to kill by sword, famine and plague, and by the wild beasts of the earth.
    As an atheist, I do not think global warming will bring on the Christian apocalypse. There is no hope for us that if we go that course there will be a last minute divine intervention. However, as a former candidate for ministry I can say that continuing with BAU does violate the Christian duty of stewardship of the Earth, and of concern for the poor. And that nothing in God's purported promise to Noah prevents a forthcoming apocaplypse.
  31. Cardinal Pell needs to practise what he preaches on climate change
    Jeffrey Davis @ 12 I entirely agree. Cardinal Pell has acknowledged that his climate scepticism is a personal view and not official Catholic Church teaching. If he was a business executive, lawyer or even a parish priest, would anyone listen to, or care about, these "personal views"? It is only as a leader of the Catholic Church that he gets an audience. I therefore put this question to both his Church and the wider community to consider: Is it appropriate for him to use the media profile and sphere of influence he has as a cardinal to speak out on issues such as as climate change on which he is so obviously not an expert?
  32. Extreme Events Increase With Global Warming
    muoncounter @38 I would not choose to read much as "absolute" especially in a very complex system that has many expert opinions. There is an individual Christopher C Burt that has done what I had hoped. Compiled data (for US) on extreme weather and wrote a book about it titled "Extreme Weather a Guide and Record Book" Here is a link that provides an introduction to this book with his conclusions based upon his actual researched data. Introduction to Christopher C. Burt's Weather book. They give a good sample of his book in this link, he does conclude Global Warming will increase heat waves. His evidence suggests that Global Warming will cause some increases in extreme weather in some areas but not in others. I thought you might like this.
  33. Stratospheric Cooling and Tropospheric Warming - Revised
    Interestingly, one of the thermosphere temperature estimates referred to in Beig 2006 above is from looking at satellite decay rates. Near Earth satellites decay due to friction with the atmosphere - the cooling thermosphere (~17C cooler over the last 30-40 years?) has shrunken, reducing air friction and producing measurable slowing of NE satellite orbit decay rates. So, in fact, the sky is falling...
  34. The Last Interglacial Part Five - A Crystal Ball?
    3, ClimateWatcher, Way to play with numbers. Well done. But, no, I'm sorry, that's a serious fail. The variance in summer insolation from peak to trough is 75 W/m2 with a net of... wait for it... zero. No net change in energy. No change in climate. Change in seasonal temperatures, yes, climate, no. Want to know something even more amazing? The variance in daytime and nighttime insolation is 1366 W/m2!!! Isn't that amazing! And yet global mean temperatures are relatively constant, because the net does not change. But if you add 3 W/m2 of CO2 doubling, where that is a net difference, and make that continuous, every minute of every day, for year after year, that makes a difference.
  35. Stratospheric Cooling and Tropospheric Warming - Revised
    MangoChutney - "Do you guys know if the rise in outgoing radiation has been measured?" Outgoing radiation changes, primarily changes in the spectral distribution of energy (challenging to get an absolute number, given multiple satellites over a short time period, but relative numbers at different frequencies, spectra are very accurate) show greenhouse gas changes. Given global warming the total energy radiated to space is decreased (it's accumulating rather than radiating), and the relative spectra clearly show reduced thermal emission to space at GHG frequencies. IR from the stratosphere (only a part of the emission to space) is lowered due to the lower temperatures there, due in turn to the energy not coming out of the troposphere as effectively because of higher GHG concentrations (radiative insulation). Specifically attributing a particular IR photon to an altitude is quite difficult, an underdetermined problem - but the physics of radiative absorption and emission are quite well known, and can be modeled. Temperature measurements (satellite microwave measures, radiosondes) make it possible with some degree of accuracy to determine temperatures of various levels of the atmosphere (the thermosphere temperature is hard to measure, although estimates can be made), and those temperatures match/validate the radiative models. And as Albatross pointed out, there's ongoing work in reducing the uncertainties in ozone, GHG, aerosol, and other drivers.
  36. The Last Interglacial Part Five - A Crystal Ball?
    Charts of the orbital induced solar variability serve to remind us of the relative insignificance of CO2 forcing. The Eemian and Holocene optimums experienced roughly constant global insolation. But look at the variance in summer insolation from peak to trough of more than 75W/m^2 and compare it to the 3W/m^2 (albeit global) of CO2 doubling.
  37. There's no tropospheric hot spot
    MangoChutney, I would be interested to know if you have read the 'Advanced' tab of this post. If you have, are you prepared to accept that your past assertions on Richard Black's blog, and I'm sure in many other places, tht the tropical tropospheric hotspot is an 'AGW signature that hasn't been found', is incorrect? Actually your assertions at the BBC on this thread have been almost a carbon copy of Monckton's quote above. So, will you do what few skeptics have the strength of character to do, and accept that you were wrong on this point?
  38. 2nd law of thermodynamics contradicts greenhouse theory
    1135, Fred, Looking back at Petty's book, you would be very well served to simply even read his introduction (as you clearly have not) rather than skipping ahead to the pretty pictures and then misinterpreting them.
  39. 2nd law of thermodynamics contradicts greenhouse theory
    1135, Fred Staples, You are mis-interpreting (or mis-representing?) what you have read in Petty's book. He does not "avoid the nonsense associated with back-welling radiation." He simplifies the diagram to represent as much as he needs at that point in the book (which is, after all, only page 6 out of 459 pages). Also note that all he does, for his purposes, is to simplify it for the reader who is only just learning the concepts, by translating the diagram from W/m2 to percentages and eliminating the atmospheric layer where possible for simplicity. There is nothing there but basic simplification to help educate a reader. [My strong advice to you would be to keep reading, instead of stopping on page 6.] The remainder of your comment is a gross misrepresentation of what his diagram conveys, and the mechanics of the atmosphere. You also thoroughly abuse the term "thermodynamically acceptable" as there is nothing at all in this discussion so far that has anything at all to do with thermodynamics. You are throwing the term around as if it must be accompanied by the ringing of chimes, heavy incense and Gregorian chants, and yet you misuse the term, or rather apply it with your own grand connotation or denotation, but entirely out of context.
    I do not want to continue to repeat myself.
    Nor should you. You need to instead either make a substantive argument behind your already invalid comments or else to learn more about the topic at hand, and to stop assuming that you in fact know more than all atmospheric physicists and climate scientists. Along those lines you will find a wealth of information about radiative physics in Petty's book, specifically the text after the introduction from which you got your diagram: Chapter 2. Properties of Radiation Chapter 3. The Electromagnetic Spectrum Chapter 4. Reflection and Refraction Chapter 5. Radiative Properties of Natural Surfaces Chapter 6. Thermal Emission Chapter 7. Atmospheric Transmission Chapter 8. Atmospheric Emission Chapter 9. Absorption by Atmospheric Gases Chapter 10. Broadband Fluxes and Heating Rates Chapter 11. RTE with Scattering Chapter 12. Scattering and Absorption by Particles Chapter 13. Radiative Transfer with Multiple Scattering Chapter 14. Representing the Phase Function Hmm. I seem to have missed the chapter on what's "thermodynamically acceptable." I'll have to go back and look for it.
  40. Eschenbach and McIntyre's BEST Shot at the Surface Temperature Record
    While I agree with much of what is said here (and on the site in general) I have a real problem with Table 2 and the thinking that went into it. First, the Fu data product is not the same as TMT. It measures a different (lower) layer of the atmosphere. Putting it in the same column with the RSS, UAH and STAR estimates of TMT is misleading at best. It can not be the same as either the RSS or UAH data from which is derived (and which version are you using here, anyway -- there are two versions on the NCDC site, one derived from RSS, and one derived from UAH) I have no idea how you got the number on the right-had side for Fu et al. There is no way to convert the Fu et al product to TLT. The Fu product should really be considered to be a replacement for TLT, since both are constructed with the same goal in mind -- removing the effect of stratospheric cooling from TMT. T Fu measures a layer higher in the atmosphere than TLT, and is free from the noise amplification in the TLT extrapolation procedure. See (Mears, CA, FJ Wentz, P Thorne and others, 2011, Assessing uncertainty in estimates of atmospheric temperature changes from MSU and AMSU using a Monte-Carlo estimation technique, Journal of Geophysical Research, 116, D08112, doi:10.1029/2010JD014954. and Mears, CA, FJ Wentz, 2009, Construction of the RSS V3.2 lower tropospheric dataset from the MSU and AMSU microwave sounders, Journal of Atmospheric and Oceanic Technology, 26, 1493-1509. For discussion of the noise problems in TLT. Back to Table 2. I understand how you get the number on the right hand side for Zou et al. I just think it has no basis in reality, or any predictive power. We have no idea what the STAR group will find for TLT until they do it. There is an important adjustment (for orbital height) for TLT that is not important for TMT or the other channels. We don't know what STAR will find for this adjustment, or how they will adjust for drifting satellite measurement times (for TMT, they use scaled version of the RSS adjustment -- will they do this for TLT? we don't know). You should also make it more clear that the simple arguments about tropospheric amplification do not apply outside the tropics. Thanks for listening. Carl Mears Remote Sensing Systems
  41. Philippe Chantreau at 08:06 AM on 17 November 2011
    2nd law of thermodynamics contradicts greenhouse theory
    "nonsense associated with back-welling radiation" It so happens that this nonsense should be dealt with, as the downwelling IR radiation does exists and has been modeled and measured. Extensive discussion of downwelling IR at the South Pole in this paper, with comparison of measured values and LBLRTM values under clear skies and various levels of cloud cover: http://www.webpages.uidaho.edu/~vonw/pubs/TownEtAl_2005.pdf In fact, in order to better deal with the nonsense, long term research has been conducted with the goal of refining the agreement between radiative models and observations, different lattitude this time: http://www.whoi.edu/mvco/description/InfRad.html Downwelling IR can be followed over the past few days at Martha Vineyard's Coastal Observatory: http://www.whoi.edu/mvco/description/InfRad.html Any kind of atmospheric model that denies or dismisses the downwelling IR radiation is inaccurate.
  42. Stratospheric Cooling and Tropospheric Warming - Revised
    104, MangoChutney,
    Do you guys know if the rise in outgoing radiation has been measured?
    Refer to KR's response in 102, and realize that your statement is slightly mis-phrased. We know that overall outbound radiation should be less, not more, as the planet has an energy imbalance and is warming. This state should continue until the planet reaches a new equilibrium temperature, at which point out must roughly equal in, on average. Part of the greenhouse effect is the fact that the earth should radiate energy from higher altitudes. The earth will radiate energy from higher in the troposphere and less overall from the cooling stratosphere, but when the system is in or near equilibrium, total energy out will equal total energy in (i.e. not radiate less, but simply sourcing that radiation from different altitudes). As KR said, determining the altitude at which this energy is emitted is problematic. Anyone else, please step in and correct me if I'm wrong or mis-stating any aspect of this.
  43. The Debunking Handbook Part 1: The first myth about debunking
    Can't wait to read this - thanks to both of you for writing it.
  44. The Debunking Handbook Part 1: The first myth about debunking
    Thanks John, I need this urgently for my future lectures :)
  45. Stratospheric Cooling and Tropospheric Warming - Revised
    Mango, We would be better able to help you if you answered my question @101. Specifically, what statements have you made that "they" have told you were wrong. I am not trying to be difficult, I am trying to focus the discussion. Thanks.
  46. Stratospheric Cooling and Tropospheric Warming - Revised
    @KR & Albatross Thanks. I know and accept the stratosphere has cooled, but it's nice to see a good graphic to illustrate. Ozone cools the upper stratosphere and warms the lower stratosphere (Clough and Iacono, JGR, 1995), do we know the pattern of cooling over the satellite period? Is it the whole stratosphere or just the upper stratosphere? Bob Guercio tells us "Therefore, these excited CO2 molecules will deexcite and emit IR radiation (Step 4) which, in the rarefied stratosphere, will simply be radiated out of the stratosphere. The net result is a lower stratospheric temperature.", so this is presumable measurable. Do you guys know if the rise in outgoing radiation has been measured? Sorry for all the questions, really am trying to understand
  47. 9 Months After McLean
    Fred @55, You are wildly, wildly off topic. Actually, revisiting your posts here, you have not yet been on topic (i.e., McLeans' ridiculous forecast). So enough with the trolling already to defend and/or try to distract from his ridiculous error. McLean is wrong, deal with it. That you cannot accept that fact (as unfortunate as it may be) is rather bizarre.
  48. The Last Interglacial Part Five - A Crystal Ball?
    PS : I mean "mm/y" for sea level rise (due to Greenland melting under a certain local forcing), of course, but maybe I should write Gt/y for ice loss if this kind of estimation come from ice dynamic models.
  49. 9 Months After McLean
    Very well. Can I suggest, as a valedictory comment, that you go to "Global Warming at a Glance, transfer to Hadley Centres new radiosonde product, and click onto the Met Office "frequently used plots and graphics". Look at the Global Lower Stratospheric Anomalies from 1958 to 2010. Certainly there is cooling from 1958 to 1992, before the surface and atmospheric warming periods, of about 2 degrees C per century. Are we to disregard the obstinately flat period thereafter? Finally, look at the "more images updated in near real-time", and click on the "Global and tropical trends" plot, full size png. The blue line is the trend at all altitudes from 1958 to 1978, all negative (cooling). The red and black are the trends, positive at just over 1 degree per century, which depend on the (relatively) sharp increases from 1999 to 2001. So I ask again. Does this data give any support to a TOA theory of AGW, caused by the exponentially increasing CO2 levels?
    Response:

    [DB] Off-topic struck out.  And, for the record, you have studiously avoided answering my question to you in my response to your previous comment.

  50. The Debunking Handbook Part 1: The first myth about debunking
    Nice summary; I look forward to more detail in the posts to follow. To my mind, what's particularly tricky is the type of effect in the Skurnik et al. paper (your reference #5 above). In that research, people understand that information is false when it's first presented. The problem arises when the "core proposition," so to speak, stays familiar over time, but the details of the warning/debunking fade from memory. That's when people show a strong bias to think that the familiar information is true, even when they accepted that it was false when they first learned it. This "backfire" develops especially quickly for older adults, people under time pressure, etc., and it's not clear what to do to alleviate the problem. Best advice is probably to rely on written back-ups to one's memory, but that's not always practicable...

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