Tornado madness

by Judith Curry

I’ve been pretty clear about where I stand with regards to the attribution of extreme events to global warming, e.g. see this thread.  The recent tornado outbreak in the southeast U.S. has spawned a number of statements and articles about the cause of the outbreak including, inevitably, global warming.

Why am I not surprised?

• Peter Gleick on the Huffington Post: A cost of denying climate change

Violent tornadoes throughout the southeastern U.S. must be a front-page reminder that no matter how successful climate deniers are in confusing the public or delaying action on climate change in Congress or globally, the science is clear: Our climate is worsening.

•  ThinkProgress: Storms Kill Over 250 Americans in States Represented by Climate Pollution Deniers.

The title speaks for itself on this one

• From the WonkRoom:  words from Trenberth, Mann and Schmidt.

Dr. Kevin Trenberth, one of the world’s top climate scientists, who has been exploring for years how greenhouse pollution influences extreme weather, said he believes that it is “irresponsible not to mention climate change” in the context of these extreme tornadoes.

Michael Mann: The fact remains that there is 4 percent more water vapor–and associated additional moist energy–available both to power individual storms and to produce intense rainfall from them. Climate change is present in every single meteorological event, in that these events are occurring within a baseline atmospheric environment that has shifted in favor of more intense weather events.

Gavin Schmidt:  It is a truism to say that everything has been affected by climate change so far and therefore this latest outbreak must in some sense have been affected, but attribution is hard and the further down the chain the causality is supposed to go, the harder this is. For heat waves it is easier, for statistics on precipitation intensity it easier – there are multiple levels of good modelling, theory and observations to back it up. But we have much less to go on with tornadoes.  JC comment:  actually this one belongs in the “cooler heads” category, kudos to Gavin

Cooler heads

• From NOAA, a historical perspective.

• Washington Times:  Tornadoes Spinning Global Warming

The case linking tornadoes to global warming is even sketchier, and the science is far from “settled.” A 2007 NASA study predicted that the number of tornadoes would increase with global warming. A 2009 study by University of Georgia found the opposite. The number of recorded tornadoes has risen in the last 20 years, but the rise coincides with greater use of Doppler radar and other advanced means of detecting tornadic activity, creating an acute issue of data artifice. A definitive answer to the question may not be possible. Given this lack of proof, the alarmists are forced to fall back on the question “what if?”

• Newsbusters: includes comments from Greg Forbes:

Yeah, it really has been a remarkable April, certainly a record April. It may be the most tornadic month of any month on record. It certainly, the atmosphere has been in a frenzy. The jet stream just keeps blasting across the country, and then the warm moist air from the Gulf of Mexico just keeps feeding the instability and so we’ve had tornado after tornado…

• Fox News: Interview with Greg Carbin:

Greg Carbin, the warning coordination meteorologist at NOAA’s Storm Prediction Center in Norman, Oklahoma, said warming trends do create more of the fuel that tornadoes require, such as moisture, but that they also deprive tornadoes of another essential ingredient: wind shear.

“We know we have a warming going on,” Carbin told Fox News in an interview Thursday, but added: “There really is no scientific consensus or connection [between global warming and tornadic activity]….Jumping from a large-scale event like global warming to relatively small-scale events like tornadoes is a huge leap across a variety of scales.”

Asked if climate change should be “acquitted” in a jury trial where it stood charged with responsibility for tornadoes, Carbin replied: “I would say that is the right verdict, yes.” Because there is no direct connection as yet established between the two? “That’s correct,” Carbin replied.

• Time: Tornadoes, Climate Change, and the Disaster Gap

2009 study by University of Georgia researchers suggested that drier autumns and winters that might be seen due to warming could actually lead to fewer tornadoes developing during the spring season, at least in the Southeast, though the scientists cautioned that their data was preliminary. A research project by Michael Pateman and Drew Vankat found that the frequency of tornadoes had increased between 1950 and 1999—though better detection likely played a significant role in those statistics. But if there’s strong evidence that climate change and tornadoes are connected, researchers have yet to uncover it—and given how difficult and time-consuming it is to attribute a weather event to warming, don’t expect a firm conclusion soon.

• Physorg.com: Tornadoes whipped up by wind, not climate

Violent twisters that famously rip through the US south’s “Tornado Alley” are formed when strong jet winds bringing upper-level storms from the north interact with very warm, humid air mass from the , said David Imy from the NOAA Storm Prediction Center in Norma, Oklahoma.

On Wednesday, a particularly potent storm was whipping up around the heart of that tornado-prone corridor where the states of Arkansas, Oklahoma, eastern Texas and northwest Louisiana meet, noted Kristina Pydynowski, a senior at the AccuWeather.com website.

Sparking the severe thunderstorms from that point was the much warmer air arriving from the south, over the tropical Gulf. The combining winds at differing altitudes, said Pydynowski, created “significant twisting motion in the atmosphere, allowing the strongest thunderstorms to spawn tornadoes.”

•  Climate Central: Tornado Outbreak Raises Climate Questions

Those of us who write about climate change are often accused of attempting to link every unusual weather event to climate change, as if increasing air and ocean temperatures can explain everything from hurricanes to snowstorms. In this case, with the worst tornado outbreak since at least the 1974 “Super Outbreak”, and with the most tornadoes for any April since records began in the early 1950s, it’s important to understand that the scientific evidence indicates that climate change probably played a very small role, if any, in stirring up this violent weather. This might disappoint some advocates who are already using this to highlight the risks of climate change-related extreme weather.

•  Mike Smith of Meteorological Musings, has a number of interesting and relevant posts on meteorology of this outbreak:

http://meteorologicalmusings.blogspot.com/2011/04/super-supercell.html
http://meteorologicalmusings.blogspot.com/2011/04/leave-it-to-ny-times-to-write.html
http://meteorologicalmusings.blogspot.com/2011/04/question-of-day.html


104 responses to “Tornado madness

  1. According to graph posted on WUWT the other day

    http://www.vukcevic.talktalk.net/TN.htm

    as the temperatures fell from 1950-1975, the tornado number was on rise, to fall off at a similar rate with the subsequent warming.

  2. RP Jr. has two posts up on this also, a preliminary one from Thursday and a re-print of a Bill Hooke blog post from yesterday.

    I saw someone criticize the graph Roger used re: tornado deaths, but if you limit yourself to the last twenty years (to account for better detection) it still doesn’t seem show much of an upward trend (despite the fact that population density continues to increase – as pointed out by Hooke).

  3. “Dr. Kevin Trenberth, one of the world’s top climate scientists, who has been exploring for years how greenhouse pollution influences extreme weather,”

    Should this not say “exploiting” rather than “exploring”?

    • As Jonathan Gilligan says below, the Trenberth quote completely misrepresents what he said.

      • Trenbeth: “With global warming the low level air is warm and moister and there is more energy available to fuel all of these storms and increase the buoyancy of the air so that thunderstorms are strong.”

        Is there ANY evidence warm moist air causes more thunderstorms which then causes more tornados?

        Nope. He’s just a Climate Ghoul trying to scare the uninformed … like Nick.

      • Jonathan Gilligan

        Bruce: You ask whether anyone knows if moisture is important for causing thunderstorms and tornadoes. The answer is yes, it’s well known that it does.

        I’m not an expert at the meteorology of convective storms, so understand that I’m only talking about the very basics, which I do understand; not the details, which are beyond me: The contribution of moisture to thunderstorm and tornado risk is clear at the freshman meteorology level: All other things being equal, raising the specific humidity raises the virtual temperature and lowers both the convective condensation level and the saturated adiabatic lapse rate. All of these changes mean that the air becomes more unstable and thus more prone to strong convection.

        Increasing specific humidity also increases the convectively available potential energy (CAPE), which is the amount of energy available to drive thunderstorms or tornadoes. The bigger CAPE is, the bigger the storm you can get.

        There’s a lot more to it than this, but all meteorology agrees that moisture is a crucial component of the probability of initiating a storm and of the severity should a convective storm develop and that if all other things are equal, the more moisture is in the air, the more frequent and severe convective storms will be. If you want to know more, don’t bother with climate science. Go get a good textbook on meteorology and read about stability, convection, and thunderstorms.

        It’s fine to argue whether climate change has anything to do with the current spate of tornadoes. My position is that (a) I’m not an expert on tornadoes so my opinion on tornadoes is pretty worthless and (b) if you want my worthless opinion anyway, it’s that the real experts don’t know whether climate change will affect tornadoes.

        But I do have skill at reading what people write, and it’s clear that Trenberth is not fear-mongering about a connection between climate change and tornadoes. If people want to attack what he says, fine. But attack what he actually says and don’t quote him out of context so you can rebut a straw man.

      • Roy Spencer: “Tornadic thunderstorms do not require tropical-type warmth. In fact, tornadoes are almost unheard of in the tropics, despite frequent thunderstorm activity.”

        Trenbeth is a fear mongering Climate Ghoul.

        And Jonathan, is there any evidence that it was unusually warm?

        From what I’ve seen, the evidence is that it has been unusually cold northwest of Alabama and Alabama had the 82nd warmest March in 117 years — meaning 35 years were warmer.

        Could it be the difference in temperature?

        1974 was the worst previous year and both 2011 and 1974 are years when the PDO is in its cold phase. I also believe 1974 and 2011 were La Nina years.

      • Correct, both 1974 and 2011 are years of strong La Nina’s. It must be unlikely that that is a coincidence. Since La Nina’s result in cool temperatures it may well be that global warming would result in fewer tornadoes, (notwhithstanding the extra water vapour in the troposhere)

      • “The Trenberth quote completely misrepresents what he said”.

        Dispassionately, Nick, read your words again.
        =================

      • Nick, the doomsayers are wrong. The upside down null is seditious to science. CO2 has an effect. Let’s find out what it is, ‘cuz we don’t know yet.
        ============

      • Yeah. That’s a gem.

      • Brandon Shollenberger

        Even if you dislike the portrayal, it is absurd to say Trenberth was completely misrepresented.

      • It is a misrepresentation. Trenberth gave a careful and thoughtful analysis of the possible role of climate change in extreme events. Here this is reduced to caricature.

      • Then he caricatured himself. He should have said it is ‘irresponsible to mention climate change’ in the context of these extreme tornadoes.

        Now, if he was using ‘climate change’ to mean the varied phase of the PDO, he’d be right. But we all know he was blaming man for a CO2 caused event.

        You do know, Nick, about his perversion of the null, don’t you? Do you like that?
        ==============

      • Nick, as Hunter points out below, there is a fork in the road coming. Better to be a lukewarmer than an alarmist. These alarmists are going mad with the lack of warming, and the troika of Mann, Schmidt and Trenberth all reacted with the Folies a Troix.

        As others have pointed out, the adults at NOAA, who’ve already called this ‘Spring’ or weather, rather than climate, must be starting to marginalize alarmist reactions like we’ve seen from these three.

        You’ve got lots of credibility, Nick. Cherish it, and keep it.
        ===============

      • Trenberth was apparently interviewed twice (at least). My quote was from the email interview with ThinkProgress (in my wonk room link).

        Lets read between the lines on the Revkin interview. Trenberth starts out “not sure what you have,” from which I infer (along with the actual text in Revkin’s post) that Revkin prefaced his question with some sort of statement that a number of tornado experts don’t think that that that we understand tornadoes very well and there is no global warming signal. Trenberth comments on what he thinks Bluestein and others might have said. But Trenberth’s punchline is very clearly his own statement from his 2009 Congressional Testimony:

        The record breaking numbers of tornadoes and deaths in the U.S. in 2008 probably also has a modest global warming component. Tornadoes are most common in the spring and early summer in weather systems moving across the U.S. that bring warm moist low-level air flowing from the Gulf of Mexico into the storms, while drier westerly winds aloft create wind shear that leads to rotation and thus tornadic thunderstorms. Because the Gulf air is warmer and moister than it would otherwise have been 30 or more years ago, the instability of these storms is enhanced. The effect is not measurable owing to the nature of tornado statistics which mainly reflect increasing numbers of people in more places.

        So what do I conclude from this? Trenberth will take the attribution of extreme weather events to global warming as far as he can. Which isn’t very far if you have a good reporter like Revkin interviewing a number of experts on the topic.

        p.s. and don’t forget Trenberth’s statement on the null hypothesis:

        Given that global warming is unequivocal,” climate scientist Kevin Trenberth cautioned the American Meteorological Society in January of this year, “the null hypothesis should be that all weather events are affected by global warming rather than the inane statements along the lines of ‘of course we cannot attribute any particular weather event to global warming.’”

      • steven mosher

        lets cut to the phsyics claim he makes
        “Because the Gulf air is warmer and moister than it would otherwise have been 30 or more years ago, the instability of these storms is enhanced.”

        1. what does he mean by instability and how is it measured.
        2. Is there even a weak relationship between temp and moisture and instability.

        It seems entirely plausible that one only needs a certain amount of heat and certain amout of moisture to trigger instability. Increasing above those levels may have no effect whatsoever.
        without any firm evidence for his statement, or any operational way to quantify it or test it, it seems like a nice speculation.

      • Seen Tisdale’s latest at Watts Up? No trend in Gulf temps.
        ===============

      • Darn, you beat me to it.

      • steven mosher

        Yes, Trend is not important, think a bit. Look at the questions I asked.

        1. what does he mean by instability.
        2. what is the relationship between heat and moisture and instability.

        Lets say for example, that the temp had to be over 74 degrees F.

        Trend will only tell you the relationship between prior years and current years. Going from 0F to 30F would be a huge trend, but it wouldnt tell you anything about the questions I asked. I don’t think trenberth is right (or wrong) I think he points at interesting questions. Bob doesnt look at what I’m suggesting. nice work, but not an answer to my open questions

      • Because the Gulf air is warmer and moister than it would otherwise have been 30 or more years ago, the instability of these storms is enhanced.

        There’s just so much wrong with that statement.

        Is Trenberth so young that the fails to remember the tornados of the 20′s, 30′s and into the 50′s and 70′s of the last century? Is he so stupid that he doesn’t even research his statements prior to opening his mouth?

        He’s blaming the tornadoes on conditions that supposedly obtain now, but did not exist 80-90 years ago. Then how does he explain this -

        Or this –

        http://www.norman.noaa.gov/2009/03/us-annual-tornado-death-tolls-1875-present/

        Is he so blinded by ideology that he doesn’t see the disconnect there? Or doesn’t he care?

        So many questions, so few answers, so little respect.

      • Here is Bob Tisdale on the Gulf of Mexico SSTs.

        No trend apparently.

      • Jonathan Gilligan

        Judith: When I read Trenberth’s Senate testimony, what I see is that he’s saying he guesses that there’s a global warming component to tornadoes (opinion), but as a scientist he’s also making it clear that this opinion can’t be factually tested because “The effect is not measurable owing to the nature of tornado statistics which mainly reflect increasing numbers of people in more places.” Is there anything wrong with clearly distinguishing one’s opinion from the facts and offering both?

        Similarly, in the ThinkProgress interview you quote he clearly says, “Tornadoes come from thunderstorms in a wind shear environment. … There is no clear research on changes in shear related to global warming.” This doesn’t sound to me like someone pushing conclusions ahead of where the facts will support them.

        Regarding the null hypothesis quotation: I don’t know the context, but when I read it as you quote it, he’s saying “affected,” not “caused,” not “made worse.” Thus, it seems to me both uncontroversial, and sufficiently vague as to be useless. Affected a lot or a little? Amplified or diminished? Sure climate affects weather, but the trick is to figure out how and how much. Personally, I wouldn’t make a statement like that because I don’t find it useful; but I also don’t see anything scientifically wrong with advocating that take on things.

        Wouldn’t it really be a better use of everyone’s time to have productive conversations and arguments about ideas than to put quite so much effort into attacking people’s integrity and drawing up lists of who’s naughty and nice? There’s too much of that on both sides of the political divide.

      • Jonathon –
        Wouldn’t it really be a better use of everyone’s time to have productive conversations and arguments about ideas than to put quite so much effort into attacking people’s integrity and drawing up lists of who’s naughty and nice? There’s too much of that on both sides of the political divide.

        Two statements in there – and the answer to both is – YES.

        Now tell me – which side of the dance floor has said repeatedly and consistently that “the science is settled” and “the debate is over”?

        Several months ago there was a conference in Portugal – Who was NOT there?

        The answer is still “yes” – but who would sit on the other side of the table from the skeptics? I know people who could kidnap them and deliver them to wherever that table is located, but that’s not a reasonable solution.

        The proposal of unworkable solutions is, to a greater degree than the science, what this entire debate is about. Do you have any workable solutions? I, for one, would like to hear them.

      • There seems to be a focus here only on the warmth of the southern side of the frontal boundaries. Tornadoes are not caused by warmth alone, they are caused by the interaction of the warm on the south side with the cold on the north side. If the warm side is warmer and/or the cold side is colder, either or both can magnify the storms.

        After a warm and mild mid-winter, the Pacific Northwest has had a cool and wet late winter and early spring, possibly due to the now-ending La Nina, and these storms make for the cold side of the equation.

        I think that the air mass from the south is strongly affected by the Gulf, from whence it comes, and sea surface temps are again high. Isn’t that why Colo State is again predicting a bad Atlantic hurricane season? So we might have La Nina on the north and AGW on the south combining to make for this terrible season. But as others said in your quotes, it is harder to measure this for tornadoes than other kinds of weather events.

      • Brandon Shollenberger

        Your response to me is a misrepresentation. I never addressed whether or not Trenberth was misrepresented. I only commented on whether or not he was “completely misrepresented.” For him to have been completely misrepresented, the representation couldn’t have any accuracy. It would have to be completely misleading.

        That obviously isn’t the case, a point you apparently acknowledge by changing the argument.

  4. The upside down null
    Pervades the essence of life.
    You are guilty: Die.
    ==========

  5. The best part of this post – including the usual predictable responses – is the adjectivisation of “tornado” to “tornadic”. Truly the possibilities of the English Language are endless.

  6. Is anyone else feeling as dispirited as I am regarding the self-righteous anger and profound ignorance on the part of the warmsters. Regarding the tornadoes, there was never any doubt there’d be cries of “See! It’s global warming and all you deniers are guilty of murders!” Same deal with the floods, the Russian heat wave, and the recent tsunamis (due to supposed rising sea levels).

  7. Jonathan Gilligan

    It seems unfair to quote Trenberth in the way you do here, without saying anything about the part of his Wonk Room statement that emphasizes the importance of our ignorance about the effects of climate change on wind shear. You should also look at his more extensive comments to Revkin at Dot Earth:

    The effect is not measurable owing to the nature of tornado statistics which mainly reflect increasing numbers of people in more places.

    Statistics on tornadoes are unreliable and exhibit spurious upward trends that are known to correspond to more people being in more places to see them. …

    The effects of climate change … on wind shear and storm tracks are less clear.

    … the biases in climate models in reproducing the basic conditions ripe for tornadoes is not as well reproduced as one would like, and how one “corrects” for those biases (downscales) is subject to problems.

    This sounds as though he belongs firmly in your “Cooler Heads” category.

  8. Trenberth, Mann and Schmidt – the three wise alarmist monkeys .

    • No here’s someone interested in the productive conversation. Calling people monkeys is always such a productive approach.

      • Calling people monkeys is always such a productive approach

        Have you any evidence that the three entities in question have no “monkey-related branches of the tree” in their ancestry? That would come as a surprise to Darwin and evolutionary theory. And to me as well. :-)

        It would actually generate a whole new view wrt the origin of the species and the origins of life. Are you suggesting, perhaps, an extra-terrestrial origin? Please note that that possibility is already under investigation (seriously) wrt the main branches of the tree. But perhaps you’re suggesting an alternate tree? That would be interesting, but kinda hard to prove.

        Sounds like your theory needs some work. Keep us informed of your progress. :-)

  9. “JC comment: actually this one belongs in the “cooler heads” category, kudos to Gavin”

    Judith – please can you explain why you think this is a comment worthy of “kudos”? For example, what evidence is there that links heat waves to CO2? Same again for precipitation intensity? Thanks

  10. Frankly anyone who claims to be informed on AGW, claims they believe in it and does not condemn those exploiting this weather tragedy to push an agenda has no standing to discuss the issue further in any decent or fact-related forum.

    • Hunter,

      The usual water carriers for Trenberth & Co and co will always come out with the most tenous defence of the indefensible. It is their habit to go to every blog and do this shameless defending. Some people have no shame.

      • I would say that this is a fork in the road. Those believers who fail to condemn this exploitative dishonesty in no uncertain terms should be seen as shallow untruthful hacks.

      • Trenberth’s statement to Think Progress by way of an e-mail, as reported by them is extremely clear. The words, intent, everything stands out.

        To defend that and claim that his words are misrepresented quoting some other article in NYT, is a deliberate shamless act intended to mislead, by these apologists.

      • Well said, but a fork in the road is hard to see when you are wearing blinders. The shame is that they do not see how shameful they truly are. I am not speaking of the hucksters but rather their enablers who have incrementally salved their conscious by assuming some mythical middle ground between right and wrong.

      • You don’t understand how piety works. Piety is a “get out of any responsibility under any circumstances” card. That’s why it’s so popular.

  11. The ground was laid for this by Brad Johnson who basically fulfilled the role of biblical prophet calling it punishment for selecting the wrong leaders in Republican states. All he forgot was to tell the Pharaoh ‘Let my people go!’

    • Tom –
      I suspect he fails to understand the consistent and unenviable historical fate of “biblical prophets”. That’s what comes of a lack of grounding in history.

  12. James Belanger

    There is also the other side to this attribution issue. I’ve read and seen a number of news articles now ‘attributing’ the recent series of tornado outbreaks to La Nina (CNN, MSNBC) or changes in the intensity of the jet stream (see Jim Cantore on NBC Nightly News)–as if these type of large-scale ‘natural’ changes have never before occurred until now… What’s puzzling about any type of attribution conclusion is that no one has had the time to actually do the type of analysis that is really required. The SPC meteorologists are approaching the issue from the point-of-view of a short-term weather forecaster, whereas the climate hawks like Mann, Trenberth, etc. are espousing the party line that every extreme weather event must be to some extent tied to anthropogenic climate change.

    It’s human nature to want to understand how and why something like this has occurred. But I simply wish the public, media, and even these scientists with a selective point-of-view would exercise due diligence before anyone provides attribution comments one way or the other. Is it possible anthropogenic climate change had some type of impact, sure it’s possible. Is it more likely this event represented a nonlinear combination of optimum environmental conditions that would have occurred regardless of human-induced climate change, e.g. strong low-level wind shear, ample instability, and large supply of low-level moisture–absolutely! However, I think the best scientific answer at this point in time is ‘we really don’t know’. So let’s quit pretending like anyone has the answer, and instead do the hard work that’s required to answer these basic attribution questions.

    • I posted a tornado forecast on here back on March 2nd, explaining the process of how the lunar declinational tides drive the severe weather outbreaks, I stopped dropping in dates to expect tornadoes on the 18th of April. This was a mistake because I then missed giving a forecast for the period when this latest swarm of tornadoes occurred.

      http://research.aerology.com/severe-weather/tornadoes/tornado-forecast-verification/

      The biggest outbreaks of tornadoes occur in the spring when the apparent solar declination crosses the equator and then every time the moon crosses the equator, it assists the tidal pull of the meridional flows that make up the lunar declinational tides, the in phase Northern movement creates the cyclonic wind patterns that take advantage of the topographical height of the Rockies to pull warm moist gulf air masses on the lee side, and cold dry air masses over the mountains. The timing of these tidal air mass clashes is very predictable, from Maximum extension North or South, and up to 5 days after, and when the moon crosses the equator headed North, for a day fore and aft.

      Almost all of the strong and heavy outbreaks will fall into these days [about 25%] of the 27.32 day period. the tornado outbreak of 1974 and this last month have the same thing in common, the lunar declination at culmination is ~23 degrees. We are in the same type cyclic repeating pattern of global circulation flow patterns, that drive the weather the way it does.

      http://research.aerology.com/lunar-declinational-affects-on-tornado-production/

      Should help you to understand how it all happens and how to improve the range of forecast out to several years, for these periods of severe weather outbreaks. Giving forecasters a chance to warn the public in advance that the probabilities will be higher than normal.

      The related maps I generate from the detailed archived weather data from the past three cycles [going to use four cycles in the improved, updated process that includes Canada and Alaska, due out in a couple more months]
      have been on site for three years, is that enough of a warning time to put in a storm cellar?

      Just trying to be helpful
      Richard Holle

  13. “madness” – that’s the right word. The latest bout of hysteria among the AGW Puritans is their shrill call for climate-Salem witch trials for so-called denialists. To think we live in an age of enlightenment. It’s gotten so bad that they’ve succumbed to using spectral evidence. The parallels to the 17th century with hunts are simply mind-boggling.
    I’ll be sure to keep my kids away from academia.

  14. Climate change is present in every single meteorological event

    So climate isn’t weather but weather is climate?

  15. Whatever attribution there is to the question, none of it is going to be absolute.

    Not all the heat, not all the humidity, not all the wind shear come from any one distinct origin.

    At best, we have attribution by parts, straws (and straw men) breaking figurative camel’s backs, undefinable tipping points that can never be proven, and historical records without enough record-keeping history to detect or judge.

    Perhaps 22% of the CO2E has human origins from the past quarter millennium (maybe not, but this could be a good rough estimate of what might be provable with the current state of science; I’m not going to argue it or support it here, just call it a ‘what if’).

    Perhaps some fraction of that CO2E translates into net positive feedbacks. (4% more humidity? ‘What if’ that’s plausible?) Perhaps some fraction of that CO2E and positive feedbacks, lowered polar albedo due particulates, etc. and whatnot, altogether does amount to something that is part of the whole.

    Contentious though all those parts are each in their own way, it seems reasonable to seek to understand what may be an attributable source for loss against America’s bottom line.

    It’s not whether the cause of any one event, or trend, or nuanced shift of weather can be attributed to any single atom of CO2E emission; it’s the price those who benefit by emitting are willing to pay to those who are exposed to the increased risk at the time of the decision to emit, that matters.

    That attribution at that time is the one that matters. That attribution should be the price the market is willing to bear, and the owners of that CO2E risk, per capita, are going to demand, that ought be at issue.

  16. John Carpenter

    “Climate change is present in every single meteorological event, in that these events are occurring within a baseline atmospheric environment that has shifted in favor of more intense weather events.”

    I’m enjoying an intensely sunny 68 degree F day today… thanks climate change!

  17. Do Mann, Trenberth and Schmidt live within tornado alley ?

    There’s the probem. If they did then they would know.
    If they had eyes and paid attention to what they saw over their years.
    NOAA has state-of-the-art stations here, they see, they know,
    trust their words instead. (Don’t fail me NOAA, keep CO2 out of this)

  18. Re: Tornado madness, 4/30/11

    One should never get involved in verbal questions or questions of meaning, and never get interested in words. If challenged by the question of whether a word one uses really means this or perhaps that, then one should say: ‘I don’t know, and I am not interested in meanings; and if you wish, I will gladly accept your terminology.’ This never does any harm. One should never quarrel about words, and never get involved in questions of terminology. One should always keep away from discussing concepts. What we are really interested in, our real problems, are factual problems, or in other words, problems of theories and their truth. We are interested in theories and how they stand up to critical discussion; and our critical discussion is controlled by our interest in truth. Popper, K., Objective Knowledge: A Realist View of Logic, Physics, and History, [reported in "Objective Knowledge (1972)", Clarendon Press] 1966, Section 4: Realism in Logic.

    More concisely, Popper said,

    [D]efinitions do not matter … . Id.

    This from the man to whom many attribute the essential principle of falsification in the scientific method. Won’t someone please tell me and the World of one scientific theory with a falsification clause? Popper’s model of science was universal instantiation, UI, leading to the All Swans Are White model that requires falsification with a black swan. That is not how scientific models work. They are of the form of the logic sentence called a hypothesis, C -> E, where C is cause and E effect, and causality is temporal. The Cause is the setup, and the Effect is what will result.

    Furthermore, scientific models can tolerate no ambiguity. Even long-necked aquatic birds will not substitute for swans. Nowadays, we need the DNA genome. Contrary to Popper, definitions are irreplaceable. Nor is science about truth as Popper suggests. Truth is defined in logic and mathematics. Science is all about models with predictive power.

    Popper’s error with definitions is repeated throughout Climate Etc. It is the problem of subjectiveness. It is the problem of postmodernism. It is anti-objectivity, and far from illuminating science, it is anti-science. Science is the objective branch of knowledge.

    Attribution, uncertainty, catastrophes, including tornadoes, have all been treated subjectively and unscientifically here. Attribution is a regular problem is science. It requires a prediction, as in the extrapolation of the track of a particle, with a box of uncertainty placed around the predictions. When a timely detection occurs in the box, an attribution can not only be made, but quantified. It is not the seat of the pants rubbish posted here by the big names in AGW advocacy.

    AGW indeed predicts a catastrophe, a particular kind of catastrophe and a particular time. Every catastrophe is not confirmation of AGW. That is an erroneous attribution.

    Climate is unable to predict one tornado or one catastrophe. It is averages, with a minimum span of 30 years. It is not a mapping from averages to weather; it is a map from averages to averages.

    An insurance catastrophe is measured in dollars, or percent of annual earnings. Tornado and tsunami disasters are two dimensional catastrophes, measured in deaths by property damage. These are events, even in clusters. Climate models estimate global average surface temperature, first and foremost. The key parameter is climate sensitivity. These various models with catastrophes don’t work in the same coordinate system, in the same space.

    Dempster, discussed recently here, lambasted IPCC for having two different non-standard definitions of uncertainty. He was wrong. IPCC has three. Then Dempster wandered off into his pet conjecture, the DS model for evidence. This model attempts to predict from subjective probabilities, which are explicitly excluded from science, as are all things subjective. Dempster admits his model is subjective, but he proposes that an investigator assign a number, r he called it, to his degree of Don’t Know (i.e., Ignorance). How in the world is some climatologist, for example, supposed to assign a number to something he doesn’t even know exists? Or, to something he has erroneously ruled out (i.e., already attributed 0 to its r)?

    Tornado madness is indeed well named.

    • Jeff Glassman, interesting position, and I agree it seems. In fact that so portrays what I just finished posting here, see if this an example of what you are saying:

      http://wattsupwiththat.com/2011/04/30/are-gulf-of-mexico-sea-surface-temperature-anomalies-near-to-record-levels/#comment-651285

      I wrote that kind of boyish for readers not too planted in science but it seems this is exactly what you are saying. They have monthly means data on temperatures worldwide, and they have monthly means on humidity worldwide, and they have monthly means on wind velocities worldwide, and upper-level too. But, none of this data is every going to predict tornadoes. It takes a combination of all and more importantly it takes the INSTANTANEOUS combination of all of those to predict one.

      NOAA has improved much in knowing the probabilities of all of these factors within days and hours, I clap. My life often relies on their best guess data (probabilities). Definitely on the huge improvement in radar technology. The averages can say all conditions are present but it doesn’t mean it will ever happen because of the necessary to also be correct in time and space of all of these conditions. Smeared data over time destroys this.

      But for these far removed scientists looking at mere averages to say they “KNOW” what is “CAUSING” them and more importance frequencies, it’s a huge fallacy on their part. They made fools of themselves scientifically.

      • Re: Tornado madness, 4/30/11 Errata

        On 4/30/11 at 6:48 pm, I accused Popper of thinking that science models were examples of universal instantiation (UI), a perfectly acceptable logical construct. He instead believed that scientific models were universal generalizations (UG), which is neither true of any scientific model nor permissible in logic.

        For Wayne, 4/30/11, 8:04 pm, I read your post, and I think we were on the same wavelength. You point out that certain local conditions are necessary to produce a tornado, or presumably a cluster of tornados. Those conditions add to the background of global climate, according to a premise of climatology. However, a gap exists in the modeling between global and local processes. In particular, the current explanation for the cluster of tornados is the state of the SOI and El Niño/La Niña conditions. Whether this is considered variability in climate or a separate regional process, it is not predicted by AGW, so the current cluster is not confirming. Local phenomena are supposed to ride atop present day global temperatures, which are slowly turning into a climate event to invalidate the key AGW prediction of warming according to its climate sensitivity parameter. The fact that similar clusters occurred in the cooler climate of the past also tends to negate that confirmation.

    • “This model attempts to predict from subjective probabilities, which are explicitly excluded from science, as are all things subjective. ”

      Just out of curiosity, are you actually a scientist? Subjectivity and subjective probability are EVERYWHERE in science. When the wise men of, say, physics state the “confidence interval” on, say, Planck’s constant, they are using their subjective judgment about the reliability of the many different experiments that have produced data. I have now falsified your theory that there is no subjectivity in science!

      • Paul Baer, 5/2/11, 3:32 am, Tornado madness

        Satisfy your own curiosity and read. In particular, since you asked, start with my bio on Denizens.

        You are confusing science illiteracy with science. The confidence interval is not subjective, which was perhaps the major complaint statistician Arthur Dempster had with IPCC’s work. Here you don’t even have to read. Just watch his presentation on this blog in the thread Dempster on climate prediction.

        You probably don’t have any books on probability theory, but you might want to read the first chapter, The meaning of probability, of one of the best, Probability, Random Variables, and Stochastic Processes, by Athanasios Papoulis. This is the most elementary book on probability theory in the McGraw-Hill Series in Systems Science. Papoulis defines and analyzes four different definitions for probability. Here is his fourth:

        Probability as a Measure of Belief

        Probability is often used as a measure of belief that something might or might not be true; for example, “it is probable that X is guilty.” This interpretation of probability is different from the theory of probability as used in physical sciences. The reason is that it is a statement about a single event, and not about averages of mass phenomena. Furthermore, it is subjective. p. 14.

        By physical sciences he must have meant as distinguished from the social sciences, because otherwise this paragraph would be an understatement. You should read on from there, not just to satisfy your curiosity but to fill the gaps in your public statements.

        When you read an article with the over-worked phrase, “most scientists believe”, you are (a) not dealing with a fact (no one has surveyed all scientists on anything) and (b) you are not reading an article on science.

        Many scientists I have observed state a belief in God. In no way does that make God or Intelligent Design a part of science.

        When a scientist says, I believe I’ll have another beer, that does not make beer a part of science. Beer is, but for other reasons.

        Relying on a scientist’s beliefs is argument by authority. That is not part of science, either. When Carl Sagan predicted a nuclear-winter event from the oil fires of Kuwaiti, he was no longer being a scientist. When four-time Nobel Laureate Linus Pauling published Vitamin C and the Common Cold he created nonsense by ignorance of scientific principles. When MD Benjamin Spock, or logicians Bertrand Russell or Donald Kalish, marched to Ban the Bomb (remember the Union of Concerned Scientists and the Doomsday Clock, forerunners of the great Global Warming Consensus and Hansen’s T-minus 10 years to catastrophe?), they were speaking out of school. Being illogical is encouraged in politics, but invalid in science.

        In case you’re still curious, IPCC Assessment Reports on AGW contain a half dozen or so equivalent examples.

  19. Recipe for disaster?

    It seems to me that a tornado is like baking, in that you need to have all the right ingredients, mixed at the right time and right temperature(s) and other factors.

    Even if you have more of one or two ingredients of the recipe doesn’t mean you can make bigger cakes.

  20. The best way to make people offer their cash willingly is by scaring them.

    As long as this truth stands, the scare mongering continues.

  21. “Michael Mann: The fact remains that there is 4 percent more water vapor”

    Hmm, that sounds a touch high? Perhaps someone could explain that?

  22. Climate science has jumped the shark.

  23. The irony is Jose Bastardi and Piers Corbyn, two professional weathermen, correctly called and predicted the tornadoes more than a month ago. And they were fairly accurate, as they’ve always been. They used real world information, experience and honesty, to come up with these forecasts.

    This is quite unlike to the extreme AGW crowd who seem to attribute every weather event to AGW by tenuous connection, after the events happened.

  24. “So climate isn’t weather but weather is climate?”

    Climate is weather averaged over time.

    “Climate trains the boxer. Weather throws the punches.”

    • barry,
      And it is clear that the training is no different now than it has been.
      Weather is, has been, and will be, throwing dangerous punches at about the same frequency and strength.

  25. If climate changes, then weather activity will reflect, in some part, that change.

    The qualified climate scientists quoted above talk about possibilities, but all, including Trenberth, say that data on tornadoes is not sufficient to give a clear picture of trends in the past (nor are climate models able to project incidence for such small-scale phenomena). These are the cooler heads. Unfortunately, some activists and media need an ice pack.

    • Barry

      Check the wonkroom link above. Immediately after this tornado attack last week, Trenberth, Mann and Schmidt directly linked the tornadoes to climate change. This is completely against science and the reasons have been posted above by Watts, Bob Tisdale etc. And NOAA themselves clearly said that the tornadoes are due to ” spring ” and not climate change.

      The emphasis on the world ” Climate Change ” is AGW due to human released CO2, as defined by the climate science clique.

      Tornadoes are localised extreme weather events and these were predicted accurately more than a month ago by professional weathermen.

  26. Here’s an interesting post from Dr.Roger Pielke Junior, about the response he got from Peter Gleick and his rebuttal to that response.

    Gleick’s response is mostly obfuscation, innuendo and outright false statements. Pielke Junior politely rips him apart in the rebuttal.

  27. Venter,

    Gleick’s rhetoric goes too far. He knows better, but can’t help writing as an activist rather than a scientist – but it’s hardly unexpected behaviour from that publication.

    “Trenberth, Mann and Schmidt directly linked the tornadoes to climate change.”

    Regarding Mann’s quote in the Wonkroom article, he doesn’t mention tornadoes, so it’s not possible to know his views on whether the recent storms in the US can be directly linked to climate change. I very much doubt he would. The context he is advising is not the same as saying ‘global warming caused the tornadoes’.

    Presumably the Brad Johnson sent an email asking if the scientists thought the tornadoes were linked to global warming. As all these scientists have said at various times that one cannot (statistically) link global warming to any specific short-term event, I take their replies to be more general – indeed, they talk about context, rather than cause, and two of them specifically disconnect tornadoes with climate change (Trenberth & Schmidt).

    Unfortunately, we have neither the email nor the full replies, so their views are at the mercy of the wonkroom author, Brad Johnson, who has edited them. It goes without saying that the wonkroom is a political site, that the article is heavily politicised, and it should go without saying that it is not a reliable source for the views of any scientist. I repeat – the media and activists (Gleick is one) are prone to sensationalism. That’s not news.

    I agree with the criticism here that it is foolhardy (at best) to link any specific extreme event to climate change. This happens regularly enough on both sides of the debate – I wish the bright light of skepticism would turn equally on the myriad blogposts and media reports arguing a strong winter means global warming is in doubt. Well – this does happen in the blog wars, but each tribe continues to ignore the advice. Eventually, critical thinkers must filter that rubbish out or surrender to an online life of repetitious behaviour. I think that most in the climate blogosphere have done just that.

  28. (Surrendered to repetitious commentary in the climate wars)

  29. Hi Barry,

    Thanks, I get what you’re saying. But you know what, judging from past performance and the fact that these comments were made specifically by Mann and Trenberth in response to a query related to tornadoes, I’m afraid we can’t give them the benefit of doubt on acting reasonably. And as mentioned in the article these were replies to e-mails asking about the tornadoes. If he is twisting their replies and relaying only parts of them, all these three scientists have to do is to issue an immediate rebuttal and show the full text of the e-mails what they sent, if they had meant differently. I’d like to wait and see if they do that and take a bet that they won’t do that. I firmly believe that they said what they said as reported by Wonkroom, with full knowledge and intent to score political points by connecting these tornadoes to climate change. It was calculated, devious, shameless activist behaviour.

    I presume no innocence to any part of these scientists’ behaviour unless irrevocable documentary proof is provided.

  30. I wonder if any of the people linking ‘tornados’ and the like to ‘climate change’ at the instant they happen, realise that the general public may just see the total opportunism to promote their cause, and turn away in disgust.

    This happened with the earthquakes in Japan, and a number of retractions or rewrites of some comment s made. I’m thinking of an EU spokesman.

  31. Barry, those people are as likely to issue retractions as pastors would after linking a specific disaster to God’s vengeance.

    I don’t know who these people are and wonder if it’s worth caring what they say.

  32. Pat Robertson said that Haitians were punished by God, with the hurricanes, earthquakes etc.

    Not much different with parts of the media and climate scientists laying the blame on humans for the tornadoes

    Both are shameless evangelical statements which should have no place in a decent human society and certainly have no place in science.

    • You might expect that sort of thing from the more unscrupulous elements in the media and environmental activism.
      But for ‘respected’ scientists to even allude to it is a different matter entirely. They should be ashamed – if indeed they have any shame.

  33. Occam’s Razor. The chronology is simple. Barack Obama, after resisting calls to produce his birth certificate for years, caves in. Immediately after this decision, at least 19 tornados afflict Maryland and Virginia, killing hundreds. Be careful what you wish for, people, and don’t toy with forces you don’t understand. The science of curses is not ‘settled’…

  34. I have resisted commenting on this thread so far because the premise that the recent hurricanes were caused by a few added ppm of atmospheric CO2 emitted by human activity since the Industrial Revolution is so absurd it does not merit any comment.

    Max

  35. Anyone who has spent time forecasting severe weather knows that an optimum vertical profile of the atmosphere features warming in the lowest 150mb of the tropesphere accompanied with cooling in upper 200mb of the tropesphere. Warming near the surface and cooling aloft is indicative of the approach of deep cyclone. In this situation, winds ahead of the low back, but veer behind it. Again, looking at the vertical profile, one sees southeasterlies near the surface, but a veering wind component as one gains altitude. Combined, low level warming, high level cooling, and direction shear is indicative of a destabilizing atmosphere. Atmospheric stability can be measured by several indices (Showalter Stability Index, Lifted Index, etc..) . In short, stability is defined is really nothing more than whether air parcels are rising (instability) or falling (stability). There are many scenarios that bring on instability. Almost all are associated with large displacements of warmer air masses by colder ones. If one wishes to see how many of these scenarios are defined, find (if you can) the old TR-200 manual published by the late Col Miller (USAF). Much of the material is dated, but the physcics are sound. Retired NOAA research meteorlogist Charles Doswell also wrote many papers concerning the synoptic meteorlogy of severe thunderstorms.

    Yes, there are situations that produce summer time severe weather without the presence of large mid-latitude storms. In the Northern and Central High Plains, severe storms can occur because of high level speed convergence, upslope induced lifting (along the lee-side of the Rockier), or because of high level directional divergence (the so-called Northwest Flow thunderstorms). But these outbreaks lack the depth of tornadic activity that springtime storms bring. Also, it isn’t all that unusual to see the occaisonal winter time tornado, which is brought on by a deep pool of cold air aloft (500mb temp as cold as -40deg C). This is what occured at Altus AFB in Feb 1978. An F-2 tornado hit the base despite 38 degress surface temperature.

    If anything, we would see a marked decrease in spring-summer severe thunderstorms in a warming climate. The reasons are obvious – in a warming climate, an amplified Hadely Cell would keep the polar jetstream bottled up in the high latitudes. The dynamics needed for these storms would be missing. You need more than warm, humid air to produce severe weather.

  36. Attribution of individual events is a messy business, so messy in fact that it has no place in science. I would think it is only right to talk about probabilities and association of causalities. The big news this winter was the extreme flooding in Australia, and now, the big news this spring is this large tornado outbreak. Certainly they are both related to:

    1) The current La Nina
    2) The cool phase of the PDO

    Both were in place in 1974, the last time these two events (Australian flooding and large tornado outbreak in the US) occurred to such an extreme.

    Now, a case could be made that a changing climate (human caused or not) will change the nature of La Nina and the PDO, and certainly as the climate has changed and will change in the future these two natural cycles will change in one way or another. The point is, we have hardly enough data to say HOW those cycles will change with any given change in climate, and possibly we never will as those changes could be quite chaotic and may exhibit no clear trend. Tell me what climate model can accurately predict the next time a cool phase of the PDO and a strong La Nina will line up? If no climate model can predict that, then no attribution to AGW can be made to any of the effects related a strong La Nina and cool phase of the PDO.

  37. Then again, there are attribution studies such as this one:

    http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI3829.1?journalCode=clim

    Which seems to make a reasonable statistical case for a connection to increasing CO2 in the atmosphere and extreme weather events in the SE United States (though not specifically tornadoes).

    • These changes would increase the likelihood of both strong anomalously wet and dry summers over the SE United States in the future, as suggested by the IPCC AR4 models.

      “Anomalously wet AND dry?” Hmmm…

      What are these guys feeding these models?

      Max

      • manacker,
        What ever they are feeding their models, it is clear what they are feeding us.

    • “The results show that the NASH in the last 30 yr has become more intense, and its western ridge has displaced westward with an enhanced meridional movement compared to the previous 30 yr.”

      So the PDO makes the NASH move? The PDO does a lot of things, many not understood yet, but the PDO is not CO2.

  38. Joe Romm has an atypically sensible post on tornadoes-climate: “the jury is out”

    http://climateprogress.org/2011/05/02/tornadoes-extreme-weather-and-climate-change/

    • Romm makes a post that is not spittle-flekked, so this is big news.
      Now his systematic misrepresenttion of the facts and his grasping at hysteria is rather typical, but even Joe seems to realize that if he says the sort of stuff his pals have been saying- how the denilaist scum bible tumping breeders got what they got ‘cuz they don’t *believe* in AGW is a bit over the top. So for once Joe’s blog lived up to its name. Joe made some progress, if not in climate at least in manners.

  39. “The collision of air masses of widely differing temperatures and humidity can create violent storms—the Midwest’s recent rash of disastrous tornadoes, for example.”

    from:
    Another Ice Age?
    Monday, Jun. 24, 1974

    http://www.time.com/time/magazine/article/0,9171,944914,00.html

  40. Collide-a-scape has a good post reflecting on the recent coverage of the tornado-climate nexus

    http://www.collide-a-scape.com/2011/05/04/on-revkin-romm-and-the-zero-sum-climate-debate/

  41. Willis Eschenbach talked about the ” precautionary principle ” canard with respect to climate science and catastrophic events, in his post at WUWT almost 18 months ago

    http://wattsupwiththat.com/2009/12/31/climate-caution-and-precaution/

    Neither the Governments nor AGW advocating scientists nor columnists like Keith Kloor and Andy Revkin contributed anything meaningful as a solution to try and avoid problems due to extreme weather events and make people’s lives and property safer, limiting damage. They have all pontificated about Climate Change and need to act before it’s too late, hand waving a lot and predicting doomsday. They will continue to behave the same way from their high horse, regardless of reality.

    As far as Keith Kloor is concerned, look at this earlier post of two days ago his about catastrophic events and public being swayed.

    http://www.collide-a-scape.com/2011/05/02/can-climate-catastrophe-sway-the-public/

    See the comment numbers 1-6 and weep. That’s the attitude of this guy. He’ll talk only to James Hansen and Co and will not talk to a single ” skeptic “. That’s his idea of a fair dialogue.

    He’s not interested in solving any genuine issues or truth going to the root of any problems. He just wants to propagate a particular viewpoint of the AGW crowd. He’s of the camp that seems to believe that the problem of the climate science is ‘ communication ‘ and ” swaying the public ” and can’t see that the problem is rotten science and dishonesty.

    • Kind of ironic that Gavin finally gave up the Hockey Stick right there at Keith’s, and he still doesn’t see it.
      ==========

      • When I saw Keith arrange a dialogue between Gavin and Steve, I thought, hey, this guy is a miracle worker. But he’s just another alarmist. More aware than most, I’ll say.
        ===========

  42. Pooh, Dixie

    Above, Mike Smith of Meteorological Musings makes a good case that, on the contrary, prediction and warning of tornados are well advanced.

    Let me suggest that the usual attribution babble of “global warming” is more an example of an “Availability Cascade” (Kumar and Sunstein, 2007) than it is of “climate change”.

  43. NOAA has a new analysis on the recent tornadoes, its very well done

    http://newspoliticsecon.gather.com/viewArticle.action?articleId=281474979303380

  44. So, how is a tornado formed?

  45. “You never want a serious crisis to go to waste”

    The boys lose some of what is left of their scientific credibility.

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