People are asking me: Is the recent spate of tornadoes caused by global warming? The usual answer to that question is that you can’t answer the question because a tornado is not caused by climate … it is cause by weather … and global warming (which is real, and which is cause by humans) is climate change.

However, that is not really the best answer to the question. Ultimately, I want to propose an analogy for how to think about this question, but first, a stab at a good answer, which if modified could probably be improved:


Question: Is Anthropogenic Global Warming the cause of the current spate of deadly, powerful, and numerous tornadoes?

Answer: Eventually we’ll have enough data to answer that question, but the answer will not refer to a given tornado or even a given tornado season. Rather, it will refer to the relationship between two major climatic factors which are potentially influenced by global warming.

The first is the total energy available to do things like producing thunder storms, including the tornadoes they spawn, as well as other weather events. Much of that energy comes broadly from the tropics where excess energy from the sun builds up and is then redistributed through oceanic and atmospheric currents, and more directly from sea surface temperatures in the Gulf of Mexico. The warmer the surface of the gulf, the more moister and energy going into north and northeast trending air masses that is a key component in making these storms. In the end, it is impossible to imagine a scenario in which there is not more storminess of some kind, somewhere, because storm fronts are this energy dissipation manifest as weather. Whether that tuns out to be more rain, more thunderstorms, more severe thunder storms, or more tornadoes is as yet unclear.

The second is a bit more obscure: This is a change in the way air masses are divided up on our planet. Climate systems are ultimately driven by the sun’s energy, and in particular by the fact that there is excess energy at the equator which then moves towards the poles (while at the same time dissipating off the planet at the upper edge of the atmosphere). This is a simplification: These air masses are organized as giant rotating donuts surrounding the planet. The first set of donuts are on the equator, and rotate (as in twisting, not orbiting) in opposite directions, the northern one twisting upwards at the equator and downward north of the equator, the southern one doing the opposite. The next set of donuts out, north and south, twist in the opposite direction. And so on. There are several different such donuts.

The boundaries between these giant donuts of air are highly active regions. The reason for this is way beyond the scope of this post, and requires calculus so you’ll have to take my word for it. Let’s just say that the phenomena we call “jet stream” is the result of interactions between the giant twisting donuts of air.

The donuts are far from perfect. Those closest to the equator are very consistent and always present and fairly obvious, but as we work out from the equator they become less clearly defined. Even the distinction between them is less and less clear with increasing latitude, and as the distinction becomes less clear, the “jet streams” become less likely to occur. Now, and again this is an oversimplification, imagine that each giant twisting donut as you go from the equator to the poles is colder and dryer. This means that at the margin of two donuts, where warm moist and cool dry air contact, there will be storms, especially where the atmospheric machinations generate low pressure systems. This is where storms are born. Now, imagine taking the warm and wetness of one of these donuts and pushing it up against the coldness and dryness of a rotating donut at a much higher latitude, skipping an entire donut. The contrast between the two air masses would be much greater than normal, and thus the storms would be much more frequent and stronger than normal.

That’s one way to get a stormy year: Take two donuts that are normally distinct and combine them into own: Thus, the contrast between the southern margin of that air mass and the next air mass to the south will be greater, and the storms stronger and more numerous. That is what is happening in the US now. Those living in norther states are experiencing a cold spring and early summer, and the southern edge off this air mass is contacting a very warm and moist air mass, and this contact zone is where the severe thunderstorms and tornadoes are forming.

There are some models that suggest that the breakdown in distinction between these air masses is caused by anthropogentic global warming (or, really, any global warming but it happens that our current warming is anthropogenic). At the same time, we know that the sea surface temperatures in the Gulf are high, also because of AGW. These two things together would be the cause of an increase in frequency and severity of storm fronts, the thunderstorms that form along the front, and the tornadoes.

There could be other explanations for an increase in tornadoes. For example, the frequency of thunder storms may be higher because of AGW, but there is some other reason more storms are producing twisters. But again, as per the answer given above, this is the sort of thing that will be figured out in due time with more data and analysis.

Now, the analogy. We can’t say one tornado or another tornado is caused by your selfish and inconsiderate CO2 belching behavior. Which is important because you would prefer to not be blamed for the massive destruction and whispered death we are experiencing across this country right now. But let’s assume that the two factors discussed above are true: The breakdown of the donuts and the increase in sea surface temperatures in the gulf. How do we link, and is it even possible to link, global warming to a tornado via these mechanisms?

The analogy is robbery. Robbery is where people take other people’s stuff. Maybe they rob a store or a bank, your house, or they mug you on the street. It is known that this kind of economic crime increases in frequency when the economy is bad and unemployment is high. So, does this mean that if you get mugged that the cause of the mugging is the economy? No. A certain amount of robbery happens anyway, so you can’t say that a given robbery is caused by the economy (indirectly… obviously the economy is not robbing you, some dude is). Not everyone becomes a robber when the economy goes in the toilet, nor does robbery become randomly assigned among the populous as a novel behavior. There is number of reasons why a particular robbery happens, including the role of the victim, who must, after all, be in the wrong place at the wrong time, or have some stuff to get robbed, etc.

A tornado is less likely to happen if the terrain is not flat or the season is not right. Tornadoes will destroy more property and klll more people if more people are settled on flat landscapes down-wind, as it were, from the Gulf. And so on.

So you can’t say a given robbery or tornado was caused by higher unemployment or AGW. But if you look at a graph and see a rise in frequency of either kind of event, you could attribute that bulge in the data to these causal factors.

In the end, in my opinion, the answer will be yes. Tornadoes or other storm phenomena including hurricanes will have increased in either frequency and energy level or both, and possibly the extent to which they reach northern latitudes, because of anthropogenic global warming. The current debate (to the extend that it is a debate rather than senseless mud slinging) involves scientists on one side saying “Yeah, probably, it makes sense, and the data are starting to show this” and denialists on the other side saying “you can’t say that” because of sophistic pseudo-philosophical reasons.

Tornado and hurricane frequency (and other features) vary from year to year across quasi-cycles that are less than a decade long, so it is not unexpected to have a few bad years followed by a few years that aren’t so bad followed by a few years that are bad again. This is especially true of the most severe events. For example, the strongest hurricanes and the strongest tornadoes are so rare that counting them up annually and looking for trends over the years will probably not be very useful. We may be having a bad period with more tornadoes, and more powerful (and deadly) ones, right now. The question at hand is this: Are the bad years getting worse, and are the not-so-bad years getting bad, or are the bad periods getting more common? To address these questions empirically it will be necessary to have at least a few decades worth of good data under conditions of global warming. We probably have those data now, or almost so. This question will be settled by reasonable people reasonably soon.

____________________

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Comments

  1. #1 Dave X
    May 25, 2011

    I’d focus on the ‘spate’ part of the question–a single tornado is not a spate by itself, and clearly identifying and attributing an individual spate, or even an individual tornado, is pretty fuzzy. Post storms, our NWS WFO drives around and tries to count the tornado paths and decide whether or not they are connected to each other (one tornado) or not (two tornadoes).

    If a card deck is stacked (e.g.: by removing an AKQ&J), would a poker player’s losing run be due to the stacking?

    Refining the question into “Are tornado frequency or intensity affected by warming?” starts towards developing questions that can be answered with enough science, statistics, and research.

    I think it is obvious that storms and tornadoes must be affected in some manner by changing climate, but by how much and the mechanisms behind the changes are interesting questions. They may not answer a particular’spate’ question, but they’re ultimately more useful.

    Is AGW stacking the deck or loading the dice? Yes. Will it cause a spate of lost hands? It depends.

  2. #2 Les Johnson
    May 25, 2011

    Its unlikely that tornadoes in particular, or extreme weather in general, is caused by a warming climate.

    While it has warmed globally in the last century, there is very little to indicate that there has been a concomitant increase in extreme weather.

    In the case of tornadoes, there has been a slight decrease in the strongest US tornadoes over the last 50 years.

    From the NOAA:

    http://lwf.ncdc.noaa.gov/oa/climate/severeweather/tornadoes.html#history

    Globally, hurricanes are at near 30 year lows.

    http://www.coaps.fsu.edu/~maue/tropical/global_running_ace.jpg

    There has been no increase in the US of peak flood height, drought, or severe storms. Or even snow storms, as the 50s had more. Though the last 10 years has seen a decline in cold events.

    Of course, in the US, there has been no great amount of warming, with only 1.2 deg F of warming since 1895. Since 1998, there has been nearly 10 deg F/century of cooling. (against the 1895-2000 average).

    http://www.ncdc.noaa.gov/oa/climate/research/cag3/na.html

    So, to answer your question, using several decades, or over a century, of empirical data as you suggested, shows no trend in storm intensity, either in number or strength. If anything, there is a slight decline. In hurricanes, a significant global decline. In the US, the hurricane trend is an insignificant decline.

  3. #3 Thomas F.
    May 25, 2011

    There may be merit to this deck of cards analogy.

  4. #4 Baron M.
    May 25, 2011

    Dave X, good points but I am not sure how it is different than the original post.

  5. #5 Windy City Kid
    May 25, 2011

    The National Oceanic and Atmospheric Administration provides an excelent overview of the current worldwide consensus on on hurricanes/typhoons as related to climate change.

    http://www.aoml.noaa.gov/hrd/tcfaq/G3.html

    I would also recommend that you guide your readers to their state climatologists for information as I have found mine to be very responsive to questions I’ve had on climate.

    http://www.stateclimate.org/

  6. #6 Robert Rhodes
    May 25, 2011

    Extremist Republicans and Christians are predictable AGW tornadoes and other catastrophes.

    “GBRWE 5/8 – 14/11 ‘regular’ for global warming predictions: sports, rainfall, tornadic, hurricane, and stellar ecosystems with tectonic quantities … by Robert Rhodes, The “Ozonator” … B1. Weeks’ Reporting Period of GBRWE 5/8 – 14/11. … DEQ-ORMs and their ExxonMobil – Koch Bros’s phony, global warming science (aka AGW – anthropogenic global warming) … from American extremists’ holy environmental racism from global warming, the still Brain-dead Ronaldus Magnus Model of Hatred and Greed & T-bags – tornadoes, blizzards, torrential rain, and other forms of lightning or something uglier will develop in titanic swathes within 2 weeks – a). Earth: Toledo, Ohio – Gary, Indiana – Cedar Falls – Rapid City – Butte”.

    “GBRWE 5/22 – 28/11 ‘regular’ for global warming predictions: sports, rainfall, tornadic, hurricane, and stellar ecosystems with tectonic quantities … by Robert Rhodes, The “Ozonator” … B1. Weeks’ Reporting Period of GBRWE 5/22 – 28/11. DEQ-ORMs and their ExxonMobil – Koch Bros’s phony, global warming science (aka AGW – anthropogenic global warming) … from American extremists’ holy environmental racism from global warming, the still Brain-dead Ronaldus Magnus Model of Hatred and Greed & T-bags – tornadoes, blizzards, torrential rain, and other forms of lightning or something uglier will develop in titanic swathes within 2 weeks – a). Earth: Austin, Texas – Wichita Falls, Texas – Norman, Oklahoma – Waterloo, Iowa – Wausau, Wisconsin”.

  7. #7 Doug
    May 25, 2011

    I like these analogies and would very much like to borrow them for my intro met course. The relationship between probability and causality can be kind of a tricky one to explain, especially to students who’ve never really had to deal much with statistical reasoning. One quibble; the midlatitude ‘donut’ is not really a donut — it’s more like a cake mixer, with wave cyclones as the blades, guided by planetary long waves.

  8. #8 Jack
    May 25, 2011

    More bs from climate scienotlogists.

  9. #9 Lyle
    May 25, 2011

    This year the tornadoes are hitting cities not rural areas. Consider Joplin the tornado was 6 miles long by 3/4 of a mile wide. In terms of the county were it occurred it hit less than 1% of the county’s area. Move it north or south 10 miles and the damage would be less. An EF-5 in the country will be more like the damage in OK yesterday. In addition the storms are a bit further east, not in western kansas where you really bother only crops and cows. Given a guesstimated return period of ef4 and ef5 tornadoes in the mid continent of between 5000 and 10000 years (defined as a given spot being hit by 2 of them not nearby but the exact same spot).
    It was noted that 15 mi west of Joplin in KS the tornado had not yet formed, and the tornado did not leave the east end of the Joplin area.
    Consider the Weather Channels It could happen Tomorrow were it put something like the Tuscaloosa tornado, thru downtown Dallas. You could have a 30 mile by 1 mile stretch of total destruction (looking at the hospital one gets a hint of how a skyscraper would do during a tornado of this magnitude).
    So in summary the total number is up but not by that much, but the tornadoes have struck cities not rural areas this year.

  10. #10 Greg Laden
    May 25, 2011

    Lyle, your guesses and ‘data’ are not very accurate or correct. F5 tornadoes are very very rare. It is simply not this year’s tornadoes happen to be hitting cities by random chance.

    Doug, for the purposes of the present short blog post, the Earth is a spherical cow!

    At least I avoided mentioning refrigerators. But this could be done with a Tyvek (sp?) analogy as well, where moisture buildup = stormy weather.

  11. #11 Greg Laden
    May 25, 2011

    Les: Yes, long term and medium term fluctuations may explain what we are seeing, however they may also just mask other trends.

    The problem with the data you point to is that it excludes the last several years.

    The thing is, increased storm activity of some kind is expected with a warmer earth. Increase mid-latitude storminess such as t-storms and tornadoes is expected under certain models. And, medium term trends such as el nino la nina along with observational bias (tornadoes are small and in pre-radar days often went undetected) make this kind of modeling hard.

  12. #13 Dave X
    May 25, 2011

    Baron M — I do mostly agree with Greg. However in his reformulation of the “people are asking me…” question, I’d more strongly highlight the distinction between individual events and differences in the populations.

    I’d also split the AGW bit out to make it less of a complex question: “Are you asking if climate can influence the frequency or intensity of storms and tornadoes?” Sure — changes in circulation patterns or energy flows can mess with where, how big, and how often the storms are, and that could in turn change the number and strengths of tornadoes.

    As for the robbery analogy, it’s a bit unclear which way the crime rate should go when the economy tanks. Google “crime rates economy” Maybe if many are poor and unemployed, they don’t have much worth robbing and they might guard what they do have more. Tying that uncertain causal chain to the next link, that being the effect of voodoo economics on the economy, makes it harder to justify the more tenuous combined answer of, say, cheap labor conservative economics causes more crime.

    We should encourage folks to ask the right questions.

  13. #14 Eric Lund
    May 25, 2011

    Lyle @9, it’s true that tornadoes have been hitting cities this year, but that’s not the whole explanation. There have been far more tornadoes this season than normal; April 2011 saw a new monthly record for tornado counts. That includes tornadoes of all strengths; the Tuscaloosa-Birmingham tornado was rated EF4, not EF5. Wikipedia’s list of F5/EF5 tornadoes includes 57 with that rating, four of which have occurred this year. Having four F5/EF5 tornadoes in the same year, or three in the same day as happened last month, is not unprecedented (the 3 April 1974 Super Outbreak produced six F5 tornadoes), but it certainly is unusual.

    We can’t say for sure that there is a trend, mostly because our ability to detect tornadoes is better than it ever has been, and partly because we now know that tornadoes occur in places other than North America, a fact that was not fully appreciated when I was a kid. All of the known F5/EF5 tornadoes have occurred in North America (one in Manitoba in 2007, the rest in the US), but there are several tornadoes in Europe and one in Australia listed on the Wikipedia page as suspected F5s.

  14. #15 Greg Laden
    May 25, 2011

    Dave,I’m pretty sure the crime rate thing is an excellent case fur further study. As I understand it, there is a demonstrable link between crime rates (for certain crimes) and economic conditions across both space and time. However, long term crime rates so not correlate because there are other overarching factors. It would be like comparing habitability of Arctic regions across temperature changes and including the period after the sun expands and engulfs the planet. There has been a lot of press over the last couple of years “debunking” the crime rate thing, but it is not about the short term common-context shifts in crime rate but rather comparing across different eras. Using the cros-era comparison to calibrate causal relationships is not valid.

  15. #16 Greg Laden
    May 25, 2011

    … but enough about crime rates …

    Two more quick comments: First, I don’t want to split out AGW for the very simple reason that this is the interesting and relevant question and, in fact, is the question people have been asking me. But it does make it a bit more difficult.

    Second point, until there is a way to dig up fossil tornadoes (and get meaningful numbers) as we can do with tsunamis and hurricanes, the fact is that almost all of our tornado data, even the pre-radar data (which could be used with proper sampling techniques) is POST global warming effect. This is true for all storm types, for the good data. Global warming as an effect is not correlated with scientists realizing that there is a greenhouse effect or members of congress suddenly (sort of) getting it. There are probably effects that to back to before the production of the movie Wizard of Oz! (Not necessarily any particular effect.)

    Having a lot of tornadoes in the 70s does not mean that global warming is not a factor. The 70s is well within the era of increased carbon in the atmosphere.

  16. #17 vasio n. martianin
    May 25, 2011

    … it’s more like a cake mixer, with wave cyclones as the blades, guided by planetary long waves.

    like the man said, a donut :)

    in terms of climate change, what we’re seeing is just the tip of the iceberg.

  17. #18 Robert Rhodes
    May 26, 2011

    With more condolences to the victims –

    More money for 33% Judge Crater-ratings Limbaugh and his willing accomplices’s AGW disaster plan is to make money off of the dead, dying, and damaged local yokels from their municipal projects.

    “Rush Limbaugh … “Screw the moderates … On his own personal investments: “… My investment portfolio is very conservative with lots of municipal funds … I love what I do” (“Rush: Democrats Are a ‘Bunch of Cowards’”; newsmax.com, 2/8/06).

    Costing EIB coli nothing to entertain his AGW locusts, “Amazing Line from Joplin, Missouri … May 25, 2011 … RUSH: Joplin, Missouri.  This is Dave. … CALLER:  I’m doing well compared to most people really.  Me and my family, we were blessed … The people that are downtown, they were the ones that really got hammered on. … somewhere around 3,000, 3,500 buildings, and probably a good 30 to 50% of the town got leveled. … But for the most part it looks like everybody’s doing pretty good … RUSH:  That’s amazing.  Did you hear that?  Everybody’s doing good, all things considered. … heartland attitude, attitude that makes the country work. …  Appreciate the call, Dave” and “Impotent Democrats … September 9, 2005 … RUSH: … We need to know right now before any future disaster hits the nation your solution to any future … tornadoes for every town, country, and state in America. … what the hell is your plan? … Their whole philosophy and ideology is on display here as an utter and total failure” (the old, ugly and evil Rush “LABI” Limbaugh with Hannity/Noory extremist Republican and Christian outlets for legally killing thy neighbors with willing accomplices and sham brides, EIB coli, and another GOP human trafficker trying to harvest more Americans faster than Esso-Koch; losing megabucks unable to sell NRA gun, erection, hair-plug, and designer toxic scent products; rushlimbaugh.com). With their AGW catastrophes creating open space and discount estate sales, “”I don’t think American people want shared sacrifice,” John Watson, CEO of Chevron, said at a Senate Finance committee hearing today. “I think they want shared prosperity.” “I’m not out of touch at all,” said Rex Tillerson, CEO of Exxon Mobil” (“Do Americans Want ‘Shared Sacrifice? Big Oil Exec Says No”; By MATT JAFFE and ARLETTE SAENZ; abcnews.go.com, 5/12/11). “The threat of catastrophic global warming the “greatest hoax ever perpetrated on the American people,” … Dr. Crichton urges calm: “I suspect that people … will … enjoy more wilderness than we have today. ….” … Kyoto-like policies harm Americans, especially the poor and minorities” (“Climate Change Update”; Senate Floor Statement by U.S. Sen. James M. “Evil” Inhofe(R-Okla); inhofe.senate.gov/pressreleases/climateupdate.htm, January 4, 2005).

  18. #19 Les Johnson
    May 26, 2011

    Greg: your

    The problem with the data you point to is that it excludes the last several years.

    No, all the links I gave were up to date. The tornado data is up to date (2011), but you need to go to the bottom of the page. This will get you there too.

    http://lwf.ncdc.noaa.gov/sotc/tornadoes/2011

    The other 2 references were up to date as well, with 2011 YTD data in the ACE index, and 2010 data in the temperature data. As it was annual data, it is not possible to have 2011 annual temperature data. If you want though, you can filter that data to YTD 2011, or seasons (JFM) for 2011. But 2011 data is in all the links I gave you.


    The thing is, increased storm activity of some kind is expected with a warmer earth. Increase mid-latitude storminess such as t-storms and tornadoes is expected under certain models. And, medium term trends such as el nino la nina along with observational bias (tornadoes are small and in pre-radar days often went undetected) make this kind of modeling hard.

    I will take empirical over modeled. And empirical data shows no increase in storms. But, several models also show a fall in storm numbers with a warming world.

    (Zahn, M., and H. von Storch. 2010. Decreased frequency of North Atlantic polar lows associated with future climate warming. Nature, 467, doi:10.1038/nature09388.)

    Much evidence of historical records shows increasing severity of storms in a COOLING climate.


    Intense storm activity during the Little Ice Age on the French Mediterranean coast
    L. Dezileaua, P. Sabatiera, b, P. Blanchemanchec, B. Jolyd, D. Swingedouwe, g, C. Cassoue, J. Castaingsa, P. Martinezf and U. Von Grafensteing

    On the subject of tornadoes, lets refer to the experts. NOAA has this to say:

    With increased national doppler radar coverage, increasing population, and greater attention to tornado reporting, there has been an increase in the number of tornado reports over the past several decades. This can create a misleading appearance of an increasing trend in tornado frequency. To better understand the true variability and trend in tornado frequency in the US, the total number of strong to violent tornadoes (EF3 to EF5 category on the Enhanced Fujita scale) can be analyzed. These are the tornadoes that would have likely been reported even during the decades before Dopplar radar use became widespread and practices resulted in increasing tornado reports. The bar chart below indicates there has been little trend in the frequency of the strongest tornadoes over the past 55 years.

    The NOAA also states, in several reports, that there has been no increase in Atlantic storms. (Soden and Landsea)

  19. #20 Les Johnson
    May 26, 2011

    Greg: your

    Having a lot of tornadoes in the 70s does not mean that global warming is not a factor. The 70s is well within the era of increased carbon in the atmosphere.

    Except of course, temperatures were declining in the 70s, globally. In the US, from 1930 to 1980, the trend was -2 deg F per century.

    So, yes, we can definitely say that global warming was not a factor in the 70s storms.

  20. #21 Stephanie Z
    May 26, 2011

    Of course, Les, that cooling has been in winter, not tornado season. It also disappears if you go back just another couple years in your graphing. So you can find a date range you like. Big deal.

  21. #22 Greg Laden
    May 26, 2011

    Les, I’m pretty sure you are missing the point of my post. I’m proposing a way to deal with a question, not an answer. I’m also suggesting what I think the answer may end up being. You are focusing on the latter as though it was a firm conclusion, though it is not.

    When the data suck, I’ll take modeling over empirical data any day. And so would you, I suspect, but perhaps only under selected circumstances.

  22. #23 Robert Rhodes
    May 26, 2011

    “Posted by: Les Johnson | May 26, 2011 6:44 AM” is criminally incorrect about ACE.

    “A). … 4). ACE-hole gate (hurricanes) is the lies, fraud, and malfeasance of publicly funded research by extremist Republican and Christian approved “scientists”, Florida State University’s Dr. Ryan Maue and NOAA’s Dr. Chris Landsea based on generating Accumulated Cyclone Energy (ACE) for 2010 to profit from ignoring real science, real numbers, and real global warming catastrophes. … Son of Ace – after much searching, it was found that “ACE” is primarily the artificial hurricane and 90% exclusive numbers of Dr. Ryan Maue, Florida State University and NOAA’s Dr. Chris Landsea with “violence against … scientists” from their extremist media outlets” (“GBRWE 10/24 – 30/10”s Extreme Planetary Warnings for Earthquakes, Volcanoes, and Solar/Terrestrial Flares from Human Activities”; Robert Rhodes, Supplemental; GBRWE 10/24 – 30/10, 10/23/10).

  23. #24 Les Johnson
    May 26, 2011

    Stephanie Z

    your

    Of course, Les, that cooling has been in winter, not tornado season. It also disappears if you go back just another couple years in your graphing. So you can find a date range you like. Big deal.

    No, the link I gave to NOAA temperatures is annual temperatures, not winter.

    Yes, the trend goes to a quite small +1 deg/century if I go back to 1895. If I go back to 1930 (50 years from 1980), the temperature trend is negative.

    In other words, the US was cooling during the last large outbreak of tornadoes in the 70s, and had been for 50 years.

  24. #25 Stephanie Z
    May 26, 2011

    I’m well aware of what information you gave, Les. You didn’t think I was only going to look at that when you gave me a link, did you? Winter was the only season in which the cooling trend held up. It didn’t hold up at all if the start year wasn’t in a La Nina.

  25. #26 Les Johnson
    May 26, 2011

    Greg: your

    Les, I’m pretty sure you are missing the point of my post.

    No, I am pretty sure I am not.

    I’m proposing a way to deal with a question, not an answer. I’m also suggesting what I think the answer may end up being. You are focusing on the latter as though it was a firm conclusion, though it is not.

    I never made a firm conclusion. I use words like “could”, “might”, “suggest” and “currently”. I also don’t presume to know what the answer might be, just because the data is not conclusive. Currently, the data suggests that the small amount of warming in the 20th century did not contribute to an increase in storm severity.

    I have given hard data to support my point, you have not.

    When the data suck, I’ll take modeling over empirical data any day. And so would you, I suspect, but perhaps only under selected circumstances.

    A surprising stance for a scientist. I prefer hard data myself. If the data does not match the models, then I throw out the model, not the data. I will check the data, to ensure no errors are in the dataset. If none are found, I blame the model, or the modeler.

    ps- I work in modeling fluids and fluid flows.

  26. #27 Les Johnson
    May 26, 2011

    Greg:

    I see you allow libelous, false and malicious postings on your site.

    Do agree with Rhodes?

  27. #28 Les Johnson
    May 26, 2011

    Stephanie: You did not look at the data I gave you. The trend in spring (Mar-Apr-May)1930-1980 is also negative.

    All the seasons have negative trends 1930-1980.

  28. #29 Les Johnson
    May 26, 2011

    Stephanie: your

    It didn’t hold up at all if the start year wasn’t in a La Nina.

    Actually, it would hold up less if the start year was a la Nina. la Nina’s are cooler. A cool start would tend to have a positive slope (warming).

    Starting in a el Nino, on the other hand, would tend to give a stronger cooling trend.

    But, statistically, a 1 to 2 year ENSO event would not greatly affect the over all trend in a period of 50 years.

  29. #30 Stephanie Z
    May 26, 2011

    Actually, La Ninas are measured by water surface temperature, not inland temperatures. And measuring 1910-2000 gives you a rising temperature. W00t. The point is that you’re cherry picking years you like that have no plausible reason to be reference years. Looking at the full range of data available shows a distinct warming trend.

  30. #31 Greg Laden
    May 26, 2011

    Les, I’m not making a point that requires hard data. You, on the other hand, are making a point that requires taking my post and recrafting it as a straw man that you can then make your point with. Why is that?

  31. #32 Les Johnson
    May 26, 2011

    Greg: your

    Les, I’m not making a point that requires hard data. You, on the other hand, are making a point that requires taking my post and recrafting it as a straw man that you can then make your point with. Why is that?

    You are trying to make a point, that does require hard data.

    Let me quote you:


    Question: Is Anthropogenic Global Warming the cause of the current spate of deadly, powerful, and numerous tornadoes?

    You are asking the question; is warming is causing the rash of tornadoes? I provide hard data that suggests, for the time being, no.

    You, on the other hand, have provided no data at all to support your point of view.

    Why is that?

    A scientist’s oxygen is data. But you have said that you will take models over data.

    Why is that?

    Of course, I have shown models that suggest the opposite of your position. You have not replied to this.

    Why is that?

    I have also asked you about the libelous and false allegations made by Rhodes, but you ignore it.

    Why is that?

  32. #33 Les Johnson
    May 26, 2011

    Stephanie: your

    Actually, La Ninas are measured by water surface temperature, not inland temperatures.

    To be more precise, ENSO is measured by central Pacific SST. But ENSO affects the global temperature. el Nino’s warm the globe, la nina’s cool it.

    And measuring 1910-2000 gives you a rising temperature. W00t.

    Pity I was referencing the 1930-1980 period, to cover the increase in tornadoes stated by Greg, in the 70s. This period was cooling. Ergo, warming was not responsible for the tornadoes in the 70s.

    WOOt.

    The point is that you’re cherry picking years you like that have no plausible reason to be reference years. Looking at the full range of data available shows a distinct warming trend.

    There are cycles, Stephanie. They go up for a few decades, then they go down. The normal reference range for climate is 30 years. I have given you a 50 year cooling period inside the cycle. A cycle, I might add, that is part of gradually increasing temperature record.

    You are also ignoring that the fact you were wrong in stating that it was only a seasonal temperature decrease 1930-1980 in the US. It was a general cooling period, not seasonal.

    In other words, you were fibbing in saying that you looked at the data. You didn’t. Fess up. C’mon, confession is good for you.

  33. #34 Greg Laden
    May 26, 2011

    So, Les, are you saying that there is no “global warming”? Is that your point? Why do you say that?

  34. #35 Les Johnson
    May 26, 2011

    Greg: your

    So, Les, are you saying that there is no “global warming”? Is that your point? Why do you say that?

    No Greg, I did not say that, please read the post immediately before yours.


    A cycle, I might add, that is part of gradually increasing temperature record.

    Note the word “increasing”. What I am saying, is that record points to an increasing temperature since the little ice age, with a large amount of variability. At least in the US, severe storms seems to accompany the dips in the cycles.

    My point is that the small amount of warming we have seen in the last 100 years (ok, 112 years), is likely not responsible for the rash of tornadoes this year. Simply put, its because there is no upward trend in severe storms.

    Once more, I ask, Greg, why do you allow false and malicious posts on your site by Rhodes?

    Why do you, as a scientist, believe in man made models over empirical data?

    Why do you not provide data to support your view that warming causes an increase in storm intensity?

    Why do you believe only in models that support your view, when many models suggest the opposite?

  35. #36 Les Johnson
    May 26, 2011

    Inquiring minds want to know, Greg…

  36. #37 Greg Laden
    May 26, 2011

    Les, are you specifically suggesting that Rhodes not be allowed to comment here?

    I haven’t read his comments. I just noted that there are no links to climate denialist sites in them. If I’ve missed that, let me know.

    Otherwise, if you have a problem with what he’s said, go right ahead and duke it out!

    “Why do you, as a scientist, believe in man made models over empirical data?”

    First of all, drop this “as a scientist” shit. That’s a load of crap. Drop it now or you’re gone.

    Regarding empirical vs. models: Are you claiming that the tornado data are reliable and posess century long homoscedasticity? I was under the impression that they don’t. I was under the impression that the tornado data kinda sucked. I’m starting to rethink that assumption, realizing that it may be wishful thinking and that it may be useful.

    In any event, AS A SCIENTIST I would not base much on sucky data. Models, on the other hand, can be rather useful. I’m not sure why, AS A SCIENTIST you would think otherwise.

    I’ve been assuming that you are the Les Johnson at NASA, have I got that wrong? (Or am I thinking of someone else).

    to be honest, Les, I’ve been giving your comments less attention than they probably require because I’ve got a lot of distractions here. (no child care for several days, everybody has a fever, and I think there are these dogs that are not normally here … ). I will read back over your questions.

    But again, I’m not trying to make the case that AGW has increased tornadoes. I’m trying to make an argument that the disconnecte between weather and climate is not an appropriate excuse for global warming, and it has been used as such.

    However, my gut feeling is that storminess in general is increased by AGW, and has been, but that the nature of variation inherent to the system makes it impossible to demonstrate this with the usual approaches in anything like real time. And this is, in fact, a situation where models may be the best way to go. For reasons I’ve stated several times.

  37. #38 Stephanie Z
    May 26, 2011

    I can see your confusion, Les, but the comment about winter refers to your 1998 to the present statistics. But nothing you’re saying tells me why you want to start a temperature chart in 1930 to compare to a tornado chart that starts in the 50s or why you would look at year-round average temperature to talk about a spring-summer phenomenon. Or why you would think national average temperature is so terribly important when we’re talking about temperature differences between clashing air masses.

  38. #39 Robert Rhodes
    May 27, 2011

    Poor Les is less – either do your homework or get another corporate rubber stamp at the next extremist media echo seminar. Dear crimes against humanity Johnson, the web has many examples of my correct AGW predictions. It is bad when your investments kill and destroy on top of part of the scientific method that requires me to check and document the new Dark Ages fueled by the Maue-seas. Thus, the LABI Limbaugh method of work avoidance predicts nothing but another free lunch for you – “Once more, I ask, Greg, why do you allow false and malicious posts on your site by Rhodes? … Posted by: Les Johnson | May 26, 2011 8:02 PM”.

    Much like going to a Morano-Massingill site, it is your toy-boy Maue types who claim all tropical cyclone activity in ACE and then not bother to include those in the South Indian and South Atlantic Oceans which would prevent PayPal appreciation for claims of the lowest ACE activity in 1,000 years. Fundsuckers, Florida State University’s Dr. Ryan Maue and Dr. Landsea are paid with public money yet never show how to calculate ACE which only magically produce Koch-Esso approved graphs to blend in with other extremist websites. Maue clearly spends more time on his beauty parlor head-shots than science unless he photo-shops in a few holes to be fair and balanced.

  39. #40 Robert Rhodes
    May 27, 2011

    Dearest Les, you are spending all your time in the corporate cover-up than actually doing any work (home, moral, science, and pseudoscience). For the rest, Y’all be sure to make pdf’s of Ly’n Ryan-types stab at ACE-whole science ‘cause he likes to patch things to fit the direction of the free AGW wind.

    For example, as of 5/27/11, Ly’n Ryan listed only 3 (01S One, 02S Anggrek, and 03S Abele) out of 12 tropical cyclones for “calendar-year 2010” from the South Indian Ocean in “Southern Hemisphere (2010-2011 Season)” (coaps.fsu.edu/~maue/tropical/index.html). Lazy and/or environmental racism, he didn’t bother to include or define the “season”: Cyclone-4 EDZANI, Tropical Storm MAGDA, Tropical Storm ELEVEN, Tropical Storm FAMI, Cyclone-4 GELANE, Tropical Storm HUBERT, Cyclone-1 IMANI, Tropical Storm ROBYN, and Tropical Storm SEAN (weather.unisys.com/hurricane/s_indian/2010/index.html).

    Only 1 of 11 in the South Pacific, 04P Tasha, was given as the only tropical cyclone for “calendar-year 2010” in “Southern Hemisphere (2010-2011 Season)” (coaps.fsu.edu/~maue/tropical/index.html). Lazy and/or environmental racism, he didn’t bother to include or define the “season”: Tropical Storm OLGA, Tropical Storm NISHA, Cyclone-4 OLI, Cyclone-2 PAT, Cyclone-3 RENE, Tropical Storm SEVENTEEN, Tropical Storm SARAH, Cyclone-4 TOMAS, Cyclone-5 ULUI, and Tropical Storm PAUL (weather.unisys.com/hurricane/s_pacific/2010/index.html)

    Extremist Tropical Cyclone expert Maue lists 2011’s Tropical Storm VINCE as from the South Pacific when it is from the Indian Ocean. Tropical Cyclone 06S (Vince) – The convection on or about 1/11/11 near 14.9S 107.8E, in the Learmonth, Australia region developed into a hurricane ecosystem from prediction week 1/2 – 8/11 (usno.navy.mil/JTWC).

    Extremist Tropical Cyclone expert Maue doesn’t list anything in the South Atlantic for 2010 and 2011 whereas there were 2.

    “NASA’s Aqua satellite spotted some strong convection in a recently formed low pressure area that strengthened into Sub-Tropical Storm Arani in the South Atlantic. … near the coast of Brazil” (“NASA’s Aqua Satellite spots rare Southern Atlantic sub-tropical storm”; Contact: Rob Gutro, NASA/Goddard Space Flight Center; eurekalert.org, 3/15/11).

    “Tropical Storm 90Q is the second known tropical cyclone to form in the cooler South Atlantic Ocean, and two NASA satellites confirm it is now moving away from Brazil’s coast. … located about 325 miles east of Puerto Alegre, Brazil in the waters of the South Atlantic Ocean near 30.0 South latitude and 45.8 West longitude … NASA’s Aqua satellite captured an infrared image of 90Q. … some high, cold thunderstorms in the center of the storm, confirming strong convection in the storm. … One agency in Brazil also issued warnings on the storm calling it “1-T Alfa” (“Second only south Atlantic tropical storm: 90Q, moving away from Brazil”; Contact: Rob Gutro; NASA/Goddard Space Flight Center; eurekalert.org, 3/11/10).

  40. #41 Les Johnson
    May 27, 2011

    Stephanie: your

    I can see your confusion, Les, but the comment about winter refers to your 1998 to the present statistics.

    The confusion is on your part, Steph. I stated the intervals 1930-1980, in reference to Greg’s assertion that warming may have caused the 1970s tornadoes. I also continued to define the period at each post.

    Also, it shows that you still have not looked at the data. The period 1998 to present has a cooling spring period, also a cooling YTD, also a cooling feb-mar-apr.

    In fact, all seasons except summer show a negative trend 1998-present. And summer is flat, at +0.1 deg F per century.

    But nothing you’re saying tells me why you want to start a temperature chart in 1930 to compare to a tornado chart that starts in the 50s or why you would look at year-round average temperature to talk about a spring-summer phenomenon.

    If you had looked at the data, you would have seen that 1930-1970 had a cooling spring. If that period was cooling, then warming was not likely the cause of the tornadoes in the 70s.

    The reason for 1930? Climate is generally considered on 30 year or more scales. I went back 50 years.


    Or why you would think national average temperature is so terribly important when we’re talking about temperature differences between clashing air masses.

    Because the colliding air masses were over the nation of the US.

    But, fair enough point. If you look at state temperature records, Missouri has had a relatively flat 1 deg/century rise over the last 100 years. Over the last 20 years, the temperature has a negative 4 deg F per century cooling.

    http://climvis.ncdc.noaa.gov/cgi-bin/cag3/hr-display3.pl

    If you don’t like my start dates, then look at the latter years vs the long term average. The last 5 years have the Feb-Mar-Apr period at or near the long term average.

    The numbers for OK are similar.

  41. #42 Greg laden
    May 27, 2011

    Les … Cooling in the spring correlated with increased toe ASIC activity corresponds with the model.

  42. #43 Les Johnson
    May 27, 2011

    Greg: your

    Les, are you specifically suggesting that Rhodes not be allowed to comment here?

    Yes, I am. He is attacking two highly respected scientists, with false and malicious statements.


    Otherwise, if you have a problem with what he’s said, go right ahead and duke it out!

    I tend to avoid paranoid, rambling and irrational people. Its a personal quirk.


    First of all, drop this “as a scientist” shit. That’s a load of crap. Drop it now or you’re gone.

    If you don’t want me to refer to you as a scientist, I shall comply.

    Regarding empirical vs. models: Are you claiming that the tornado data are reliable and posess century long homoscedasticity?

    It would be difficult to assign homogeneity of variance to a chaotic function. However, researchers in the field suggest that severe storms are better tracked than the total number. In the past, smaller, shorter duration storms were more likely to be missed. Larger , more severe are less likely. This applies to tornadoes and hurricanes.


    In any event, AS A SCIENTIST I would not base much on sucky data. Models, on the other hand, can be rather useful. I’m not sure why, AS A SCIENTIST you would think otherwise.

    Models are only useful as long as they match the data. As someone said (I forget who), models should be used, but not believed. If one of my engineers came to me and said he was believing the model, is spite of conflicting data, then he would likely be unemployed.

    I’ve been assuming that you are the Les Johnson at NASA, have I got that wrong? (Or am I thinking of someone else).

    No, I am not that LJ.

    But again, I’m not trying to make the case that AGW has increased tornadoes.

    Its implicit in your question, though.

    However, my gut feeling is that storminess in general is increased by AGW,

    And explicit in this statement.

    a situation where models may be the best way to go. For reasons I’ve stated several times.

    I believe data. Also, as I have shown, models can also predict a lessening of storm severity. If we have two different models, with two different results, I’ll take the data.

  43. #44 Les Johnson
    May 27, 2011

    Greg: your

    Les … Cooling in the spring correlated with increased toe ASIC activity corresponds with the model.

    Of course it does. Tornado activity needs warm moist southern air, meeting cold dry northern air.

    Most AGW theory, however, predicts an increase in activity with warming annual temperatures. Steph was unhappy with annual temperatures, so I showed her that spring temps 1930-1980 had also declined. And fall and winter and summer.

  44. #45 Greg Laden
    May 27, 2011

    “First of all, drop this “as a scientist” shit. That’s a load of crap. Drop it now or you’re gone.

    If you don’t want me to refer to you as a scientist, I shall comply.”

    Les, you did not understand what I meant. You seem to be in the business of telling me how to act and what to say in order to meet your personal criteria of acceptability. I’m telling you that this is not appreciated. Is there a way I can be more clear?

    I tend to avoid paranoid, rambling and irrational people. Its a personal quirk.

    The guy may indeed be a bit of a nut bag. I have no clue what he is saying. But again, I’m not sure what qualified you to tell me what to do here. You’re telling me what I need to think and say to be a scientist, you’re telling me how to run my blog. In both instances you are wasting your time and irritating me.

    It would be difficult to assign homogeneity of variance to a chaotic function.

    You missed the point. Willfully, I suspect. I’m not talking about a change in variance of the phenomenon. I’m talking about a change in variance of the data set. Are you saying there isn’t one? Interesting.

    Models are only useful as long as they match the data. As someone said (I forget who), models should be used, but not believed. If one of my engineers came to me and said he was believing the model, is spite of conflicting data, then he would likely be unemployed.

    All true but again you are missing the point. My point is that when sucky data conflict with a reasonable model, you don’t go with the data. You may or may not go with the model. I chose in this case to like the model provisionally.

    Regarding your point 44: Now you’re playing a game of sophistry. I see that argument as settled.

  45. #46 Les Johnson
    May 27, 2011

    Greg: on Rhodes… shrug…its your house.

    your

    Are you saying there isn’t one? Interesting.

    No, I said that the signal is clearer in the severe storm numbers. With data to back it.

    I chose in this case to like the model provisionally.

    Why this model? Why not von Storch’s model, which shows a decline in severe weather in a warming world?

    Regarding your point 44: Now you’re playing a game of sophistry. I see that argument as settled.

    Never an argument. Tornadoes need cold air to form. In fact, looking at the thread of my arguments, you can see that its at least implied, that tornado formation is favored in a cooling climate. Whether this decline is permanent or as a cycle as part of a larger increase is immaterial.

    Again, I changed the parameters from annual to spring, to show that Steph was wrong on all counts. As well, you had implied that warming was responsible for the tornadoes in the 70s. The data shows this to be probably incorrect, whether annual or spring temperatures are used.

  46. #47 Greg Laden
    May 27, 2011

    that tornado formation is favored in a cooling climate.

    We are currently having more tornadoes than ever (this year) in a very warm year. So your model only works sometimes?

    As well, you had implied that warming was responsible for the tornadoes in the 70s.

    You are always going to win your argument if you make up what whose with whom you are arguing said.

  47. #48 Stephanie Z
    May 27, 2011

    Greg, you mean like making up which period I was talking about even after he’s been corrected? What do really expect of anyone who pulls that “Steph” crap while arguing with me?

  48. #49 Greg Laden
    May 27, 2011

    At least it hasn’t reached “Stephie” level. Or worse, “Stefi”

  49. #50 Les Johnson
    May 27, 2011

    Greg: your

    We are currently having more tornadoes than ever (this year) in a very warm year. So your model only works sometimes?

    Warm? Not in the US. The 3 month period Feb-Mar-Apr is the 67th warmest year since 1895. Or, the 49th coldest. In other words, pretty average, but slightly cool.

    http://climvis.ncdc.noaa.gov/cgi-bin/cag3/hr-display3.pl

    your

    You are always going to win your argument if you make up what whose with whom you are arguing said.

    I am not making anything up. This is what you said, from Post 16:

    Having a lot of tornadoes in the 70s does not mean that global warming is not a factor. The 70s is well within the era of increased carbon in the atmosphere.

    My emphasis.

    The 70s were, for the most part, lower than the 1901-2000 average, and temperature had a negative trend for 50 years to that point. Its unlikely warming had anything to do with the outbreaks in the 70s.

  50. #51 Les Johnson
    May 27, 2011

    Stephanie: My apologies for using the familiar.

    your

    Greg, you mean like making up which period I was talking about even after he’s been corrected?

    Except, I had always specified which dates I was talking about. You didn’t. When you finally did specify 1998 to present, I showed you to be wrong there, too. All seasons except summer show a negative trend 1998-present. And summer is flat.

  51. #52 phillydoug
    May 27, 2011

    http://www.ijc.org/rel/pdf/climate_change_2003_part3.pdf

    “The global mean temperature has increased 0.6 ± 0.2 oC over the 20th century. Analysis of the instrumental record since 1861 suggests that the warmest decade globally may have been the 1990s and 1998 may have been the warmest year (IPCC, 2001: 26). Paleoclimate data for the Northern Hemisphere corroborates this; it also indicates that the temperature increase of the 20th century was the largest during the past 1000 years.

    Mean annual temperatures for Canada and the United States have increased (see Figures 2-1 and 2-2). The increase from 1900 to 1998 was 0.9oC for southern Canada while in the contiguous United States it was 0.4oC from 1900 to 1994 (Zhang et al., 2000, 405; Karl et al., 1996: 282). Regional differences in the patterns of warming for Canada and United States are illustrated in Figures 2-3 and 2-4.

    Winter and spring in Canada have exhibited the greatest warming, while summer has less warming; in autumn some areas actually experienced a small cooling (Zhang et al., 2000). Most of the warming in the United States has also occurred in winter and spring (Karl et al., 1996). Within the Great Lakes region, annual mean temperatures have increased by 0.7oC from 1895 to 1999 for the southern portion of the Great Lakes and St. Lawrence lowlands in Canada, (Mortsch et al., 2000: 159). Paleoclimate reconstructions over the last 12,000 years for the Great Lakes region indicate that temperatures have been up to 7°C cooler and 3°C warmer in the past (Magnuson et al., 1997: 829).” (pp. 4-5)

    “In a U.S. study of the correlation between temperature change and precipitation, Zhao and Khalil (1993) reported that, in a region to the south of the Great Lakes, when winter temperature increased precipitation also increased. Conversely, this region showed a decrease in precipitation with increasing temperature in May, June, July (not significant); a similar strong relationship (significant) occurred in the Central Great Plains agricultural area.” (pg. 11)

    “In the United States, extreme events have made up a disproportionate share of the observed increases in total annual precipitation. For example, the number of days with precipitation greater than 50.8 millimetres (two inches) has increased (Karl et al., 1996). Easterling et al. (2000) reported an increase in the frequency of one-day to seven-day precipitation accumulations exceeding one-year and five-year return periods. These increases are largest in the Great Lakes, and southwest and midwest regions of the United States.” (pg.12)

    “Extreme precipitation is expected to increase in a warmer world; this is consistent with a warmer atmosphere having a greater moisture-holding capacity (Trenberth, 1999; Kharin and Zwiers, 2000). Moderate and heavy precipitation depends primarily upon the moisture already in the atmosphere with advection and re-supply of moisture by storm circulation also playing a role (Trenberth, 1999).

    Analyses of precipitation extremes in GCMs and RCMs indicate more heavy precipitation events, fewer moderate events and more dry days or days with light precipitation (Cubasch et al., 1995; Hennessy et al., 1997; Jones et al., 1997 in Trenberth, 1999; Trenberth, 1999). ” (pg. 38)

  52. #53 Les Johnson
    May 27, 2011

    I have 106 listings in my database on “Storm Intensity”. These are some…

    http://www.nssl.noaa.gov/users/brooks/public_html/damage/tdam1.html

    http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=910&tstamp=200802

    http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-spm.pdf

    http://www.aoml.noaa.gov/hrd/tcfaq/E11.html

    http://www.sciencedirect.com/science/article/B6VFV-51H009Y-1/2/80b427fe8ed1a77cfed562862fcc94db

    http://rogerpielkejr.blogspot.com/2010/11/why-there-are-no-trends-in-normalized.html

    http://www.aoml.noaa.gov/hrd/hurdat/ushurrlist18512009.txt

    http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch11s11-1-3.html

    http://www.nytimes.com/cwire/2011/01/04/04climatewire-finding-the-fingerprints-of-climate-change-i-22773.html

    http://www.gfdl.noaa.gov/21st-century-projections-of-intense-hurricanes

    http://www.wrh.noaa.gov/sgx/document/weatherhistory.pdf

    http://www.redlandsfortnightly.org/papers/Taylor06.htm

    http://www.climatechange.qld.gov.au/pdf/climateqreport/climateqreport-chapter4.pdf

    http://www.co2science.org/articles/V14/N3/C1.php

    Zahn, M., and H. von Storch. 2010. Decreased frequency of North Atlantic polar lows associated with future climate warming. Nature, 467, doi:10.1038/nature09388.

    http://www.thegwpf.org/the-observatory/1378-indur-m-goklany-global-death-toll-from-extreme-weather-events-declining.html

    http://onlinelibrary.wiley.com/doi/10.1002/joc.2044/abstract

    http://www.theaustralian.com.au/news/nation/operator-of-dam-
    invented-rain-data/story-e6frg6nf-1226028379093

    http://www.amos.org.au/news/id/111

    http://www.theaustralian.com.au/national-affairs/climate/climate-change-to-mean-fewer-cyclones-and-smaller-waves-says-csiro-research/story-e6frg6xf-1226033322365

    http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V6R-51FXRG0-2&_user=10&_coverDate=01%2F01%2F2011&_rdoc=1&_fmt=high&_orig=gateway&_origin=gateway&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=427bc76ca877b9878fe0e8b454224b64&searchtype=a

    http://www.agu.org/pubs/crossref/2011/2010JD015493.shtml

    http://www.agu.org/pubs/crossref/2011/2010JD015493.shtml

  53. #54 Robert Rhodes
    May 27, 2011

    Dearest Les,

    “Les, are you specifically suggesting that Rhodes not be allowed to comment here? … Yes, I am. He is attacking two highly respected scientists, with false and malicious statements. … Posted by: Les Johnson | May 27, 2011 7:47 AM”.

    In reality, making up numbers (before, during, and after) and using exceedingly poor data sets or selected (cherry picking) is only telling the truth concerning people who get paid to be extremist Republican and Christian hurricane ecosystem experts that turn into experts of all events (almost like geologists) when the t-GOP is in power. FSU Fed grant sucker Maue powee was already debunked but currently enjoys life as the un-dead with 5-Watts’ corporate hoe seminar of the “world’s most viewed climate website” and “VOTED BEST SCIENCE BLOG”.

    Limited ACE-hulls for Landsea’s Atlantic only and not bothering with the rest of the world, “A). … 4). ACE-hole gate (hurricanes) is the lies, fraud, and malfeasance of publicly funded research by extremist Republican and Christian approved “scientists”, Florida State University’s Dr. Ryan Maue and NOAA’s Dr. Chris Landsea based on generating Accumulated Cyclone Energy (ACE) for 2010 to profit from ignoring real science, real numbers, and real global warming catastrophes. … By accident, NOAA’s Landsea provided some raw data in scientifically useful form. Yearly Accumulated Cyclone Energy could not be found under noaa.gov’s search engine. But “en.wikipedia.org/wiki/Accumulated_cyclone_energy” provided
    “File:Atlantic ace timeseries 1850-2007.jpg” with the link “aoml.noaa.gov/hrd/tcfaq/E11.html”. Also failing to use spellcheck on the name of their main science-like tool, “The Atlantic hurricane database (or HURDAT) extends back to 1851. … “ACE” = Accumilated Cyclone Energy – An index that combines the numbers of systems, how long they existed and how intense they became. It is calculated by squaring the maximum sustained surface wind in the system every six hours and summing it up for the season … References: Landsea, C.W. … C. W. Landsea” (“Frequently Asked Questions”; “Subject: E11) How many tropical cyclones have there been each year in the Atlantic basin? What years were the greatest and fewest seen?”; Contributed by Chris Landsea; Hurricane Research Division; aoml.noaa.gov/hrd/tcfaq/E11.html, 5/28/10)” (“GBRWE 10/24 – 30/10”s Extreme Planetary Warnings for Earthquakes, Volcanoes, and Solar/Terrestrial Flares from Human Activities”; Robert Rhodes, Supplemental; GBRWE 10/24 – 30/10, 10/23/10).

  54. #55 Greg Laden
    May 27, 2011

    Les, you can argue all you want that i said or meant something other than I said or meant, but it won’t get you very far. I made only one point about the 1970s: That you were using the 1970s as though they were pre-global warming, but this assumes global warming to be a very recent phenomenon. I’m sorry if you misunderstood that.

  55. #56 Stephanie Z
    May 27, 2011

    Les, you may have a little problem with getting so wrapped up in arguments, you can’t actually see what was discussed. Oops, I used “tornado season” for “summer,” because that’s the best fit for where I live. But rather than deal with the actual criticism, which is that this information is crap (not granular enough to be useful and highly responsive to fiddling based on date range), you decide to keep saying I didn’t look at the data.

    Why would anyone listen to you, much less talk to you long enough to find out what the fuck you think you’re arguing against?

  56. #57 Brook
    May 27, 2011

    Les your first link says nothing about intensity, and your second link supports Dr. Laden’s original post. (I suspect he has seen it.)

  57. #58 Les Johnson
    May 28, 2011

    Brook: your

    Les your first link says nothing about intensity, and your second link supports Dr. Laden’s original post. (I suspect he has seen it.)

    The first link is to normalized damage from major tornadoes. I am not sure why you say this not related to “storm intensity”.

    The second reference, if you scroll down, shows that major tornadoes have declined on a decade to decade basis. (on a pro-AGW site, BTW)

    As we have discussed, tornado reporting has improved, hence the total number of tornadoes has increased (the first chart on Weather Underground). But this is probably not an indication of the actual trend. Major storms are probably a better indicator (the second chart).

    It should be noted that some of my references also support Greg’s point of view. I have no problem looking at data from both sides of the debate.

  58. #59 Les Johnson
    May 28, 2011

    Greg: your

    I made only one point about the 1970s: That you were using the 1970s as though they were pre-global warming, but this assumes global warming to be a very recent phenomenon.

    I never stated that the 70s were pre-warming. That would be a nonsensical statement, in light of my other statements regarding a long term warming trend of 100+ years.

    My point though, is that there was demonstrably no warming in the 70s. It was at the end of a long decline, and the temperature anomalies were below the long term average. The fact that this occurred inside a longer term warming trend is irrelevant. It was a temporary cooling period in a long term warming trend.

  59. #60 Les Johnson
    May 28, 2011

    Stephanie: your

    Les, you may have a little problem with getting so wrapped up in arguments, you can’t actually see what was discussed. Oops, I used “tornado season” for “summer,” because that’s the best fit for where I live. But rather than deal with the actual criticism, which is that this information is crap (not granular enough to be useful and highly responsive to fiddling based on date range), you decide to keep saying I didn’t look at the data.

    You didn’t look at the data. You said that only the winter temperatures have seen a decline 1998-present. That is false. All seasons except the summer show a decline. And the summer is flat. This is irrefutable using the data at NOAA.

  60. #61 phillydoug
    May 28, 2011

    Brook: “Les your first link says nothing about intensity, and your second link supports Dr. Laden’s original post. (I suspect he has seen it.)”

    Much thanks, Brook; I thought I was being a glutton for punishment clicking on all the links Les threw against the wall. (I might still be glutton for punishment, but not the only one.)

    Les,

    Not sure which of the links you posted addressed the specific data I referred to.

    Here was your claim (@51): “All seasons except summer show a negative trend 1998-present. And summer is flat.”

    This is a claim about mean temperatures. I cited data that showed the patterns of increasing temperature, and increasing frequency of intense precipitation events, and the correlation between the two. Which of these do you disagree with? Point to specific research that shows different temperature and precipitation observations; this would help if there is to be a conversation.

    If you don’t contest the data I excerpted, then please explain what your claim is intended to establish. Are temperatures not going up, and not related to increasingly intense and frequent precipitation events (storms)?

    I found the link to an economic analysis of tornado damage especially perplexing (I assumed you intended to show that increased damages in dollar value is simply about increased development in storm prone areas, not more destructive and frequent storms); see, Greg’s original post was about whether there is now evidence that AGW is contributing to more frequent and intense storms– I thought he was awfully reserved in saying: “The question at hand is this: Are the bad years getting worse, and are the not-so-bad years getting bad, or are the bad periods getting more common? To address these questions empirically it will be necessary to have at least a few decades worth of good data under conditions of global warming. We probably have those data now, or almost so. This question will be settled by reasonable people reasonably soon.”

    Hey, it’s his blog, he can be all careful and reasonable if he wants. I don’t have his patience.

    Do you have data that supports your claim– directly– and contradicts the data I provided– directly– or not?

    Or is this a competition to determine whose link chain is longer? If that’s all this is, knock yourself out. You da’ man. All bow before you’re massive link directory. Heck, if I weren’t married, I might try it as a pick up line at the next conference I go to– “You should see how big my link directory is…”

  61. #62 Greg Laden
    May 28, 2011

    The fact that this occurred inside a longer term warming trend is irrelevant.

    Oh, I see … you are assuming that there will be a perfect interannual correspondence between one simple factor and one complicated outcome. How quaint!

    I don’t think so, though.

  62. #63 Les Johnson
    May 28, 2011

    Greg: your

    Oh, I see … you are assuming that there will be a perfect interannual correspondence between one simple factor and one complicated outcome. How quaint!

    I don’t think so, though.

    No, I never said nor implied that. However, stating that one simple factor (warming) may cause increased tornadic activity is an example of what you accuse me of. The fact that there was no warming in the 70s however, should prove against this assumption.

  63. #64 Les Johnson
    May 28, 2011

    phillydoug: your

    I found the link to an economic analysis of tornado damage especially perplexing

    It shouldn’t be. The authors at NOAA state that there is no trend in normalized damage from major tornadoes. That means no increase in major storms, using the metrics described.

    They also reference Pielke Jr, who had the same findings in other natural disasters (floods, hurricanes).

  64. #65 Les Johnson
    May 28, 2011

    phillydoug: your

    Do you have data that supports your claim– directly– and contradicts the data I provided– directly– or not?

    Yes. I linked to the NOAA temperature database, which shows that there was little or no warming in the areas described, over the periods outlined.

    You do realize that most of your references use models, and not empirical data, right?

  65. #66 Greg Laden
    May 28, 2011

    Les [63] I think you need to think this through more carefully. The 1970s are not exempt from prior warming. There had been warming. It is a post-warming decade. Or are you saying that it is the rate, not the state, of climate change that matters?

  66. #67 Les Johnson
    May 28, 2011

    Greg: your

    Les [63] I think you need to think this through more carefully. The 1970s are not exempt from prior warming. There had been warming. It is a post-warming decade. Or are you saying that it is the rate, not the state, of climate change that matters?

    Actually, the 70s would be exempt from prior warming. The fact that the years in question were mostly at or below the long term average, however, would suggest that warming was NOT the cause of the tornadoes in the 70s. Prior warming might have some temporal connection, but I doubt it. I am not aware of anyone even suggesting this possibility.

    It might be rate, state , or both. Or none of the above.

  67. #68 Greg Laden
    May 28, 2011

    Les, once again and for the last time, anthropogenic global warming is a process that has been going on for a very long time. The 1970s were not cooler than the pre-global warming average or even the early global warming average. If you cherry pick the data I’m sure you’ll find that somewhere this is true, but not globally.

  68. #69 Les Johnson
    May 28, 2011

    Greg: No, according to NOAA data, the US was below the long term average for 6 of the 11 years 1970-1980. For spring data (Mar-Apr-May), the temperature was at or below normal for 8 of the 11 years.

    http://climvis.ncdc.noaa.gov/cgi-bin/cag3/hr-display3.pl

    I can look up HADCRUT or GISS global data, but they will tell the same story. The 70s were a temporary cooling of a long term warming trend. Granted Anthro warming has occurred for as long as 10,000 years, but not in the 70s. Any anthro warming was overwhelmed by natural negative forcings, and possibly Anthro aerosols.It was cooling, not warming.

    Unless there was a temporal connection to earlier warming,
    warming cannot be blamed for the 70s tornadoes.

    I would be happy to look at any temperature record you have that states otherwise. You have a source?

  69. #70 Greg Laden
    May 28, 2011

    Les, at the moment your link is borked. meanwhile ….

    Ie this

    The “long term average” is not an appropriate baseline to reprsent pre-global warming levels. It is an arbitrary line used for convenience. The 1970s was warmer than, for example, all modern decades prior to WWII (i.e, the 19th century and first half of the 20th century)

    Les, either you are simply not getting this stuff or you are an unabashed cherry picker.

  70. #71 Andy
    May 30, 2011

    Hello everyone !

    I just wanted to address the fact that no one here seems to have heard of global cooling caused by reflexion of solar radiation by floating aerosol and dust particles. That’s very surprising to me because I’m not a scientist myself, I’m a banking auditor. But I read a french publication by monthly called Science and Life and they recently ran a very good article about global cooling.

    In short:

    1. Up until now the net effect of human activity has been to cool the earth by blocking radiation from the sun from reaching the surface

    2. With the end of the industrial revolution era and the reduction in use of certain technologies (i.e. less coal) the net effect inverted towards the end of the 20th century and turned to global warming

    That could explain the data you’re all looking at no ? Also, while I am 110% convinced of the reality of climate change, I have to agree with Les Johnson, if the data says something different that the model, the model is wrong, not the data.

  71. #72 Greg Laden
    May 30, 2011

    Andy, we’ve all heard of aerosols, and Les’s constant reference to “the 70s” and other bumps in the record is an indirect reference to the effects of aerosols on climate.

    You are both wrong when you insist that when the model and data are different, the model is wrong. That sounds great, because of the way you may have learned about the scientific method and such in school, but that is not how it works.

    I’ve not mentioned this prior in this discussion, but you need to realize that “models” are not hypotheses or theories. They are more fluid and complex than that. Models, in climate studies, are very much based on data. They aren’t just formulas that reflect an idealized norm expressed as predicted results. They are a combinations of empirically derived multivariate regression models, factor analyses, or some other empirically based constructs, that are used to predict things. The degree to which a model is theorized vs. a simply extension of empirical data varies.

    Meanwhile, the data varies a lot in its quality. If you have a pile of crappy data saying one thing and a well tuned and highly developed model saying another thing, you’d be kinda dumb to go with the data over the model because of some fetishized misunderstanding of how inference in science works.

    Now, Andy, bot the aerosol gambit and the model/empirical gambit, and a budding aliance with AGW Denilaist Les, has got you on probation here. A nasty cold, a daycare system breakdown, and a leaking hot water heater distracted me enough to let Les go for a while before shutting him down. Don’t imagine that you somehow deserve the same degree of leeway. He didn’t, you don’t.

    I remind everyone again that with respect to AGW and denialism, this blog has a policy.

  72. #73 Lurker
    June 8, 2011

    Greg Laden,

    Re: Les Johnson

    Hahahahahaha!

    Les Johnson has a history of stalking the Internet trying to impress himself with his “scientific prowess”.

    When he crows “ps- I work in modeling fluids and fluid flows” he fails to mention that his modelling is done under the auspices of the petroleum industry. Surprised?

    Kudos to Stephanie Z for making the “Laugh at Les Show” so entertaining and to you of course for your patience.

  73. #74 george
    June 13, 2011

    I love the roundy roundy arguments based on a paucity of solid data that can barely be analyzed even with advanced statistics.

    Greg, I believe you have mistaken models for statistics. Even the folks at Real Climate admit that climate models are hypotheses. A model is a mathematical construct that attempts mimic the reality underlying a dataset…. some radiation absorption, some re-radiation, some reflection, some atmospheric mixing, a bit of feedback…..From statistics 101- fitted curves are never valid for predicting outside the dataset. You might be able to fit a polynomial or an exponential to a data set, but unless you know what the underlying mechanism is there is no guarantee either will make a useful or valid prediction.

    Just one question about tornadoes? I’m looking for a good place to build a retirement house. If I don’t want to get hit by a tornado which is a better choice- southern Oregon, southern Missouri or Wales? and why? The southcentral US isn’t nicknbamed Tornado Alley on a whim.

  74. #75 Greg laden
    June 13, 2011

    George, thanks for the advice on stats and models and stuff. I coulda used your help last time I taught the topic … Course, I’ve only done that at the grad level so far so what do I know.

    Does it matter that nothing you’ve said relates to anything in this post? Prolly not …

  75. #76 Rocky H
    June 13, 2011

    There is no measurable, testable evidence, per the scientific method, showing any global harm from CO2. None. And there is plenty of empirical (real world) evidence showing that more CO2 substantially increases agricultural productivity.

    Conclusion: CO2 is both harmless and beneficial. More is better.

    Thus, the demonization of “carbon” by catastrophic AGW true believers is deconstructed by using verifiable facts, and easy to understand logic.

    Sorry about your scary conjecture. It’s dead, Jim.

  76. #77 Greg Laden
    June 13, 2011

    Rocky, increased CO2 in the atmosphere increases the productivity of some plants a certain amount, then after that no increase is achieved. Conclusion, more is not beneficial. The link between CO2 and global warming is firmly established by real science. Conclusion: More is harmful.

    You violated blog commenting policy by having a link to an AGW denialist site. In order for me to post your comment I had to change the link to point somewhere else. I hope you don’t mind.

  77. #78 Gloria
    June 13, 2011

    Hahahahah Rockey, you play a great banjo!

  78. #79 Rocky H
    June 14, 2011

    I don’t mind your blog’s censorship, Greg. It’s the only way [DELETED]

    And for your information, there is [DELETED]

    If you believe there is evidence, per the scientific method, showing [DELETED]

    There is no [DELETED] Therefore, CO2 is [DELETED]

    Conclusion: [DELETED]

    The [DELETED]

    The previous post violated blog posting policy in several locations, but rather than deleting the entire post I thought people would like to see the gore. This is what happens when everything that is made up alarmist rhetoric is removed from an AGW denialist blog comment.

  79. #80 Jeremy
    June 15, 2011

    I think it’s important to note that cooling trend from 1998 is a local phenomenon, but not a global phenomenon, where there happens to be a cooling trend from 1998 to 2005 in one set of data, but it becomes a warming trend in all data looking at 1998 to 2007 or later. 1998 is chosen of course, because it was an outlier hot year. I note that with the US data that Les is using, while you still get local cooling trends, if you choose 1997 or 1999 as your starting year, you get much less severe cooling trends, and if you use a much wider data set, of course yet get an increase instead of a decrease.

    I think what’s most telling about extreme whether in the US is this;

    http://2.bp.blogspot.com/-yPpkRZg_Wdg/TfKGl13-RwI/AAAAAAAACOI/S3b047Gg1AM/s1600/temp.records.060911.jpg

  80. #81 Jeremy
    June 15, 2011

    My last picture is a histogram of monthly total number of daily high temperature and low temperature records set in the U.S. for June 2010 through June 9, 2011, data from NOAA.

  81. #82 Oliver Serum
    September 1, 2011

    How can cartoon penguins save us from global warming?

  82. #83 Soufiane
    dyCAGTvBJK
    July 22, 2012

    Tornadic shots most often are rain-wrapped and gray. This is extraordinary and tenrfiyirg to me, reminiscent as it is of the fires we’re facing.There is such a thing as a fire-nado , and the similarities in sound between an out-of-control wildfire and a tornado are remarkable. Your image draws the comparison between two forces of nature beautifully.