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Weather extremes: atmospheric waves and climate change

The northern hemisphere has experienced a spate of extreme weather in recent times. In 2012 there were destructive heat waves in the US and southern Europe, accompanied by floods in China. This followed…

People affected by floods move to higher grounds in Khoski, Sindh province, Pakistan, 17 September 2011. AAP

The northern hemisphere has experienced a spate of extreme weather in recent times. In 2012 there were destructive heat waves in the US and southern Europe, accompanied by floods in China. This followed a heat wave in the US in 2011 and one in Russia in 2010, coinciding with the unprecedented Pakistan flood – and the list doesn’t stop there.

Now we believe we have detected a common physical cause hidden behind all these individual events: each time one of these extremes struck, a strong wave train had developed in the atmosphere, circling the globe in mid-latitudes. These so-called planetary waves are well-known and a normal part of atmospheric flow. What is not normal is that the usually moving waves ground to a halt and were greatly amplified during the extreme events.

Looking into the physics behind this, we found it is due to a resonance phenomenon. Under special conditions, the atmosphere can start to resonate like a bell. The wind patterns form a regular wave train, with six, seven or eight peaks and troughs going once around the globe (see graph). This is what we propose in a study published this week together with our colleagues of the Potsdam Institute for Climate Impact Research (PIK).

Planetary waves

Normally, an important part of the global air motion in the mid-latitudes of the Earth takes the form of waves wandering around the planet, oscillating irregularly between the tropical and polar regions. So when they swing northward, these waves suck warm air from the tropics to Europe, Russia, or the US; and when they swing southward, they do the same thing with cold air from the Arctic. This is a well-known feature of our planet’s atmospheric circulation system.

However, during several recent extreme weather events these planetary waves almost froze in their tracks for weeks. So instead of bringing cool air after having brought warm air before, the heat just stays. And stays. And stays. In fact, we detected a strong amplification of the usually weak, slowly moving component of these waves.

Time is critical here: two or three days of 30°C are no problem, but 20 or more days lead to extreme heat stress. Since many ecosystems and cities are not adapted to this, prolonged hot periods can result in a high death toll, forest fires, and devastating harvest losses.

The northward wind speed (negative values, blue on the map, indicate southward flow) in the mid-latitudes of the northern hemisphere. During the extreme event (a record-breaking heat wave in the US), the normally weak and irregular waves were replaced by a strong and regular wave pattern. Vladimir Petoukhov

What does climate change have to to with it?

Climate change caused by greenhouse-gas emissions from fossil-fuel burning does not bring a uniform global warming. In the Arctic, the warming is amplified by the loss of snow and ice. This in turn reduces the temperature difference between the Arctic and, for example, Europe. Yet temperature differences are a main driver of air flow, thereby influencing the planetary waves. Additionally, continents generally warm and cool more readily than the oceans.

These two factors are crucial for the mechanism now detected. They result in a changing pattern of the mid-latitude air flow, so that for extended periods the slow waves get trapped. The irregular surface temperature patterns disturb the global air flow. This analysis is based on equations that our team of scientists developed, mathematically describing the wave motions in the extra-tropical atmosphere. The conclusions drawn from the equations were tested using standard daily weather data from the US National Centers for Environmental Prediction (NCEP).

During recent periods in which several major weather extremes occurred, the trapping and strong amplification of particular waves – like “wave seven” (which has seven troughs and crests spanning the globe) – was observed. The data show an increase in the occurrence of these specific atmospheric patterns.

This analysis helps to explain the increasing number of unprecedented weather extremes. It complements previous research that already showed that climate change strongly increases the number of heat records around the world, but which could not explain why previous records were broken by such stunning margins. The findings should significantly advance the understanding of weather extremes and their relation to man-made climate change.

The new data show that the emergence of extraordinary weather is not just a linear response to the mean warming trend, and the proposed mechanism could explain that.

Still, things are not at all simple. The suggested physical process increases the probability of weather extremes, but additional factors certainly play a role as well, including natural variability. Also, the 32-year period studied in the project provides a good indication of the mechanism involved, yet is too short for definitive conclusions.

So there’s no smoking gun on the table yet – but quite telling fingerprints all over the place.

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  1. Sherry Mayo
    Sherry Mayo is a Friend of The Conversation.

    logged in via Facebook

    How does this new work relate to Jennifer Francis' work on the weakening of the jet stream resulting in a more meandering jet stream path. Is this resonance a related phenomenon, something different/additional, or a more rigorous mathematical analysis of the same thing?

    [I am hoping for an answer from the authors]

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    1. David Arthur

      resistance gnome

      In reply to Sherry Mayo

      I'm not one of the authors, but I understand that weakening NH jet stream has been implicated in extreme NH events such as Atlantic Hurricane Sandy being blocked from a NE trajectory into the Atlantic by a blocking high and instead merging with a polar storm the the NW and being turned into Superstorm Sandy.

      My understanding is that this resonance is at least related to the weakening jet stream, and offers a mathematical description of the phenomenon.

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    2. takver takvera

      Journalist and Editor at Indymedia

      In reply to David Arthur

      There is a great 40 minute presentation by Jennifer Francis, from January this year, which I have embedded to the end of my article which discusses the Petoukhov & Rahmstorf paper. I have transcribed her opinion on the possible connection between atmospheric waves, sea ice and Hurricane Sandy. She says 'maybe' in regard to this connection.
      http://takvera.blogspot.com.au/2013/03/arctic-amplification-jet-stream-and.html

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  2. takver takvera

    Journalist and Editor at Indymedia

    Does this also apply to the southern hemisphere? and if so, to the same extent?
    We appear to be getting a blocking high in the Tasman Sea right now which may create a run of 9 days over 30 degrees C for Melbourne in March - a new record for any month if sea breezes don't bring down the temperature down.

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    1. Sherry Mayo
      Sherry Mayo is a Friend of The Conversation.

      logged in via Facebook

      In reply to takver takvera

      Probably not to nearly the same extent. the North pole has warmed far faster that the south due to its very different geography (a sea surrounded by land rather than the other way around), so the reduced temperature gradient between pole and equator that causes these blocking effects is much more noticeable in the northern hemisphere.

      Blocking highs in the Tasman have long been a feature of Australasian weather systems[1] but in the long run, the same reduced temperature gradient should occur in the southern hemisphere too which could make them a whole lot worse.

      [1] See page 200-202 of "The weather and climate of Australia and New Zealand", an undergrad text by by Sturman & Tapper

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    2. Dale Bloom

      Analyst

      In reply to Sherry Mayo

      By and large, the whole world has not had a significant increase in temperature in recent times, only the far north of the planet.

      There is certainly more land mass north of the equator than south, and more industry.

      “It is not implausible that the actual temperature increase with latitude in the Northern Hemisphere is reflecting the effect of the band of urban-industrial civilization between 25°N and 70°N.”

      http://www.sjsu.edu/faculty/watkins/polarwarming.htm

      A possibility for the difference in temperature above normal in the north could also be a change in ocean currents, or a change in the Artic Oscillation

      http://nsidc.org/cryosphere/arctic-meteorology/weather_climate_patterns.html

      Or, a combination of all three.

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    3. takver takvera

      Journalist and Editor at Indymedia

      In reply to Dale Bloom

      I can conjecture the different hemisphere land mass geographies cause more pronounced changes to atmospheric waves in the northern hemisphere and more extreme weather events. The Arctic is warming at double the average global rate.
      But substantial parts of Antarctica are also warming rapidly. The rate of warming on the Antarctic Peninsula was estimated at five times faster than the global mean rate. West Antarctica is warming at 3 times the global average. See Bromwich et al (2012), Central West…

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    1. In reply to Gerard Dean

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    8. In reply to John Nicol

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  4. Sean Lamb

    Science Denier

    Wake me up when you can make some successful predictions. Until then how do we distinguish this from post-facto just-so stories?

    We had a heatwave this summer in Australia, but it was quite brief. 40 years ago it would have just sparked a few headlines when it happened and everyone would have forgotten about it. But in this brave new world of climatic apocalyptic ideation it is instead studied with the same degree of concentration generally restricted to fair-ground fortune tellers for tea-leaves to see what portents of doom it holds for the future.

    We'll all be roined said Hanrahan....

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    1. David Arthur

      resistance gnome

      In reply to Sean Lamb

      Sean, nothing like this heatwave happened 40 years ago; have a read of the Related Articles to which links are helpfully located on the right hand side of this page.

      40 years ago, nothing like this heat wave COULD have happened because 40 years ago atmospheric CO2 was 50 ppm lower than present; that's the point.

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    2. Sean Lamb

      Science Denier

      In reply to David Arthur

      "nothing like this heatwave happened 40 years ago"
      Really?
      Well than 45 years ago or 63 years or 101 years ago - whatever the case may be.
      A heatwave by definition is just temperatures above the mean - by definition they happen all the time.

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    3. takver takvera

      Journalist and Editor at Indymedia

      In reply to Sean Lamb

      Sean, The January heatwave was significant for it's extent, duration, and number of temperature records broken. But perhaps you are not keeping up with the special statements of the Bureau of Meteorology, Climate Commission and CSIRO scientists, including on this site. It must feel good to have your head in the sand. Unfortunately denial isn't a very good method of risk management.

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    4. In reply to Gerard Dean

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    5. In reply to Dave McRae

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    6. In reply to Gerard Dean

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    7. In reply to Byron Smith

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    8. David Arthur

      resistance gnome

      In reply to Sean Lamb

      Thanks Sean.

      While it's true that human perception of heatwaves is relative, the ignition point of forests is not affected by how hot the tree feels that day.

      Another measurement might be the temperature at which human muscle protein denatures.

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    9. Sean Lamb

      Science Denier

      In reply to David Arthur

      It may well be that there is a positive feedback between large bushfires and the local temperature.
      What are the greatest risk factor for a bushfire breaking out? Other fires nearby? Lightening? Lack of rain recently? Quantity of fuel? Strong winds? Presence of arsonists or irresponsible human behavior? Or ambient temperature?
      We have had bush fires before near where I live. This was a fairly bad set, but we have had worse and more severe in decades gone past.

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    10. In reply to Gerard Dean

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    11. In reply to Byron Smith

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    13. John Nicol

      logged in via email @bigpond.com

      In reply to David Arthur

      David,

      There are records being broken every day with the words "the hottest in fifty years, the coldest in 120 years, the worst floods since 1878....". It is very likely that the recent heatwave is no different from others in the past before 1788, or even in say, the mid 1800s, when no one would have recorded the temperatures. After all, the highest floods in Brisbane's histroy were 1842 and 1883. The Darling River stopped running for three years in a row around 1856. These are known facts which do not get a lot of current publicity, It is very likely that other extreme events ocurred too long ago to have been recorded, so let's not get too carried away.

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    14. In reply to Byron Smith

      Comment removed by moderator.

    15. David Arthur

      resistance gnome

      In reply to Sean Lamb

      Thanks for your insights, Mr Lamb, however, I think you have succeeded in TOTALLY misunderstanding what I wrote.

      Ignition temperatures are functions of molecular properties, not of average ambient temperature. Therefore, if average ambient temperature changes, then the probability that a fluctuation from that average ambient temperature will equal or exceed that ignition temperature will change.

      On planet earth, average ambient temperatures are generally less than ignition temperatures. If…

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    16. In reply to Gerard Dean

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    17. In reply to Gerard Dean

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    18. David Arthur

      resistance gnome

      In reply to John Nicol

      Mr Nicol, maximum temperature records are being broken with increasing frequency, and minimum temperature records are being broken with decreasing frequency.

      That's a trend, in accordance with which we must expect events associated with and consequent upon extremely hot temperatures to become more frequent.

      My discussion with Sean Lamb in this thread might illuminate the subject for you.

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    19. Sean Lamb

      Science Denier

      In reply to David Arthur

      Ignition temperatures are indeed the function molecular properties - in this case 451 Fahrenheit.
      Human activity is the main cause of bush fires

      "The Bad News is, Country eventually becomes arid."
      Well the good news is if the country is really warming - although results may vary from locality to locality - we can expect more rainfall not less.

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    20. David Arthur

      resistance gnome

      In reply to Sean Lamb

      "Well the good news is if the country is really warming - although results may vary from locality to locality - we can expect more rainfall not less."

      Well the Bad News is, the country really is warming - and warming rates certainly do vary from locality to locality - even if we get more rainfall (much of Australia is getting less rainfall), we are also getting much more evaporation.

      Net result is less water availability at most locations most of the time.

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    21. John Nicol

      logged in via email @bigpond.com

      In reply to David Arthur

      David Arthur,

      I think if you consult tables on ignition temperatures and possible ambient temperatures on the earth, I believe you will find that, only where you have a particularly selected pair of substances will you go anywhere near spontaneous combustion in open regions. (Linseed oil and cotton does form a combustible combination if you heat it well above ambient temperature in the process of treating wooden structures) However, this is not a feature of trees in bush fires.

      The additional problem of bushfires on hot days is not that there will be more lit by lightening etc, but that the warm day produces more combustible gases from the trees and grasses once the fire is lit.

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    22. David Arthur

      resistance gnome

      In reply to John Nicol

      Thanks Mr Nicol, you are quite correct that I am using the term "ignition temperature" loosely, and I'm sure that the Black Saturday survivors will derive great comfort from your correction.

      Fact is, that day was just so hot the bush just caught fire far, far in advance of the fire front - and those sorts of conditions are going to be more and more frequent, particularly now that permafrost thawing has added an anthropogenically uncontrollable source of greenhouse gases emissions.

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    23. Peter Sommerville

      Scientist & Technologist

      In reply to takver takvera

      Really? Are you familiar with the methodology behind the BOM calculations? I think not. Do you have any understanding of the CSIRO claims. I think not. Such is the ignorance of the faithful that they no longer have the ability to critically evaluate the science being presented to them. You are a journalist - what are your skills to evaluate these reports?

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    24. Peter Ormonde
      Peter Ormonde is a Friend of The Conversation.

      Farmer

      In reply to Peter Sommerville

      But why Mr S ... why do all these boffins keep feeding us lies and hiding the truth from us? All of them.

      All these fibbing folks who have actually studied the stuff (beyond one undergraduate text book)... been published in the literature, won Nobel prizes and are considered by fools, governments and other scientists to be "experts".

      Sure they have the accolades, the huge truckloads of Moscow gold arriving in a constant stream the prestige and power - but have they no self-respect or decency…

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  5. David Arthur

    resistance gnome

    Thanks for this. The January heatwave in eastern Australia, and pronounced north-south trajectory of ex-TC Oswald and a subsequent sub-cyclonic weather system all seem to be consequences of a blocking near-stationary high pressure system over the Tasman Sea, as I commented on "What's Causing Australia's Heat Wave" (http://theconversation.edu.au/whats-causing-australias-heat-wave-11628).

    In Petoukhov et al's work, NH slowing jet stream is attributed to decreased temperature difference between low and high latitudes.
    1) Do such planetary waves occur in the Southern Hemisphere?

    2) Does their speed vary, and if so, why?
    I understand that there has been some warming around West Antarctica, but not so much around East Antarctica.
    Could changed auroral springtime conditions due to the ozone hole be a factor?

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    1. John Nicol

      logged in via email @bigpond.com

      In reply to David Arthur

      David, Your mentioning of the ozone hole which is another subject of controversy, reminded me of another very interesting phenomenon which has not has any attention as far as I am aware. A couple of years ago the IPCC published a world map showing the distribution of temperature increases and decreases in the form of a set of isotherms.

      The lines representing the largest increase were almost circular around the North Magnetic Pole. The lines showing the largest decrease, were similarly circular around the South Magnetic Pole. Yet no work appears to have been done to try to understand what processes involving cosmic rays which of course excite the aurora, might play in climate. The effect of the solar magnetic field on these rays is very well documented and many scientists suggest that these have a very significant effect on the formation of clouds, a very important controller of weather, and in the longer term, climate.
      John Nicol

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    2. David Arthur

      resistance gnome

      In reply to John Nicol

      Thanks for that information, Mr Nicol.

      Does the IPCC map factor in the rapid warming of Central West Antarctica? Observations are set out in Bromwich et al's "Central West Antarctica among the most rapidly warming regions on Earth", Nature Geoscience v6 (2) doi:10.1038/ngeo1671
      "The West Antarctic Ice Sheet is contributing to sea-level rise, but temperature trends in the region have remained uncertain. A complete temperature record for Byrd Station in central West Antarctica, spanning from 1958 to 2010, establishes West Antarctica as one of the fastest-warming regions globally."

      The various discussions in which you and I have previously participated are strong evidence that at one of us is impervious to any and all evidence of the primary influence of atmospheric greenhouse gases on earth's climate, to the extent of clutching at any and all straws.

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    3. Peter Ormonde
      Peter Ormonde is a Friend of The Conversation.

      Farmer

      In reply to John Nicol

      I'm wondering how lthose scientists tried and tried to convince folks like Mr Nichol here that the skin of the planet consisted of tectonic plates... or that rocks are actually a bit older than the Old Testament might give them credit for ... seems to have a certain reluctance to accept science over his "religious" faith-based conservatism. Just can't be true can it.

      As for those isotherms they'd be calibrated in the accursed Napoleonic decimals of centigrade wouldn't they - and we know that's…

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    4. Andrew Vincent

      Marketing . Communications . Multimedia

      In reply to John Nicol

      Research does continue in cosmic ray/cloud relationship. I believe there is are ongoing experiments at CERN.

      http://arstechnica.com/science/2013/02/hints-of-cosmic-ray-climate-link-in-sediment-core-from-japan/

      http://public.web.cern.ch/public/en/research/CLOUD-en.html

      But there are many issues with the theory of cosmic rays as a climate driver.

      The first is the mechanism - for cosmic rays to trigger cloud formation (currently being investigated).

      Secondly for clouds to give a clear…

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    5. John Nicol

      logged in via email @bigpond.com

      In reply to Peter Ormonde

      David Arthur and Peter Osmonde,

      May I say that it disappoints me in the extreme to find that a quite possibly relevant and engaging piece of scientific material can be treated with such disdain and apparent lack of thought. None of the comments in your responses appear to relate in any way to the information I was trying to make available to you. I had thought you were both people with whom one might be able to conduct an interesting exchange.

      By contrast, Andrew Vincent is a person who does…

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    6. Peter Ormonde
      Peter Ormonde is a Friend of The Conversation.

      Farmer

      In reply to John Nicol

      Mr Nickle,

      Yes it is appalling isn't it that this Osmonde bloke should think of you as an object of scorn and derision? That he should regard you as an unscientific clod unworthy of debate or discussion. At best a crank, at worst a poorly paid hack of the mining industry. Joh in a labcoat out in the shed second-guessing the world. It's quite insulting really isn't it?

      Osmonde and his metric cronies obviously don't understand that in the rough and tumble world of geology it's quite acceptable to denounce all climate scientists as liars, fools and frauds, that the bolshevik BoM tells us all lies every night and cooks its books quite literally. That their outrageous schemes are driven by the UN, the IPCC, and the secret World Guvvermint!

      He doesn't understand that all this is just polite academic discussion in a climate of mutual respect - a principle upheld by all retired geologists and self-styled ANU alumnus.

      He's just dreadful!

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    7. John Nicol

      logged in via email @bigpond.com

      In reply to Andrew Vincent

      Andrew,

      Thanks for your comments and the links. I believe the link between cosmic rays and the possible formation of clouds is quite sound and is in fact observed in the well known devices used to detect cosmic rays, the cloud chamber. This is a device in which a super saturated - i.e. very humid atmosphere in a container, is maintained. The passage of a cosmic ray through the chamber causes condensation along the path of the ray because as it travels with high energy, the cosmic particle ionises…

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    8. Dianna Arthur

      Environmentalist

      In reply to Peter Ormonde

      "... and cooks its books quite literally"

      Releasing more of the dreaded CO2 - BoM's clearly laughing all the way to the bank.

      Mr O, Champagne writing, sir. I doff's me cap.

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    9. David Arthur

      resistance gnome

      In reply to John Nicol

      Mr Nicol, we have discussed climate science on various fora over the last few years. Rest assured that this has afforded ample opportunity to ascertain the value of your contributions.

      Clive Hamilton and ABC balance
      http://www.abc.net.au/unleashed/29880.html

      Warming denialism is in the political eye of the beholder http://www.abc.net.au/unleashed/3737156.html

      Flawed science and still a tax on carbon http://www.abc.net.au/unleashed/41386.html

      Dry parts of the planet to get drier…

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  6. Andrew Kerber

    Database Administrator

    Well, this seriously fails the first test, that being are my assumptions correct?. The article states that there is an increase in extreme weather. Guess what, there is no increase in extreme weather. 2012 was average in that regard. So, yet another theory is disproven because the people who came up with the theory forgot to verify their assumptions.

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    1. Andrew Kerber

      Database Administrator

      In reply to Felix MacNeill

      My evidence? Well, first of all, since they are making the claim they have to provide the evidence. But the information is freely available at noaa.gov, it just takes some time to go through it. It was also stated in the most recent IPCC report, and several other places. Anyone who is listening to any unbiased information on this topic should already know that.

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    2. Sherry Mayo
      Sherry Mayo is a Friend of The Conversation.

      logged in via Facebook

      In reply to Andrew Kerber

      Andrew - you really have to better than 'proof by assertion'.

      I had a quick look at the climate section of the NOAA website and what do I find but a video about 'extreme events in 2012' which gives a handy summary of all the extraordinary record breaking weather events in the US last year.

      Check it out: http://www.climate.gov/#climateWatch

      Your comment about the IPCC report is also mystifying. AR5 is not out, only leaked, but even so the cutoff for submitted papers was mid 2012 so it won't be saying anything substantial about 2012's weather extremes.

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    3. Michael Shand

      Software Tester

      In reply to Andrew Kerber

      So went to NOAA website and one of the first things that is shown is extreme weather in 2012....so what are you talking about?

      Are you reffering to this NOAA?

      http://www.noaa.gov/

      because when you simply search "2012" the first thing that appears is a video and information about what extreme weather we experienced in 2012

      So are you being outright dishonesty or willfully ignorant?

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    4. Felix MacNeill

      Environmental Manager

      In reply to Andrew Kerber

      I think the answer is provided adequately by Sherry and Michael.

      Of course, given that it was really a rhetorical question, there probably wasn't much point in their responses. I mean, all they offered was pesky evidence when the currency your original question was written in was predetermination.

      Perhaps if you were to repeat it a third time you would at least pass the Tweedle-Dum test.

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    5. Andrew Kerber

      Database Administrator

      In reply to Felix MacNeill

      Your pardon for me thinking you had the ability to go past the home page of a web site. The information from NOAA is summarized here:

      http://wattsupwiththat.com/reference-pages/climatic-phenomena-pages/extreme-weather-page/

      Which you wont like because of the person presenting the information. The data is extracted from the NOAA web site, and contain the NOAA logo as you will note. The only increase is a slight (1.89%) increase in precipitation. No positive trend in tornados, hurricanes, droughts, and floods. A slight decrease in droughts. Any more questions?

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    6. Peter Ormonde
      Peter Ormonde is a Friend of The Conversation.

      Farmer

      In reply to Andrew Kerber

      Just one question Andrew... why? Why do they do it these pseudo scientists and devillish deceivers?

      Seems all such a fuss when all the Governments need do is look up Tony Watts website and the Truth will be revealed.

      So answer me that one... simple really - but without it all your brilliance and omniscience falls in a heap really doesn't it?

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    7. Felix MacNeill

      Environmental Manager

      In reply to Andrew Kerber

      Andrew, you're partially right - it's not so much that I 'wont like' the person presenting the information as it is that I simply wouldn't trust a single word spoken by someone with Watt's demonstrated record for lying and misrepresentation.

      I don't need a proven liar to explain something to me as i can work it out for myself, based on actual evidence.

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  7. Sholto Maud

    Database coordinator

    This discussion, and others like it on this website seems to be around the modelling & data rather than running the models themselves. This might be because we don't all have access to the software that can run the model.

    Personally I would benefit from embedding a model simulation platform within the article/website. In this way we could discuss the modelling itself & change the parameters and run a simulation for our own verification/edification.

    I've had some success embedding the simulation platform (link below) into a blog page. I'd like to see theconversation.com provide a similar service to help focus discussions more.

    http://insightmaker.com/

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  8. Dianna Arthur

    Environmentalist

    The necessity of continuing to publish articles such as this is clearly demonstrated by the number of comments that have had to be removed by the forum moderator - maybe those who have had their comments deleted could spend some worthy time reading the plethora of data from sites such as CSIRO, BoM, NASA, IPCC instead of relying on climate denial rhetoric.

    I have always found study and research as an expedient path to informed opinion.

    Or may be the 'moderated' were simply being rude instead of ignorant.

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    1. takver takvera

      Journalist and Editor at Indymedia

      In reply to Dianna Arthur

      There is an old internet maxim: "Don't feed the trolls". Debating them on tangential subjects distracts from the subject of the article at hand. It is one of the ways to muddy the waters of debate. Thank you moderators. Now, back to how changes in the jet streams can influence the frequency and intensity of extreme weather events...

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    2. Felix MacNeill

      Environmental Manager

      In reply to takver takvera

      takver, I'd like to to organise a counter-conspiracy to the persistent littering of the trolls. I'm assuming it would be unbearable to simply leave everything unanswered - I guess on the fear that some innocent passerby might come across the site and conclude that nobody had been able to answer their apparently profound and truthy arguments...

      There are just two problems:
      (1) everybody would have to join [given that we're all obviously part of some pinko-greenie-commie-world government-UN-conspiracy that should, in theory, be simple enough]
      (2) we'd have to agree a twenty-character or more standard empty response to the empty posts.

      My personal suggestion would be based on Peter Ormonde's past references to Napoleon and the metric system. Perhaps if everybody simply posted something like:

      'Sean/John/Gerard/etc. it was all caused by Napoleon imposing the metric system on us, so there's nothing that anyone can do about it now.'

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    3. John Nicol

      logged in via email @bigpond.com

      In reply to Dianna Arthur

      Dianna,

      Your comment is very relevant to this whole debate on climate change. and global warming. It is necessary to engage with these groups of scientists to understand what they are doing and why they take the approach they do.

      About seven years ago I began to take an interest in Global Warming - as it was known as then - and wrote to several of the climate groups in Australia including those at UNSW, Melbourne, ANU and CSIRO - seeking references to articles on the physical effects of carbon…

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    4. Peter Ormonde
      Peter Ormonde is a Friend of The Conversation.

      Farmer

      In reply to John Nicol

      Good Fun Mr Nichol... no no no ... this is a plot and a conspiracy far beyond human comprehension or belief!

      And yet you alone - after just a few reads of the scant evidence available were able to see through their tissues of lies , their ineptitude and false data.

      Thank God we have men with your vision and ability to expose the plotters.

      But sadly while you go to enormous lengths here to finger their fibs - there's none of the "why" promised in your opening paragraph. Why are these…

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    5. Felix MacNeill

      Environmental Manager

      In reply to John Nicol

      No John, lying in the face of grave danger is not fun - it is deeply irresponsible and morally reprehensible. This isn't a fair debate in science. You have no right to any respect.

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    6. Dianna Arthur

      Environmentalist

      In reply to John Nicol

      I am humbled, after my tertiary studies beginning in the 80's, you have managed, in a scant 7 years of phone calls and letter writing, cut through to a vision that has eluded yours truly.

      You see this:

      http://tinyurl.com/bu3yx3n

      Whereas I can only see this:

      http://tinyurl.com/cnbw6lu

      The only thing for me to do is reiterate Mr Ormonde's cutting question:

      Why? Why would all science organisations from NASA through to our own BoM claim AGW? What do they have to gain?

      When you have so adroitly stripped away their royal garments to reveal these august institutions are all, at worst, unconscionable liars or at best complete and utter fools.

      So grateful, that you have set me straight on all this climate change nonsense and made me cognizant that I have wasted almost 30 years of work and study.

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  9. Michael Shand

    Software Tester

    Brilliant Article, thank you for sharing

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  10. William Hughes-Games

    Garden weed puller

    It is true that the waves were amplified in terms of their amplitude but were weakened in terms of their strength. They remind me pf a top that begins to wobble as it slows down. The Polar Jet Stream which marks the border between the Arctic and temperate air bodies has slowed down. This indicates that the Polar Hadley Cell in which air radiates heat to space, becomes dense and spreads south over the land to rise at about 60 degrees north, is weakening. It is the rate of rotation of the Polar…

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    1. John Nicol

      logged in via email @bigpond.com

      In reply to William Hughes-Games

      William that ius a very interesting take on the warming of the polar regions. However, I woinder if you could give us a bit more detail, particularly on the reversal of the Hadley Cell. In my ignorance, I would have thought that the poles would never become warm enough to promote an upward flow of air against the "drag" of the warmer air over the tropics and mid latitudes, where upward convection would, I thought be strongest?
      John Nicol

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