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back to article No increase in droughts since 1950, say boffins

An international alliance of climate scientists says that contrary to the general perception, and despite widely-reported rises in global temperature towards the end of the 20th century, there has in fact been no measurable increase in droughts over the past 60 years. Writing in heavyweight boffinry journal Nature, the team …

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  1. John Smith 19 Gold badge
    Thumb Up

    So IPCC model *simplistic* rather than simple.

    And hence "conservative" in its over prediction. Which is fine if *nothing* better exists.

    Note the reference for the "better method" (Penman) dates from *1948*. And on another historic note "and may help to explain why palaeoclimate drought reconstructions based on tree-ring data diverge from the PDSI-based drought record in recent years," presumably because the tree rings record *actual* drought while PDSI calculates *expected* draught (that might not have happened).

    It's plausible that thismethod would be much more computationally demanding but it's hard to believe that *only* now has the MIPS been available to do this.

    Thumbs up for someone refining the model and using "underlying physical principles," rather than some sort of derived proxy.

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    1. RICHTO
      Reply Icon
      Mushroom

      Re: So IPCC model *simplistic* rather than simple.

      Rather misleading to not also mention that the key effects such as Ice sheet melting, sea water rise and temperature rise have been under estimated. For instance we are now on target for a 4-7 degree rise by 2100 rather than the 2 degrees that was previously declared as 'must be avoided at all costs'.

      The northern part of the Greenland ice sheet may be “very vulnerable to a warming climate,” and this could produce up to seven metres of sea level rise:

      http://www.nunatsiaqonline.ca/stories/article/65674greenlands_ice_sheet_headed_towards_extreme_melt-down_scientists/

      Bye Bye Florida and East Anglia is one small consolation I guess.

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      1. Sean O'Connor 1
        Reply Icon
        FAIL

        Re: So IPCC model *simplistic* rather than simple.

        Not sure where you get that we're on for a temp rise of 4-7 degrees from? If you look at CRU's own graph you can cherry pick any start and end points you want and the most you'll get is 2.5C per century (1980-2000). When are you expecting this massive increase in the rate of temp rise to start?

        http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.gif

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        1. Tom 7
          Reply Icon

          Re: So IPCC model *simplistic* rather than simple.

          No the most recent review of the data by the National Center for Atmospheric Research has said the MINIMUM rise will be 2.5C this century.

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          1. Sean O'Connor 1
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            Re: So IPCC model *simplistic* rather than simple.

            > MINIMUM rise will be 2.5C this century

            Really? That's the *minimum* the temperature is going to rise this century? Have you actually looked at the 12 years of data we've already got for this century? Not looking very good that prediction, is it?

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            1. Wilco 1
              Reply Icon
              Facepalm

              Re: So IPCC model *simplistic* rather than simple.

              Another denialist "there hasn't been any warming in the last decade"?

              http://www.skepticalscience.com/going-down-the-up-escalator-part-1.html

              Looking at just a decade is incorrect as it includes short term oscillations, so you can easily claim that it has been cooling every decade in the last 40 years, whereas the long term trend is clearly going up. And that trend is 0.27C per decade, ie. 2.7 degrees this century if warming doesn't accelerate. Given CO2 concentration is accumulating faster than ever, we are going to see warming much beyond 2.5 degrees.

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        2. RICHTO
          Reply Icon
          Mushroom

          Re: So IPCC model *simplistic* rather than simple.

          I got 4-7 degrees C from this weeks New Scientist magazine. Who I would consider a very credible and balanced / peer reviewed source.

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          1. Bronek Kozicki
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            Thumb Down

            @RICHTO

            "New Scientist magazine. Who I would consider a very credible and balanced / peer reviewed source."

            Gosh. That is naiivety taken to the highest degree, almost as bad as trusting politicians on expenses, or BBC on climate reporting. I subscribe to NS since I quite like their coverage on physics and cosmology (and few other things) but as far as climate goes, their agenda is bloody obvious, across the board.

            Also, NS is *popular* science magazine, not *peer reviewed* one. If it is to be "peer reviewed one" then why I do not see any actual scientists to do the reviewing listed here http://www.newscientist.com/people (or anywhere else)?

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          2. Anonymous Coward
            Reply Icon
            Anonymous Coward

            Re: So IPCC model *simplistic* rather than simple.

            "very credible and balanced / peer reviewed source."

            New Scientist is NOT peer reviewed

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        3. RICHTO
          Reply Icon
          Mushroom

          Re: So IPCC model *simplistic* rather than simple.

          New Scientist article is called "Climate change: It's even worse than we thought"

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        4. Anonymous Coward
          Reply Icon
          Anonymous Coward

          Re: So IPCC model *simplistic* rather than simple.

          The OP is quite correct in that the most recent forecasts are for a likely rise of circa 4 degrees Centigrade by 2100, and a possible rise of 7 degrees.

          See for instance: http://uk.reuters.com/article/2012/11/19/us-worldbank-climate-idUKBRE8AI00520121119

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  2. g e
    Coat

    Golly

    Do you think this will be covered on the BBC?

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    1. DrXym
      Reply Icon

      Re: Golly

      No because the BBC isn't in the business of cherry picking data to promote a denialist cause.

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      1. Anonymous Coward
        Reply Icon
        Anonymous Coward

        Re: Golly

        DrXym, you write that "the BBC isn't in the business of cherry picking data to promote a denialist cause".

        That makes it abundantly clear that, far from being a scientist or an engineer, you don't even have the slightest inkling of the scientific method.

        Every elementary book about science explains that, although no amount of evidence can ever prove the correctness of a theory, it takes only one piece of appropriate evidence to disprove it.

        Publishing news of a fact, set of facts, or experiment that tends to falsify a widely-held theory is something that all good scientists strive to do. (See Richard Feynman, passim, for example). And that could hardly be better described than "cherry picking data to promote a denialist cause".

        Furthermore, the very idea of "denialism" smacks of religion and politics; it is absolutely antithetical to science. In many human affairs, consensus and the opinion of the majority hold sway. In science, everyone in the world can believe that, say, the Sun goes round the Earth or that disease is caused by an imbalance of the humours. But one individual - Copernicus or Galileo, Pasteur or Semmelweiss - may contradict the whole of received opinion, and still be absolutely right while received opinion is absolutely wrong. (Even if he dies under threat of death, like Galileo, or confined in a lunatic asylum like Semmelweiss).

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        1. Spanners Silver badge
          Reply Icon
          FAIL

          Re: Golly

          " it takes only one piece of appropriate evidence to disprove it"

          That pretty much rules out a lot of the people that pretend that climate change isn't happening then. They continually seem to haul out irrelevant, inaccurate, out of context and/or disproved information.

          "Furthermore, the very idea of "denialism" smacks of religion and politics;"

          It is notable that a large part of those people who do parctice this denialism are from the US, very conservative (even for the USA) and identify themselves as Christian.

          "may contradict the whole of received opinion, and still be absolutely right"

          The people you named were acting upon scientific information. They were not pushing an idea because the alternative would affect their friends profit margins. Neither were they even looking after their own jobs. They weren't even disagreeing with current theory because "God had promised" that the alternative would never come around.

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          1. Enrico Vanni
            Reply Icon
            FAIL

            Re: Golly

            "They were not pushing an idea because the alternative would affect their friends profit margins." I love how this is presented by the APG faithful as an argument that discredits 'the other side' when APG believers are (inadvertently or otherwise) promoting the cause that directly results in massive subsidies drawn from energy bills being paid to David Cameron's father in law to build wind turbines.

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        2. Anonymous Coward
          Reply Icon
          Anonymous Coward

          @Tom Welch

          "Every elementary book about science explains that, although no amount of evidence can ever prove the correctness of a theory, it takes only one piece of appropriate evidence to disprove it.

          Falsifiability is indeed part of the scientific process (Popper, passim)

          Furthermore, the very idea of "denialism" smacks of religion and politics; it is absolutely antithetical to science.

          Surely the absence of ANY appropriate evidence to the contrary (at this time) demonstrates that those who turn their backs on current theory (as in scientific theory rather than "just a theory") are indeed using religion and/or politics as the basis for their denialism?

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          1. Anonymous Coward
            Reply Icon
            Anonymous Coward

            Re: @Tom Welch

            What could you find that would falsify AGW theory?

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        3. DrXym
          Reply Icon

          Re: Golly

          "That makes it abundantly clear that, far from being a scientist or an engineer, you don't even have the slightest inkling of the scientific method."

          Actually I'm well aware of it and what it means to follow it. It means making observations, forming hypotheses and testing those hypotheses against the evidence. Those hypotheses that make accurate testable predictions become theories. It is a constant progression and evidence is at the heart of it.

          Thus it is no surprise to anybody that the IPCC or various scientific institutions should constantly appraise and reappraise their findings against the evidence and refine or change where necessary.

          However that is totally different from denialism where someone starts with an idea which is not supported by the evidence and eliminates, ignores or cherry picks to pretend their idea wins by default. It doesn't. We see this all the time in creationism, anti vaccine, 9/11 truthers, holocaust denial and global warming denial. Quote mining and cherry picking are favourites of denialists since they can rip a quote out of context and sometimes even pretend the authors support their cause. This article is just another example in a long line spouted by this site of late which does exactly that.

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          1. Anonymous Coward
            Reply Icon
            Anonymous Coward

            Re: Golly

            "However that is totally different from denialism where someone starts with an idea which is not supported by the evidence and eliminates, ignores or cherry picks to pretend their idea wins by default".

            That is a straw man, in the context of this discussion about the article in question. And your words could very plausibly have been used by the enemies of Galileo or Semmelweiss. Who decides whether a given idea " is supported by the evidence"? And once Tycho Brahe, Copernicus, Kepler, Galileo and others had made the sidereal measurements and worked out the mathematics to explain those measurements in terms of elliptical orbits, they were not "cherry picking" when they ignored the old arguments of Aristotle and Ptolemy. Those arguments were rendered irrelevant and worthless by the new knowledge.

            Of course, truth or falsity is always a subjective matter. It is open to anyone, even today, to insist that the Sun does go round the Earth, or that (as in the case of Feynman's old lady) "it is turtles all the way down". And those people can claim, with injured sincerity, that those who think otherwise are "ignoring or cherry picking to pretend their idea wins by default".

            In the case of climate science, it seems to me that a reasonably well informed, objective, impartial observer would think that the case is not proven either way. To start shrieking about "deniers" is to bring the tactics of the courtroom and the soapbox into science. Actually, never mind science; the principle of free speech means that we are allowed to say things that other people do not like. Otherwise, it means nothing at all.

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            1. James Micallef Silver badge
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              Thumb Up

              Re: Golly

              " a reasonably well informed, objective, impartial observer would think that the case is not proven either way"

              True, the case is not PROVEN either way, but most of the evidence points to (a) the earth is warming and (b) it woz us wot done it.

              As to what it means for the future, anyone's guess. As keeps getting pointed out by skeptics, the models we have are fairy crude, and they keep on getting things wrong, but every time a model gets wrong results it doesn't mean the whole model is invalid or the science is completely wrong. It is just an opportunity to refine the model and adjust the prediction, not throw the whole thing away. So maybe the earth is going to warm 1-2 degrees this century not 4-7, maybe Antartica's ice sheets will take 3000 years to disappear not 300.

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              1. Wilco 1
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                Re: Golly

                I wouldn't say the models are fairly crude - sophisticated is the right word. That doesn't mean they are perfect, but with computing power increasing fast, resolution and accuracy is improving. As others have already mentioned, the models are typically conservative and underestimate the effects of climate change. For example arctic ice is disappearing much faster than the models predicted. With the current rate of CO2 accumulation the chance of less than 2.5 degrees warming is pretty much zero.

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        4. Chris 3
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          Re: Golly

          I *do* have a scientific background, although in the biological sciences, rather than climate science. I *am* interested in a robust debate about theories.

          However over the years, The Register's coverage of climate change has been so consistently partial that I think 'cherry-picking' is a perfectly reasonable term to use in relation to its stories. Which is a shame, since I tend to skim through them these days, seeing that 'It's just Lewis being Lewis'. The man *appears* to be increasingly veering into 'kook' territory - which may be very unfair on him - I'm just judging from the nature of the writing.

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  3. fero

    I read this paper just an hour before reading Lewis's interpretation. Sadly the research in no way invalidates the global warming calculations. It just changes some of the predicted effects of global warming with regards to drought.

    The problem that the research looked at is the "Palmer Drought Severity Index" (PDSI) that is used to measure drought. The PDSI calculates drought by looking at the difference between precipitation and evaporation. The issue is with determining evaporation (can't be measured directly). The research increases the number of factors used to calculate precipitation.

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  4. John Smith 19 Gold badge

    "I read this paper just an hour before reading Lewis's interpretation.

    That would depend on how the information is incorporated (or deduced) from *existing* GCM's.

    *if* the PDSI is a standard *input* to those models then *all* models are over sensitive to climate change. If the "draught maps" are produced by GCM's evaluating the variables of the PDSI then their *logic* has to be refined to give more accurate outputs.

    "Sadly the research in no way invalidates the global warming calculations."

    That's a strawman argument. If PDSI is the input that may well move the size and scale of predicted draughts, invalidating *existing* predictions. If it's an output it is yet *another* refinement GCM modellers need to make to their systems.

    And BTW there is something called an "Evaporating pan" which works quite well as an evaporation gauge in meterology. However I'm not sure if it's used *widely* enough to be included in the standard mix of data fed into GCM's.

    10 8
    1. MondoMan
      Reply Icon
      Headmaster

      Aren't "draughts" the liquids that one quaffs at a pub?

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    2. John Smith 19 Gold badge
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      Unhappy

      4 up 8 down

      I'd love to know what your criticism is.

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  5. NomNomNom

    When new research finds changes will be greater than previously thought, climate skeptics dismiss it as alarmist. But when new research finds changes will be less than previously thought, climate skeptics accept it and cite it as evidence of prior alarmism. So it's alarmism either way.

    Furthermore the self-fulfilling myth that the IPCC is wildly alarmist also requires ignoring cases where the IPCC has underestimated changes. By pretending that the error always works to overestimate changes climate skeptics pretend that it's somehow beyond chance and must be deliberate. You will never find climate skeptics discussing IPCC model based predictions of Arctic Sea Ice which have underestimated the loss for example (http://blogs.scientificamerican.com/guest-blog/files/2012/09/naam-ice-12.jpg).

    25 13
    1. Anonymous Coward
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      Anonymous Coward

      NomNomNom, "climate skeptics"

      I don't think anyone is really sceptical that there is a climate. (Not a serious comment).

      Is the k of 'skeptics' intended to infer some sort of derogatory aspect upon climate sceptics?

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      1. Burb
        Reply Icon

        @Anonymous Coward: isn't 'climate skeptic' the term that they use to describe themselves? Also, I have noticed that they tend to use the US spelling of sceptic even if they are British). Given that they get their knickers in a twist about being called deniers I'm not sure what the correct term should be.

        1 1
      2. NomNomNom
        Reply Icon

        Yeah he's right I was using that well known derogatory letter 'K', the most heinous letter of the English alphabet.

        I swapped it in for the C hoping no-one would notice by devilish plan.

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  6. Anonymous Coward
    Thumb Down

    Wow

    So what we're seeing here is that over the course of 5 years, scientists have made yet another refinement of their theories.

    What is the world coming to?

    (but obviously it's more fun to use inflamatory words like "debunking" instead of celebrating the fact that the scientific method once again has been proven to work)

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    1. Tom 7
      Reply Icon

      Re: Wow

      its worse than that - the new and better measure of drought the Penman-Monteith equation "only slightly reduces the drying trend".

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  7. Frederic Bloggs
    Paris Hilton

    Can someone help me here?

    As an engineer and non-climate scientist, I am having some difficulty understanding how it is that increasing temperatures will cause drought in a world whose surface is predominantly water.

    As far as I can see increasing temperature -> increased evaporation from the seas -> more water content in the atmosphere -> more "weather" (as it is the latent heat of water that largely drives "weather") -> more wind -> more storms -> more rain (albeit in forms that one might not want or like) because land conditions (temperature, air pressure, geography etc) varies over a much greater range than that of the sea.

    Paleolithic evidence seems to suggest that the earth has been much hotter than now and that coincided with extensive *rain* forest, other plants and animal growth. Maybe we are burning the results to move current conditions toward those pertaining then - but it's probably not a very efficient method.

    Perhaps we should try harder?

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    1. RICHTO
      Reply Icon
      Mushroom

      Re: Can someone help me here?

      Erm - how about more evaporation from the land means that soil dries out quicker?

      5 4
    2. mathew42
      Reply Icon

      Re: Can someone help me here?

      I'm not knowledgeable about the science, but the "October global temps above average for 332nd straight month" article shows significant ocean warming off the south west coast of Western Australia, but rainfall in the southern part of WA has declined by 10% since the mid 1970s (search water.wa.gov.au for more details). Interestingly there is mention of a global change in atmospheric simulation in the ."How our rainfall has changed - The south-west" article.

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      1. Frederic Bloggs
        Reply Icon

        Re: Can someone help me here?

        But on the east coast the drought that had persisted for, I think, 7 years has well and truly broken, with full reservoirs, extensive flooding etc etc.

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        1. Tim99 Silver badge
          Reply Icon

          Re: Can someone help me here?

          @Frederic Bloggs

          The worst of the Australian East Coast flooding is further away from the South West of Western Australia than London is from Moscow.

          A CSIRO article on Australasian Ocean Currents, and how they help shape the climate around Australia can be found here: http://www.csiro.au/en/Outcomes/Climate/Understanding/AustralasianOceanCurrents.aspx

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      2. This post has been deleted by its author

      3. Tim99 Silver badge
        Reply Icon
        Pint

        Re: Can someone help me here?

        @mathew42

        I have lived in Western Australia for 20+ years. The rainfall has diminished dramatically in the SW. The area concerned is ~4 X the size of England. Our government has put 2 desalination plants on-line, and is discussing building more. The dams are hardly ever at more than 35% capacity - Some of this may be due to our population doubling (to 2+ million), but it is mostly caused by a decrease in rainfall, an increase in evaporation, and a reduction in run-off into water capture areas.

        This weeks edition of the ABC TV program "Catalyst" was devoted to the impact of warming across nearly all of the Continent - WA was particularly mentioned as having more than 1C warming in the last century, with a dramatic warming of the coastal oceans.

        Link (available until November 29): http://www.abc.net.au/iview/#/view/28262

        Beer, because that might be all of us sandgropers have to drink.

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        1. bugalugs
          Reply Icon

          Re: Catalyst 13:25

          I watched this program on iView last night. BOM statistics were presented, all showed a .7 degrees celsius average increase over 100 years, with which I have no difficulty. Dr.Jonica Newby spoke of the seas around Tasmania getting " hotter and hotter " then put her foot in the aforementioned sea, saying "mmm not too bad " before a wave came in causing her to withdraw her foot with a shrill giggle. The clear implication was that the water there was HOT. According to the program ( as it might be interpreted ), my chances of success in a cooked-prawn-direct-from-the-sea retail sales business based at Port Arthur, Tasmania, were 100,000 to 1.

          The program had an agenda. Was it guided by an ABC seminar of 28, whenever that was held ?

          Following the link may confirm/deny your prejudices. This program violated scientific integrity for propagandistic purposes, IMHO.

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    3. Charles Manning
      Reply Icon

      Re: Can someone help me here?

      Temperature means little. It is heat that matters. Temperature is a symptom, not a cause.

      Since melting ice takes a lot of latent heat, warming (ie the addition of heat) can just cause a lot of ice melting without any significant change in temperature.

      Likewise, evaporation takes heat and can reduce temperature. Modifications to vegetation coverage etc can cause a huge change in temperature.

      That really means any modelling based on temperature is pretty broken. Unfortunately temperature is all we can really measure. That means all the models are pretty badly screwed.

      4 1
  8. Jim Bob
    FAIL

    Prediction vs Observation

    " *More realistic calculations, based on the underlying physical principles that take into account changes in available energy, humidity and wind speed, SUGGESTS that there has been little change in drought over the past 60 years.*

    ...

    This flies directly counter to the most recent formal assessment by the UN

    …

    *More intense and longer droughts have been OBSERVED over wider areas since the 1970s* "

    What is more real/accurate, prediction or observation?

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    1. Naughtyhorse
      Reply Icon

      Re: Prediction vs Observation

      good question and i guess the answer depends on weather(hehe) or not you have a particular axe to grind.

      or to put it another way, depends on the degree of rose tinting on those specs lewis is wearing.

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    2. This post has been deleted by its author

    3. 0_Flybert_0
      Reply Icon
      Facepalm

      Re: Prediction vs Observation

      easy .. the UN / IPCC is a political organization, not a scientific one

      representatives of UN member governments, that do not need to be scientists at all, must approve the wording of IPCC final reports and it's recommendations

      IPCC does no original research .. produce no papers for peer review .. it parses bits and pieces from peer reviewed papers that support an assumption from IPCC's formation that CO2 increases causes global warming, that CO2 levels have not been this high in 1000s or 100,000s of years which is completely false .. it's a completely political agenda ..

      again, government representatives from China, Saudi Arabia, Nigeria, Russia, US .. every UN member that is interested has representatives that MUST approve the wording of IPCC reports before publication .. it is political and the end purpose is to impose a world-wide carbon use tax that will create trillions$ in new phony currency held by the world's central bankers on "behalf" of the UN

      If CO2 increase is a problem, the increased emissions are coming from China, the rest of Asia and India, which obviously are exempted from UN back *law* like the Kyoto treaty

      Meanwhile, the US, Canada and most of Europe have been using less fossil fuel and using *cleaner* fossil fuels and therefore slowing emitting less CO2 .. the US is emitting at about 1996 levels today

      IPCC's predictions are based in predictions of one nutcase physicist named James Hansen that were first published in 1981

      yet the best data .. NASA's various satellites shows the atmosphere has only warmed 0.13C since 1980-1981, which is also 0.13C rise over the 30 year average 1981 through 2010

      http://www.drroyspencer.com/latest-global-temperatures/

      that is 0.043C per decade increase in global temperatures, and the trend has been ZERO increase for over a decade .. and well within Hansen's own very narrow assessment of natural variability

      at the current OBSERVED trend, and there is good scientific evidence we might be entering a cooling trend over the next 20 years ( probably ) to 200 years ( based on long term solar cycles that are closely correlated to rises and falls in temperature over the last 9000 years ) ...

      at the current OBSERVED trend since 1979 ... by 2100 the world's atmosphere will be 0.39C warmer than today

      there has been ZERO increase in world wide cyclonic activity ( hurricanes / cyclones ) for the 25 years of good data available .. there has been ZERO increase in drought in intensity or number or area worldwide

      Sea levels are NOT rising at a rate to be concerned with ( actually lowered by 5mm in 2010 per the data ) and that little rise observed is due mostly to thermal expansion .. not ice sheet melt

      the sea level has been 2-3 meters higher in the last 9000 years a few times .. with out burning fossil fuels

      according to Hansen's 1981 paper .. we'd need to have a 2C rise in temperature from 1980 to MATCH the medieval warming period temperature .. and 4C increase to match the peak temperature of the last 2 interglacial cycles about 100,000 and 200,000 years ago

      the ONLY wide area with good ground temperature records is the USA over 80-100 years .. if you only count the stations with relible data over those 100 years .. there were WAY more daily high temperature records set in the 1930s ( 1936 in particular ) than any time since

      and the Continental US is only 2% of the Earth's surface .. not representative of global temperatures

      I don't deny at all that the world's atmosphere has warmed compared to 1910 or 1850 .. but it's completely accepted that it cooled from 1940 to 1978 despite steady increases in CO2 emissions from burning fossil fuels, and the satellite data since 1979 shows there is no significant warming tend we need to be concerned about for centuries .. the observed temperature changes do not correlate well to the steady rise in CO2 emissions and those temperature changes can be explained with known natural cycles .. mostly ocean current cycles

      what will NOT happen .. and has never happened in 100 of millions of years ... is RUNAWAY warming due to CO2 levels .as the computer models used .. predict will happen

      this theory that by 2100 we will have a 2C - 6C rise in temperatures is neither supported by observation, the ONLY valid way to do "climate science" .. and is not evidenced by the history of climate changes over the last 2 million years, or 10 of millions of years

      11 5
      1. NomNomNom
        Reply Icon

        Re: Prediction vs Observation

        "NASA's various satellites shows the atmosphere has only warmed 0.13C since 1980-1981, which is also 0.13C rise over the 30 year average 1981 through 2010"

        Well that's wrong. Even the graph you post a link too directly afterwards (http://www.drroyspencer.com/latest-global-temperatures/) shows far more than 0.13C warming since 1980-1981. If you don't believe me then follow the data file linked in that post which shows the trend is 0.14C/decade.

        ""at the current OBSERVED trend since 1979 ... by 2100 the world's atmosphere will be 0.39C warmer than today""

        At 0.14C/decade the atmosphere will be about 1.25C warmer than today by 2100.

        "according to Hansen's 1981 paper .. we'd need to have a 2C rise in temperature from 1980 to MATCH the medieval warming period temperature"

        Hansen's paper doesn't make any such claims. In fact Hansen has stated that we have probably already exceeded the medieval warming period.

        ".. and 4C increase to match the peak temperature of the last 2 interglacial cycles about 100,000 and 200,000 years ago""

        Again, Hansen's paper doesn't claim that. It's wrong. You are referencing ice core data that gives temperature for the poles but are comparing that to global warming, the globe. The last interglacials were not 4C warmer globally than present.

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        1. 0_Flybert_0
          Reply Icon

          Re: Prediction vs Observation

          on a running centered 13th month average we are about 0.13C above both the 30 year average and 1980

          http://www.drroyspencer.com/wp-content/uploads/UAH_LT_1979_thru_Oct_2012_v5.5.png

          maybe you can see that in the larger version

          and you obviously have not read Hansen's 1981 paper well .. however looking at fig.6 of it, I will correct my statement ... he shows the medieval warming period to be 0.5C to 1C warmer than 1980, and the Eemian Interglacial, the previous one to be 1C to 2C warmer than 1980 ..

          Hansen's predictions in 1981 for global warming trends, which were more conservative than IPCC AR4 2007 are already twice what the satelitte data shows since 1980

          scientifically speaking the sensitivity of atmospheric temperature to increasing CO2 is not as sensitive as James Hansen and his employee, infamous blog network operator Gavin Schmidt thought it was, and this is being shown by observation, as well as studies showing cooling effects ( such as the increased worldwide vegetation due to increased CO2 levels ) and negative forcing from increasing low cloud cover

          most people are some 8 years or more behind in better science than that released by Hansen's Goddard Center and the UN's IPCC reports .. Hansen is being discredited from within NASA and the rest of the scientific community because he is both a nutcase, and because he won't correct what is now shown to be incorrect

          Hansen's conclusions that black soot is largely responsible for Arctic Ice melt was spot on though .. for some reason you don't here much about that ..

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          1. NomNomNom
            Reply Icon

            Re: Prediction vs Observation

            "on a running centered 13th month average we are about 0.13C above both the 30 year average and 1980"

            You can't compare endpoints to determine a trend. A linear fit to the data shows 0.14C per decade warming, as reported by the scientist who compiled it.

            "and you obviously have not read Hansen's 1981 paper well .. however looking at fig.6 of it, I will correct my statement ... he shows the medieval warming period to be 0.5C to 1C warmer than 1980, and the Eemian Interglacial, the previous one to be 1C to 2C warmer than 1980 .."

            He shows the holocene maximum to be 0.5C to 1C, not the medieval warm period. The medieval warm period was cooler than that and in his recent papers he discusses present in terms of that. There has been about 0.6C warming in the land record since 1980 (the land record being what that figure 6 is depicting).

            "Hansen's predictions in 1981 for global warming trends, which were more conservative than IPCC AR4 2007 are already twice what the satelitte data shows since 1980"

            The satellite records are not surface land data. They are atmospheric land+ocean data.

            Hansen correctly predicted post-1980 warming before it happened. No-one else did. Hansen correctly predicted the order of magnitude of the warming. No-one else did. This he did at a time when surface temperature records were in their infancy and satellite records didn't even exist. At the time he predicted warming there had been - based on crude estimates - over a decade prior of no warming. He not only called the warming he got the order magnitude right.

            All the way climate skeptics were denying warming since 1980 had happened. Even past 2000 climate skeptics were being "skeptical" about whether the world had warmed since 1980. It wasn't until recent years that skeptics universally accepted the world has warmed since 1980.

            And yet they want to paint Hansen as being wrong?

            Hansen didn't get the amount of warming 100% correct, his predictions overshot by about 50%. What are the implications for climate sensitivity? 3C warming per doubling of CO2 instead of 4.5C.

            "Hansen is being discredited from within NASA and the rest of the scientific community because he is both a nutcase, and because he won't correct what is now shown to be incorrect"

            Ridiculous. He has a whole paper devoted to explaining the overprediction made in 1980, it's implications, etc. Calling him a nutcase...wow.

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  9. RonWheeler
    IT Angle

    IT?

    IT angle?

    Endless climate discussions on here to break up the fartproof underpants, car reviews. Never mind the 'feedback wanted' articles to feed the greed of channel partners selling cloud snake-oil. Seriously Reg, pick it up.

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