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Australia’s hottest year was no freak event: humans caused it

The Bureau of Meteorology has confirmed that 2013 was the hottest year in Australia since records began in 1910. Unusual heat was a persistent feature throughout the year. For the continent as a whole…

Australia saw extreme heat and bushfires in 2013. Flickr/Rossco ( Image Focus Australia )

The Bureau of Meteorology has confirmed that 2013 was the hottest year in Australia since records began in 1910.

Unusual heat was a persistent feature throughout the year. For the continent as a whole, we experienced our hottest day on record on January 7. Then January was the hottest month on record, and the 2012-13 summer was the hottest recorded for the nation.

The nation-wide temperature record set for the month of September exceeded the previous record by more than a degree. This was the largest temperature anomaly for any month yet recorded.

Averaged across all of Australia, the temperature for 2013 was 1.2C above the 1961-1990 average, and well above the previous record hot year of 2005 of 1.03C above average.

What caused these extreme temperatures? Climate scientists have a problem: because climate deals with averages and trends, we can’t attribute specific records to a particular cause.

But our research has made significant headway in identifying the causes of climate events, by calculating how much various factors increase the risk of extreme climate events occurring. And we have found sobering results.

We previously analysed the role human-caused climate change played in recent extremes across Australia.

For various record-breaking 2013 Australian temperatures, we investigated the contributing factors to temperature extremes using a suite of state-of-the-art global climate models. The models simulated well the natural variability of Australian temperatures.

Using this approach, we calculated the probability of hot Australian temperatures in model experiments. These incorporated human (changes in greenhouse gases, aerosols and ozone) and natural (solar radiation changes and volcanic) factors. We compared these probabilities to those calculated for a parallel set of experiments that include only natural factors. In this way, natural and human climate influences can be separated.

In our previous studies, we then applied an approach (known as Fraction of Attributable Risk) widely used in health and population studies to quantify the contribution of a risk factor to the occurrence of a disease. Health studies, for example, can quantify how much smoking increases the risk of lung cancer.

Using the climate models, the Fraction of Attributable Risk (FAR) shows how much the risk of extreme temperatures increases thanks to human influences.

In our earlier study of our record hot Australian summer of 2012-13, we found that it was very likely (with 90% confidence) that human influences increased the odds of extreme summers such as 2012-13 by at least five times.

In August 2013, Australia broke the record for the hottest 12-month period. The odds of this occurring increased again from the hottest summer. We found that human influence increased the odds of setting this new record by at least 100 times.

Recent extreme temperatures are exceeding previous records by increasingly large margins. The chance of reaching these extreme temperatures from natural climate variations alone is becoming increasingly unlikely. When we considered the 12-month record at the end of August, it was nearly impossible for this temperature extreme to occur from natural climate variations alone in these model experiments.

We have just completed a preliminary investigation of contributing factors for the record Australian temperature in the 2013 calendar year.

In the model experiments, it is impossible to reach such a temperature record due to natural climate variations alone. In climate model simulations with only natural factors, none of the nearly 13,000 model years analysed exceed the previous hottest year recorded back in 2005.

Australian annual temperature changes (relative to 1911-1940 average) for observations (dashed black) and model simulations with natural influences only (green) and with both human and natural influences (red). The grey plumes indicate the range of values simulated across nine global climate models used. Average Australian temperature anomalies are indicated for 2013 and the previous hottest year on record in 2005. David Karoly & Sophie Lewis

In contrast, in model simulations including both natural and human factors, such as increasing greenhouse gases, record temperatures occur approximately once in every ten years during the period 2006 to 2020. (On a mathematical note, as there is no instance in which the record hot yearly temperature occurred without human contributions, the FAR value is one.)

Probabilities of annual average temperatures for Australia from climate model simulations including natural influences only (green) and both natural and human climate influences (red) for model years 2006-2020. The vertical lines show the temperature anomalies observed in 2013 and in 2005 (the previous hottest year observed). David Karoly & Sophie Lewis

Clearly both natural climate variability and global warming from humans contribute to recent temperature records. Natural variability always plays a major role in the occurrence of weather and climate extremes. But in the case of our recent hottest year on record, human-caused global warming made a crucial contribution to our extreme temperatures.

Our extensive catalogue of 2013 record-breaking events in Australia occurred in a global context of increasing temperatures that must be considered. Globally, 2013 will likely rank as the 6th hottest year recorded.

So to return to our question, what caused the 2013 record hot year across Australia? Simply put, our climate has changed due to human activities. Recent extremes, such as this hot year, are occurring well outside the bounds of natural climate variations alone.

Join the conversation

162 Comments sorted by

Comments on this article are now closed.

    1. In reply to David Doe

      Comment removed by moderator.

    2. Ross Barrell

      Aikido Student

      In reply to David Doe

      Yes. Absolutely. Who'se going to beat down the doors of our moronic denialist government and get them to actually do something (albeit 20 to 30 years later than they should have) about this mess.

      Great article. Sweltering as I type these words - and I hope against hope that at this point something CAN be done.

      And I do have my denier bongo sheet handy. I have only started reading with breath abated...

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    3. Alice Kelly
      Alice Kelly is a Friend of The Conversation.

      sole parent

      In reply to David Doe

      David, This is a good question, and no doubt David Karoly has contributed to submissions before. Government receives clear concise reports like this when legislation is proposed. This is what I find most offensive, for years they've had the best advice and there are those, more often on the conservative side of politics who have the arrogance to think that there is no such thing as climate change.

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    4. Mark Pollock

      Analyst

      In reply to David Doe

      Maybe you could get a little party together to suspend the democratic process and then you could do all the "forcing" you like. In the meantime, our elected representatives have a clear mandate to dial back the fanatical alarmism.

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    5. Evelyn Haskins

      retired

      In reply to David Doe

      Using insulting terms to refer to people who do not agree with you proves nothing except the hollowness of your own argument.

      I don't think ANYBODY at all is denying that Climate changes, OR that human activity affects the climate.

      What thinking people are saying is that the piddling little measures that the Climate Change Alarmists are advocating will not solve any problems, that thinking you can build on the sand dunes and command the sea to not wash them away during storm surges, or build…

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    6. Felix MacNeill

      Environmental Manager

      In reply to Evelyn Haskins

      So, Evelyn, are you familiar with the term 'evidence'? You might like to run a few of your claimds past the concept some time.

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    7. David Doe

      Videogame Producer

      In reply to Evelyn Haskins

      "Using insulting terms to refer to people who do not agree with you proves nothing except the hollowness of your own argument."

      "Climate Change Alarmists"

      Delicious irony.

      Oh and if you really believe this :

      "I don't think ANYBODY at all is denying that Climate changes, OR that human activity affects the climate."

      You haven't been paying very close attention to your side of the "debate".

      Do try to keep up.

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    8. Mike Swinbourne

      logged in via Facebook

      In reply to Evelyn Haskins

      "....Using insulting terms to refer to people who do not agree with you proves nothing except the hollowness of your own argument...."

      "Denier" is not an insulting term - it's a descriptive term.

      "....I don't think ANYBODY at all is denying that Climate changes, OR that human activity affects the climate...."

      Then you think wrong Evelyn. Lot's of people think that.

      "....What thinking people are saying is that the piddling little measures that the Climate Change Alarmists are advocating ..."

      Climate change 'alarmists' huh? I guess that just proves the hollowness of your argument doesn't it?

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    9. Mark Pollock

      Analyst

      In reply to David Doe

      Who exactly is denying that the climate changes? Give us some names.

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    10. Mark Pollock

      Analyst

      In reply to Peter Banks

      The Prime Minister was quite clear about his intentions prior to the poll.

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

      Farmer

      In reply to Mark Pollock

      Yep - axe the tax and shell out taxpayers' money to encourage emitters to cut back.... silly as all heck that - but he is still araldited to the same reductions in emissions as the previous government - so if direct action doesn't do it we'll be buying carbon credits from somewhere... does this make sense to anyone at all?

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    12. Chris O'Neill

      Retired Way Before 70

      In reply to Evelyn Haskins

      "I don't think ANYBODY at all is denying that Climate changes"

      Some people deny that global average surface temperature, one of the most important parameters of climate, is changing.

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    13. Simon James Baring

      Student at the University of Melbourne at Melbourne school of Land and Environment

      In reply to Mark Pollock

      If by "fanatical alarmism" you mean 98% of the global scientific community who have proved humans are causing increasing temperatures and climatic extremes then the "dial back" approach of the current government is not democratic at all. Suppressing the majority would, in fact, align with some form of dictatorship.

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    14. R. Ambrose Raven

      none

      In reply to Alice Kelly

      "Alarmist" is a form of abuse frequently used by denialists to distract attention from the issue by personal attacks on those who see the need for effective action. Evelyn is clearely a climate change denialist troll. Evelyn should be pleased.

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  1. Chris O'Neill

    Retired Way Before 70

    Just came across this: http://en.wikipedia.org/wiki/Misuse_of_statistics which includes:

    1.7 Proof of the null hypothesis

    This is what denialists do when they say there has been no warming in 15=17 years. The null hypothesis is that there is no warming in 15-17 years and those clowns think they have proven it.

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    1. Mark Pollock

      Analyst

      In reply to Chris O'Neill

      I can't speak for all denialists, but for me, the null hypothesis is that the link between atmospheric CO2 concentrations and global temperatures is small to minimal. The 15 or so years of minimal temperature rise, during which C02 concentration continues to rise, implies it is true and that the model that predicted a continuing rise are incorrect.

      Your misuse of statistics list is interesting. It reads like a summary of Climategate and other scandals.

      Discarding unfavorable data - hide the…

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    2. Chris O'Neill

      Retired Way Before 70

      In reply to Mark Pollock

      "but for me, the null hypothesis is ... The 15 or so years of minimal temperature rise"

      QED

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    3. Henry Verberne

      Once in the fossil fuel industry but now free to speak up

      In reply to Mark Pollock

      Again all the assertions without any evidence to back them up.

      Until you do, with credible references to peer-reviewed science your views do not impress in the slightest.

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    4. Mark Pollock

      Analyst

      In reply to Chris O'Neill

      Like the claim that a record temperature demonstrates a human cause, your vacuous response demonstrates nothing.

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    5. Mark Pollock

      Analyst

      In reply to Henry Verberne

      Well, where's the Gergis paper then? Wasn't that peer reviewed?

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    6. David Arthur

      resistance gnome

      In reply to Mark Pollock

      Null hypothesis: {no temperature rise ...
      + no ocean warming ...
      + no sea level rise ...
      + no ice mass decrease ...
      + no permafrost thaw.}

      Err, perhaps you don't know how to construct an appropriate null hypothesis?

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    7. Mark Pollock

      Analyst

      In reply to David Arthur

      It isn't whether these things are happening. It's the degree to which they are happening. It's all about the degree. For example, the so called "Angry Summer" supposedly the hottest on record. How angry was it? A mere 0.1 degrees hotter than the previous Angry Summer. Do you imagine that. It's possible to measure a continental temperature to that degree of accuracy? What's the error?

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    8. Henry Verberne

      Once in the fossil fuel industry but now free to speak up

      In reply to Mark Pollock

      Mark I repeat, please give me some peer-reviewed links to support your claims. Snide remarks count for very little.

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    9. Chris O'Neill

      Retired Way Before 70

      In reply to Mark Pollock

      "the claim that a record temperature demonstrates a human cause"

      Who claimed that?

      "your vacuous response"

      What a hypocrite. The only one who's vacuous is the one claiming this null hypothesis "15 or so years of minimal temperature rise" is proven.

      It's just incredible. I point out that denialist clowns think they prove a null hypothesis and then you come along immediately and do it yourself.

      You just couldn't make this up.

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    10. Mark Pollock

      Analyst

      In reply to Chris O'Neill

      You don't have to prove the null hypothesis.

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    11. Mark Pollock

      Analyst

      In reply to Alice Kelly

      I loved the first article. To paraphrase - "global warming is making it really cold in the USA". I like the graph too. Particularly the S-mid latitudes going back to 1880. We know from this article that temperature records in Australia only started in 1910. Where did they get the data from? Brazil?

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    12. Chris O'Neill

      Retired Way Before 70

      In reply to Mark Pollock

      "A mere 0.1 degrees hotter than the previous Angry Summer."

      0.17 degrees hotter actually, but accuracy is of no significance to denialists.

      So 0.17 degrees hotter in 8 years or 2 degrees per century.

      Yeah, that's "mere" all right.

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    13. Chris O'Neill

      Retired Way Before 70

      In reply to Mark Pollock

      "You don't have to prove the null hypothesis."

      No shit Sherlock. That wouldn't have anything to do with the reason for having a null hypothesis being to DISprove the null hypothesis?

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    14. David Arthur

      resistance gnome

      In reply to Mark Pollock

      "You don't have to prove the null hypothesis."

      Null hypothesis: {no temperature rise ... NULL HYPOTHESIS REJECTED
      + no ocean warming ... NULL HYPOTHESIS REJECTED
      + no sea level rise ... NULL HYPOTHESIS REJECTED
      + no ice mass decrease ... NULL HYPOTHESIS REJECTED
      + no permafrost thaw ... NULL HYPOTHESIS REJECTED.}

      Err, perhaps you don't know how to conduct statistical tests either?

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    15. Alice Kelly
      Alice Kelly is a Friend of The Conversation.

      sole parent

      In reply to Mark Pollock

      Yes Mark, The polar vortex has turned into an extended loop which extends right down into the US bringing snow and cold, at the part of the now very loopy line where it is extended back up towards the pole there will be heat , which brings drought to northern areas at the very same time. It used to be a moderate wavy line.
      http://www.google.com/hostednews/afp/article/ALeqM5i7KyWtsU2VtCqbv3Z1Ma8SuMNPcQ?docId=0ddb9d00-f06a-4562-b335-5c4afd848e24
      The point being if you actually bothered to read anything other than crap, you'd know this already. You would have seen the heat rise in the arctic during the "pause", where did that come from Mark, tell me, what natural variation caused it.
      Temperature records pre 1910 in Australia were not complete or reliable, are you suggesting BOM "plants" some temperatures from Brazil. Resorting to hysterical snide abuse means what, you are getting a little worried?

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    16. Geoff Henley

      Research Associate in Health Statistics at Flinders University

      In reply to David Arthur

      David,
      The NULL HYPOTHESIS is not that there is no temperature rise or no sea level rise etc.

      The NULL HYPOTHESIS is that any observed changes do not fall outside that which can be explained by natural variation.

      This is different from what your post indicates.

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    17. David Arthur

      resistance gnome

      In reply to Geoff Henley

      "The NULL HYPOTHESIS is that any observed changes do not fall outside that which can be explained by natural variation."

      Thanks Mr Henley. It so happens that the null hypothesis as you pose it is what is being tested by Dr Lewis and Prof Karoly.

      It also happens that there have been several previous attribution studies.
      Stott et al 2010,"Detection and attribution of climate change: a regional perspective"
      Gillett et al 2011 "Attribution of polar warming to human influence"
      Unger et al (2010…

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    18. Mike Swinbourne

      logged in via Facebook

      In reply to Geoff Henley

      "....The NULL HYPOTHESIS is that any observed changes do not fall outside that which can be explained by natural variation...."

      Wrong Geoff. Call yourself a reseach officer?

      Your 'null hypothesis' contains an assumption about causality that requires evidence to support it - therefore it is not a null hypthesis at all.

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    19. John Doyle

      architect

      In reply to Mark Pollock

      Recall the Maunder Minimum "Little Ice Age" was only a half a degree colder than the average. We are dealing in small numbers but with possible big effects.
      Right now we could be actually in a cooling cycle which is being countered by global warming. Even John Hamaker's vegetation based theory is worth looking at re the recurrence of ice ages.

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    20. Mark Pollock

      Analyst

      In reply to Alice Kelly

      Temperature records prior to 1910 May or may not be complete or reliable but they are still used to construct the major global temperature data sets. I wonder how this is so. In particular, there are few non Australian or non New Zealand records for the mid southern latitudes for this time. If these records are so unreliable then how is it that they are so widely used?

      As for they other stuff, you're still saying that global warming makes everything very very cold, that is, when it's not making things very very hot.

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    21. Mark Pollock

      Analyst

      In reply to David Arthur

      No, that's not what I said. Go and read again and if you have anything intelligent to say I will respond.

      I appreciate that this is probably not your area but you might have a look at what the null hypotheses actually means. First up, you never test the null hypotheses, you test the theses. If this test fails you assume the null hypotheses is true.

      Nothing that you have said makes any sense but I think you're getting close.

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    22. David Arthur

      resistance gnome

      In reply to Mark Pollock

      Thanks Mr Pollock.

      "The 15 or so years of minimal temperature rise, during which CO2 concentration continues to rise, implies it is true and that the model that predicted a continuing rise are incorrect."

      Even MINIMAL temperature rise by itself suffices to reject the null hypothesis as you have postulated it ("null hypothesis is that the link between atmospheric CO2 concentrations and global temperatures is small to minimal".

      For a start, small to minimal is NOT denial of an effect; the issue then becomes "how big an effect"? For this, we have oodles of associated evidence (rising sea levels, thawing permafrost and melting ice) such as that on which I believe we have both commented in these pages.

      Regarding the comment that nothing I have said has made sense to you, perhaps that says more about you than me?

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  2. Comment removed by moderator.

    1. Russ Hunter

      Healthcare Professional

      In reply to Mark McGuire

      Mark McGuire, you even do your fellow climate change deniers a disservice. That is quite possibly the most pathetic attempt at a cogent argument I have ever seen put up by a denier, which is no small feat, I can tell you.

      If that's an example of your work you should probably take up something else. Perhaps you could get coffees at the IPA if you want to be of service?

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  3. Mark Pollock

    Analyst

    Australian climate records did not begin in 1910. Also, a model, no matter how state of the art a model is, it is not an experiment. An experimental model is a tautology.

    Which brings us to the Fraction of Attributable Risk tool. This might have some value in epidemiology, where actual observations made on an affected group and a control group are being compared. It is probably useless when comparing two sets determined by many subjective assumptions.

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    1. Henry Verberne

      Once in the fossil fuel industry but now free to speak up

      In reply to Mark Pollock

      Yes you are quite correct Mark. We really should go back to at least to 1788, when white settlement began. Then we''ll have some impeccable statistics of temperatures. That will surely satisfy all your objections?

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    2. Mark Pollock

      Analyst

      In reply to Alice Kelly

      Lysenkoism comes to mind. I understand it was consensual. Of course, they had to suspend the democratic process first. Iam sure there were plenty of peer reviewed papers published in the relevant press.

      Anyone for eugenics? Not taught much any more but it was very very popular up until about the late thirties.

      Closer to home was the idea that stomach ulcers were caused by stress. That was pretty consensual too. The MMR vaccine Autism link was peer reviewed and only refuted by a journalist. The relevant scientists just let it flow. I am sure there are others.

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    3. Mike Swinbourne

      logged in via Facebook

      In reply to Mark Pollock

      "....Australian climate records did not begin in 1910..."

      This is a perfect indication of why people like Mark Pollock are nothing more than deniers who should be forever banned from commenting and told to go away and peddle their crap elsehere.

      You asked this quesiton the other day Mark, and you were given the answer. Take your zombie lies and put them where the sun doesn't shine.

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    4. Alice Kelly
      Alice Kelly is a Friend of The Conversation.

      sole parent

      In reply to Mark Pollock

      None of these things were extensively studied to the extent that climate change has been. No Major scientific finding has been found to be incorrect because science is far more rigorous now. The MMR vaccine theory was one study which has been proved to be incorrect for a very long period, Japan which didn't use it had the same rates of autism, despite this conspiracy theories amongst some persist. Stomach ulcers have been proved to be caused by bacteria (science).
      None of these examples represent the way a massive body of evidence has lead to the theory, and now fact of AGW.
      Perhaps you could explain why sheet ice is being lost at a rapid rate.
      Temperatures of combined atmosphere and oceans are increasing rapidly.
      Ocean Acidification has risen by 40%
      The polar vortex has become deformed.
      WE have just had the hottest summer on record despite not being in an El Nino
      ETC.

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    5. Mike Swinbourne

      logged in via Facebook

      In reply to John Phillip

      "....I wonder if that has an effect on the rate of temp change?..."

      Well done John. You are finally thinking like a scientist. That's exactly the sort of question that scientists ask all the time.

      But guess what? When they ask these questions, the first thing they do is a literature search to see what work has already been done.

      Perhaps you could do the same. Try reading some science. You might be surprised what scientists already know, and what you won't find at your usual denier blogs.

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    6. Mike Swinbourne

      logged in via Facebook

      In reply to John Phillip

      ".... That's a bit presumptuous, don't you think?..."

      Not at all. I guess if you are interested in reading lies that confirm a pre-existing ideological viewpoint, rather than reading evidence based science, then places like wattsupmybutt are just the thing. Me - I prefer journal articles.

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    7. Mark Pollock

      Analyst

      In reply to Mike Swinbourne

      It's not a question. It's an assertion.

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    8. Mustafa Epstein

      Political Scientist

      In reply to John Phillip

      Why is it imposibel to find out which actual weather stations are included in the BoM's figures.

      Why the secrecy.

      Why no access to the data.

      And you claim I'm fiddling with their very own figures which disproves what they say ??????

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  4. Jane Middlemist

    citizen

    Thank you to the authors.
    An avid reader, I have been convinced for some time now that climate change is real and that it is going to get warmer, and I've moved on.
    These days I spend a lot of time thinking about what can be done to ameliorate the situation and whether much will be done at all because action might interfere with various vested interests - political, business (profits) etc.

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    1. Jane Middlemist

      citizen

      In reply to Henry Verberne

      Thank you Henry.
      The implications of global warming are very real to us living, as we do, in the Blue Mountains of NSW (for the past 23 years) in a century old timber house. Last year the fires were really terrible and a surprise in October. (The previous October we had snow). All a bit unsettling. We seek all the (reliable) information we can get! :-)

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    2. David Arthur

      resistance gnome

      In reply to Henry Verberne

      "... within the power of the large emitters but they will not exercise that power willingly as they prefer BAU so governments have to price carbon or ..."

      Perhaps there is a dilemma for the large emitters in that they are accountable to their shareholders to maximise share holder return, a duty they carry out within the current taxation environment. Any preference they may for 'BAU' is within that context, so that if there was a change imposed in their largest recurrent expense, taxation, perhaps…

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    3. Jane Middlemist

      citizen

      In reply to Alice Kelly

      HI Alice, yes I see the forecast is for plenty of rain until the end of January. Phew! Then we only have to navigate through February, buckets and hoses at the ready; and we'll be all set (like the proverbial jellies) until next Spring; fingers crossed. As for El Nino. I'm just hoping for El-No-No.

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  5. David Arthur

    resistance gnome

    Thanks for this article, Dr Lewis and Prof Karoly.

    I've got a couple of questions from the paragraph: "In the model experiments, it is impossible to reach such a temperature record due to natural climate variations alone. In climate model simulations with only natural factors, none of the nearly 13,000 model years analysed exceed the previous hottest year recorded back in 2005."

    1) did the model experiments discussed here reproduce anything like a reconstruction of Holocene global average temperature trends?

    2) are you here stating that modelled 2005 temperature is higher than any modelled temperature for the preceding 13 millennia, or just that departure from "natural" temperature trend exceeds any year in that preceding period?

    If you've "just completed a preliminary investigation", I presume the work described in this article is not yet published? Thanks.

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  6. Michelle Burrows

    logged in via Facebook

    You should contact Frank Lansner and share your unadjusted original data. Unadjusted original data is hard to come by. Frank is eager to gather as many unadjusted original data readings as he can. He's trying to preserve the unadjusted original data readings before fiddling with readings to produce a warm outcome becomes the norm.

    The Original Temperatures Project

    http://wattsupwiththat.com/2014/01/06/the-original-temperatures-project/

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    1. Mike Hansen

      Mr.

      In reply to Michelle Burrows

      Hilarious.

      Michelle is attempting to promote a conspiracy theory. Even though all the data is freely available to download.

      But Michelle manages to shoot herself in the foot by linking to the site of climate crackpot Anthony Watts whose much vaunted "paper" that was to be published on the temperature record died an unseemly death because the incompetent Watts and his team of deniers were unaware they need to make "time of observation" adjustments to the data.

      http://www.skepticalscience.com/watts_new_paper_critique.html

      Even the "auditor" Steve McIntyre jumped ship on that one.

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    2. Doug Hutcheson

      Poet

      In reply to Mike Hansen

      Not to mention that Watts was part of the BEST project. He firmly believed that temperature records were skewed and jumped at the chance to prove it, even saying in advance he would stand by the results of the project. When the results confirmed the reality of Global Warming, he suddenly lost interest and decided not to support the findings publicly.
      Scepticism means doubt, but willingness to be swayed by the evidence. Denialism means ignoring any evidence contrary to a prior, stated position. Which camp does Watts (and, thus, WUWT) belong to? You get one guess.

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    3. Geoffrey Sherrington

      Surveyor

      In reply to Sophie Lewis

      Sophie,
      And since near their inception the whole group of CMIP5 models and precursors have run too hot.
      They should not be used for speculation like yours until the causes of error are found and repaired.
      There is a problem with the treatment of aerosols in some models, e.g. as noted by Nic Lewis in public emails with Dame Julia Slingo of the UK Met Office re HadCM3.
      Dame Julia had not provided a credible response to Nic's answers last time I checked. Until that is sorted, the UK Met Office model…

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  7. Andrew Kerber

    logged in via Facebook

    This article is actually funny. The correct term for an argument using models is a circular argument, not peer reviewed science. The models are programmed to show more rising temperature due to human influence, so they show more rising temperature due to human influence. This article is not science in any sense of the word, and thus should not pass peer review.

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    1. Andrew Kerber

      logged in via Facebook

      In reply to Sophie Lewis

      The models are not forced by anything, they are computer programs and respond as they are programmed. They are programmed to show increased temperature when the numbers for CO2 or other green house gases are increase, therefore they show increased temperature. They prove nothing, other than they work as programmed.

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    2. Andrew Kerber

      logged in via Facebook

      In reply to Mike Hansen

      Im afraid I dont see your point. Computer models are programmed to produce a set of results based on a set of inputs. That's how computer programs work. To claim otherwise is simple ignorance of computer science. It doesnt matter how fancy the program is, they all boil down to the fact that a given set of inputs will always produce a given set of outputs. Thats why you cant use them to conduct valid scientific experiments, if you know what data went into the program you will always know what data comes out of the program.

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    3. Mike Hansen

      Mr.

      In reply to Andrew Kerber

      I am a computer scientist. You are talking arrant nonsense.

      All statistical analysis and modelling is done via computer. Where have you been for the last half century?

      "They are programmed to show increased temperature when the numbers for CO2 or other green house gases are increase, therefore they show increased temperature" is a conspiracy theory which I assume you have acquired through an addiction to climate crank blogs.

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    4. Account Deleted

      logged in via email @drdrb.net

      In reply to Mike Hansen

      Mike, Andrew is just responding as he is programmed to. You'd have better luck arguing with ELIZA.

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    5. Peter Banks

      retired Civil Engineer

      In reply to Andrew Kerber

      So, by extension of your argument that the output of computer models is pre-determined by the author, perhaps we would be unwise to rely on anything calculated using a computer model?

      Pity, looks like we'll have to return to hand calculation of structural strength in buildings, of pipe sizes and cable sizes in water and electricity grids, etc.

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    6. Geoffrey Sherrington

      Surveyor

      In reply to Sophie Lewis

      Sophie, see again Nic Lewis re HadCH3. This model appears to have been programmed to avoid a low climate sensitivity result, which is rather similar to saying that it was programmed to show more rising temperatures.
      Meaning that at constant GHG concentration and forcing assumptions, a high ECS or TCR output will forecast hotter temperatures ahead than a low output.

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    7. Andrew Kerber

      logged in via Facebook

      In reply to Mike Hansen

      Yes, you are correct. Statistical analysis and modelling is done by computer. It is done that way precisely because a given set of inputs will produce a given set of outputs. If anything, your statement supports my point.

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    8. Andrew Kerber

      logged in via Facebook

      In reply to Peter Banks

      Nope, didnt say that either. We know that our models for structure and strength are very good, and all major variables are handled. We dont know that for climate, because if we did the forecasts would be better. Also, the models to which you refer are not used to claim that actual science experiments are being done with them. They are used because we know that a given set of inputs, the correct numbers for the type and number of materials for example, will always produce a correct or near correct set of outputs.

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  8. Craig Myatt

    Industrial Designer / R&D

    That is really very clearly articulated, fantastic science which can energise responsible policy action. Thanks!

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    1. Doug Hutcheson

      Poet

      In reply to Craig Myatt

      Craig, "which can energise responsible policy action": if only you were right. I see little energetic policy action on our horizon, sadly, in spite of good science like that which underpins this article. When the Murdoch empire is against climate action, do not expect Mr. Average Bloke In The Pub to be well-enough informed to agitate for action.
      We are all at the mercy of a few opinion makers in politics and industry. When these masses align, policy action gravitates to the greatest possible contrarianism. What a way to run a country!

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    1. James Whitmore

      Editor at The Conversation

      In reply to Michelle Burrows

      Lucky for us the authors did just that!
      "Using this approach, we calculated the probability of hot Australian temperatures in model experiments. These incorporated human (changes in greenhouse gases, aerosols and ozone) and natural (solar radiation changes and volcanic) factors. We compared these probabilities to those calculated for a parallel set of experiments that include only natural factors. In this way, natural and human climate influences can be separated."

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    2. Andrew Kerber

      logged in via Facebook

      In reply to James Whitmore

      Um no, they didnt conduct any experiments at all. They ran computer programs (aka, models). If they had been able to conduct experiments, this would be actual science. Since all they did was use models, which must respond as programmed, they proved nothing at all. Well, they did prove that their program works as they expect it to.

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    3. Mike Hansen

      Mr.

      In reply to Michelle Burrows

      A greenhouse effect denier - now that is hardcore denial.

      The first paper on the list.
      "Deep Solar Activity Minima, Sharp Climate Changes, and Their Impact on Ancient Civilizations"

      Hilarious. A paper showing that changes in insolation have affected climate in the ancient past. Who knew?

      Maybe this guy.
      http://en.wikipedia.org/wiki/Milankovitch_cycles

      Or maybe these people.
      http://www.skepticalscience.com/What-would-happen-if-the-sun-fell-to-Maunder-Minimum-levels.html

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    4. Felix MacNeill

      Environmental Manager

      In reply to Andrew Kerber

      So, Andrew, how would you conduct a laboratory experiment to test climate change in Australia? What 'experiment' could you run that would account for all the variables of an actual climate in action? If you want, in effect, to do 'in vitro' you're going to need a very big beaker!

      As others have pointed out, all science these days relies heavily on computer modelling (short of goat entrails, that's really the only way you can predict anything, which tends to be the big payload of science!). So…

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    5. Andrew Kerber

      logged in via Facebook

      In reply to Felix MacNeill

      So long as the parameters are correct.... That of course is the big question with models. How exactly did they validate these models? Is this one of the 98% of the models that predicted the temperature increase at roughly 100% higher than what it has been? And how do they prove the skillfulness of this model? Normally you compare it to the real world measurement, but what real world measurement do you compare it to here? In any scientific experiment you must have a control. What is the control? They have no way of proving their result correct outside of their model, and their models dont have a great record of past accuracy. Goat entrails might really work better actually, and the idea that this model manipulation proves anything in the real world is ludicrous.

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  9. Geoff Henley

    Research Associate in Health Statistics at Flinders University

    As usual, the editors an The Con obsess over what is happening in Australia and ignore what is happening globally. The fact that many countries in the Northern Hemisphere have recently experienced or are experiencing some of the coldest winters for decades is completely ignored here.

    It is after all 'global warming' not 'Australian warming'. Globally, temperatures have pretty much flatlined for well over a decade. On the back of some rather tenuous evidence, we are supposed to believe that all…

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    1. Doug Hutcheson

      Poet

      In reply to Geoff Henley

      Geoff, as usual, pushes the conspiracy theory that "Globally, temperatures have pretty much flatlined for well over a decade.", so climate science is wrong. What Geoff fails to tell you is that global temperatures have continued on their inexorable climb, by warming oceans and melting ice, amongst other things Geoff also avoids mentioning that trends in temperature are almost impossible to detect amidst the 'noise' of normal climatic variations, which is why such ternds are taken over periods of thirty or more years. Saying there has been little detectable trend in surface air temperatures over the last decade is the same as saying there is little detectable trend in temperatures since last Tuesday: even if true, the statement is meaningless to the discussion.
      Geoff has had this pointed out frequently. What do you call someone who refuses to acknowledge the truth?

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  10. Mustafa Epstein

    Political Scientist

    Following the release of the BoM's research, I conducted my own. I was surprised that they chose a period 1961 to 1990 as their benchmark. Surely if one has figures dating back to federation, you'd chose 1901 to 2012 as the benchmark, unless that would disprove the your "facts".

    Anyway - here's the BoM's own figures for station number 48031 at Collarenbri.

    * 10 out of the 12 months highest average monthly mean maximum temperatures occured prior to 1960.

    * The actual average decrease in highest average monthly mean maximum temperatures and 2012 is 4.2 degrees celcius.

    * Put another way, average maximum temperatures at Collarenbri prove that since 1901, they have decreased by 15.2%

    I further note that the BoM's website gives no reason why 1961-1990 was chosen.

    I am quite willing to have my figures peer reviewed, unlike the BoM who provide no links to the data used in their pres release or at their website.

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    1. Phillip Johnstone

      Research Fellow at Science-Policy Interface

      In reply to Mustafa Epstein

      Mustafa

      can you please explain the mathematics behind the "15.2%" figure? My understanding is that quoting percentages of arbitrary scales, such as temperature, are meaningless.

      You would probably get a larger percentage if you used Fahrenheit rather than Celsius. Or, if you want to decrease the percentage, switch to Kelvin.

      Can you also provide some rationale for selecting Collarenbri as the indicator of global trends?

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    2. Mustafa Epstein

      Political Scientist

      In reply to Mike Hansen

      Exactly which stations did the BoM chose and why ??????

      And why wont they provide a link to their data ?????

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    3. Mustafa Epstein

      Political Scientist

      In reply to Mustafa Epstein

      I chose Collarenebri having lived there during a drought working for an Aboriginal corporation. It was bloody hot - yet the temperature during that period never went near previous records, let alone average mean maximums as recorded by the BoM.

      As to there being a World Meteorological Organisation standard, no doubt it was chosen for obvious reasons. When data is chosen, it should reflect all collected data, not just what someone or some body prefer.

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    4. Felix MacNeill

      Environmental Manager

      In reply to Mustafa Epstein

      Mustafa, either provide some solid evidence that the WMO has behaved irresponsibly or conspiratorially or take your nasty libels and shove them.

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    5. Felix MacNeill

      Environmental Manager

      In reply to Mustafa Epstein

      Ditto my comments about the WHO above. You have no right to libel professional scientists without a shred of credible evidence. Doing so merely exposes you as a bigot.

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    6. Mustafa Epstein

      Political Scientist

      In reply to James Whitmore

      That's like comparing apples with oranges. I prefer physical data compiled from he ground. I have yet to hear the BoM issing a press release to the MSM using satellite data.

      The simple fact is the BoM chose to use data, knowing that the premise that temperatures have increased, when in fact the data they hold, proves otherwise.

      I can hold my own with the BoM over their cherry-picked data.

      My data: http://t.co/QextNPijHF which was posted online by a mate.

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    7. Mustafa Epstein

      Political Scientist

      In reply to Felix MacNeill

      They use numerous periods, just ike the BoM.

      They choose which figures help in justifying their desired result.

      I challenge the BoM to use its own figures from 1901 to 1930 and see what result they get.

      It will be the same as Collarenebri even though CO2 has increased by 50%

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  11. Chris Harries

    logged in via Facebook

    A quick read of the headline of this article and I immediately thought: "Why create a headline that just eggs on the contrary argument... unless the aim of the authors was to re-kindle the endless war on whether or not AGW is real or not?"

    A more fruitful analysis would have extrapolated 2013 weather conditions into the next 20 years, giving a sense of what our summers will be like in 2033, when our kids become adults. Concluding that anthropogenic global warming is real almost calls to attention that there is scientific doubt when we should be well and truly beyond that inane period of fruitless discussion.

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    1. Mustafa Epstein

      Political Scientist

      In reply to Chris Harries

      I believe the earth is warming - but very very slowly. I also believe that scientists ignore other causes of said warming eg volcanoes including uderwater ones which they ignore in their ocean acidity. The amount of CO2 production they ignore outside that caused by humans is a scientific farce. That is why "the consensus" is ridiculed today !!!!!!

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    2. Account Deleted

      logged in via email @drdrb.net

      In reply to Mustafa Epstein

      Mustafa, the amount of CO2 produced by undersea volcanoes is less than 1% of that emitted by humans, and most of that is sequestered within the cooled larva anyway. http://www.skepticalscience.com/print.php?r=50

      You are not looking at the scientific literature, and it shows.

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    3. Mike Swinbourne

      logged in via Facebook

      In reply to Mustafa Epstein

      ".....I believe the earth is warming - but very very slowly. I also believe that scientists ignore other causes of said warming eg volcanoes including uderwater ones which they ignore in their ocean acidity....."

      Beliefs are what you have when you have no evidence for your view.

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    4. Mustafa Epstein

      Political Scientist

      In reply to Account Deleted

      Please direct me to the link in the IPCC 5th Assessment Report that shows this - after all - 97% of climate scientists treat this as the Holy Koran/Bible/Torah.

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    5. Mustafa Epstein

      Political Scientist

      In reply to Mike Swinbourne

      OK - I KNOW that the IPCC 5th Assessment Report shows no statistical increase in world temperaturs for the last 17 years and can't offer an explanation for same.

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    6. Chris O'Neill

      Retired Way Before 70

      In reply to Mustafa Epstein

      So in your religion, most of the atmospheric CO2 rise in the last 200 years is caused by undersea volcanoes even though there is a faster CO2 rise in the atmosphere than in the ocean and humans have released more CO2 from fossil fuel burning than the rise in the atmosphere.

      At least you let us know what religion is all about, i.e. belief that conflicts with evidence.

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    7. Account Deleted

      logged in via email @drdrb.net

      In reply to Mustafa Epstein

      To quote the 5th assessment report:

      WGI, 8.4.2 Volcanic Radiative Forcing

      "Global annually-averaged emissions of CO2 from volcanic
      eruptions since 1750 have been at least 100 times smaller than anthropogenic emissions, and inconsequential
      for climate on millennial and shorter time scales (Gerlach, 2011)."

      Next time try googling it for yourself.

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  12. Evelyn Haskins

    retired

    What I have not found out is just what measurements have been taken to determine the "hottest".

    Surely there are more readings now of local temperatires than there were in 1913?

    As well local conditions WILL vary as we arrogant human beings build ever enlarging cities, change the topographies and drainage courses, cut down forests.

    Or in otherwords I do NT think we have any way of accrutely determining whether or not *Australia's* climate is getting hotter so much as that our cities are getting hotter. Ot since we buldized thse sand dunes and built high rise Hoiday Towers on them, the average temperatire at xyz site is higher that it was N years ago when we firtst put that gauge there!

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    1. Felix MacNeill

      Environmental Manager

      In reply to Evelyn Haskins

      Evelyn, do you not realise that scientists are able to adjust for issues like local heat islands and changing equipment and numbers of measuring stations. The fact that they don't provide detailed explanations of these processes and standard methods in this article is because (a) it is well known and understood in the scientific community and (b) you or I probably wouldn't understand it anyway.

      However, taking a little time to read the BoM website and other basic literature can explain these things reasonably well.

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    2. Doug Hutcheson

      Poet

      In reply to Evelyn Haskins

      Evelyn, I think your question is well answered by the Berkely Earth Surface Temperature project, now known as Berkley Earth, which was funded by fossil fuel interests in an attempt to prove exactly what you are saying, but ended up proving that Global Warming is actually happening and the temperature records are reliable.
      http://www.berkeleyearth.org/

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    3. Evelyn Haskins

      retired

      In reply to Felix MacNeill

      'Scientist' is used by non-scientist in a weird way,\
      'Scientists' are still debating the effect of human activity on Global weather.

      Some scientists, such as Mammalian Palaentologists, are outspoken about the inevitable dooming of the planet due to Human activity causing gross climatic change. Other scientists are more moderated/informed in their views.

      As I see it the concern is that human activity is causing change that is likely to doom humans -- along with our commensals. The planet…

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    4. Mark Pollock

      Analyst

      In reply to Felix MacNeill

      I don't think the BOM provide any explanations for the adjustment s they make or when they were made. They should though.

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  13. Andrew Gilmour

    logged in via Facebook

    THis is an example of cherry picking article.

    The authors can go now to the US to the area with -50 degrees Celcius and then realise that the hottest in one spot doe snot mean anything without looking at some other spots. In some areas of the US people are freezing now like never before.

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    1. David Semmens

      logged in via Twitter

      In reply to Andrew Gilmour

      An area smaller than the whole of Australia has very cold, but not their coldest weather over a few days. And you accuse the authors of cherry-picking when they write about temperature averaged over the entire continent for an entire year and how it compares to temperature records dating back to 1910...

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    2. Andrew Gilmour

      logged in via Facebook

      In reply to David Semmens

      The hottest year for the near history means nothing as a year against hundreds of years is nothing. It is comparable to the coolest year in the middle of the US.
      Also, in Melbourne I do not see the hottest year for several years already as there is no actual summer since about 2009 or so. Can I make a conclusion about the coolest years in Mel and then extrapolate that? No in a similar manner how no conclusions can be made that Australia is warming based on one year even in case this one is the hottest.
      Our Bureau of Meteorology would better try to predict weather with the accuracy of 50% rather than writing articles with no meaning.

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    3. Felix MacNeill

      Environmental Manager

      In reply to Andrew Gilmour

      No Andrew, it's an example of somebody picking a focused topic and writing about it. That topic was recent heat extremes in Australia and their likely causes.

      They also didn't talk about temperatures or any other kind of weather in any of the other 195 odd other nations on earth. Nor did you. So, if 1/195 is cherry picking, how is 2/195 not?

      Nor did they (nor any other climate scientist) claim that climate change only meant warming - there is a vast body of quality research indicating that…

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    4. David Semmens

      logged in via Twitter

      In reply to Andrew Gilmour

      1) It's not the coolest year in the middle of the US.

      2) The authors don't extrapolate a warming trend from a single year. Look at their first graph, a little over 100 years of data in there.

      3) The authors aren't from the BoM.

      4) Are you perhaps commenting on the wrong article? BoM climatologists wrote an article about 2013 here: https://theconversation.com/2013-was-australias-hottest-year-warm-for-much-of-the-world-21670

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    5. Doug Hutcheson

      Poet

      In reply to Andrew Gilmour

      Andrew, what I am sure you meant to say was "the hottest, or coldest, in one spot doe snot mean anything without looking at all other spots". That's why measurements are taken of the whole globe, not just a few cherry-picked examples.

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    6. Andrew Gilmour

      logged in via Facebook

      In reply to Doug Hutcheson

      That is why Doug talking about the hottest year in Australia does not make sence at all.

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    7. Andrew Gilmour

      logged in via Facebook

      In reply to David Semmens

      David,
      1. it is the coolest -50 degrees Celcius in the US now and 40 y.o. people living there never experienced this cold before. So what? can we write an article saying that the coolest temperature in the US compensates the hottest in AU? What is the goal of writing such articles about the coolest or warmest temperatures at all?
      Such articiles are directed to uneducated public reading these articles and ten screaming about GW and our government doing nothing.
      2. 100 years of history is nothing in comparison with the history of the planet.
      3. They are not from BOM, they are academics. Even worse...
      4. I am commenting on the right article, thanks.

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    8. Andrew Gilmour

      logged in via Facebook

      In reply to Felix MacNeill

      A focused topic:

      Now we face the coldest year in the US and T reaches -50 degrees Celcius. Mature people never experienced such temperatures before in their lives. THis is totally opposite to Australia.

      There is a perfect balance in nature. Somewhere heat is growing, sonewhere cold is going ahead.

      There is no need to be a climate science professor to write such articles.

      P.S. One or two in 195 is no stats at all. A thousand of credible measurements (years) among millions is much better. Until then BoM or Climate professors should just collect stats.

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    9. Chris Harries

      logged in via Facebook

      In reply to Andrew Gilmour

      Those health officials who looked at the relationship between smoking and cancer should have just collected stats instead of scaring the smoking public with alarmist health warnings! After all, some people who smoked all their lives didn't get cancer and lived to 90, proving beyond doubt that the purported cancer link was a hoax.

      (The above is, of course, tongue-in-cheek. )

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    10. Chris O'Neill

      Retired Way Before 70

      In reply to Andrew Gilmour

      "THis is an example of cherry picking article."

      Sure. It picks the whole of Australia for a whole year.

      "The authors can go now to the US"

      Your cherry picking is far worse. You're picking an event that lasts a few days at the most.

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    11. Andrew Gilmour

      logged in via Facebook

      In reply to Chris O'Neill

      Chris, my example is a typical cherry picking in absolutely similar manner how the authors have done that in this article. No difference whatsoever.

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    12. David Semmens

      logged in via Twitter

      In reply to Andrew Gilmour

      No, we definitely can't say that a cold temperature measured at one location on a single winter's day might compensate for the average temperature measured at many locations across an entire continent for an entire year. It would make much more sense to compare temperatures measured across many locations on the same continent over many years, which is what the article does.

      This article is not just about Australia's hottest year on record. It's about how we cannot attribute recent higher than average temperatures to natural variation alone. The influence of anthropogenic greenhouse gas emissions must be included to explain them. Temperatures in the past, even millions of years ago, can be attributed to particular causes. Recent temperatures can also be attributed to causes. Some of the causes are natural and some are man-made. If recent temperatures were only caused by natural influences, they should be cooler.

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    13. Chris O'Neill

      Retired Way Before 70

      In reply to Andrew Gilmour

      No it is not absolutely similar, unless you think a few days is the same as a whole year. Or are you saying there is no difference whatsoever between a few days and a whole year?

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    14. Chris O'Neill

      Retired Way Before 70

      In reply to Andrew Gilmour

      "Now we face the coldest year in the US"

      This guy is clairvoyant. He can see the whole of 2014.

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  14. David Semmens

    logged in via Twitter

    Eyeballing the first graph it would seem that if the full models have a failing it is that they under-predict temperatures on average after about 1980. Do the authors have a sense if that is the case and what factors might be contributing to the discrepancy?

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  15. Geoffrey Sherrington

    Surveyor

    This article by well-known activists has errors from the title and the first sentence.
    "Australia’s hottest year was no freak event: humans caused it ". Wrong. We do not, can not know if humans caused all or part of it.
    First sentence "... since records began in 1910". The BoM has public records from Australia back to Melbourne 1855. By 1910 there were about 80 operating weather stations - now in the BoM public documents.
    Particularly interesting are the years in the late 1890s that are inconveniently…

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    1. John Doyle

      architect

      In reply to Geoffrey Sherrington

      Interesting to read about it.
      The Berkeley Earth data mentioned above doesn't show up anything unusual regarding this heat wave even inland like at Deniliquin, Ivanhoe and Broken Hill. It seems to have been just a one off event.
      Maybe the readings were discounted in the official data?
      Certainly Berkeley Earth show a rise in temperature since about 1860. Closer to the poles the rise is in the order of 3 degrees,closer to the equator the rise is about 1 degree since then.

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    2. Geoffrey Sherrington

      Surveyor

      In reply to John Doyle

      John.
      I don't know enough about BEST. I spent days cleaning up their early version of Australia then packed it off to one of their team with a list of cautions. I don't quite know what they did to it because I stopped reading their reporting soon after it became apparent that they were making mistakes against which I had cautioned.
      So no, I'm not really familiar with BEST.
      I do suspect, though, that the 1896 heat wave was rather much as I stated because a team of us researched it and cross checked. It was likely a global event when you account for reports from other countries. But then the Federation drought was fairly severe too, but it's not described as breaking records since recording began.
      Artificial temperature adjustments do not kill birds like natural causes do.

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

      Farmer

      In reply to Geoffrey Sherrington

      Geoff,

      Rather intrigued by your "cleaning up" and the cautions suggested... Any of this been published anywhere? If not could you give me an idea of what this cleansing involved?

      Also be most interested in the research you and th team did on 1896 and the cross checking involved. Was this published anywhere and what sort of cross checking was involved?

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    4. John Doyle

      architect

      In reply to Geoffrey Sherrington

      It should then be in the BoM data surely? 54 at Berlino would be the record. I see that the Libya world record temp of 136 degrees f has lost its record to a slightly lower one in Death Valley, from1922 I think.
      I was just enquiring If you or someone knew how come we have news reports, which you quote, but not official records.
      Is your research available on the web?
      Have you read the ideas of John Hamaker? He posits glacial periods are caused by vegetation growth and loss. An interesting idea.
      For him global warming from CO2 leads to an ice age.

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  16. Dianna Arthur

    Environmentalist

    Thanks for concise comprehensive article. Now to get our leaders to read, understand and take action.

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  17. John Phillip
    John Phillip is a Friend of The Conversation.

    Grumpy Old Man

    Sophie, you've made the following assertion :"Averaged across all of Australia, the temperature for 2013 was 1.2C above the 1961-1990 average, and well above the previous record hot year of 2005 of 1.03C above average."
    I'd be interested in knowing if the same stations were used in making the temperature record for the two compared periods along with any equipment or methodology changes. What would be the effects on the record if different and/or additional stations were used?

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    1. Geoffrey Sherrington

      Surveyor

      In reply to Sophie Lewis

      Sophie,
      We have been unable to replicate ACORN-Sat temperatures leading to national averages.
      Are you saying that BoM assured you that the same stations were used for the 1961-90 reference period, the temperature data for years 2005 and 2013?
      Seems to us that 3 West Australian Acorn stations that were in the set in 2005 are not in the set in 2013.
      Would you like to reconsider your response if you have not checked and found by your inspection that the stations indeed remained the same?

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  18. Geoffrey Sherrington

    Surveyor

    Houston, we have a problem with our Establishment science, settled though it is. So, we build new instruments to confirm how settled it is. Here's a comparison for Australian land (with some cells edging over the sea) from satellite microwaves translated by University of Alabama; and its comparison with the BoM and its translation of land temperature. Both are expressed in a customary but horrible way, as annual anomalies which vary from some stated prior common reference period. Left axis is Deg…

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

    Farmer

    Top article ... nice and succinct.

    I was off reading George Lakoff ... an excellent way to cheer oneself up for the New Year.

    He makes a useful and important argument in favour of the concept of "systemic causation" ... namely that while direct causation - say a punch on the snout leading to a bloody nose - is easy to identify, the more complex interactions found in large scale nature and complex systems (like human society) - usually an interplay of multiple interactive forces - are no less causal, despite being more complex and less immediately direct.

    It is an interesting concept and a useful bit of lingustics... a neat piece of precise meaning.

    The article in question is here: http://www.huffingtonpost.com/george-lakoff/sandy-climate-change_b_2042871.html

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    1. Jane Middlemist

      citizen

      In reply to Peter Ormonde

      Thanks Peter, for that link. We really need to talk a lot more about systemic causation. Makes more sense than interminable arguments about whether climate change is real.
      Seems that train left the station a while ago :-)

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  20. George Valakirev

    logged in via email @gmail.com

    I can see David Karoly's retraction from the Journal of Climate has not been cleared up:

    http://newsroom.melbourne.edu/studio/ep-149

    This dodgy hockey stick evidence would not have been found without the hard work of someone who after questing the conclusion, put time into investigating it when others, including reviewers (read: climate scientists) accepted it with blind faith. How can we trust any other so-called evidence you offer David Karoly?

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  21. Jim Inglis

    retired

    So it's us humans wot caused it?

    But Sophie and David don't say how. Was it:

    Human land use change?

    Humans putting the thermometers mostly where the greatest LUC is?

    Humans putting thermometers in hot places where they weren't before?

    Humans removing thermometers from cool places where they were before?

    Humans removing old hot records?

    Humans generally cooking the books?

    There are probably other things that humans do [that presently elude me] but that is probably enough to make the "fraction of attributable risk" beyond question.

    In fact the risk is so attributable from the above that other causes [that presently elude me] could even have the reverse effect but still we would have a considerable net warming.

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

      Farmer

      In reply to Jim Inglis

      Yes indeedy Jim - these scientists are so dumb aren't they... any bloke with the time, a calculator and an interweb connection can just run rings around them ... don;t even need any training or experience at all ... just common sense and intuitive understanding of everything around us.

      Or is there a method in their obvious stupidity? What are they planning Jim at their secret symposiums and conferences? World domination? Global economic destruction? The possibilities are endless... personally I suspect the Secret Plan is to impose a junta of TV weather dudes to rule us all... all teeth and haircuts.

      Be afraid Jim be very afraid... and be amazingly arrogant at the same time...

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  22. Comment removed by moderator.