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Uncertainty no excuse for procrastinating on climate change

Today we released research which reduces the range of uncertainty in future global warming. It does not alter the fact we will never be certain about how, exactly, the climate will change. We always have…

We’ll never know how much the globe will warm, but we have a pretty good idea: what are we waiting for? Luis Ramirez

Today we released research which reduces the range of uncertainty in future global warming. It does not alter the fact we will never be certain about how, exactly, the climate will change.

We always have to make decisions when there are uncertainties about the future: whether to take an umbrella when we go outside, how much to spend on insurance. International action on climate change is just one more decision that has to be made in an environment of uncertainty.

The most recent assessment of climate change made by the Intergovernmental Panel on Climate Change in 2007 looked at what is known with high confidence about climate change, as well as uncertainties. It included projections of future global warming to the end of this century based on simulations from a group of complex climate models.

These models included a range of uncertainties, coming from natural variability of the climate and the representation of important processes in the models. But the models did not consider uncertainty from interactions with the carbon cycle - the way carbon is absorbed and released by oceans, plant life and soil. In order to allow for these uncertainties, the likely range of temperature change was expanded.

Our recent study has re-visited these results and tested an approach to reduce the range of uncertainty for future global warming. We wanted to calibrate the key climate and carbon cycle parameters in a simple climate model using historical data as a basis for future projections. We used observations of atmospheric carbon dioxide concentrations for the last 50 years to constrain the representation of the carbon cycle in the model. We also took the more common approach of using global atmospheric and ocean temperature variations to constrain the response of the climate system.

This led to a narrower range of projected temperature changes for a given set of greenhouse gas emissions. As a consequence, we have higher confidence in the projections. In other words, using both climate and carbon dioxide observations reduces the uncertainties in projections of global warming.

Figure 1. Global-mean temperature change for a business-as-usual emission scenario, relative to pre-industrial. Black line: median, shaded regions 67% (dark), 90% (medium) and 95% (light) confidence intervals. The sidebars are uncertainty ranges based on the IPCC likely range and best estimate (grey column) for 2090-2099 and our corresponding results (purple column) from the simple climate model (MAGICC); the black bars are the respective best estimates (modified from Nature Climate Change paper). Bodman & Karoly

We found that uncertainties in the carbon cycle are the second-largest contributor to the overall range of uncertainty in future global warming. The main contributor is climate sensitivity, a measure of how the climate responds to increases in greenhouse-gas concentrations.

Climate sensitivity has been discussed recently on The Conversation. A recent study by Alexander Otto of Oxford University and colleagues, published in the journal Nature Geoscience, also considered future global warming in the context of observations of global mean temperature change over the last decade.

Unlike that study, our results do not show lower climate sensitivity or lower mean projected global warming. Our study uses the same observed global atmospheric and ocean temperature data. But we also used observed carbon dioxide data and represented important additional processes in our simplified climate model, particularly the carbon cycle on the land and in the ocean and uncertainties in the climate forcing due to aerosols.

In our study, the reductions in uncertainty came from using the observations, the relationships between them and how these affect the parameters in the simple climate model. We found 63% of the uncertainty in projected warming was due to single sources, such as climate sensitivity, the carbon cycle components and the cooling effect of aerosols, while 37% of uncertainty came from the combination of these sources.

Once we reduced the uncertainty we found there is an increased risk of exceeding a lower temperature change threshold, but a reduced chance of exceeding a high threshold. That is, for business-as-usual emissions of greenhouse gases, exceeding 6°C global warming by 2100 is now unlikely, while exceeding 2°C is virtually certain.

These results reconfirm the need for urgent and substantial reductions in greenhouse gas emissions if the world is to avoid exceeding the global warming target of 2°C. Keeping warming below 2°C is necessary to minimise dangerous climate change.

It is unlikely that uncertainties in projected warming will be reduced substantially. Indeed, if you allow for population growth, levels of economic activity, growth in demand for energy and the means of producing that energy, overall uncertainty increases. We just have to accept that we will have to manage the risks of global warming with the knowledge we have. We may not know exactly how much and by when average temperatures change, but we know they will. This is an experiment we probably don’t want to make with the only planet we have to live on.

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61 Comments sorted by

Comments on this article are now closed.

  1. Liam J

    logged in via email @gmail.com

    I fear science-as-usual will provide us with a perfect record of our demise. When will scientists put survival above their salaries and get political, by say a boycott of systemic deceit (certain media corporations) or a science strike (all sciences and allied technologies)?

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

      ag science research

      In reply to Liam J

      You can support the Union of Concerned Scientists http://www.ucsusa.org/ who do try to counter and expose some of the media corporations and vested interests in the US and elsewhere

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    2. Liam J

      logged in via email @gmail.com

      In reply to Peter Innes

      The UCS do good work, as does Medical Assoc for Prevention of War and a few others. But they are minority groups within their well remunerated professions, and obviously not succeeding. Science/most scientists & technicians have been bought.

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  2. Sean Lamb

    Science Denier

    Mark the 27th May 2013 in your calender, ladies and gentlemen. Because today is the day when climate change officially changed from being a science to being a religion. A science potentially is open to challenge by new data, a religious belief is impervious to any evidence.

    Through a sleight of hand Professor Karoly and colleagues and dramatically shifted the goal posts by saying they expect absolutely no warming - none whatsoever - until 2030. After which temperatures will - for mysterious…

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    1. Donald Runcie

      retired

      In reply to Sean Lamb

      Perhaps when cinsidering computer projections, we all should take note of Donald Rumsfield's famous aphorism- "we know what we know; ws know what we don't know; but we don't know what we don't know! "

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    2. Sean Lamb

      Science Denier

      In reply to Donald Runcie

      Yes, I was thinking of using that on the vaccine thread - but didn't get round to it.

      I wonder how Karoly's projection would look if he had to extend it backwards 60 years? A curious sigmoid shape, actually a double sigmoid as it flattens out again towards 2100 - a hockey stick as drawn by Pablo Picasso (my imagination has failed trying to come up with a suitable sporting accessory sobriquet). Neither rhyme or reason, but driven solely by political expediency.

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    3. Michael Marriott

      logged in via Twitter

      In reply to Sean Lamb

      Sean, you've outlined a conspiracy theory - that scientists change their minds to keep their jobs and keep climate science on the front pages of newspapers.

      There are many, many good reasons to dismiss conspiracy thinking.

      If I may suggest, consider how improbable your argument is:

      http://watchingthedeniers.wordpress.com/2012/07/17/the-insiders-if-climate-change-was-a-conspiracy-where-are-whistleblowers/

      "…No secret – no matter how closely guarded its holders believe it to be – is…

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    4. Mike Hansen

      Mr.

      In reply to Sean Lamb

      Mark the 27th May in your calendar and the 28th and the 29th etc etc

      Because on those days science denier Sean Lamb will be found trolling The Conversation lying about climate science articles and climate scientists to feed his expensive Dunning Kruger habit.

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    5. Geoffrey Henley

      Research Associate

      In reply to Michael Marriott

      "The work of 97% of those actively researching climate change supports the view human activities are changing the climate."

      The 97% figure is a myth. The studies (Doran, anderegg, Oreskes) which supposedly are used to support this figure are all methodologically flawed.

      Doran: The 97% figure is derived from the voluntary responses of a mere 77 earth scientists who had published something to do with climate to a vague and ambiguous question that even some prominent sceptics said they would…

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    6. Laurie Strachan

      Writer/photgrapher

      In reply to Donald Runcie

      Actually Donald, your second and third statements are simply contradictory. What your namesake said was:

      There are known knowns; there are things we know that we know.
      There are known unknowns; that is to say, there are things that we now know we don't know.
      But there are also unknown unknowns – there are things we do not know we don’t know.

      In any case why reply to someone who calls himself a science denier while using electronic communications. Who does he think invented computers and the Internet, the Spanish Inquisition?

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    7. Sean Lamb

      Science Denier

      In reply to Felix MacNeill

      Oh Felix, if I have seen further than you it is by standing on the shoulders of giants. Speaking of which I took the liberty of lining up Karoly's recent publication with the one that appears to have disappeared down the memory hole:
      http://img507.imageshack.us/img507/3047/tempes.png
      A thing of beauty is a joy for ever:
      Its loveliness increases; it will never
      Pass into nothingness; but still will keep
      A bower quiet for us, and a sleep
      Full of sweet dreams, and health, and quiet breathing.

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    8. Sean Lamb

      Science Denier

      In reply to Mike Hansen

      "Because on those days science denier Sean Lamb will be found trolling The Conversation lying about climate science articles and climate scientists to feed his expensive Dunning Kruger habit."

      Now, now, Mr Hansen. Won't you join with me in reciting the Climate Scientist's Creed? Make me warmer, dear God, just not yet - or during the next 20 years for that matter.

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    9. Felix MacNeill

      Environmental Manager

      In reply to Sean Lamb

      Unlike you, I don't have that much time to waste - and bad verse doesn't improve bad reasoning.

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    10. Geoffrey Henley

      Research Associate

      In reply to Michael Marriott

      "Hence the 66% of papers are silent because it is taken as a given humanity has changed the climate."

      Most sceptics would not disgree that "humanity has changed the climate." The question is by how much. The arguments by Cook and others is that human activities will cause the planet to heat dangerously, yet his latest study does not provide much support for this.

      Of the 12,000 or so papers included in this study, the authors of ONLY 65 of these papers endorse a statement that humans are…

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    11. John Bromhead

      logged in via email @netspeed.com.au

      In reply to Felix MacNeill

      John Keats poem ends,

      And now at once, adventuresome, I send
      My herald thought into a wilderness:
      There let its trumpet blow, and quickly dress
      My uncertain path with green, that I may speed
      Easily onward, thorough flowers and weed.

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    12. Chris O'Neill

      Victim of Tony Abbotts Great Big New Tax

      In reply to Sean Lamb

      Sean Lamb, Science Denier, Global Warming Denier and Allround Clown:

      "they expect absolutely no warming until 2030"

      And where, pray tell, do they say that?

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    13. Donald Runcie

      retired

      In reply to Greg North

      Greg, to the best of my knowledge, none of my antecedents passed through the US.

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    14. Michael Marriott

      logged in via Twitter

      In reply to Geoffrey Henley

      Geoffrey, I know it is troubling to find out there is a consensus. I goes against every belief and value you have.

      Cook et.al is a lit review - it is about the scientific consensus: stunning to find, but yes there is 97% consensus humanity has changed the planet.

      Actually, it is worth repeating that point: there is 97% consensus humanity has changed the planet

      The Cook et.al paper:

      - makes no claims about climate sensitivity
      - makes no claims about the degree of warming
      - makes no…

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    15. Felix MacNeill

      Environmental Manager

      In reply to John Bromhead

      I don't like Keats. I studies literature at university, and I just don't like Keats.

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  3. John Newlands

    tree changer

    Joe Public believes in climate change if he sees it looking out the window. Otherwise nnyah. Unless we get decent winter and spring rain over southern Australia both wheat yields and hydro will be down on last year. We should have a clearer idea of that by the election in mid September. Then we'll have a choice of a government that seems serious about climate against one that seems to mock the idea. Both are inadequate.

    After we have decided that climate change is not such a problem Mother Nature will probably send more heatwaves, floods and firestorms of unprecedented severity. A case of getting what you don't pay for. The good thing is I think even good quality coal will be getting scarcer by 2030 or so if we can hang on another decade or two.

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    1. Greg North

      Retired Engineer

      In reply to John Newlands

      I think you're talking more of weather variations John and even the records of the past century are probably nothing compared to how the weather has varied for the many prior.

      Meanwhile, still plenty of coal about to be burnt and we are just shipping it abroad whilst governments here sit on their hands and just let Joe Public pay more and more for a less reliable supply.

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    2. Felix MacNeill

      Environmental Manager

      In reply to Greg North

      Yes, Greg, he was talking about weather variations (I think he understood that fact) if you actually bother to read his coments with a little care, you'd realise he ewas talking about how people's perceptions are mainly derived from short-term observations of the weather.

      That's 'perceptions' rather than 'facts'. There is a difference. You should look it up some time.

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  4. Mike Hansen

    Mr.

    Last week the climate crank web sites were trumpeting the Otto et al study which found a lower transient climate response (time was suspended briefly as AGW and models were suddenly OK given they had a result they liked).

    This week a new sensitivity study has been released in the journal Climate Dynamics which finds a most likely TCR of 2.0 C. Do not expect this study to be mentioned by the "skeptics" - their "skepticism" is very selective.

    "Probabilistic projections of transient climate change"
    "Our technique provides a rigorous and formal method of combining several lines of evidence used in the previous IPCC expert assessment of the Transient Climate Response. The 10th, 50th and 90th percentiles of our observationally constrained PDF for the Transient Climate Response are 1.6, 2.0 and 2.4 °C respectively, compared with the 10–90 % range of 1.0–3.0 °C assessed by the IPCC."
    http://link.springer.com/article/10.1007%2Fs00382-012-1647-y

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    1. Sean Lamb

      Science Denier

      In reply to Mike Hansen

      Both studies were bad. Otto's study was bad in a fascinating way. This one is just bad.
      Why should I waste time on it?

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    2. Greg North

      Retired Engineer

      In reply to Mike Hansen

      I'm not sure Mike and that's perhaps a measure of uncertainty as to whether I should take to heart more the phrase sensitivity study or a Probalistic projection.

      I just wish I had such a grasp of lingo to snowball my chemistry teachers to have got better marks when studying.

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    3. Mike Hansen

      Mr.

      In reply to Sean Lamb

      You are a science denier Sean. I do not expect you to spend any time on it.

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  5. Peter Lang

    Retired geologist and engineer

    >"Uncertainty no excuse for procrastinating on climate change"

    The reason there is little real progress on mitigating global GHG emissions, and no real progress in 20 years of international climate negotiations, is that the 'Progressives' have taken entirely thew wrong approach from the start. The rationalists have been saying from the start that if we try to take an economically irrational approach it will not succeed. Yet, still the 'Progressives' continue to advocate their irrational policies; such as pricking carbon and mandating high cost near useless renewable energy.

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    1. Peter Lang

      Retired geologist and engineer

      In reply to Peter Lang

      As Miles Allen said:

      >"Since Kyoto, world emissions haven’t fallen – they’ve risen by 40 per cent. And these vast jamborees – some involving more than 10,000 people – haven’t even started to discuss how we are going to limit the total amount of carbon we dump in the atmosphere, which is what we actually need to do to avoid dangerous climate change."
      http://www.dailymail.co.uk/news/article-2331057/Why-I-think-wasting-billions-global-warming-British-climate-scientist.html

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    2. Michael Marriott

      logged in via Twitter

      In reply to Peter Lang

      Peter, I'm not sure what you mean by "progressives" - do you mean the science community?

      You're confusing attribution with mitigation.

      You don't like what mitigation suggests – cutting back on fossil fuels, and fear it may impact your lifestyle. Many supporters of the free market don't like the thought the market has failed or we may have to - heaven forbid – introduce regulations that curb atmosphere pollution.

      Ergo for science denies: Climate science bad!

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  6. Greg North

    Retired Engineer

    There's certainly a fair measure of uncertainties or reference there to in this article, to a Cricket team extent and a fair bit of uncertainty there too with probabilistic projections of transient performances when it comes to climatic catches, catches win matches they do say.

    But really, here we have a study regurgitating studies and is that what climate change authoritarism has come down to?, a report on many uncertaintities you could say and that can only lead to confusion and further uncertainty…

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    1. Michael Marriott

      logged in via Twitter

      In reply to Greg North
  7. Mark Pollock

    Analyst

    At least the authors have the good grace to acknowledge that the global temperature has not been rising for the last 13 or so years (from their graph) and probably won't rise in the immediate future.

    A chink of daylight is getting in between the shutters.

    Also, they should be commended for acknowledging that "the science" is anything but settled. This might encourage a more open and honest and dare I hope, civil, discussion on the issue. Perhaps some of the more zealous protagonist might pause for a moment and consider what it is, exactly, that the deniers are denying?

    Their closing statement "We may not know exactly how much and by when average temperatures change, but we know they will" is two thirds of the way to being scientific. Well done.

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    1. Mike Hansen

      Mr.

      In reply to Mark Pollock

      Mark - have you ever read any climate science other than what is found on climate science denier blogs?

      Far be it from me to question your trusty eyecrometer (or have you borrowed Sean Lamb's?) but the graph and the science in this article is pretty much what you will find in the IPCC reports.

      Your strawman argument - that this article refers to uncertainty but previous climate science does not - certainly suggests that you are getting your climate science second hand.

      In fact the whole point of this article was that the research led to a REDUCTION in uncertainties in global warming projections compared to the IPCC.

      The following sentence is the giveaway. (And the fact that MAGICC projections are contained within the IPCC projections.)

      "As a consequence, we have higher confidence in the projections. In other words, using both climate and carbon dioxide observations reduces the uncertainties in projections of global warming."

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    2. Felix MacNeill

      Environmental Manager

      In reply to Mark Pollock

      Mark, you need to distinguish between 'the science' on the one hand (which is settled) and' the fine details of precisely predicting the behaviour of a large, complex system' which of course, are still being refined - not least by this report.

      Nothing here back pedals or changes the fundamentals. Only fools ever believed that the whole of climate change amounted to surface temperatures, or that they would procedede in a smooth, linear fashion. This may constitute the largest straw man yet constructed by the human race.

      The closing statement is wholly scientific. You have advanced no evidence-based counter-arguments as you have none. therefore you are not in a very strong position to critique other people's actual scientific work.

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    3. Donald Runcie

      retired

      In reply to Mark Pollock

      Mark, I think that you have defined the problem with many discussions of climate problems- "what it is, exactly, that deniers are denying?" The English language is capable of exquisite precision, which is not always being used. I would think that many "deniers" are denying the concept of "anthropogenic global warming." If Milancovich can be believed, the present global warming which commenced after the end of the previous ice age about ten thousand years ago (give or take a week or so), is part of the normal climate cycle. If the phrase "anthropogenic aggravation of global warming" was used, there would fewer "deniers". This is not splitting hairs, it is using English as it should be used.

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    4. Mike Hansen

      Mr.

      In reply to Donald Runcie

      You have it completely back to front Donald

      If not for AGW, the world would be cooling.

      "Earth orbital (Milankovic) parameters have favored a cooling trend for the past several thousand years, which would be expected to start in the Northern Hemisphere. For example, Earth is now closest to the sun in January, which favors warm winters and cool summers in the Northern Hemisphere, thus favoring growth of glaciers and ice caps in the Northern Hemisphere"

      http://www.columbia.edu/~jeh1/mailings/2011/20110118_MilankovicPaper.pdf
      "Paleoclimate Implications for Human-Made Climate Change", James E. Hansen and Makiko Sato

      For those interested in the maths, there is a discussion here
      http://tamino.wordpress.com/2011/01/25/milankovitch-cycles/

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    5. Mark Pollock

      Analyst

      In reply to Donald Runcie

      Thanks Donald. It's not just the language that is capable of exquisite precision, science and its advocates should also pay attention to the details.

      I have no trouble with "climate change" - it changes all the time. I also have no problem with "anthropogenic climate change". Building huge cities on swamps, converting prairies into arable land, diverting rivers and building dams obviously will have some effect on the climate. I can even see how, theoretically, putting more CO2 into the atmosphere might have some effect.

      When I wonder about the quantity of the effect I somehow turn into a "denialist.

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    6. Mark Pollock

      Analyst

      In reply to Mike Hansen

      Mike, that's excellent. Less uncertainty is no doubt a very good thing. However, this does imply that previous projections were more uncertain. I would have said that these previous more uncertain projections were flaky, shaky, and completely unreliable, based, as they seemed to be, on unsupported correlations and short-term linear trend lines drawn over what was an obviously non-linear system. But that's just me.

      It's clear that we are not going to agree on the details but surely we can agree with the authors that "We may not know exactly how much and by when average temperatures" average temperatures will change?

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    7. Mark Pollock

      Analyst

      In reply to Felix MacNeill

      Felix, that's sort of my point. An awful lot of people do believe that climate change amounts to an increase in surface temperatures and that these increases proceed in a smooth linear fashion. Many of these people are passionately involved in green/climate advocacy. Smooth linear increases, especially based on the 1970-1997 trend keep the money rolling in.

      When Kevin talked about the "greatest moral challenge, etc, etc", he wasn't talking about the uncertainties - he was talking about a straight-line…

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    8. David Bentley

      logged in via LinkedIn

      In reply to Mark Pollock

      So, what do you suggest Mark?

      It seems fairly obvious to all but a few that there is a real issue here and whilst there is a level of uncertainty, it would seem rather unwise to assume that things will be all ok, and/or we should wait until we have full certainty to act.

      I think what most authors on this site seem to rightly argue is that it would be better to start doing something about it now and to continue to try to refine our understanding of the issue along the way.

      I don't think you could accuse any of the authors of articles on The Conversation of not being honest about the risks and the uncertainties here.

      There is no uncertainty that man is having an impact on the global climate....and it's not a positive one. Given that, let's stop arguing and start doing something about it shall we?

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    9. Donald Runcie

      retired

      In reply to Mike Hansen

      Miike, I am obviously not a climate scientist (or any other kind of scientist), but I read recently a paper which proposed that the Pleistocene-Holocene Transition was due to diversion of the Antarctic Circumpolar Current by the enlarging Antarctic icecap. This led to the current passing over part of the ocean floor which was very uneven. This caused the current to be agitated to the extent that much CO2 was released, leading to considerable postive feedback,
      Would you care to comment?.

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    10. Mike Hansen

      Mr.

      In reply to Mark Pollock

      "An awful lot of people do believe that climate change amounts to an increase in surface temperatures and that these increases proceed in a smooth linear fashion. Many of these people are passionately involved in green/climate advocacy. Smooth linear increases, especially based on the 1970-1997 trend keep the money rolling in."

      That is largely nonsense Mark. You keep making claims without providing any evidence.

      The "going down the up escalator" graph (linked below) is famous - precisely because…

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    11. George Takacs

      Physicist

      In reply to Donald Runcie

      Donald,

      I will comment. This mechanism is only plausible because CO2 is a gas which absorbs electromagnetic radiation in the mid-infrared. Levels of CO2 in the atmosphere can be influenced by by internal factors (the paper you referenced) or external factors (insolation).

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    12. Peter Anderson-Stewart
      Peter Anderson-Stewart is a Friend of The Conversation.

      Medical scientist

      In reply to Mark Pollock

      So, would you please tell us at what point will you cease to be "denialist"?

      Is it 0.05C, 0.5C. 5.0C per year, over ten years, one hundred years? Please, please, just let us know ...

      I never cease to be amazed at the responses from those that never seem to be able to produce a peer reviewed paper on anything from climate change to vaccination "big pharma" conspiracies to support their, well, how do I put this gently, florid beliefs.

      We are, by and large, an educated civilisation with, generally…

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    13. George Takacs

      Physicist

      In reply to Donald Runcie

      Donald,

      I am not sure what you are getting at. I don't see how a CO2 release 10,000 years ago is related to the post industrial revolution increase in CO2 levels.

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    14. Donald Runcie

      retired

      In reply to George Takacs

      George, I was thinking that the CO2 release causing the PHT would have continued for some time, producing the positive feedbacks that occured producing more atmospheric CO2 until the industrial revolution took over.

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    15. Felix MacNeill

      Environmental Manager

      In reply to Mark Pollock

      Firstly, all you have offered is a strawman argument that many people 'passionately involved in green/climate advocacy' believe in rapid/linear surface temperature increases. This is merely a contention and is completely unbacked by evidence and completely untestable, therefore it is correctly ignored. And your attempt to read Kevin Rudd's mind is equally useless (quite apart from being irrelevant anyway).

      I've never heard anyone who suggested that the system was complex and involved more than…

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    16. Mark Pollock

      Analyst

      In reply to David Bentley

      There may be no uncertainty about whether man is having an impact on the climate but there is a great deal of doubt about what that impact is. My guess is that it's "theoretical and too tiny to even notice. That doesn't mean it's not an impact. Given that, there's not much point in doing anything about it.

      There is certainly no point in wasting time or energy on things that will have no impact but are very expensive, like PVs and wind power and all the other cargo-cult nonsense.

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    17. Mark Pollock

      Analyst

      In reply to Mike Hansen

      I don't remember asking any questions about the paleo data in the Pliocene.

      That aside, no one to my knowledge says that the lack of global warming over the last 15-20 years or so (pick your climate product) means that "climate change" is not occurring, has stopped, never happened or whatever.

      They do say that the lack of recent warming was not predicted, forecast or projected in the models upon which the alarmists rely. Observation trumps theory in real science. There must be something wrong with the models.

      We can see in the article under discussion how the authors are slowly being "mugged by reality". Their graphed forecast has practically no change in global temperatures for thirty or so years. This is very different from model output published in the various IPCC reports.

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    18. Sean Lamb

      Science Denier

      In reply to Peter Anderson-Stewart

      "I never cease to be amazed at the responses from those that never seem to be able to produce a peer reviewed paper on anything from climate change to vaccination "big pharma" conspiracies to support their, well, how do I put this gently, florid beliefs."

      You are not the only one, Peter. I frequently marvel at myself.
      My fear is that people like Prof Karoly will make science denying look easy - I mean presenting one paper with a hockey stick and then the next paper with a long period moving to an exponential increase - its got "deny me" written all over it. In reality I spend years doing science denying study to get my skills honed to this razor-sharp level.
      I can tell you, it wasn't easy.

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  8. Phil Dolan

    Viticulturist

    Those that deny climate change are very similar to those that think they can find water by divining. If it is shown to be not true, they still believe it. They should be ignored because no sense can persuade them to think of anything but their welded on beliefs.

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  9. Ross Chester-Master

    logged in via Facebook

    We have and continue to develop better technology, than one way fossil fuels, for our lifestyle . We should go there because we can, as well as to slow the potential and/or actual defecation into our own nest. For my money, we should concentrate the scientific - technological effort in that direction. I truly hope no taxpayer money in Australia is spent on ports for fossil fools.

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