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Why the Republican Party's climate policy obstruction is indefensible

Posted on 5 July 2017 by dana1981

Two weeks ago, Senator Al Franken (D-MN) had an exchange with Trump’s Department of Energy Secretary Rick Perry about climate change. 

Perry’s responses perfectly summarized the Republican Party’s current position on the subject. The problem is that it’s an indefensible position.

Wrong on the science

The Republican position is based upon a rejection of established climate science. When confronted with the conclusion that global warming is 100% due to human activities, Perry responded, “I don’t believe that ... don’t buy it.” But of course it’s not a matter of belief – that’s what the scientific evidence indicates. There have been dozens of studies quantifying the various contributions to recent global warming. I summarized ten of them in the chart below (details here), and the answer is clear:

all of it

Human contribution to global surface warming over the past 50 to 65 years based on ten peer-reviewed studies (see for details). Illustration: Dana Nuccitelli and John Cook

That’s why the latest IPCC report likewise included a best estimate that humans are responsible for all of the global warming since 1950. During that time, solar activity has slightly declined, and there haven’t been any significant natural warming factors. Perry talked about “the warming and cooling of our ocean waters,” but the oceans have likewise steadily absorbed heat due to human-caused global warming.

On this issue there’s a 97% expert consensus whether you survey climate scientists or their public statements or their peer-reviewed literature. And the greater the climate science expertise of those surveyed, the higher the consensus.

Many Republican policymakers will now admit, like Perry, that humans have “some impact” on the climate. That simply represents an acceptance of 150-year-old science. They don’t deserve much credit for finally accepting science that was first established when John Quincy Adams was president.

Wrong on risk management

There’s a chance the less than 3% fringe minority of contrarian climate scientists are right. It’s a slim chance, given that their research doesn’t withstand scientific scrutiny, is full of errors, and their alternative explanations are all contradictory, but it’s not impossible.

But that’s like saying there’s a chance that if I chain smoke cigarettes for 50 years I won’t develop lung cancer. Or that I’ll never get in a car accident, or that my home will never be broken into or catch fire. Those are all possibilities, but people generally don’t like to take big risks with our health, or important purchases like cars and homes without having an insurance policy.

With Earth’s climate, there is no insurance policy. Either it remains stable and habitable or it becomes increasingly unstable and uninhabitable. In that sense the smoking analogy is quite apt. The more we smoke, the more we increase our chances of developing cancer. The more carbon pollution we dump into the atmosphere, the more we increase the odds of destabilizing Earth’s climate. We can either take that risk, or we can cut down our smoking or carbon pollution to minimize it. 

As it stands, climate change may represent humans’ worst-ever risk management failure, and climate inaction is decidedly anti-conservative.

Wrong on economics

Currently, most Republican policymakers don’t want to take any action to curb America’s carbon pollution (with the exception of about 10% of House Republicans). Like Rick Perry, they will often cite concerns about economic impacts to justify climate policy opposition. That’s exactly backwards.

In reality, climate inaction is the expensive route, and climate polices could potentially save tens of trillions of dollars. That’s the conclusion not of some tree-hugging environmental group, but of Citibank – America’s third-largest bank. Citi Global Perspectives & Solutions published a report in 2015 finding that investment costs alone in a climate action scenario would be $2 trillion lower than in an inaction, fossil fuel investment scenario. In other words, even if the 97% consensus is wrong, investing as though it were correct would save money. And if the 97% consensus is right, Citi found that slowing global warming would save tens of trillions of dollars more.

It’s not just the Citibank report; there’s a 95% consensus among economists that the US government should commit to reducing greenhouse gas emissions. Only 1% of economists disagree. 41% of economists think climate change is already hurting the global economy, 63% think it will by 2025, 89% by 2050, and 97% by 2100.

Wrong on ethics and morality

Sadly, today’s wealthy policymakers won’t feel the impacts of their climate policy obstruction. Today’s youth, and especially people in poorer countries who are least responsible for the problem will most suffer the consequences.

America is the world’s biggest net carbon polluter, one of the world’s wealthiest countries, and has joined Syria and Nicaragua as the only countries rejecting the Paris climate agreement. Nicaragua objected that the agreement was too weak, and Syria was mired in a civil war. Essentially, Trump and the Republican Party stand alone in rejecting the need for climate action, despite the country’s responsibility for the problem and resources available to address it. We’re forcing the rest of the world to clean up our dangerous mess. It’s a grossly immoral and unethical position.

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Comments 51 to 72 out of 72:

  1. NorrisM:

    In your fourth paragraph, you pose two questions that indicate you still are not recognizing what global climate models can and cannot do. Let me try to provide some sort of explanation.

    The first question is If the models are capable of predicting the future then they should have had an answer for the supposed "hiatus"

    But the models are not capable of predicting short term variability, such as El Nino events. They do have El Nino events, but the timing is more or less random and does not match the exact sequence of a particular set of years. Different model runs with slightly different starting conditions will place El Nino events at different times.

    Thus, you can't use the timing of El Ninos and related temperatures to test model skill. If El Ninos are simulated with a similar frequency and magnitude as the real world, then the model has skill even though the timing isn't exact.

    Let us take a non-climate model of a familar concept as an analogy: tossing a coin. With a fair coin, there is a 50:50 chance of heads or tails with each toss, and I will model a sequence of ten tosses using a spreadsheet with a random number generator. I will repeat the model simulation 9 times. Here are the sequences, with the counts of heads and tails:

    1.    HHTTTTHHTT    4    6
    2.    TTHHTHTTTT    3    7
    3.    TTHHHHHTHH    7    3
    4.    HHHHHHTTTT    6    4
    5.    THHTTTTHTT    3    7
    6.    THHTTTHHTT    4    6
    7.    TTTTHTTHTH    3    7
    8.    HHHTTHTHTT    5    5
    9.    HTHTHTTTTH    4    6
    10.    TTHHTTTHTH    4    6

    Now, you may notice that there are 10 sequences, not nine. I also did one real coin toss sequence, and generated one more random number to decide where to place it in the order. One of the above ten sequences is real; the other nine are modelled.

    Note that none of the sequences are the same - therefore none of the model sequences exactly matches the real sequence. You cannot conclude from this that the model is wrong, however. It may be, but you can't tell that from this data.

    Can you identify the real sequence? If not, then the nine modelled sequences are realistic enough to pass this sniff test. And with the global temperature record, we can have many model runs but only one real sequence, just as I have done with the coin tosses.


    On to question 2: "If the physics explain this 25 year increase in temperatures (1975-1998), how do you explain the temperature increases and decreases that I had referenced earlier, especially the .3C rise from 1900 - 1940 or so."

    The earlier period is more difficult to deal with because we do not have sufficient data to force the models - measurements of essential variables such as radiation, atmospheric dust, etc. were fewer and less accurate.

    Again, I will use simple analogy with a simple model.

    • My model says that A + B = C.
    • Today, I know that A = 3.03 and B = 7.64, and that C = 10.71, with all values uncertain to +/-0.05.
    • My model predicts that C = 10.67 today, with an uncertainty of +/-0.07 (because of the uncertainty in A and B). My model is 0.04 off the known value of C, but within the error bars of both my estimate and the measurement.
    • In the past, A was 4.1 and B was 3.7, both with uncertainties of +/-0.5. The model says C would be 7.8+/-0.7.
    • The known value of C was 8.5+/-0.05. The model error of 0.7 is not necessarily due to a poor measurement of C or a poor model, however - it could be due to the lack of knowledge of the input values A and B. The error is larger, but the uncertainty bounds are also larger.
    • I could play with the values of A and B to get better agreement, but there is little point. Without a time machine to go back and get better measurements, I would not know if the better agreement is because I got a better value with a good model, or whether I just managed to get the errors in A and B to offset the errors in the model.

    Does this clarify what can and cannot be done with a (climate) model?

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  2. NorrisM @49

    You might find this helpful. I'm exploring it myself, to try to make sense of it all.

    This link is a graph of models versus reality up to 2015. The first two graphs are the most relevant and clearest

    You can see temperatures are generally following models reasonably well, but as I said before slightly under, but not by much. Last years temperatures, 2016, means they are even less under.

    Please note, like the comment above says models cannot ever exactly predict year to year temperatures, wiggles, or decadal temperatures. They predict longer term trends approximately, over 20 years,  and the general track, and predict end point temperatures which is what concerns us most.

    The pause originally appeared large, and outside of what models predicted as expected natural variation (wiggles). You can see in the graphs in the link above it isnt actually so large. Recent temperatures and better data on the pause has changed things.

    The warming from 1900 - 1940 has been attributed in almost all reseach to a combination of CO2 and increased solar activity. It should be pointed out solar activity sunspot cycles only has a limited impact over short periods 1 degree maximum for short periods.

    The flat period from 1940 - 1970 (approx) has been attributed to high particulate emissions from the post war industrial boom.

    The warming from 1970 - currently has been almost 100% attribted to CO2.

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  3. Thank you for that explanation, Bob Loblaw @51, though I am not sure that is at the heart of NorrisM's line of inquiry.   I suspect he wants black-and-white certainty — without regard to questions of probabilties & the consequent need for prudent risk-management of planet Earth.

    Nigelj @52, some of those graphs have not been updated with the latest real-world temperatures (which show a better match to the old "predictions").

    NorrisM @49 , you are making a mountain out of the molehill that was the Koonin-chaired panel of scientists back in early 2014.

    Metaphorically speaking : in a scientific ocean rivalling the Pacific in size, the Koonin/APS review was a momentary ripple in a lagoon.    And a ripple that was stillborn. [ er, sorry about the mangled metaphor ;-)  ]

    NorrisM, you have made the mistake of equating the Koonin/APS review with something like a major case before the Supreme Court.  But the situation was quite different.  Doubtless the scientist-participants would have done a bit of "brushing up" before the panel met — but there would have been nothing like the lawyers' preliminaries where weeks of careful polishing of comprehensive presentations (prepared by teams of high-powered lawyers/barristers) before battle commenced.

    Furthermore, the matters discussed were only a tiny section of climate science.  And from my reading of the transcript, nothing much came forward that was substantive or in any way conclusive.  Really, the result was stillborn.   So I don't see how you can justify cherry-picking such a "non-event" and drawing any lessons from it.

    (B)  You do well, to put a "tick mark" of suspicion against some of the denialists (such as Lindzen).   Not only does their case not hold water, but you can see how their underlying thinking is severely tainted/motivated by non-logical emotional bias.   Lindzen, for instance, holds that our planet was created by Jehovah [i.e. the pre-Christian deity] as a self-correcting mechanism, and so it cannot deviate from the ideal narrow condition suited to humanity.   Or so Lindzen seems to believe.   Such is the power of emotion-driven illogical thinking, that it results in Lindzen being quite unfazed that (repeatedly!!) the physical evidence keeps showing him to be severely wrong.

    Self-deception and delusion are the essence of climate denialism.

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  4. The comment NorrisM @49 has turned full circle to address what NorrisM described in an earlier interchange as "what also troubles me in everything that I have read so far on climate change." That interchange ended with NorrisM withdrawing to read up on SkS comment threads and for some reason "the Nigel Lawson GWPF site."  It would be good to nail this discussion rather than have yet another run round the houses.

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  5. Bob Loblaw @51.

    If I understand your first example, this would suggest that it is appropriate to "average" the various model results and compare them with the actual observations.  In your example, the model of 50:50 chance is correct because the average of the models is bang on with the theory. 

    Although statistics is not my strong suit (I have to admit I did take one course in my undergrad degree (BA Economics), do I understand that a bell curve of the GCM results are within one standard deviation.  If so, what percentage of one SD?

    I do not know if you are able to do this but if you were to elimate both the 1998 El Nino and the 2015-2016 El Nino from the data, how would the models stack up to actual observations excluding those events?

    As to the second example, I think you are saying that the observational information is not good enough to explain the increase in temperature.

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  6. nigelj @ 52 and scaddenp @ 50.

    I certainly get the message that models cannot predict 10 year cycles.  I guess what I should have asked Bob Loblaw are the model predictions and their variance based upon: 1.  Period 1900 to present; and 2. 1975 to present.

    Thanks nigelj for your explanations of the periods of temperature increase and decrease (or levelling off) during the 20th century.  I know that one of the pet peeves of Lindzen (from one essay by him) has been the use of aerosols to "adjust" models.  All very confusing for the layman.  See my comments to Eclectic and MA Rodger below.

    But if the models are within one SD over 20 years then this is certainly material information.  Reading Christy's chart you would not think so.

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  7. Eclectic @ 53 and MA Rodger at 54

    My reply to MA Rodger is that I started that process of reading the thread starting in 2008 and was prepared to slog through it all, knowing after a very short while that I would hardly understand most of the technical information.

    That was until I heard that Perry may very well undertake a Red Team Blue Team investigation which, for a lawyer, is the way to go because it forces both sides to mount their evidence and bring their experts. 

    In fact, Eclectic, although I fully agree with your comments on the APS Panel regarding preparation ahead of time, we should have what is the equivalent of a Supreme Court hearing on this.   It still troubles me that Santer and Held did not speak up more strongly on the discrepancies (and I note no one has yet commented on that).   But the problem I had with both the APS enquiry and the Berkeley Red Team Blue Team project is that they did not follow through with what we have come to expect in a common law justice system.  An independent judge (or judges) listening to both sides of the argument and their experts, that panel of judges coming to a decision, and then providing their reasons.   Any dissenting judges would also provide their reasons.

    In the case of the APS Panel, the Board of Directors one year later came out with a revised statement that basically was the same as the previous one (after backing off of the word "incontrovertible") but without providing any reasons. 

    In the case of the Berkeley project, Mueller (sp) really acted like a judge in the European system where the judges get actively involved in searching out for evidence on their own.  This system may or may not be better than our adversarial system but I like our adversarial system because it is open.  Basically, Mueller hired his own guy and came up with his own reasons and ignored the evidence of both sides or certainly did not use it. 

    What we will be relying on as Trump takes a run at our institutions, is an independent judiciary with no axe to grind.  That I am sure is why Judith Curry does not want the NAS to conduct the review.  I fully understand that some scientific bodies felt that they had to make a stand on the question of climate change but it does then hit their independence when later asked to preside over any adversarial process to consider the very issue upon which they have come out with a policy.  

    When the APS came out with their statement after the Koonin chaired APS Panel, I am sure that one of the discussions amongst the Board was how much they could  "modify" their statement now that they had taken a stand without causing a major issue not just in the press but in the world. 

    So if there is to be a Red Team Blue Team organized by the Department of Energy, it would probably be better to place the responsibility in some agency that has not come out one way or the other on this issue.  I still have some misgivings with this rather than the NAS but it might be that the NAS itself would pass on it.

    For those that say this is a "waste of time" I can only repeat myself. It is called RealPolitik.  As lawyers, we used to refer to the "Golden Rule".  He who has the gold makes the rules.   I hate to say it but you know who makes the rules in the US at this time and for the foreseeable future.  That is why I think the climate science community should sign on to this process and be a part of it. 

    Perhaps this website should set up a separate section to consider the issues that should be considered by such a Red Team Blue Team. 

    Who knows, perhaps Trump will only sign on to this process if he has some assurances that 'he will win".   If the panel is "weighted' one way or the other it would destroy its credibility.  From what I have seen of Koonin, I do think that he would ensure that the panel had representation from both sides but that the majority of the panel were truly independent. 

    I truly think that the Red Team Blue Team structure should be modified to require the panel to provide its recommendation and reasons for its decisions.  As with judgments of any appellate body, there could be dissenting opinions.

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  8. NorrisM, I have replied to your comment here on the original, appropriate thread.

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  9. Norris M @56

    You say "I do not know if you are able to do this but if you were to elimate both the 1998 El Nino and the 2015-2016 El Nino from the data, how would the models stack up to actual observations excluding those events?"

    Look at figure 3 in this graph below. And also the article in general.

    It removes all el nino and la nina events from the trend. It's from work by Foster and Rhamstorf. You can plainly see what is left is a roughly linear trend of clearly increasing temperatures, and quite steep. It's therefore clear el nino is not the reason for increasing temperatures.

    A picture paints a thousand words, and when there are arguments and disputes its best to go back to the basic data as in a graph or table.

    Unfortuantely it doesnt have model predictions grafted on, but you will find the models run in the early 1990s have predicted this trend pretty well, but are still slightly under in the last few years as I have said. They are not sufficiently under to be some huge concern, imho. It's certainly false and at least a huge exaggeration to say the models failed to predict the pause and / or dont predict temperature trends adequately.

    It's believed models are slightly under, as oceans are absorbing more heat than first thought, and this is delaying warming slightly. But a delay is only a delay.

    Regarding Santer and Held not talking up over discrepencies. I dont know why, and we may never know why and there could be many reasons, some people are a little shy by nature for a start, or just get side tracked by other issues they feel are more important. Dont read things into things.

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  10. NorrisM @57

    You still like this red team blue team approach, and appear to want it run as a court process etc. I just think you are very wrong on both issues.

    I note you appear to be a lawyer, so do have vested interests or a probable bias. I can appreciate this, and I would maybe do the same in your shoes and want a court approach, but it's still a bias.

    I think courts or similar processes are no place to decide matters of science. With respect neither judges, lawyers or lay people on juries are in any position to analyse such complex science and pass reasonable judgement.

    Not even expert witnesses could resolve the issue. Climate science runs to over 12,000 research papers and all are important, and its hard to see your process dealing adequately with that.

    We are seeing similar huge difficulties in complex  financial fraud cases, which are beyond the expertise of judges and juries etc, but in those cases it's hard to do anything other than a court process.

    With climate science its both feasible and far more appropriate and sensible to have large review bodies like the IPCC. This was designed specifically because of the problems with court style processes and even inquisitorial processes as in the european legal system.

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  11. NorrisM: I have also posted a comment over on the models thread.

    As for your statement "I think you are saying that the observational information is not good enough to explain the increase in temperature."

    No, that is not a proper interpretation. The observational information is good enough to explain the increase in temperature, for the most part, within the uncertainty limits of the observations. It's just that the uncertainty is larger the further back in time you go, and thus the power of explanation is weaker (and may always be limited).

    The error in logic that is often made is to think that a larger difference means the models have failed. They have not, because we cannot know if the larger difference is due to model error or poor measurement. We also have difficulty in using that difference to improve the model, because we may be chasing an observational error, not reality.

    A lot of effort is made to try to find additonal sources of information on the past. We can't go back and measure temperature at weather stations again, but we can find more lake sediments, more tree rings,, more ice cores, etc. and improve the methods of deriving temperature information from them, though.

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  12. ...and lastly (for the moment), if NorrisM really wants to see what a court of law would do when "the two sides" face off in court over climate, I suggest he read this article describing the results of a recent court case.

    Hint: the "skeptic" side does not come off looking very good.

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  13. The peabody case was interesting. Deniers on whole are trying to convince themselves or a gulliable public that they have a point. That is much harder to when points can be debated by actual scientist. One reason I would like to red-blue team approach and bring on the popcorn. On the other hand, some of advocates of the approach are just looking for soft money and its hard to feel good about that.

    I suspect that there are some astute GOP people that would see the likely outcome of the red/blue team approach and quietly can it. I love the assumption that climate scientists are blue team. Maybe nowdays most are given way they are treated, but certainly wasnt always the case. Which team is Richard Alley playing for?

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  14. My understanding is than the IPCC process is far more robust than a USA Red Team - Blue Team Competition would be.

    I see the IPCC process as a rainbow team approach (plus teams beyond the visible spectrum) all having to agree on the understanding/wording of an issue with the restriction that the wording must be supported by, and be consistent with, all of the available information brought into the evaluation by the global spectrum of paticipants.

    A result of a USA Red Team - Blue Team Game (potentially gamed significantly by a few powerful wealthy people and how it gets covered in the media) could not be expected to come close to the comprehensiveness and legitimacy of the IPCC results.

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  15. OPOF @64 , the red-team/blue-team approach to climate science may be the current "talking-piece-du-jour" for denialists & ultra-right-wing politicians.  But I think they will meet you with hostility if you suggest a "rainbow" approach  ;-)

    Scaddenp @63 , the GOP politicians could go either way, about setting up (or not) a red-team/blue-team Investigation or Inquiry.   Certainly they would like to set up a rigged inquiry : and certainly they know that a truly fair/impartial inquiry would inevitably show the denialists to be completely wrong.

    Personally, I think the genuine climate scientists should reject any kind of inquiry (of the proposed type) and they should state assertively A/ that a "new" red-team/blue-team assessment would be a great waste of the taxpayers' money, and B/ that such assessments had already been done and are always being done continually every year by by large numbers of scientists as part of normal everyday science.

    The anti-science politicians in power might well decide to try to carry out a red-team/blue-team "Inquiry", despite a high certainty of an adverse decision (adverse to them).   Because they would gain in the short term (and if they can't rig a favorable result, then they will still gain by drawing out a fair Inquiry for many years. )

    They can beat the genuine climate scientists over the head for not participating in the Inquiry — for the non-participation will look bad to the non-thinking public.   And if participation does occur, then [the GOP politicians] will publicly use that participation as an admission by the scientists that the mainstream science is so uncertain & doubtful, as to be very much in need of a thorough inquiry.

    The anti-science politicians would gain tactical advantage in forestalling journalists' questioning of (lack of) Climate Change policy and (lack of) action or leadership :-

    — "The science is not settled, obviously."

    — "We are actively looking into these questions."

    — "It is premature for me to comment on that."

    — "No, I can't comment, because the matter is [sub judice]."

    — "As soon as the Inquiry is finished, we will study its report and decide on appropriate action."

    In summary : it would be a very unskilled politician who couldn't arrange for the Inquiry to be stacked with so many submissions, as to take many years to complete.    An excellent way to continue to stonewall, without being perceived as stonewalling!

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  16. Climate scientists need to be careful about refusing to participate.  If the Red team is Lindzen and Monkford the Blue team is Spencer and Curry it might lead to a refutation of the IPCC report.

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  17. Quite so, Michael Sweet @66 .

    Truthful science is going to get a hammering, either way.   it is a Lose/Lose situation, unless some smart thinking finds a way to mitigate the harm.

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  18. Climate scientists should continue to increase awareness and better understanding, including rebuking and rebutting whatever ridiculous impressions/ideas a USA Red Team/Blue Team creates. And that includes pre-emptive efforts to denounce/discredit the validity of a USA Red Team - Blue Team exercise given the already completed and far more legitimate Broad Spectrum evaluation by the IPCC (Broad hoped to be not as jarring to the snowflakes in the denier mob as the Rainbow Plus I previously used to describe it).

    There are so many ways to delay the required correction of developed behaviour in the USA, and so much desire to maintain the undeserved perceptions of prosperity and opportunity, that it appears that the wealthiest USA deliberate delayers will need to be very effectively targeted by international sanctions.

    That is the globally established non-violent way of addressing trouble-makers who will not be "... moved by rational consideration of distant - other than short-term personal interest - motives ..." (a portion of one of my favorite statements by John Stuart Mill in "On Liberty").

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  19. To be clearer:

    "... moved by rational consideration of distant  motives ..." with 'distant' understood to mean 'beyond short-term personal interest - consideration for all other life and the distant future'.

    The need to chance the course of human development to achieve the Sustainable Development Goals and work to expand/improve those goals with Good Reason could be an effective part of the presented criticisms of actions by the likes of Team Trump. Doing so would expose that many other actions by the likes of Team Trump are damaging/unacceptable, not just their stance on climate inaction.

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  20. nigelj @ 55

    Thanks for the reference to the graph removing ENSO.  This was interesting. I agree it would be nice to have also had the average model projections grafted onto this chart but it is helpful to see the Raw Data comparison to the temperature increase removing the effects of ENSO.

    So this chart shows the "line" of heating attributed to anthropogenic causes which is the combination of CO2 plus the positive feedbacks primarily from water vapour.  This line should match the projections of the models in the "business as usual' case although I appreciate that this would not be linear given the accumulating effect of existing CO2 accumulations in the atmosphere.  

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    Moderator Response:

    [PS] Other commentators have replied to you on the correct thread. Please do likewise for anything further about models.

  21. NorrisM @70,  I just couldn't find a graph of that. But I have visually compared the last 30 years of what models predict, against actual temperatures, with el nino removed. Models are still over estimating temperatures, but its just not by very much. I think that is the key thing its just not that different. 

    And it would only take a few more years of high temperatures to cancel this discrepency, and it should be noted 2017 is already showing quite high temperatures so far. It would also only take a slightly higher than anticipated acceleration near the middle or end of this century.

    One theory is that oceans are simply absorbing more heat than originally thought, but that energy won't stay in the oecans forever (in simple terms)

    I have always been upfront I'm not a climate scientist or any form of expert on it, but I do have a reasonable university education in a variety of things, and  knowledge of the general climate debate. I'm interested in the science, but also the psychology, economics, and polictics, as these are personal interests of mine, and I did some psych. at university. So the climate issue encapsulates all the things I'm interested in, sort of by coincidence.

    I think what counts is the long term trend once you get past about 20 years at least, so century scale predictions count most. These are based on the effects of CO2 and basic solar cycles that can be quantified and predicted. It's not possible to predict the wiggles along the way, and ten year periods, as ocean cycles are a bit random. That's my reading of the situation, and Im prettty clear on this in my own mind.

    If we had experienced a pause of 20 years, I would say this would have been totally unanticipated, and our climate understanding would have been poor, but we just havent seen that. It's more of a 6- 8 year blip at most, if you look at any temperature data like giss. The overall upwards trend in this data is also just very clear now.

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    Moderator Response:

    [PS] Please follow other commentators and put discussion of model in the correct thread. A reply to NorrisM there already points to a page with the graph he has asked for. (and note of course obs are within error bars. Please do not ignore error bars when discussing model fit -that is just another way to avoid science in preference for rhetoric).

  22. NorrisM @55,

    I respond elsewhere.

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