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Latest Posts


2015 SkS Weekly Digest #36

Posted on 6 September 2015 by John Hartz

SkS Highlights... El Niño Watch... Toon of the Week... Quote of the Week..He Said What?... SkS in the News... SkS Spotlights... Poster of the Week... Coming Soon on SkS... SkS Week in Review... and 97 Hours of Consensus

SkS Highlights

Citi report: slowing global warming would save tens of trillions of dollars by Dana drew the highest number of comments of the rticles posted on SkS durig the past week. Attacting the second highest number of comments was Denial101x MOOC - Full list of videos and references at your fingertips by by Larry M & Baerbel W. 

El Niño Watch

A mature and strong El Niño is now present in the tropical Pacific Ocean and is likely to strengthen further. This year’s El Niño event is the strongest since 1997-1998 and is potentially among the four strongest events since 1950, according to the latest Update from the World Meteorological Organization.

The peak strength of this El Niño, expected sometime during October 2015 to January 2016. Its impacts are already evident in some regions and will be more apparent for at least the next 4-8 months.

El Niño expected to be strongest since 1997-98, WMO Press Release, Sep 1, 2015 

Toon of the Week

 2015 Toon 36

Quotes of the Week

ANCHORAGE — President Obama on Monday issued a global call for urgent action to address climate change, declaring that the United States was partly to blame for what he called the defining challenge of the century and would rally the world to counter it.

“Climate change is no longer some far-off problem; it is happening here, it is happening now,” Mr. Obama said here at an international conference on the Arctic. “We’re not acting fast enough. I have come here today, as the leader of the world’s largest economy and its second-largest emitter, to say that the United States recognizes our role in creating the problem, and we embrace our responsibility to help solve it.”

Obama Makes Urgent Appeal in Alaska for Climate Change Action by Julie Hirshfeld Davis & Steven Lee Myers, New York Times, Aug 31, 2015 

"We all would want to see this baby born," Christiana Figueres, head of the U.N. Climate Change Secretariat, said of the U.N. agreement meant to chart ways to fight global warming beyond 2020 by almost 200 nations.

"Of course we are all impatient, of course we are all frustrated," she told a news conference, referring to efforts to pin down emissions cuts to limit heatwaves, floods and rising sea levels. "We are ... on track with the Paris agreement."

At UN climate talks, growing frustration at "snail's pace" by Alister Doyle, Reuters, Sep 4, 2015 

He Said What?

Appearing on HBO’s Real Time with Bill Maher, GOP presidential hopeful Rick Santorum doubled down on his skepticism of man-made climate change.

Santorum made two claims to back his point. First, in a large survey of climate scientists, "57 percent don’t agree with the idea that 95 percent of the change in the climate is caused by CO2," according to Santorum. (We found that claim False.)

Second, Santorum said that a widely cited figure of scientific consensus on climate change — 97 percent — has been debunked by the "head" of the United Nations Intergovernmental Panel on Climate Change, he said.

"The 97 percent figure that’s thrown around, the head of the UN IPC (sic) said that number was pulled out of thin air. It was based on a survey of 77 scientists," he said on Aug. 28. "Not even 97 scientists responded to that survey."

Santorum: UN climate head debunked widely cited 97% climate change consensus figure by Linda Qiu, Politifac, Sep 2, 2015

SkS in the News

The following paragraphs are excerpted from Linda Qiu's Politifact article, Santorum: UN climate head debunked widely cited 97% climate change consensus figure:

Tol was specifically referring to a 2013 survey by John Cook, who studies climate communication at the University of Queensland.

Cook’s study found that among over 4,000 studies that took a position on man-made climate change, 97.1 percent "endorsed the consensus position that humans are causing global phase" and 97.2 of 1,300 authors who responded agreed with the position.

Tol takes issue with Cook’s methodology. By his analysis of Cook’s data, the real figure is around 91 percent. (Cook replied critiquing Tol’s methodology and standing by his survey’s original finding of 97 percent.) 

Lindsay Thurman begins her Plos blog post article, Getting the [Climate Change] Story Straight with:

With the recent publication of the 2014 IPCC report on Climate Change, the 2014 US National Climate Assessment, and the upcoming Paris 2015 UN Climate Conference, it’s no surprise that the scientific consensus on human-caused climate change has reached approximately 97%.

SkS Spotlights

CDP (Carbon Disclosure Project) works to transform the way the world does business to prevent dangerous climate change and protect our natural resources. We see a world where capital is efficiently allocated to create long-term prosperity rather than short-term gain at the expense of our environment.

Evidence and insight is vital to driving real change. We use the power of measurement and information disclosure to improve the management of environmental risk. By leveraging market forces including shareholders, customers and governments, CDP has incentivized thousands of companies and cities across the world’s largest economies to measure and disclose their environmental information. We put this information at the heart of business, investment and policy decision making.

We hold the largest collection globally of self reported climate change, water and forest-risk data. Through our global system companies, investors and cities are better able to mitigate risk, capitalize on opportunities and make investment decisions that drive action towards a more sustainable world.

Coming Soon on SkS

  • Volcanic vs anthropogenic emissions update (jg)
  • Republicans keep saying we should listen to climate scientists, so why don’t they? (Dana)
  • The Exception Extinction (howardlee)
  • Guest Post (John Abraham)
  • Scientists pinpoint Arctic warming hotspots behind severe northern hemisphere winters (Robert McSweeney)
  • Weekly News Roundup (John Hartz) 

Poster of the Week

 2015 Poster 36

Hat tip to Oil Change International

SkS Week in Review

97 Hours of Consensus: Marcia McNutt

97 Hours: Marcia McNutt

Marcia McNutt's bio page & Quote source

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Comments 1 to 16:

  1. This is where our expectations of science went terribly wrong.

    Tol takes issue..saying its only 91% consensus not 97% as John Cook claimed. But its unusual to adopt a denial stance when you already know you believe its at least 91% probable that John is right all along?

    The scientific truth begins when at least a 95% probabilty is reached. 91 is only 4 away from 97 or 4% of it. Both figures are so high as to mean the very same thing our planet is troubled and we are the only ones who can do anything about it.

    We need wake up now, stop wasting time on semantics, modify/fastrack our methods considering all, first looking for medium strong trends and only then distilling out the scientific. 

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  2. Question: Do we accept the veracity of E=MC² or F=MA because 97% of  physcists say so?

    I understand that climate is a nonlinear chaotic system, but it's that a reason to be even more circumspect? I recently heard a talk by William Nordhaus at Yale, certainly no denier, where he showed the number of data dependencies in models, that have not been isolated. Specifically, when we look at paleoproxy data we see that temperature and carbon fluctuate in tandam at fairly regular intervals over the last 400K years. However, as of 2013 we do not know to what extent carbon forces temperature and temperature forces carbon, or excatly why they fluctuate if indeed one expects a reenforcing feedback loop is present.

    Has this issue been addressed and resolved?

    (Nordhaus' pertinent comments at 7:22)

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  3. Ignaz @2, if E=mc2, then it is not true that F=ma.  Rather,



    and a∥ is the acceleration parellel to the instantaneious velocity of the object, and a⊥ is the acceleration perpendicular to that velocity.

    This is not mere pedantery.  If you are going to argue that "we know" not by scientific concensus but by the actual data, then you have to adopt a consistent perspective that fits that data, not swap between more exact and less exact (and falsified) theories in a single breathe.  That you treat equally to formulas, one of which is the best available (ie, not formally falsified and substantially tested) theories and an approximation retained by consensus as a convenience for many common situations seriously damages your thesis.

    Even more damaging is that the approximation is adequate for everyday experience.  More devestating for your case is the fact that the much worse approximation from Aristotelian dynamics is still adequate for the vast majority of peoples actual experience.  It is only when we measure the motion of objects in a precise manner that Aritstotle's theory (or at least the medieval developments of that theory) are shown false.

    The result is that for me, and the vast majority of others; we do accept that E=mc2, and F=ma because (we have been told that) it is the consensus view of physicists.  No person with only a high school education in physics has done enough experiments to verify Newtonian dynamics as a close approximation of the truth, let alone Relatitivistic kinematics.  Very few actual physicists have done so either.  Even for most with an actual interest in the topic, they are only aware of a few historically influential experiments, without being aware of the vast number of other experiments actually supporting the theories in question.

    So, we (as in the fraction of the general populace interested enough to actually follow the science) know these things (whether in dynamics, kinematics, or climate science) because we accept a scientific consensus, and know enough that the consensus itself  was not formed by accepting a consensus but by following data.  But unless you have an extensive research career covering both theoretical and experimental aspects of the topic, you do not know these things independently of accepting some things because they are the consensus view.  (Indeed, even then you must accept the consensus on peripheral factors necessary to carrying out your experiments.)

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  4. Noone is claiming that the veracity of a scientific question is settled by vote - the extent to which anything in scence is "true" is dependent on constant comparison of theory and results by experienced scientists. The opinion of relativity deniers doesnt weigh much unless one them someday publishes a reproducable result which would call the theory into question and this applies in climate too.

    The importance of understanding what the extent of consensus is among climate scientists is a/ to counter the denier myth that consensus doesnt exist and b/ because the consensus science position is the best guide to policy action in any sphere.

    Weather is chaotic, climate is not as far as we know. See here .Climate is determined by the energy balance and sets the bounds in which the complex dance of weather occurs. Ask yourself why summer average temperature is higher than winter average temperature - because the energy input into the system is higher. CO2 is likewise.

    CO2 can be both a forcing and feedback. In the ice-age cycle, the controlling forcing is the highly predictable change in solar distribution. CO2/CH4 are very slow feedbacks that magnify the effect of the solar forcing and fortunately, temperature-induced increases in CO2 and CH4 are slow enough not to have significant impact in next hundred years.

    "However, as of 2013 we do not know to what extent carbon forces temperature and temperature forces carbon, or excatly why they fluctuate if indeed one expects a reenforcing feedback loop is present."

    What on earth is your source of this claim? If Nordhaus, then he is wrong. See for instance Hansen and Sato 2012 - look at Fig 2, and lower 2 comparisons of calculated temp to measured.

    It is best to find out about science from scientists. The best way to do that would be to read the IPCC WG1 reports. All the text in main report linked back to published science that the text is based on.

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  5. Ignaz @2:

    "...a talk by William Nordhaus at Yale, certainly no denier, where he showed the number of data dependencies in models, that have not been isolated..."

    At 7:23 in the video, Nordhaus is talking about the fact that different estimates of climate sensitivity use the same or overlapping data to make those estimates, ie, the same twentieth century temperature record and the same twentieth century forcing record (in some cases), or the same ice core records (in others).  It follows that those estimates are not stastically independent.  That has nothing to do with the independence of climate models.  You have completely misrepresented what Nordhaus was saying (through ignorance, I suspect).

    "However, as of 2013 we do not know to what extent carbon forces temperature and temperature forces carbon..."

    Nonsense, and nor is it what Nordhause is saying.  Specifically, we know that CO2 concentration increases by approximately 7.7 ppmv per 1 degree increase in global temperatures (likely range of 1.7-21.4 ppmv/oC).  Nodhaus's estimate comes out at a 2.23% increase per degree C, or 6.3 ppmv/oC at 280 ppmv initial CO2 concentration.  We also know that temperature increases relative to CO2 concentration at approximately 3oC per doubling of CO2 (likely range of 1.5-4.50C per doubling).

    Not knowing values to arbitrary precision is not the same as not knowing the values.  Nor does Nordhaus suggest it is.  His discussion of what we know relates only to the limits of the method he discusses in his video.  Multiple other methods can be, and have been applied to the problem.

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  6. "...temperature and carbon fluctuate in tandam at fairly regular intervals over the last 400K years"

    Is that a reference to Milankovitch Cycles? It sounds like it is, but those are not limited to only 400K years.

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  7. I was always taught that 'e' certainly does not equal 'mc2'....

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  8. @4, the debate is consenus of opinion versus consensus of fact.

    A nice distraction but any politician using it has long term credibility problems as the groupthink will work out the complete disingenuous nature of the original fake dichotomy and follow the money trial the made it so!

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  9. BBHY @6, the reference is to the Vostock icecore record which extends back 420,000 years:

    That has recently been extended back to 800,000 years for EPICA Dome C, but the more extended data is frequently ignored on the internet:

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  10. bozza @7, agreed, e certainly does not equal mc2.  Nor, come to that does E = mC2, or MC2.  At least, not in the standard notation.  But surely this does become pure pedantery.

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  11. It would seem I am a pedant without a cause...

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  12. The Proven Thing is the central tenet of Apocalyptic Cornucopianism  -  the fastest growing cult religion of all future times. 

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  13. Tom Curtis bozzza Cutting and pasting notion from Wikipedia aside, are you saying you know something Einstein did not? Or are you just playing games because I picked the wrong example for the point you know I was making?  Perhaps I used the wrong notation; perhaps the finer points are... whoopdy-doo! The point is that the veracity of the laws of physics, chemical reactions, etc., are not dependent on the number of scientist who accept them. In any case, I will run it by a physicist friend who is happy to answer questions without sarcasm and condescension.

    In any case, a consensus of opinion is exactly what the 97% trope is not. It is a disingenous attempt to create consensus where it is not clear one exists, since Cook threw out the abstracts that did not express an opinion and it is not unreasonable to speculate that the reason those scientists did not express an opinion as to AGW is because they felt the data didn't support expressing one. However, to remove that doubt would be fairly simple. Instead of throwing out all the abstracts that did not express an opinion, those scientist can be poll now. Moreover, care has to be taken how the questions are formulated. It is fairly easy, no pun intended, to force the statistical outcome of any poll by the way the questions and range of accepted responses is formulated. 

    In addition, in regard to Nordhaus, in his own words he expresses the trouble with "chicken and egg" problem in making definitive statments about temperature sensitivity to CO2 in the atmosphere, when the CO2/temperature dependency is not isolated. Incidently, it does happen to be true that every succeeding IPCC report since 1990 has lowered the range of predicted temperatures.

    And finally, and this is just a general question, is their anything like a double-blind study standard being imposed on climate studies? If so, what are they? (Links would be fine - no need to trouble yourself with a long condescending explanation.) If not, then what keeps the biases present in evey other scientific enterprise from creeping into this one? (Here feel free to by all means explain away - again, no pun intended.)


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  14. Ignaz - I strongly suggest that you take discussions of Cook et al to one of the relevant threads, where your rather poor attempt to reframe the data has already been discussed and (correctly) dismissed. I will in passing note that the abstract survey ratings were in fact more than supported by querying the authors of the full papers. Bzzzt.

    Your claim that projections have been lowered is, in fact, not correct, see the discussion of the 1990 FAR projections here, versus AR5 here (in particular, Fig. SPM 6), which projects 2C by 2100 for RCP6.0, just the median value seen in FAR. Your claim is therefore unsupportably wrong. 


    You've posted quite a bit of nonsense on SkS over the last few weeks, on multiple threads and in multiple directions, echoing many of the climate change denial blogs - none of which seems to hold up under examination. IMO your comments are just noise. 

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  15. Tom Curtis With all that verbiage on physics which you so enjoyed showing off, you still don't refute that whatever the approxiamtion to truth those formulas may or may not provide, nonetheless it is not by a poll amongst scientists that those answers are given. No one has to depend on a scientist's opinion on the matter.

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    Moderator Response:

    [RH] Empty assertions. If you want to continue to post here you're going to have to find some way to support the statements you make. Thus far you've been incapable of doing so.

  16. Ignaz @13, the point of physical precision is that anybody who knew how to derive the basic mechanics of general relativity would know that E=mc2 and F=ma are incompatible.  (General Relativity, by the way, because of the involvement of acceleration.)  Even if you have just an informed intuition on the topic, you would have suspected a problem about simply accepting both at face value.  Ergo, that you chose these as your examples shows that you, at least, accept these not because you know their derivation, and the observational tests they have faced, but because you understand them to have been accepted as part of the scientific consensus (without apparently realizing that the second is only accepted as a usefull approximation in non-relativisitic contexts).

    Ergo, we have this paradox.  You are citing as examples of scientific truths not accepted because of consensus, scientific expressions you only accept because you understand them to be accepted by the conensus of relevant physicists. 

    If you do not recognize how that undercuts your case, well I have come to expect sloppy reasoning from you in any event.  If you think pointing these facts out is condescending, that again only reflects (poorly) on you.

    With regard to Nordhaus, the chicken and egg problem only relates to the particular technique Nordhaus uses to explore those issues.  We can use additional data from other sources to break out of that problem.  Indeed, that is just what Nordhaus does for one side of the equation.

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