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Comments 1 to 50:

  1. Does providing information on geoengineering reduce climate polarization?

    Thanks for the kind and thoughtful suggestions, Tom and Glenn. There may be too much water under that bridge for further discussion with that particular relative. But I'll keep your hints in mind for future interactions with similarly recalcitrant loved ones.

  2. Glenn Tamblyn at 13:41 PM on 5 March 2015
    Does providing information on geoengineering reduce climate polarization?


    Maybe the key to getting him to think about it is to give him one or two key facts that support AGW and can only be rejected by rejecting opinions from conservative sources. Since he is a WSJ reader I assume he is Republican.

    Ask him why the US Defense Dept accepts AGW as the most serious future threat they will have to face and how they came to that conclusion - answer, they were involved in the core research into the properties of atmospheric gases, going all the way back to the 50's when they started designing heat seeking missiles.

  3. Does providing information on geoengineering reduce climate polarization?

    wili @7, perhaps you should ask him why he is accepting his climate science from the same people who deny the link between second hand smoke and health, reject the link between the HIV virus and AIDS, and who reject vaccination for measels etc?

  4. Does providing information on geoengineering reduce climate polarization?

    Many good points, sho. But at least while she was in office, Thatcher was lightyears ahead of Reagan on environmental issues: "Thatcher supported an active climate protection policy and was instrumental in the creation of the Environmental Protection Act 1990 and in founding the Intergovernmental Panel on Climate Change and the British Hadley Centre for Climate Prediction and Research in Exeter.Thatcher helped to put climate change, acid rain and general pollution in the British mainstream in the early 1980s"

    But the essential point is true--when the right in both countries (and in both parties in the US) handed over sovereign power to corporations, they insured that we would be living with much of the insanity we now face.

    The relative of mine who has the deepest science background--major medical researcher, dean of a major medical shool for many years...--flatly rejects the science of global warming, mostly based on the WSJ editorials he religiously. I'm not sure what exactly would alter his clearly ideologically based belief system. He certainly won't ever see little old me as enough of a scientific literate to question his dismissive statements.

  5. It's the sun

    Dan Pangburn - When total forcing changes, so does the climate in response. That changes the break-even point, and the imbalance goes away. 

    Now if the total forcing continues to change, as we see with our GHG emissions, the climate will follow along (albeit with a lag due to thermal inertia and slower feedbacks, primarily ocean heat content on the decadal level), but if the forcing ceases to change any imbalance will decay accordingly. There is no 'fixed offset' from a TSI change in the presence of a dynamic climate response.

    Short answer - a step change in forcing will cause a climate change, after which there won't be an imbalance to integrate. 

  6. New Series: Science Communicators – Why We Love Communicating Science


    I learned about climate change through personal experiences ferrying (flying) new aircraft to their new owners across the world.

    Can you be more specific?

  7. Does providing information on geoengineering reduce climate polarization?

    Adam C @3: I agree that the study did show that presenting subjects with a fictitious solutions scenario that did not offend their sensibilities produced a small effect in reducing polarization. My problem was not that the solution presented was fictitious, but that the framing of the solution bore no resemblance to reality.

    Had the results been presented as "here's what happens to acceptance/rejection of the science when subjects are presented with a bogus, pain-free silver-bullet solution", then I wouldn't have objected.

    Perhaps more emphasis on frank discussions about realistic solutions could provide a way of closing the gap between those who accept and those who reject climate science. I would like to know.

  8. Does providing information on geoengineering reduce climate polarization?

    @Adam, #3

    I agree, but then the result becomes trivial because anyone could have predicted that outcome, right? So why do the study in the first place ...

    I have seen Kahan speak on the results of this experiment before, but I had not seen what the subjects were actually presented. To me, it is obviously meaningless to present false information which caters to what a person wants to hear, then essentially finding what would be expected, namely the avoidance of one pathway over another. We know that, we do not need a study for that. What we actually want to know if whether presenting realistic geoengineering options as one of the wedges of mitigation and adaptation has an effect on the perception of climate science. That is what Kahan appears to claim, but now I see how he overinterpreted his research ...

  9. 2014 SkS Weekly News Roundup #33B

    John Baez has an interesting update on the Yamal craters.  Perhaps the most important new information is that some of the many circular craters on the Yamal peninsula are recent.  That has been determined by comparing satellite photos of the region.  Baez quotes extensively from an article, which says:

    "Professor Bogoyavlensky told The Siberian Times: ‘One of the most interesting objects here is the crater that we mark as B2, located 10 kilometres to the south of Bovanenkovo. On the satellite image you can see that it is one big lake surrounded by more than 20 small craters filled with water.

    "Studying the satellite images we found out that initially there were no craters nor a lake. Some craters appeared, then more. Then, I suppose that the craters filled with water and turned to several lakes, then merged into one large lake, 50 by 100 metres in diameter.

    ‘This big lake is surrounded by the network of more than 20 ‘baby’ craters now filled with water and I suppose that new ones could appear last summer or even now. We now counting them and making a catalogue. Some of them are very small, no more than 2 metres in diameter.’"

    This proves the formation of the craters has been an ongoing event over the last decade.  It follows that the current rate of increase in atmospheric methane already includes a contribution from the formation of yamal type craters.  The rate of formation could possibly accelerate with continued warming, but such an acceleration will result in an increase in the rate of methane increase rather than a sudden rapid rise (Shakhova event).

    Also of interest are anecdotal accounts of residents in the area seeing a flash at the time, and in the direction of the formation of one of the recent craters.  Such a flash would indicate the formation was literally explosive, with a significant proportion of the methane oxidizing when the crater was formed.  If true, that would indicate a far lower rate of methane release from these events than that estimated by David Archer at Real Climate.

    Finally, Baez links to an article by Chris Mooney assessing the risk of a methane lead disaster from such methane releases. 

  10. Does providing information on geoengineering reduce climate polarization?

    Why is England so polarised where in the Celtic Fringe (including the Republic of Ireland, where I live) climate denial hardly gets a look in? Even Scotland, with heavy dependence on North Sea oil revenues, is also a big developer of wind energy. 

    It correlates IMHO with Conservative politics - Margaret Thatcher, for example, was widely disliked outside of England, the Conservative party is basically an English party, and under her leadership Scottisn Nationalism got an enormous boost. I think Thatcher (and Reagan) did some necessary things, but they also gave big business unwarranted permission to interfere in the political process, something which seems to have also happened in Australia.

    Not that we problem-free here as regards climate change, but we have no Lord Lawsons, Tony Abbotts or James Inhofes. Or is we do, they work very quietly.

  11. Dan Pangburn at 06:53 AM on 5 March 2015
    It's the sun

    If TSI is a forcing, shouldn't the comparison on the graph be between the temperature change and the time-integral of the TSI which exceeds break-even?

  12. Does providing information on geoengineering reduce climate polarization?

    I think the study is relevent nonetheless. It's long been suspected that many "skeptics" aren't truly skeptical of the science, but rather they find the proferred solutions (taxes, regulations, international cooperation) to be politically unpalatable. They hate the cure, so they deny the disease.

    This study seems to bear that out. Offered a potential solution that doesn't offend their sensibilities, the subjects become much more willing to consider the problem. I think the authors were forced to invent a fictitious geoengineering solution in order to properly explore this question.

  13. funglestrumpet at 06:43 AM on 5 March 2015
    New Series: Science Communicators – Why We Love Communicating Science

    One name that seems to be missing from the above suggestions is Viscount Christophere Monckton of Brenchley. It would be really interesting to know why he does what he does. I don't think for one minute that he actually believes what he says, and anyway, as Potholer 54 has so clearly shown on YouTube, he contradicts himself a lot of the time. Perhaps there's money involved somewhere along the line, but would a peer, even an hereditary one who has done nothing to earn their title, deliberately harm his country for a few pieces of silver? Surely not, it might cost him his title.

    (Carefully removes tongue from cheek!)

  14. Pluto is warming

    Intermediate tab text is missing.

  15. Neptune is warming

    Max Plank institute link is broken (source moved).

    (posted in the corrct thread this time :D )

    ... maybe Sromovsky 2003 link too?

  16. Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????

    Ugh, too many tabs, sorry totally posted that in the wrong thread :( 

    it shoulda been in this topic -

  17. Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????

    Szwast 2006 link is broken (source moved).

  18. New Series: Science Communicators – Why We Love Communicating Science

    Well, I'm not a celebrity and don't wish to be one, but I have been teaching a series titled: "Global Warming; Proof or Politics".  The course is about what you already know if you're signed on to SKS, but for the people who sign up with me, they are curious and generally not "convinced" either way...until they have finished the course.  Dcrickette asked for somebody from the conservative side...there are quite a few of us, but we keep our heads down.  I am a lifelong Conservative Republican, once personally acquainted with Ayn Rand, used to never vote for a Democrat until I grew tired of Republicans ignorant about climate change.  I am a former instructor of government and international politics at an obscure college in Virginia and manage an organic farm in the Alleghenies in western Virginia.  I  learned about climate change through personal experiences ferrying (flying) new aircraft to their new owners across the world.  Rest assured that there are millions of Republicans that understand the threat of greenhouse gases...but they don't like to admit it to many of their Republican friends.  Blood and politics are thicker than water and aerosols.

  19. Does providing information on geoengineering reduce climate polarization?

    Thanks Andy.

    It does seem utterly bizarre to use dummy geoengineering data that is so far removed from reality. One wonders why the study didn't adopt a "tell it like it is" approach to the test subjects?

    On the topic of political polarization regarding climate change information: I'm sure that you, like many of us, remember Newt Gingrich's aspirations toward the Republican Presidential nomination were badly dented at the mere suggestion of Katherine Heyhoe doing a chapter in a then forthcoming book. 

    In the UK, I'm afraid the cross party leadership show of unity (let's avoid the word "consensus") is far weaker than portrayed. Although Labour and the Lib-Dems seem pretty much to agree that this is a clear and present danger, the Tory party is rife with division on climate change.

    The joker in the pack is, of course, the UKIP party. Come the General Election on the 7th May, I will be (pleasantly) surprised if UKIP does not end up with more votes and more seats than the Lib-Dems, as UKIP's official stance on climate change is simply frightening.

    Their Energy Spokesman, Roger Helmer, has openly questioned the linkage between CO2 levels and human activity, and talks glibly of "climate alarmism".  In their Policies for People statement, the first bullet point in the section devoted to Energy reads...

    UKIP will repeal the Climate Change Act 2008 which costs the economy £18bn a year

    I wonder if it's too late to put my name down for the one-way mission to Mars?


    cheers      bill f

  20. New Series: Science Communicators – Why We Love Communicating Science


    Calder is like Fred Hoyle, a brilliant British astronomer, who elucidated nuclear fusion in the stars, but who could not accept the Big Bang Theory (the name he created in derision, but it stuck). He also publicly doubted evolution, and theorised that the flu virus (indeed, life itself) came to the earth from outer space. 

    It is widely believed that Hoyle lost on a share of a Nobel Physics Prize because, when his peers received their awards, by that time he had embraced too many ideas in scientific disrepute.

    Hoyle also took up writing science fiction. I never read any of his books, but I would not hold such writing against him! Maybe his voyage into the world of fiction and the imagination played tricks on him.

    Hoyle's career, like Calder, shows that eminence and brilliance are no guarantee against ending up on the scientific fringe.

  21. Does providing information on geoengineering reduce climate polarization?

    Thanks. I had suspicions that there were problems with the Kahan study. Though there was a certain wry irony to the idea that some conservatives only accept gw science if spiced with schemes that at least one climate scientist called 'barking mad'!

  22. New Series: Science Communicators – Why We Love Communicating Science


    Continuing with your wish list, here are some people (again from the UK) who are better known as science communicators rather than as scientists...

    Simon Singh and John & Mary Gribben (and I suppose David Attenborough would fit more comfortably into this category)

    Had he not shuffled off this mortal coil, I would have added Nigel Calder to the list, as it would have been interesting to find out what drove him over to the dark side. I still have many of his books from around the time of my university days, and, leading up to 2005, he also authored Einstein's Universe as part of the annus mirabilis centennary celebrations.

    However, he somewhat blotted the old copybook by participating in the making of the film The Great Global Warming Swindle, and, along with Henrik Svensmark, co-authoring The Chilling Stars. (The latter being a truly hilarious read!)

    cheers     bill f

  23. There is no consensus


  24. Understanding adjustments to temperature data

    Comparing fig.1 (left) and trends on comment 12 it is clear that adjustment on the oceans during the first half of XX century has an opposite effect in comparison with adjustment on the lands.

    Curiously this shows that raw data for land between 1910 and 1980 are similar to adjusted data for land+ocean.  

  25. Understanding adjustments to temperature data

    Bill @36 - Since you're also from Devon you may well be interested in our latest exploration into the effects of the "sceptical MSM" on the psyches of a subset of the local population:

    Click a link or two and you will quickly discover how we're currently in the process of hauling both The Mail and The Telegraph in front of of the shiny new "Independent" Press Standards Organisation. However I wouldn't go so far as to say that I'm optimistic the process will ultimately produce an outcome along the lines that OPOF suggests, i.e. "a proper presentation of the actual facts of the matter [that] could be provided as an introduction to every misleading report".

    With a general election looming 38 Degrees are pretty active at the moment. What do you reckon to the idea of starting a petition against what Bob Ward of the Grantham Institute described as "A national scandal"?

  26. Models are unreliable

    Tom Curtis,

    That's a lot to think about. We'll see what happens with improved computers, better instruments and measurements.

  27. It's not bad

    Good working paper summarizing research on social cost of carbon (SCC). SCC is basically the amount of an optimal tax that would "internalize" the negative impacts of carbon, expressed as $ per ton of carbon emissions. See Havranek et al. 2014 CUDARE Working Papers #1139.  Correcting for publication bias, estimates of SCC are in the range $0 - $130 per tC, in 2010 USD for emission year 2015.  Still a lot of uncertainty, but still suggests that optimal policy involves a positive tax on carbon, as high as $130 per ton. 

  28. It's not bad

    Good article and comments on Tol's corrections at And Then There's Physics.

  29. It's not bad

    There is an update to Tol 2009.  See Jourrnal of Economic Perspectives 28(2): 221-26, Spring 2014. Update corrects errors in 2009 article and adds 5 new studies. Shows that GDP impact is negative for any increase in temperature anomaly. Previous paper showed positive impact up to 2degC anomaly. While Tol 2014 does not update estimate of optimal carbon tax, guessing it will be substantially higher than the original $45 per ton. 

  30. It's not bad

    @343-347 discussing the 2009 Tol research review of overall impact to humans of climate change, quantified in dollars. 

    This article needs to be part of the Further Reading associated with this argument. It reflects the state of economic knowledge about climate change impacts, published in the premier economics journal used to summarize research to date. To my knowledge the Tol research review hasn't been updated. 

    I am not sure if AR4 or AR5 incorporates this review or the studies it summarizes/synthesizes. If not would like to understand reasons for exclusion.  If so, the SKS write up needs to do a better job incorporating the research into this part of its site. The current write up doesn't fairly represent uncertainty that exists in the current science focused on quantifying net impacts of climate change. That said, the science still shows that rational decision makers should be willing to pay to reduce carbon emissions, which goes toward debunking the claim that we do not yet know enough to act. 

  31. New Series: Science Communicators – Why We Love Communicating Science

    Jim Hansen… altho he has done a pretty decent job on his own.
    Nicole Hernandez Hammer

    I wish I could name a few from the conservative side!

  32. With climate change, US presidents matter

    If you want to understand KXL, you had better understand what the corporate perspective is. As always, follow the money.

    The purpose of KXL was bring discounted dilbit to the Gulf Coast refiners for tax-free export of distillates. This exploits the massive crack spread between diesel/distillates and the tarsands "oil". The yield of distillates is as good as for WTI and lighter oil at a fraction of the price

    If you dig into the Valero 10-Q filings and investor presentations from 2010 or so you will see the plan spelled out in simple english.

    The real politics can be distilled down to this, the Kochs through Flint Hill Resources would pocket about 150,000 bbl x $15 a day exporting refined products compared to ~150,000 x $8 a day if the crude was transported by rail. Do the math, and then throw in that Warren Buffet (a known Democrat supporter) through Berkeshire Hathaway benefits if KXL is cancelled because his most recent purchase of BNSF would have increased rail traffic.

    Moderator Response:

    [JH] Your characteriztion of Warren Buffet's political role on the proposed Keystone XL appears to be incorrect. See: 

    Warren Buffett Backs Keystone XL, Says U.S. 'Thumbing Nose' At Canada by Alexander Panetta, The Canadian Press, Huff Post Canada, Mar 2, 2015

  33. New Series: Science Communicators – Why We Love Communicating Science

    Hi Collin,

    Thanks for this interesting piece, and good luck with the rest of the project.

    It would be fantastic to garner the views of people like Richard Feynman or Carl Sagan on the topic of deliberate disinformation, but communication from beyond the grave is still a tad on the unreliable side.

    Speaking with a UK bias, there are some candidates for your questionnaire that spring easily to mind...

    David Attenborough, Brian Cox, Jim al Khalili, Helen Czerski, Gabby Walker, Mark Miodownik, Marcus du Sautoy

    I'm sure there are many, many more, but I'm about to head off to muck out the donkeys.


    Cheers    Bill F

    PS Prof Brian Cox is the co-host on a BBC Radio 4 program called "The Infinite Monkey Cage". This involves some serious discussion on matters scientific, but with a large slice of satirical humour thrown in for good measure. It doesn't necessarily happen every time, but taking the piss out of climate change denial is part and parcel of the show's format. If you are unfamiliar with the show, it is worth trying to get hold of a podcast.

  34. Climatology versus Pseudoscience book tests whose predictions have been right

    It's my understanding that much of Arrhenius's high estimate was due to data limitations (spectroscopy - including the comb-like structure of GHG absorption/emissions), not to mention that the stratosphere had at that time not been discovered. 

    Barton Paul Levenson has an interesting graph from a few years ago that I've always found interesting, showing the progression of climate sensitivity estimates over the years - Arrhenius's estimate is the first point:

    B.P. Levenson - climate sensitivity estimates


    It seems pretty clear to me that multiple estimates over time, using multiple methods, have converged to something around 3C/doubling of CO2...

  35. Understanding adjustments to temperature data


    Final paragraph above should have started...

    "Few are going to have the cojones..."

  36. Understanding adjustments to temperature data

    @ Jim H & OPOF (#34 &35)

    " ... many of those people will never allow themselves to be convinced"

    Therein lies (pun intended) the rub. As most rational people will have long since realised, the so-called debate about global warming has nothing to do with science, or indeed with logical thought.

    Much of the MSM is owned, body and soul, by oligarchs with a special (i.e. financial) interest in the maintenance of the status quo. (This is an instance where it could be quite understandable to mistakenly render the word "oligarch" as "oiligarch"!) As this section of the MSM tends to be aimed squarely at right-leaning viewers, readers and - ultimately - voters, the whole climate change denial meme has become subsumed into the collective ring-wing mindset.

    I live in a small village next to Dartmoor National Park in the SW of England, and an overwhelming percentage of the populace are deeply conservative in their political opinions. The two best-selling newspapers at the local shop are - surprise, surprise - the Telegraph and the Mail.

    The problem I experience in trying to introduce some sanity into any debate about AGW is that it is well-nigh impossible. Why? Because any attempt to rebut the seemingly never-ending stream of drivel from the likes of Rose or Booker (or Monkton or WUWT, etc., etc.) is instantly perceived as an attack on intrinsic Tory values. Any attempt to illuminate the matter by introducing unwelcome and inconvenient concepts such as actual facts (as opposed to made-up or cherry-picked varieties) just gets shrugged off by those warmly cocooned in the smug arrogance engendered by never stopping to question one's own beliefs. 

    On a personal level, the situation down in sunny Devon is exacerbated by the fact that, despite having spent 40-odd years south of the border, I still have a very pronounced Glaswegian accent. There are people with very strong anti-AGW sentiments living here who would gladly scoop out their own eyeballs with a rusty spoon, rather than admit that some jumped-up Satan-spawn from Red Clydeside knows more about the topic than someone - upon whose every word they hang - writing in their paper of choice.

    However, leaving aside the parochial, the issue does actually run deeper. As mentioned before, this is not a genuine scientific disagreement over the interpretation of data. There are people in the MSM (and in many pseudo-science blogs) engaged in the dissemination of utter falsehoods. Eventually, they will stand trial at the bar of history - although personally, I'd much prefer that they stand trial in the conventional sense.

    Eventually, the guff emanating from the likes of Booker and Rose will be shown up for what it is, and, for many, it will be a truly bitter pill to swallow. People will have to accept the fact that their deeply held views were, not simply wrong, but utterly nonsensical - and that much of the MSM was knowingly complicit in perpetrating a fraud of truly biblical proportions. People will be forced to look themselves in the mirror, and admit that they were played as a fool*, and that they cheerfully went along with it for years. 

    (* Although the Scots term "eedjit" is a far more apt descriptor.)

    Few are going to have to cojones to admit this: many are just going to stuff their heads ever deeper in the sand. And as long as there are those prepared to buy their wares, the merchants of doubt will continue to spew forth their bile.


    And on that cheerful note...  awrabest    Bill F

  37. 2015 SkS News Bulletin #2: Willie Soon & The Fossil Fuel Industry

    Wiilie Soon's relationship with the fossil fuel industry while employed by the Smithsonian Institution at the Harvard-Smithsonian Center for Astrophysics.

    The Smithsonian policies are explicit: all fundings go the Insitute, not to individual scientists. Agreements are signed by its administration, not individual scienitsts. The Institue retains 40% of the grant amount for its administration.

  38. Climatology versus Pseudoscience book tests whose predictions have been right

    michael sweet @11 and sailrick @12, in 1896 Arrhenius worked out temperature increases for a variety of latitutudes from 70o North to 60o South.  The mean of the twelve values he determined is 5.5 C for a doubling of CO2, but that is not a global average.  The minimum value was 4.95 C at the equator.  Hence a global estimate would have been above 5 C, and probably greater than 5.5 C.  He later gave a figure of 5.7 C in a lecture in 1896.  By 1908 he had revised that down, but only to 4 C per doubling.   I cannot track any further revisions.

    Unfortunately it is not possible to turn these figures into a temperature prediction.  Because of thermal inertia, temperatures do not rise to the full Equilibrium Climate Response immediately.  As Arrhenius' values are for Equilbrium Climate Sensitivity rather than the Transient Climate Response, to convert them into a prediction by Arrhenius you would need a value from Arrhenius for the thermal inertia, which is, SFAIK, lacking.

  39. Models are unreliable

    protagorias @various, of course climate modellers want to make their models more accurate.  The problem is that you and they have different conceptions as to what is involved.  There are several key issues on this.

    First, short term variations in climate are chaotic.  This is best illustrated by the essentially random pattern of ENSO fluctuations - one that means that though a climate model may model such fluctuations, the probability that it models the timeing and strengths of particular El Ninos and La Ninas is minimal.  Consequently, accuracy in a climate model does not mean exactly mimicing the year to year variation in temperature.  Strictly it means that the statistics of multiple runs of the model match the statistics of multiple runs of the Earth climate system.  Unfortunately, the universe has not been generous enough to give us multiple runs of the Earth climate system.  We have to settle with just one, which may be statisticaly unusual relative to a hypothetical multi-system mean.  That means in turn that altering a model to better fit a trend, particularly a short term trend may in fact make it less accurate.  The problem is accentuated in that for most models we only have a very few runs (and for none do we have sufficient runs to properly quantify ensemble means for that model).  Therefore the model run you are altering may also be statistically unusual.  Indeed, raw statistics suggests that the Earth's realized climate history must be statistically unusual in some way relative to a hypothetical system ensemble mean (but hopefully not too much), and the same for any realized run for a given model relative to its hypothetical model mean.

    Given this situation, they way you make models better is to compare the Earth's realized climate history to the multi-model ensemble mean; but assume only that that realized history is close to statistically normal.  You do not sweat small differences, because small differences are as likely to be statistical aberrations as model errors.  Instead you progressively improve the match between model physics and real world physics; and map which features of models lead to which differences with reality so as you get more data you get a better idea of what needs changing.

    Ideally we would have research programs in which this was done independently for each model.  That, however, would require research budgets sufficient to allow each model to be run multiple times (around 100) per year, ie, it would require a ten fold increase in funding (or thereabouts).  It would also require persuading the modellers that their best gain in accuracy would be in getting better model statistics rather than using that extra computer power to get better resolution.  At the moment they think otherwise, and they are far better informed on the topic than you or I, so I would not try to dissuade them.  As computer time rises with the fourth power of resolution, however, eventually the greater gain will be found with better ensemble statistics.

    Finally, in this I have glossed over the other big problem climate modellers face - the climate is very complex.  Most criticisms of models focus entirely on temperature, often just GMST.  However, an alteration that improves predictions of temperature may make predictions of precipitation, or windspeeds, or any of a large number of other variables, worse.  It then becomes unclear what is, or is not an improvement.  The solution is the same as the solution for the chaotic nature of wheather.  However, these too factors combined mean that one sure way to end the progressive improvement of climate models is to start chasing a close match to GMST trends in the interests of "accuracy".  Such improvements will happen as a result of the current program, and are desirable - but chasing it directly means either tracking spurious short term trends, or introducing fudges that will worsten performance in other areas.

  40. Climatology versus Pseudoscience book tests whose predictions have been right

    michael sweet     

     I'm pretty sure I read that Arhennius recalculated climate sensitivity later on and came up with more like 2.5 C  which is even closer to the  IPCC most likely 3 C 

  41. One Planet Only Forever at 12:18 PM on 3 March 2015
    Understanding adjustments to temperature data


    I agree with Jim Hunt's summation that you have been identifying the unacceptable behaviour in the MSM reporting regarding climate science. Unlike Jim, who asks what you believe climate scientists should do, I would ask why you expect that your comments here will change the unacceptable behaviour in the MSM that you are aware of.

    The people who contribute to this site or frequently visits this site are probably well aware of the unacceptable behaviour of many reporters/opinion makers in the MSM as well as at other misleading sites. And it would be wonderful if a proper presentation of the actual facts of the matter could be provided as an introduction to every misleading report in the first posting of the misleading report, but that won't happen.

    What can happen is the continued development of the best understanding of what is going on, not just the climate science, but also what is going on in the presentation of information to the public and how people who claim to be 'leaders' have actually been behaving. That is what this site, and many like it are all about.

    Eventually the majority of the population will stop believing the misleading claim-making and the fraudulent 'leaders', realizing who the real trouble-makers are. That is the only future for humanity and that effective majority realization is already here (even in the Canada, USA, and Australia), but the trouble-makers are still able to deceptively maintain undeserved wealth accummulation and power (and abusive misleading marketing influence). However, their days are clearly as limited as the unsustainable damaging pursuits they strive to prolong with the small pool of support from people who can never be expected to give up their fight to get away with undeserved unsustainable and damaging desired actions.

    'Every man on the street' does not need to be convinced. In fact, many of those people will never allow themselves to be convinced. The developing better understanding and progress of humanity toward a sustainable better futre for all will leave them bitterly disappointed, as they deserve to be, with their only real choice being to 'change their mind'. And the continued pursuit of the best understanding of what is going on is the key to making that happen.

  42. Models are unreliable


    You're right. I hadn't even noticed that! I tend to make wild leaps sometimes, i apologize for that.

  43. Models are unreliable

    Protagorias, I suggest you actually read the articles you link to.  That insurance one is about insurance models.  It has nothing to do with GCMs.

  44. Understanding adjustments to temperature data

    Ryland @30 - So we're agreed that the "sceptical MSM" just make stuff up that they think their audience would like to hear? That being the case, what should climate scientists do about that situation. Start making stuff up as well? Failing that, how should they alter their communications such that they start to "resonate with the man in the street"?

  45. Models are unreliable

    Yet that is precisely what is relevant. Why else would climate modellers be asking for better software from which to better model climate change, if they didn't have, or at least recognize, the need for better input?

    Please note this recent article in the Insurance Journal. Climate Change Modelling on Cusp of Paradigm Shift


    Silicon Valley-based modeler Risk Management Solutions last year partnered on the Risky Business initiative, a year-long effort co-chaired by former New York Mayor Michael Bloomberg, former Treasury Secretary Henry Paulson, and Farallon Capital founder Tom Steyer, to quantify and publicize the economic risks the U.S. faces from the impacts of a changing climate.

    For the initiative RMS provided an analysis of the impacts that climate change will likely have on coastal infrastructure and related assets. Risky Business issued a report late last year focused on the clearest and most economically significant risks: “Damage to coastal property and infrastructure from rising sea levels and increased storm surge, climate-driven changes in agricultural production and energy demand, and the impact of higher temperatures on labor productivity and public health.”

    Paul Wilson, vice president of model development for RMS and leader of the firm’s North Atlantic hurricane modeling team, said clients are often asking the same question: “How much variability can we expect?”

    “That’s a conversation RMS has very regularly with our clients,” Wilson said. “We need to think about to what degree climate change is impacting that variability, to what degree is climate change impacting that baseline around which we build our models.”

    In response to these conversations, RMS will be incorporating more variability into more models in future, although it’s the overall concern over variability, and not necessarily climate change, that may be driving some of that interest, he added.

  46. 2015 SkS Weekly Digest #9


    Where does the sentence on Leonard's picture come from. Did Leonard say it and on what occasion? Can you provide the source?

    While we are remembering his life I want to know more about him and want to know in detail why he's featured here in SkS. Thanks!

    Moderator Response:

    [JH] Many members of the all-volunteer SkS author team are fans of Star Trek.  Mr. Spock embodies the concept of logical thinking which underpins science. The poster is from the album section of the "I Heart Scientist's" Facebook page. 

  47. Models are unreliable

    Only one quick example

    International Journal of Climatology Vol 25, Issue 15 High Resolution Climate Surfaces for Global Land Areas

     For many applications, data at a fine spatial resolution are necessary to capture environmental variability that can be partly lost at lower resolutions, particularly in mountainous or other areas with steep climate gradients. However, such high-resolution data are only available for certain parts of the world...


    Moderator Response:

    [PS] Except that it is not. What is discussed is not input into any GCM.

  48. Understanding adjustments to temperature data

    Sorry, that last post should have said "_fewer_" skeptics on talk shows.

  49. New Video: What Climate Deniers Learned from Big Tobacco

    Thanks guys,  for the correction.  I marched off to take my wife to the opera before proofing my comment.  

  50. Understanding adjustments to temperature data

    ryland - Fortunately, with the exception of the usual suspects (Fox News, The Telegraph, the Australian, and so on), mainstream media appears to be taking climate change much more seriously.. Skeptics on talk shows, dimension of climate change comes more and more often in general news shows, etc.

    It's my impression that the deniers are just becoming less and less credible. 

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