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The climate has always changed. What do you conclude?

Filed under: — stefan @ 20 July 2017

Probably everyone has heard this argument, presented as objection against the findings of climate scientists on global warming: “The climate has always changed!” And it is true: climate has changed even before humans began to burn fossil fuels. So what can we conclude from that?

A quick quiz

Do you conclude…

(1) that humans cannot change the climate?

(2) that we do not know whether humans are to blame for global warming?

(3) that global warming will not have any severe consequences?

(4) that we cannot stop global warming?

The answer

Not one of these answers is correct. None of these conclusions would be logical. Why not?

(1) The opposite conclusion is correct: if the climate had hardly changed during the course of the Earth’s history (despite variable incoming solar radiation and changing amounts of CO2 in the atmosphere), then we would conclude that there are strong stabilizing feedbacks in the climate system. The drastic climate changes in the history of the Earth (ice ages, hot ice-free periods) show that the climate system is sensitive to changes in the radiation budget. The measure for this sensitivity is called climate sensitivity: how much global warming will result from a CO2 doubling in the air? For the first time it was estimated by the Nobel laureate Svante Arrhenius in 1896. According to our modern knowledge this climate sensitivity is around 3°C (uncertainty ± 1°C).

Paleoclimatologists determine the climate sensitivity from data from the Earth’s history. A recent review article in Nature on this method showed “a warming around 2.2 to 4.8 °C per doubling of atmospheric CO2, which agrees with IPCC estimates”. In short: the larger past natural climate changes have been, the more vulnerable is the climate system, and the more it will react to the greenhouse gases that humans are adding to the system.

(2) Imagine there has been a forest fire. The police have extensive evidence that it was arson. They know the place where the fire began. They found traces of fire accelerants. Witnesses observed a man whose car was parked nearby. In his trunk the police finds bottles with fire accelerants, and in his house they find even more of it. He has been convicted for arson several times before. Plus some further evidence. In court, he defends himself: forest fires have always occurred lit by lightning, even before there was any man on Earth. Therefore he must be innocent. Does the argument convince you?

The evidence for the human cause of global warming is overwhelming. This is why there has been a consensus among climate researchers for a long time, and almost every scientific academy on the planet has come to the same conclusion. The most important evidence: when it gets warmer, the energy has to come from somewhere (1st law of thermodynamics). It can only come through the radiation budget of our planet. (No, Rick Perry, the energy does not come out of the ocean. To the contrary, measurements show heat is going into the oceans). The changes in this energy balance are quite well known and are shown near the front of any IPCC report – see Fig. 1. The biggest factor is the increase in CO2 concentration as well as a few other greenhouse gases, also added by human activities. The incoming solar radiation has changed just a tiny bit in comparison – since 1950, by the way, it has even decreased and thus offset a small part of the human-caused warming – hence humans have probably caused more warming than is observed (best estimate is 110% of observed warming).

Fig. 1 Radiative forcing is the cause of global temperature changes. Red bars show warming, blue bars cooling effects. I am showing the diagram from the fourth IPCC report of 2007, because it is easier to understand than the more recent from the 5th IPCC Report of 2013, which Gavin discussed here. The overall human-caused radiative forcing, which is given here as 1.6 watts per square meter, had already risen to 2.3 watts per square meter by the year 2011 according to the 5th IPCC report. Source: IPCC report 4 Fig. SPM.2.

Overall, humans have caused an additional heating (radiative forcing) of 2.3 watts per square meter of Earth surface – as of 2011. It has increased further since.

(3) Those who can’t deny that humans are causing warming often seek refuge in the hope that the consequences might not be so bad, so we might just adapt rather than having to stop further warming. The climatic changes in Earth’s history do not support this point of view. As a result of the global warming by around 5 ° C from the last ice age 15,000 years ago to the mid-Holocene, global sea levels rose by 120 meters until 5,000 years ago! At that time hardly a problem – but for today’s humankind even a rise of two meters would be a disaster, bringing devastation to coastal cities and small island states. We still have enough ice on Greenland and Antarctica to raise the sea level around the world by 65 meters. Both ice masses are losing ice more and more quickly. The West Antarctic has probably already crossed its tipping point and is unstable. Greenland could soon follow.

Fig. 2 Ice loss of Greenland measured by GRACE satellites. Source: NASA .

By the way: the just mentioned 5°C rise within ten thousand years at the end of the ice age are among the fastest global temperature rises documented in the Earth’s history. That is 0.05 degrees per century. In the last hundred years we have caused the twentyfold rise. This pace of change overtaxes the adaptability of many ecosystems and will lead to their collapse as the warming progresses. In coral reefs this is already in progress.

The pace of the completely man-made CO2 increase (by now the CO2 concentration is higher than at any time in the past three million years) leads to a rapid acidification of the world’s oceans, because it overcomes the buffer capacity of the oceans. The last major acidification event 250 million years ago has apparently led to a massive extinction of species in the world’s oceans.

(4) Often I hear that the aims of the Paris Climate Agreement are absurd, because humans cannot stabilize the global temperature – after all, our climate changes even without human intervention. This argument is also wrong. As already mentioned, without human interference there would have been no global warming since the middle of the 20th century. If anything there would have been a slight natural cooling. The fluctuations in the sun’s activity are causing variations of 0.1 or 0.2 °C in global temperature in the last thousand years (e.g. at the Maunder Minimum of solar activity in the years 1645 to 1715). In the longer term, the astronomical Milankovitch cycles of the Earth’s orbit and the Earth’s axis dominate the natural climate changes (hence the ice ages). The shortest of these cycles has a period of 23,000 years – for the next hundred years, it practically does not matter. However, our fortune would last much longer than that: the Milankovitch cycles can be calculated over millions of years with astronomical precision (and incidentally be used to predict the beginning of all the past ice ages), and according to that, the next major climate change would arrive only in about 50,000 years. Namely the next ice age.

So if we weren’t doing something really stupid, we could benefit from another 50,000 years with a stable climate. Nothing in our knowledge of paleoclimatology suggests that natural factors could prevent us from limiting global warming to below 2°C. Only our own dithering, our own inertia can do that. Or that we prefer to be lulled into fatal complacency by the reassuring fairy tales of the “climate skeptics” rather than confronting the danger.

Among the most ill-informed claims of those “skeptics” is the assertion that climate researchers do not know or consciously ignore the fact that the climate has always changed. Utter nonsense, of course. Almost all of the authors here at Realclimate have done substantial work in paleoclimate for decades, as you can see from our publication lists (including the textbook Paleoclimatology). A lot of other climate researchers do the same. This May, three of us were at a conference of almost one thousand paleoclimatologists in Zaragoza (see photo below). These researchers know more about the natural, past climate changes than anyone else. Nobody there expressed any doubts about the ongoing human-caused global warming. On the contrary, many paleoclimatologists are particularly concerned about anthropogenic warming, especially in view of our findings about Earth’s history. Already when I was working as lead author on the paleoclimate chapter of the 4th IPCC report more than a decade ago, some of the discussions within IPCC revolved around us paleoclimatologists regarding some risks as considerably more serious than the colleagues specializing in the modern climate, such as the risk of rapid sea level rise or instability of ocean currents and ice sheets.

Whoever tells you that the fact that “the climate has always changed” is somehow reassuring, does not know what he is talking about – or he is trying to con you.

Paleoclimatologists: participants in the PAGES Open Science Meeting in Zaragoza in May 2017

 

243 Responses to “The climate has always changed. What do you conclude?”

  1. 151
    Victor says:

    “Dire idiots like Victor the Troll have no place here making bold statements about something they can have little or no understanding of, no place outside the borehole.”

    Aw, shucks, Mr. Rodger. I’ll bet you say that to all the trolls.

  2. 152
    Donna says:

    Its sort of ironic – the question about how the climate has always changed and how do we know that human activity is causing it and why what we see now is different than in the past was for me an opening to want to learn, to want to understand what we were finding out about climate and human activity and a whole bunch of other stuff.
    So this pseudo-argument used by those who do not want to learn or to understand was for me a springboard into a fascinating part of science I had not thought that much about before.
    I knew some parts of the argument (for instance humans were not responsible in the past or humans can’t be responsible for changes on planets where there are not humans) were just silly but the “how do we know”, what evidence supports and what are we still learning about discussions were very interesting.
    So instead of the argument being one which might have turned me into a ‘denier’, it turned me into someone who understood at least a bit more and supported the work of those studying the system and the conclusions that they have made.

  3. 153
    Ray Ladbury says:

    Weaktor: “The author’s bias is all too clear, so everything he writes has to be taken with a huge grain of salt.”

    Ooh! Classic ad hominem attack. I have Bingo on my denialist bingo card!

    Weaktor: “No, not at all. The skeptical argument is based, very simply, on the failure of certain climate scientists to offer convincing evidence supporting their theories on the inability of so-called skeptics to understand what constitutes evidence.”

    There, fixed it for you

  4. 154
    CCHolley says:

    As far as those “forcings” are concerned, the fact that the climate has changed many times in the past for reasons either unknown or not well understood, should be enough. If climate changed in the past for reasons unknown, then it might well be changing now for reasons unknown. Just as temperatures went down in the 40’s for reasons unknown, leading to speculation about a coming ice age.

    Of course this is totally misleading. There really are no unknown reasons for climate changes. Long term temperature trends must be due to a change in the energy balance. The radiative forcings that can cause such changes are well identified. This is basic physics. Shorter term natural unforced variations are simply the result of redistribution of heat within the climate system and are limited in total effect on temperatures. The 1940s example of *reasons unknown* is bogus. The most likely change in forcing resulting in cooling was an increase in aerosols due to both a rapid increase in industrialization and increased volcanic activity. There is strong evidence for this. I know of no period of climate change for reasons unknown. All are explainable within our knowledge of how climate works.

  5. 155
    CCHolley says:

    Victor @145

    As far as those “forcings” are concerned, the fact that the climate has changed many times in the past for reasons either unknown or not well understood, should be enough. If climate changed in the past for reasons unknown, then it might well be changing now for reasons unknown. Just as temperatures went down in the 40’s for reasons unknown, leading to speculation about a coming ice age.

    Of course this is totally misleading. There really are no unknown reasons for climate changes. Long term temperature trends must be due to a change in the energy balance. This is basic physics. The radiative forcings that can cause such changes are well identified. Shorter term natural unforced variations are simply the result of redistribution of heat within the climate system and are limited in total effect on temperatures–less than the current observed. The 1940s example of *reasons unknown* is bogus. The most likely change in forcing resulting in cooling was an increase in aerosols due to both a rapid increase in industrialization and increased volcanic activity. There is strong evidence for this. I know of no period of climate change that were for reasons totally unknown. All are explainable within our knowledge of how climate works.

  6. 156
    Steven Emmerson says:

    Bob Loblaw @ 140

    I understand that solar irradiance is outside the atmosphere. This is why I was surprised at its level of uncertainty given the existence of satellites.

    Is the baseline for the forcings plot pre-satellite so that the uncertainty reflects the ground-based measurements of the time or is the satellite-based measurement of solar irradiance that uncertain?

    [Response: It’s the time history prior to the 1970s, particularly how the ‘background’ activity may have changed. There are proxies one can use but the link to the processes and the satellite data are trickier. – gavin]

  7. 157
    Hank Roberts says:

    Victor says: 20 Jul 2017 at 11:26 AM

    … When examining the many graphs depicting the history of worldwide temperatures over the 20th and 21st centuries, I see no evidence …

  8. 158
    Hank Roberts says:

    When examining the many posts by Victor, I see no evidence he understands why statistics was developed.
    pareidolia

  9. 159
    Thomas says:

    Explorations of (absent) self-insight among the incompetent
    http://www.sciencedirect.com/science/article/pii/S074959780700060X

    Lots of graphs and data here for Victor to ‘analyze’ for their scientific rigour and critical thinking or lack thereof:
    Refs http://www.columbia.edu/~jeh1/mailings/2017/20170718_BurdenCommunication.pdf

    Received: 22 Sep 2016 – Discussion started: 04 Oct 2016 Revised: 29 May 2017 – Accepted: 08 Jun 2017 – Published: 18 Jul 2017 – Abstract https://www.earth-syst-dynam.net/8/577/2017/esd-8-577-2017.html

    Paper in full https://www.earth-syst-dynam.net/8/577/2017/esd-8-577-2017.pdf

    Or better still, Mount Stupid should ‘analyse’ these Papers for ‘critical thinking skill’ and ‘logic’ and ‘evidence’ and ‘cognitive bias’???
    https://scholar.google.com.au/scholar?hl=en&as_sdt=0,5&q=dunning+kruger+effect

    http://rationalwiki.org/wiki/Dunning-Kruger_effect

    (sigh)

  10. 160
    Brian Dodge says:

    Victor

    https://curryja.files.wordpress.com/2015/11/slide05.png

    http://www.woodfortrees.org/plot/gistemp/from:1930/scale:110/offset:310/mean:12/plot/esrl-co2/plot/gistemp/from:1937/to:1970/scale:110/offset:310/trend/plot/gistemp/from:1970/scale:110/offset:310/trend/plot/gistemp/from:1992/scale:110/offset:310/trend

    You will note from the first graph that there was a flattening of the rise in CO2 from ~1930 to ~1950, which “correlates” with a delayed decrease in temperature between ~1937 and ~1977.
    about 20 years after CO2 starts rising again ~1950, the rise in temperature resumes. As the rise in CO2 accelerates, the rise in temperature accelerates. The correlation coefficient for monthly CO2 versus temperature
    is 0.886. If one takes a 12 month running average to remove noise before calculation the correlation, it rises to 0.948.

  11. 161
    alphagruis says:

    BPL (#142°

    That’s why God made energy storage and wide-area smart grids. BTW, neither fossil fuels nor nuclear is 24/7, either.

    Excellent joke !
    Triggers screaming laughters at the coffee machine.

    Cheers from alpha crux

  12. 162
    Susan Anderson says:

    Donna @~152.

    Hallelujah! All praise and thanks from someone who hopes she is your sister in curiosity!

  13. 163
    Victor says:

    #159. Greetings, Thomas. So, once again with the “Dunning-Kruger” effect, otherwise known as “what you accuse anyone of who challenges your high opinion of yourself.” The problem with this move is that the effect just might apply to you rather than the object of your derision.

    I am the author of several peer reviewed papers in leading journals of semiotics, anthropology, theory of the arts, film theory and musicology. I have held teaching positions at leading, fully accredited universities and other institutions of higher learning. I hold a Masters degree from Wesleyan University and and Ph.D. from SUNY Buffalo. Creative works of mine have been presented at institutions such as The Whitney Museum of American Art, the Carnegie Museum of Art, the Albright-Knox Gallery, the Barbicon Center, Lincoln Center and, most recently, the National Gallery.

    And yes, I have engaged in statistics-based research over many years, working closely with top professionals in this field, none of whom has ever questioned my competence.

    What are YOUR credentials, if I may ask?

  14. 164
    Victor says:

    #160 Brian Dodge. Well, finally a response with some actual science in it. How refreshing, thank you.

    I’ve never seen that particular graph of CO2 levels, nor have I noticed any flattening before, so yes, that graph is interesting. Here’s another graph, from Skeptical Science, where CO2 levels and temp. are superimposed: https://static.skepticalscience.com/images/co2_temp_1900_2008.gif

    I see a similar flattening of CO2 levels, from roughly the mid-30s to 1950. Compare, however, with the precipitous drop in temperatures from ca. 1945 to 1950, as clearly visible on that same graph. It’s hard for me to imagine how a flatting of CO2 levels could lead to such an extreme drop of global temperatures, a drop that seems to have persisted into the mid 60s. And I don’t see any consistent rise until ca. 1979. From that year to 1998 there is, of course, a very steep rise, comparable to the rise between 1910 and 1945 (according to this graph, which is a bit different from others I’ve seen). And again, I find it hard to attribute this rise to a resumption of the rise in CO2 from an essentially flat period.

    As I’m sure you know, the rapid cooling after the 1940s has been attributed to the heavy industrialization that began during that era, which would have sent increasing amounts of aerosols from burning coal into the atmosphere to interfere with solar radiation. But the leveling you’ve pointed to seems inconsistent with that idea, as the burning coal should have greatly increased CO2 levels during that time. Apparently it did not. And if it did not, then the amount of aerosol pollution would have remained more or less the same as well, no?

    I’m also bothered by a theory that attributes cooling to the emission of aerosols and warming to the emission of CO2, both stemming from the same increase in industrialization and indeed from the same coal burning plants. Can you really have it BOTH ways?

    Anyhow, thanks for the interesting heads up.

  15. 165
    nigelj says:

    Alphagrius @150

    “Even coal would be clean if one had to power a 70 millions people civilization ! A hundred times less CO2 emissions and there is no sizable effect to be expected on climate anymore. Same for mercury, sulphur and other “pollutants”.”

    This is another strawman regarding CO2 emissions, because we obviously aren’t looking at some civilisation at that level of use. And even for 70 million, particulate emissions would still obviously be bad for the health of those 70 million.

    “Coal is a problem for a 7 billions people civilization but so are most likely intermittent solar and wind and even hydro. The former need storage capacity and a lot of mining (thanks to fossil fuels, by the way !) to get the huge amounts of (usually toxic) metals,”

    I have already explained if you have a civilisation for example based on predominantly wind power, there are several ways of dealing with wind intermittency. Battery type storage is only one option.The toxic metals involved are still easier to control and contain than burning coal.

    Alternatively you have widely dispersed wind power geographically, and provide a surplus of wind power overall to cope with days where the wind isn’t blowing in one part of the country, and shift the power around with smart grids. This is already done to some extent. Calculations have shown you don’t need a particularly large surplus.

    Alternatively you use electricity from wind or solar power to power hydro storage, so avoiding your concerns about toxic metals.

    “If it doesn’t come “cheap” enough it won’t be done.”

    This is simply not the case. Governments can and do force these things with regulations and / or subsidies.

    However renewable energy has dropped a lot in price ahead of expectations so is economically competitive in many cases, without needing subsidies or regulatory forcing, or cap and trade type systems.

    “And everybody, New Zealand and Iceland included, still imports large amounts of fossil fuels for transport, agriculture”

    Yes thanks for the history lesson, but this is slowly changing and can change if we collectively want it to change. Obviously you don’t want it to change.

    “And what about Africa, such as Cameroun,”

    As you say they lack capital but that is a problem for all forms of electricity especially costly centralised plans. In fact their best option may be a dispersed grid of local solar power in terms of cost and practicality, even if it doesn’t provide 24 / 7 power.

    Like I said the large Study by Jacobson looked at all countries including Africa and the suggested balance of generation in each country. You can google the research easily enough. The Link below is just a brief overview.

    http://thesolutionsproject.org/why-clean-energy/

  16. 166
    nigelj says:

    Thomas @159, the research looks interesting enough, a further exploration of the Dunning kruger effect.

    I think something else also happens, observation and speculation on my part. One of my best friends at school was great in history, languages etc, even the complexities of philosophy, but terrible at maths and science. I have seen other people who are just the opposite. It’s like the brains of some people can process complex language but not physical cause and effect. Its not that his maths was totally bad on everyday tasks. Of course other people are well rounded in most subjects.

    But the point is people may be reasonably intelligent, and do well in some area (maybe property development, thinking of a certain politician, or Victor) and assume it means they have expertise or good judgement on everything. Sadly it’s these very same people who are weak in science that also seem to lack insight into their limitations, probably because as they are weak in science, that are lacking in natural critical analysis skills on how their own mind works. They get through life well in a business sense, on the basis of passably reasonable intelligence, drive, supreme self confidence, personality, focus and multi tasking but often have no understanding at all of science, economic theory etc and possibly never will have.

  17. 167
    Brian Dodge says:

    solar cycle variance min to max approx=(1366.6-1365.25)/((1388.6+1365.25)/2)
    ~ 0.10% (Eyeballed from satellite TSI at http://www.woodfortrees.org/plot/pmod/from:1937/mean:12 )

    TSI = 342W/m^2 (Trenberth energy balance diagram)
    uncertainty = 0.3-0.06 = 0.24 (Figure 1 column 3)
    percent = 0.24/342 = 0.07%

    I wouldn’t call that surprising.

    “The Hatch-Waxman Act allows a much wider range of variation than that. It allows between 80 percent and 125 percent of the concentration of the drugs in blood plasma over time of tested patients as compared with the innovator for it to be deemed bioequivalent and hence be approved and receive a registration for use in the US.” http://safemedicinescoalition.org/resources/wp_drug_inequality.pdf

  18. 168
    alphagruis says:

    Thomas (#159)

    Psychology is not yet a science.
    And there is not even the least consensus among the relevant “pseudoscientists” ( that would of course not prove much more by the way).

  19. 169
    AntonyIndia says:

    My main problem stays that the total net antropogenic radiative forcing still is not narrowed down (error bar: 0.6 to 2.4 or 400% difference – see figure 1 bottom) after zillions of hours study.
    How can anyone advocate a fast & radical change of the complete world economy based on that much uncertainty?
    Reducing fossil fuel usage to limit NOx and PM 2.5 health hazards or to de-fang oil fuelled Islamism are 2 much surer reasons to get people on board – but not on a break neck speed train.

  20. 170
    Andrew says:

    A quick reminder to all: please don’t feed the troll(s).

  21. 171
    Thomas says:

    It’s my personal bug-bear, about effective communication / story / narrative understanding about the truth/s og agw/cc vs bs …. apparently even Al Gore and thousands of professional academics, psychologists, marketing experts, economists, psychologists and cognitive scientists, various ‘leaders’, activists and climate scientists happen to agree with this missing ingredient .

    “[..] what Gore’s work has shown and continues to show is that evidence is not enough.”
    https://www.theguardian.com/us-news/2017/jul/30/al-gore-interview-our-crumbling-planet-the-rich-have-subverted-all-reason-al-gore

    Yet the predominating evidence/reality keeps telling me that nothing is going to change, nothing about agw/cc looming impacts 1 yr to 20yrs to 50 years is going to be solved either. That’s my genuine opinion fwiw. One of zero confidence in any current “human effort” will occur and zero hope there’s anything on the decadal horizon either.

    Despite the kinds of ‘logical long term solutions’ be patently obvious already. My cheery comment for the day with a (smile) and a (shrug)

  22. 172
    alphagruis says:

    Nigelj (#165)

    “If it doesn’t come “cheap” enough it won’t be done.”

    This is simply not the case. Governments can and do force these things with regulations and / or subsidies.

    As I told you, that’s just wishful thinking.

    Like I said the large Study by Jacobson looked at all countries including Africa and the suggested balance of generation in each country. You can google the research easily enough.

    Done as soon as it’s been published !
    But, by the way, why don’t you google a critical review of all this “research” ?
    Just from abstract some food for thought:
    “We find that all of the scenarios envision historically unprecedented improvements in energy intensity…”
    “… all of the studies present comparatively little detail on strategies to decarbonize the industrial and transportation sectors, and most give superficial treatment to relevant constraints on energy system transformations.”

    “And everybody, New Zealand and Iceland included, still imports large amounts of fossil fuels for transport, agriculture”

    Yes thanks for the history lesson, but this is slowly changing and can change if we collectively want it to change. Obviously you don’t want it to change.

    Obviously ?
    Amazing.
    At any rate what I (or you) want or don’t want is quite irrelevant. Reality is very stubborn.

    In spite of of all the hydro, geothermal and wind in NZ there is still a long way to go.

  23. 173

    BPL: That’s why God made energy storage and wide-area smart grids. BTW, neither fossil fuels nor nuclear is 24/7, either.

    Alnair: Excellent joke !
    Triggers screaming laughters at the coffee machine.
    Cheers from alpha crux

    BPL: Solar thermal plants in California have already made better on-line time than neighboring coal-fired plants. Laughter may be easier than argument, but it’s less convincing.

  24. 174

    V 163: I am the author of several peer reviewed papers in leading journals of semiotics, anthropology, theory of the arts, film theory and musicology.

    BPL: None of which make you competent in planetary astronomy or climatology. William Shockley was a great physicist, but when he promoted hereditarian views on race and IQ, he made a fool of himself. Expertise in one field never automatically grants expertise in another.

  25. 175
    nigelj says:

    Alphagrius @168, psychology is a social science, in the same category group as sociology, anthropology, economics, etc. I wouldn’t be quite so dismissive of it. With psychology, some of the theories, understandings and tools are very robust, much is not yet known or well understood. Modelling human behaviour is not easy, but that doesn’t mean we know nothing. (now ain’t that rather like the climate)

    Thomas @171, good article by the Guardian on Gore,etc. Sums the state of play up rather well.

  26. 176
    MA Rodger says:

    Brian Dodge @160,
    I was intrigued by the graphic you linked to and was wondering what Judy Curry would have been using it for on her asteroid “Climateetc.” It turned out to be her usual desperate nonsense of trying to get just a tiny bit of credibilty for her bold assertions about late twentieth century warming having a significant portion of natural assistance but (assuming she meant “its difficult to ignore” ‘if you are a climate denier.’) I did notice her comment contained something interesting:-

    “And while you are considering the above figure, check out the ‘hiatus’ in CO2 increase that occurred 1940-1960; its difficult to ignore that this could be driven by the grand hiatus in warming. (Note: Ralph Keeling was very interested in this feature).


    What took my interest here was Judy’s reference to Ralph Keeling but this proved to be the usual error-filled Judy nonsense. Firstly it is father Charles Keeling she is actually referring to and secondly there is no evidence that Charles Keeling was ever “interested” in the 1940s CO2 “hiatus”. Judy’s quote from Charles Keeling come from this lengthy 1998 article which has a final chapter describing some speculations resulting from having seen “decadal” variation in both MLO CO2 and in global temperature. (Of course, Keeling should have done better extracting the ENSO signal from the data prior to this “decadal” analysis as all he is showing with his “decadal” data is a smoothed-out ENSO which Keeling had already demonstrated impacts both CO2 and temperature. Note he nowhere uses pre-1958 CO2 data.) The speculations are little more than speculative curve-fitting and if there had been more to it, it would have been actually reinforcing the absence of a natural warming component within late twentieth century warming. Had Judy managed to grasp that Keeling’s speculation contradicted her own speculations, she may have been less eager to name-drop the wrong name.

    As for the 1940s CO2 ‘hiatus’, as AR5 Fig 8.6d shows, it does greatly reduce the additional total positive anthropogenic forcings for that decade and thus would be a driver (one of many) for Judy’s “grand hiatus in warming” and not “driven” by it as poor yduJ manages to make it. The strange atmosphere on her asteroid “Climateetc” is evidently not conducive to thinking things out the right-way-round.

  27. 177
    Karl Anderson says:

    AntonyIndia:

    How can anyone advocate a fast & radical change of the complete world economy based on that much uncertainty?

    I’ll respond from the PoV of a US voter:

    1. What ‘breakneck speed train’? Who is advocating a ‘fast and radical change in the complete world economy’? Carbon Fee and Dividend with Border Adjustment Tariff is just a tax like the ones we all pay already, except that everybody periodically gets an equal share of the revenue back. Net cost is $0.

    2. Uncertainty is not our friend. Actual net anthropogenic forcing could just as easily be at the upper end of the range as well as the lower. Play the odds, not your hopes.

  28. 178
    Ray Ladbury says:

    Victor: “Can you really have it BOTH ways?”

    Now this is just sad. Weaktor, dude, we’re talking about two different effects originating from the same cause.

    You are a perfect example of what stupidity looks like when it gets sent to college.

  29. 179
    Thomas says:

    163 Victor: “What are YOUR credentials, if I may ask?”

    You may ask whatever you wish Victor. It’s a free world. I’ll offer up 3 simple ones for starters, while keeping it simple.

    1) I know what a distracting fallacious appeal to authority looks like when I see it. Maybe you missed my NPD missive? :-)
    2) I know exactly what the following commenters are saying/mean/intend; and where they are coming from @ 152, 153, 154, 160, 162, and 174.
    3) I know my limitations.

    When you can top that please get back to me. :-)

  30. 180
    Victor says:

    #174:

    V 163: I am the author of several peer reviewed papers in leading journals of semiotics, anthropology, theory of the arts, film theory and musicology.

    BPL: None of which make you competent in planetary astronomy or climatology. William Shockley was a great physicist, but when he promoted hereditarian views on race and IQ, he made a fool of himself. Expertise in one field never automatically grants expertise in another.

    I’ve never claimed competence in any field pertaining to climatology, nor, unlike so many posting here, do I see myself as any sort of “expert.” However, if I were the sort of “idiot” I’m continually accused of being, I doubt I’d have gotten very far in the academic and artistic arenas in which I’ve been active for so many years. And yes, I’ve also been active as a scientist, as I’ve already indicated, though in the social rather than the hard sciences. And yes, as I’ve already indicated, I have considerable experience in evaluating statistical analyses. Though I myself am not a statistician, I have worked closely with statisticians and never had any problems communicating with them. And by the way, the shortcomings of statistics are readily conceded by the experienced statisticians with whom I have worked.

    As far as my “credentials” are concerned, let me quote some excerpts from an insightful Scientific American article, “Evaluating Scientific Claims”:

    Scientific knowledge is built on empirical data, and the details of the data . . . can vary quite a lot in different scientific disciplines, and in different areas of research within those disciplines. However, there are commonalities in the basic patterns of reasoning that scientists in all fields use to compare their theories with their data. . .
    In other words, even if I can’t evaluate someone else’s raw data to tell you directly what it means, I can evaluate the way that data is used to support or refute claims. I can recognize logical fallacies and distinguish them from instances of valid reasoning. Moreover, this is the kind of thing that a non-scientist who is good at critical thinking (whether a journalist or a member of the public consuming a news story) could evaluate as well. (https://blogs.scientificamerican.com/doing-good-science/evaluating-scientific-claims-or-do-we-have-to-take-the-scientists-word-for-it/# )

  31. 181
    nigelj says:

    alphagruis @172

    “If it doesn’t come “cheap” enough it won’t be done.”

    “This is simply not the case. Governments can and do force these things with regulations and / or subsidies.”

    “As I told you, that’s just wishful thinking.”

    Oh come on, with respect that’s just empty rhetoric without substance. You provide absolutely no evidence. Several countries have rules and subsidies and have cut emissions even although it has had short term costs, eg Great Britain, Germany, my own country to some extent, British Columbia, etc.

    “Like I said the large Study by Jacobson looked at all countries including Africa and the suggested balance of generation in each country. You can google the research easily enough.”

    “Done as soon as it’s been published !”

    “But, by the way, why don’t you google a critical review of all this “research” ?”

    I have. Nobody has really published a proper peer reviewed study discrediting Jacobson. It has been criticised in internet articles by the usual people with vested interests. No surprise there.

    And the more sensible critics admit he is right in theory. The quibbles are about costs etc. I think the point is he at least shows the possibilities and that things are not impossible. Its a very good starting point at the very least.

    “… all of the studies present comparatively little detail on strategies to decarbonize the industrial and transportation sectors, and most give superficial treatment to relevant constraints on energy system transformations.”

    “Strawman yet again. Jacobson was only ever looking at renewable energy. Decarbonising industry is challenging, but some countries are tackling it with cap and trade schemes which encourage innovation.

    “And everybody, New Zealand and Iceland included, still imports large amounts of fossil fuels for transport, agriculture”

    “Yes thanks for the history lesson, but this is slowly changing and can change if we collectively want it to change. Obviously you don’t want it to change.”

    “Obviously ?”

    “Amazing.”

    Empty rhetoric, and you haven’t answered the question, and stated your position openly and forthrightly.

    “At any rate what I (or you) want or don’t want is quite irrelevant. Reality is very stubborn.”

    No its not irrelevant. What we (myself and a good many others) want to do to protect ourselves and the planet. Looks like you want to give up because things are difficult.

    “In spite of of all the hydro, geothermal and wind in NZ there is still a long way to go”

    Another straw man graph. Renewable energy in NZ has a long history, and has kept CO2 emissions lower than they would have been. We have not cut much indistrial CO2, and we have high methane emissions from agriculture. We are working on it all, while you sit in your armchair and criticise, and spread negativity!

  32. 182
    Mr. Know It All says:

    152 Donna and 162 Susan Anderson

    Many people who have reviewed the claims of AGW, just do not believe them. The climate has always changed, and that is a good argument against a belief in AGW

    [Response: No it’s not. It’s a terrible argument. It’s a logical fallacy. You should probably understand that. -gavin]

    – it is not proof of it of course – there is no absolute proof. The fact that many high temp records occurred long ago when CO2 levels were less is another piece of evidence.

    [Response: Also a logical fallacy. 0/2 so far. – gavin]

    And the 18 year no-warming period is another piece,

    [Response: Cherry pick of both period and datasets. 0/3]

    and the constant adjustments of the temperature records and data is more evidence – even pointing to nefarious activity by some scientists.

    [Response: Ha! Red herring and ad hom! 0/4.]

    AGW may be real, but there is plenty of evidence to cause a reasonable person to question whether it is or not. Most don’t have the science background to investigate the science so they can only weigh what is presented by the media.

    [Response: Fortunately many people can see through this kind of fallacious reasoning even if they don’t have a background in the science. You seem like you should be able to as well, so that raises the question of why you use them? Let me guess: you object to policies that ppl have proposed to deal with AGW. Fair enough – but stop dicking about with tedious BS like this and argue about what you really have a problem with. You’ll gain respect and perhaps deeper engagement. – gavin]

  33. 183
    Thomas says:

    Alphagrius @168, did you fully read what I wrote and the subject/context?

    Anyway, I was going to say this my words, but why not quote the experts directly?

    Welcome to the Department of Cognitive Science

    The Department of Cognitive Science is a research department which carries out research and PhD supervision across a wide range of domains of cognitive science, including memory, language, belief formation, perception in action, and reading. The Department hosts the ARC Centre of Excellence in Cognition and its Disorders, which brings together researchers from the Departments of Cognitive Science, Psychology and Linguistics at Macquarie University and thirteen other national and international institutions.
    https://www.cogsci.mq.edu.au/

    or maybe
    Cognitive science is the interdisciplinary study of mind and intelligence, embracing philosophy, psychology, artificial intelligence, neuroscience, linguistics, and anthropology.
    Its intellectual origins are in the mid-1950s when researchers in several fields began to develop theories of mind based on complex representations and computational procedures.

    Its organizational origins are in the mid-1970s when the Cognitive Science Society was formed and the journal Cognitive Science began. Since then, more than ninety universities in North America, Europe, Asia, and Australia have established cognitive science programs, and many others have instituted courses in cognitive science.
    https://plato.stanford.edu/entries/cognitive-science/

    You may consider doing a RC search including my name and psychology and George Lakoff or anything close to it, and check out the ref links I have provided for the benefit of others. Even add in “marketing” or “advertising” along the way. See what pops up… it’s all connected with the hard problems of agw/cc today.

    Or jump in these refs:
    http://programsandcourses.anu.edu.au/program/BSPSY
    https://theconversation.com/is-psychology-a-science-10126

    or google is your friend (well kind of, it’s also a demon imho)

  34. 184

    KIA 181: Many people who have reviewed the claims of AGW, just do not believe them.

    BPL: Logical fallacy: Argument from incredulity.

    KIA: The climate has always changed, and that is a good argument against a belief in AGW

    BPL: Logical fallacy: Non sequitur. Your argument is like saying, people have died of natural causes for thousands of years, so this guy with the butcher’s knife in his back must have died of natural causes.

  35. 185
    alphagruis says:

    nigelj (#181)

    Oh come on, with respect that’s just empty rhetoric without substance. You provide absolutely no evidence. Several countries have rules and subsidies and have cut emissions even although it has had short term costs, eg Great Britain, Germany, my own country to some extent, British Columbia, etc.

    No, sorry. I’m the one who provided the evidence and you are the one who plainly ignores it and spouts “empty rhetoric” instead.

    And simply lies (or with respect… wishful thinking.)

    Germany has not decreased its emissions as a consequence of the “Energiewende”. It’s precisely the reverse as I already told you !!!

    But you don’t like the facts and… remember they are very stubborn.

    Another straw man graph

    No, sorry again. No straw man graph at all.

    NZ is among the largest CO2 emitters per capita on this planet.

    Again, just a fact but you don’t like the facts and… remember they are very stubborn.

    So, since you neither hear nor like what I tell you, I won’t further insist.

    Just for your info: I’m not at all against renewable energies of course but I’m a physicist, know a bit about the laws of physics and the relevant constraints. Nobody can force renewables into use right now because of the climate or any other reason.

    Remember facts are very stubborn.

  36. 186
    Obstreperous Applesauce says:

    Ray:

    “You are a perfect example of what stupidity looks like when it gets sent to college.”

    I am so stealing that!
    Beautiful!

  37. 187
  38. 188
    Bob Loblaw says:

    Victor @180: “nor, unlike so many posting here, do I see myself as any sort of “expert.”>

    Yes, we believe you’re not an expert, Victor. You don’t need to tell us this, and you certainly don’t need to keep posting more evidence. Your posts here have provided far more evidence than is needed to conclude that you are not an expert. Feel free to stop any time.

  39. 189
    nigelj says:

    Mr Know it all @182

    “and the constant adjustments of the temperature records and data is more evidence – even pointing to nefarious activity by some scientists.’

    This is rubbish of course, but also hilarious, because the “constant adjustments” to the largest and most important data, the global land / ocean trend since 1900 – 2016, actually reduces the ****** warming trend!

    https://skepticalscience.com/how-data-adjustments-affect-temp-records.html

  40. 190
    jgnfld says:

    @180…

    Why is it that amateur nonscientists are continually quoting sophomore philosophy and history of science to professionals with decades of experience?

    If I started spouting sophomore semiotics and its relations to Dan Brown’s “symbology” would you be impressed? Possibly so given the evidence.

  41. 191
    Thomas says:

    RE 182 onward

    and UV #380 David B. Benson, good ref

    And so ‘they’ keep saying the climate has always changed and yet ‘they’ always stop short of saying what is the whole truth this article points out truthfully and scientifically that “scientists have discovered, this has happened many times before, and sometimes the results were catastrophic.”

    “….the paleontologist David Bond and the geologist Stephen Grasby write in the journal that most mass extinctions were marked by “global warming, anoxia and ocean acidification, driven by changes in atmospheric CO2.”

    After synthesizing a vast body of literature and reviewing almost 20 global mass extinctions over the past half billion years — including the most extreme ones, the so-called Big Five — the authors concluded that “large scale volcanism is the main driver of mass extinctions” and that “most extinctions are associated with global warming and proximal killers such as marine anoxia.”
    https://www.nytimes.com/2017/07/29/opinion/sunday/when-life-on-earth-was-nearly-extinguished.html

    Prof. Peter Ward UW is great resource for everyday people to easily learn more about these matters – eg 2013 Who is Afraid of the Big Bad Climate? What is the Worst That Global Warming Could Do? https://www.youtube.com/watch?v=HP_Fvs48hb4&feature=youtu.be&t=33m1s

    This stuff is not new science …. neither are Logical Fallacies as already noted or severe Cognitive Dissonance and those people suffering from that condition who are repeatedly Lying to themselves and everyone they meet online
    http://www.uncommon-knowledge.co.uk/articles/stop-lying.html

  42. 192
    nigelj says:

    alphagruis @185

    Please provide your evidence that government rules / regulations relating to reducing emissions, government carbon taxes, and subsidies for renewable energy cannot work. Please provide something substantial and peer reviewed, with internet link. You haven’t, and resort to calling me a liar, which I totally reject.

    I have already given you several countries that have reduced emissions by implementing some sort of combination of government rules, carbon taxes, emissions trading schemes and subsidies for renewable energy, to get things started: Great Britian, NZ, British Columbia, and there are others, even America to some extent. The following is on Great Britain to show I’m no liar.

    https://www.theguardian.com/environment/2017/mar/06/uk-carbon-emissions-drop-to-lowest-level-since-19th-century-study-finds

    “Germany has not decreased its emissions as a consequence of the “Energiewende”.

    Germany is one example. One example proves nothing, and there are reasons for their difficulties relating to specific economic events, the nuclear issue and these are rather unique making Germany a terrible example to quote. I think they have over reacted a bit on the nuclear problem, just between you and me

    “Another straw man graph”
    “No, sorry again. No straw man graph at all.”
    “NZ is among the largest CO2 emitters per capita on this planet.”

    Another response that twists what I said, moves the goal posts, and deliberately misses the point, forcing me to repeat it. NZ has reduced at least some CO2 emissions by implementing renewable energy. Its emissions still remain high due to industrial and agricultural related factors relating to dairy farming, that are difficult to deal with. I only ever claimed we had a good renewable energy sector, and this is not changed by difficulties in other areas.

    “Just for your info: I’m not at all against renewable energies of course but I’m a physicist, know a bit about the laws of physics and the relevant constraints. Nobody can force renewables into use right now because of the climate or any other reason.”

    I cant make sense of any of that. Several countries already have renewable energy. I cant make any sense of a thing you say, or how you believe physics is a problem here. You dont explain why. I think renewable energy and other emissions reduction strategies are largely a political problems, not a physics problem or even a cost problem although of course there will be some costs especially with industrial emissions.But that doesn’t mean everything is a problem or not worth the effort.

    If you think climate issues being a political problem makes them difficult of course you are right. Perhaps that’s what you mean but you lack clarity. However to every problem there is a solution somewhere. Similar political problems have been overcome on many other matters, look at the reforms of Margaret Thatcher, or even Obamas own moves on climate change that had some success.

    With respect, your posts are lists of completely empty assertions and lack clarity. They are also just plain insulting ad hominems.

    You wont find many people more open minded than me, but I need to see clarity.

  43. 193
    Thomas says:

    Alphagrius @168 are you certain about that?

    Another example: Addicted to self deceit

    Westen and colleagues conducted a study using magnetic resonance imaging (MRI) scans on the brains of staunch Democrats and staunch Republicans in the USA. The MRIs showed that the emotional areas of participants’ brains lit up when they read articles suggesting their favored politician was dishonest. So far, so much what you would expect. But get this!

    There was a decrease in activity in the parts of the brain that deal with reasoning when they read this damning information. So part of reducing the discomfort of cognitive dissonance may be to think less. This makes sense. The flying saucer cultists, when confronted with their unfulfilled doomsday prophecy, didn’t think their way out of their dilemma, they felt their way out of it, and based their decisions on emotion.

    The researchers in Westen’s study found that all the participants appeared to find ways of ignoring any negative information relating to their favored politician, thus allowing themselves to hold on to their previous beliefs. When their emotional response eventually overcame the reasoning, it stimulated the brain’s reward system – similar to what happens to drug addicts when they get their fix. Nobody said that a sincere search for truth would be comfortable!
    http://www.uncommon-knowledge.co.uk/articles/stop-lying.html

    and another along the same lines:
    Why Do You Believe in God? Relationships between Religious Belief, Analytic Thinking, Mentalizing and Moral Concern by Anthony Ian Jack et al
    Abstract – Prior work has established that analytic thinking is associated with disbelief in God, whereas religious and spiritual beliefs have been positively linked to social and emotional cognition. […] We find that religious belief is robustly positively associated with moral concern (4 measures), and that at least part of the negative association between belief and analytic thinking (2 measures) can be explained by a negative correlation between moral concern and analytic thinking.
    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4805169/
    http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0149989#abstract0

    and
    Graph http://static1.1.sqspcdn.com/static/f/386437/18523516/1338570204210/comparisoneffects.png?token=H5Kg5Z%2FDQY3wL8hPNZ6dUhnSJt8%3D
    http://environment.yale.edu/climate-communication-OFF/files/Climate-Beliefs-November-2013.pdf

    and In Memory of E.G.
    http://www.realclimate.org/index.php/archives/2013/12/a-failure-in-communicating-the-impact-of-new-findings/#comment-430789

    Imho all the above and much much more is directly related to AGW/CC inaction, poor/ineffective communication of the scientific knowledge, and subsequent social/political conflict.

    Anywhere humans are involved ‘Psychology’ is involved.

  44. 194
    zebra says:

    Alphagruis #185,

    I haven’t followed your discussion with nigel that closely but I took notice when you said you are a physicist, who ” knows a bit about the laws of physics and the relevant constraints” because I found very little physics in anything you have written as I scanned the comments.

    One thing did strike me:

    Otherwise you need a truck to transport it to your location. And as far as physicists know carbon “neutral” wind and solar energy can’t power neither a truck nor a tractor.

    https://electrek.co/2016/12/05/john-deere-electric-tractor-prototype/

    Huh!

    The thing is, I know a bit about physics myself, and I don’t know of any constraints on wind and solar powering vehicles, including the many commercial electric trucks and buses already on the road. (google it yourself)

    In fact, these sources seem ideally suited to the applications, for reasons that should be obvious to anyone with a physics or engineering background, or even just a little reading on the topic.

    But I am always open to being enlightened on the internet, so why don’t you explain why things that have already been built can’t be built?

  45. 195
    MA Rodger says:

    jgnfld @190,
    The rather presumptive 1st-person quote saying “I can recognize logical fallacies and distinguish them from instances of valid reasoning” provided by Victor the Troll @180 was from a blog-piece of a philosophy professor, so not one of Victor’s “people with PhDs in … highly technical fields” who he argued @141 were fellow travellers on his journey into delusion. And this philosophy professor, Janet D. Stemwedel, in using her ability to “recognize logical fallacies and distinguish them from instances of valid reasoning” and also “to help us tell the people doing good science from the cranks,” has considered the evidence supporting AGW. Further, unlike poor deluded Victor the Troll, being “a non-scientist who is good at critical thinking,” Professor Stemwedel is not “out of (her) depth.” Indeed she feels strongly enough about the threat from AGW to actually be ‘hollering with (us)’ “We’re not talking about a political view, we’re talking about the facts!
    Mind while saying this, do note that Victor has elsewhere dismissed such argument as non-democratic fascism.

  46. 196
    Ray Ladbury says:

    OA,
    Steal away. I, myself stole it from P. J. O’Rourke, who undoubtedly liberated it from someone else.

    Also, people who liked this insult also liked:
    ignorant food tube
    dumber than owl shit
    and
    thinks he’s hot shit…well he’s half right.

  47. 197
    t marvell says:

    There needs to be a “probably truth” to counterbalance the deniers: That is, that the climate scientists are in denial about how dangerous global warming actually is. The climate deniers argue that the climate scientists have a self interest (especially grant funding) in exaggerating the human-caused global warming effects. But the scientists might also have an interest in understating it: They do not want to seem extremist, they do not want to suffer embarrassment should their prediction prove to be alarmist, and they might loose their funding if they contend that extreme measures (such as eliminating carbon fuel in a few years) are necessary.

    For some time CO2 levels and temperature have been increasing exponentially. Even if CO2 levels stop growing, temperatures must increase for decades due to the lagged effect of CO2. In fact, there is no sign that CO2 growth is abating or that world leaders contemplate changes sufficient to reverse the CO2 trend.

    A specific example of the climate science community playing down the dangers is the common estimate the doubling CO2 will result in a temperature increase of about 2.5 degrees. That figure is far smaller than one would get by simply comparing CO2 and temperature trends in the past 100 or 150 years (during which CO2 levels started to grown).

    Another example is trumpeting gains in electricity produced by wind and solar energy. So far these are small, and there is no possibility that they can take over from carbon fuels for many decades.

  48. 198
    Mal Adapted says:

    Mr. Ironically Anosognosic Typist:

    Many people who have reviewed the claims of AGW, just do not believe them.

    Yep, thanks to the fossil fuel $billions invested over the past couple of decades in flooding the public sphere with disinformation, and to willfully benighted dupes like Mr. IAT.

    BTW, unlike Mr. IAT’s conspiracist fantasies, the Koch Club investment strategy is ‘presumptively legal’, and abundantly documented in the public record. Dark Money, by Jane Mayer of the New Yorker magazine, is an exhaustive book-length investigative report. If you want peer-reviewed research, try Robert J. Brulle 2014, Institutionalizing delay: foundation funding and the creation of U.S. climate change counter-movement organizations, Climatic Change v122, pp 681–694.

  49. 199
    Mal Adapted says:

    Ray Ladbury:

    thinks he’s hot shit…well he’s half right.

    Or: “He thinks he’s a wit, but he’s only half-right.” 8^D

  50. 200
    nigelj says:

    Thomas @193, the research you quote looks good, and is consistent with things I have read.

    Humans process information in confused ways, have biases, to greater or lesser extents, and self deception. We are not all the same however, its shades of grey. Some people can be intelligent yet still have a very poor grasp of simple logic (Victor, despite his protestations).

    Evolution is messy

    But you say:

    “Imho all the above and much much more is directly related to AGW/CC inaction, poor/ineffective communication of the scientific knowledge, and subsequent social/political conflict.”

    I’m stuggling to know what more scientists can do in terms of communication. I have asked myself and others the same question you have asked. People are given the facts in clear enough form, then their addled brains scramble the facts.

    Skepticalscience.com has made an effort with some good articles on logical fallacies, red herring arguments, etc, and analogies to explain the greenhouse effect. Its to innoculate against the doubters. Perhaps we just need more of this everywhere.

    The problem is the campaign to spread doubt which artfully hooks into peoples prejudices, emotional buttons, and poor reasoning skills. I think this needs to be countered blow by blow. There’s no easy answer that I can see. If there was one it would have been found by now.