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Unforced variations: Mar 2018

Filed under: — group @ 28 February 2018

This month’s open thread for climate science related items. The open thread for responses to climate change is here.

408 Responses to “Unforced variations: Mar 2018”

  1. 251
    Bob Loblaw says:

    nigelj @ 235: Sorry but you don’t get to exclude a year or two years data when computing a trend.

    Oh, but you are forgetting the denier rules on including years with El Nino events in temperature trends.

    El Nino years in the middle are not ruled out, but not encouraged.

    El Nino years at the end of a series are bad, bad, bad, and must be avoided at all costs. They distort the trend [that the deniers want to see…]

    El Nino years at the start of a series are God’s Gift To Good [Blog] Science. They have no distorting effect on trends at all. They are not only encouraged, they get the Good Housekeeping Seal of Approval. In fact, if you do not have an El Nino at the start of your series, you must make every effort to adjust your series so that it does start with an El Nino.

    Ignore these rules at your peril.

  2. 252
    Thomas says:

    Casting a casual eye over that global temperature anomaly image above, roughly indicates to me (at least) that about 60% of the earth’s surface above the 60N latitude is experiencing observed temperature anomalies between +4C and +14C during the last 3 months.

    I don’t know about you, but I find that a quite serious current affair and really worth telling the world about it. I think they have a right to know the truth about this Science knowledge and what that truth intimates and could mean to them both in the short and longer terms.

    YMMV, of course.

  3. 253
    Thomas says:

    What does the Science say?

    1) Climate changing ten times faster than historic natural variation.

    2) And sea levels are rising faster causing flooding in many coastal cities.

    ABC Radio National on The Science Show – only 13:19 mins
    http://radio.abc.net.au/programitem/pgW6zerKJG?play=true

    In simple words even a Federal Court Judge could understand.

  4. 254
    Hank Roberts says:

    V:

    it’s been much easier to demonstrate the fact that increased levels of atmospheric CO2 have a warming effect than to establish the degree to which that warming effect makes a difference

    Do you still smoke cigarettes?

  5. 255
    jgnfld says:

    @245

    Re. “Observations conducted in the field require special equipment and also protocols for interpreting the interaction between that equipment and the objects under study, protocols that are often far from obvious and possibly erroneous.”

    Would you care to point out a single scientific measurement in the most controlled of labs which does NOT require special equipment and also protocols for interpreting the interaction between that equipment and the objects under study?

  6. 256
    CCHolley says:

    Victor @244

    That is NOT true of AGW, where many perfectly legitimate doubts as to its viability have been raised by many highly trained and respected scientists. As they see it, and as I see it, AGW remains “only a theory.”

    Many legitimate doubts as to its viability have been raised? Hardly, that is just a figment of your imagination.

    I think you need to refresh yourself on the definition of theory in scientific parlance:

    A scientific theory is an explanation of an aspect of the natural world that can be repeatedly tested, in accordance with the scientific method, using a predefined protocol of observation and experiment. Established scientific theories have withstood rigorous scrutiny and embody scientific knowledge.

    There is no such thing as just a theory in science. In science a theory must be well founded and accepted. It is not the same as a “theory” in common usage, in science that would be a hypothesis. You really don’t know much about science, do you?

    Bottom line: as should be evident from our exchange, there is no way to establish a trend of any kind without a certain amount of cherry picking. The fact that the choice of endpoints can make such a difference is in itself a strong argument against the validity of a strictly statistical approach.

    Baloney, it has always been stated that a statistically valid trend in global temperatures requires thirty years of data. Thirty years eliminates cherry picking. End points don’t matter. If you want to establish the current trend in temperatures start with the current data, 2017 and go back thirty years. That’s the bottom line.

    In every case, endpoints must be chosen and different endpoints will invariably produce different results.

    sheesh, pick any end points you want for any thirty trend you want to determine. Thirty years my friend if you want to determine a statistically meaningful temperature trend.

    Contingency

    You miss the point, all changes in historical climates must conform to the laws of physics and any explanation must conform to such laws. A long term change in climate requires a change in the radiative balance. We know what all the possible drivers of such changes are. Period. There may be historical situations where there is not enough data to make a precise determination what particular drivers apply, but all the possibilities are well understood and in most cases a good judgement can be made to determine which ones do apply. There are no unknown magical causes of climate change.

  7. 257
    Mel Reasoner says:

    Victor 244: “It should go without saying that the leveling off to which I referred is based on data that’s been accepted by many mainstream climate scientists.”

    It appears that you agree with many mainstream climate scientists. Are you sure that you’re not getting sucked into the ‘groupthink’?

    Also, maybe you could shed some light on the extent to which you reject physics for explaining warming and cooling trends in Earth history and provide a few details on your alternative to a strictly statistical approach for determining trends. This is a science form and I’m sure the moderators would agree that this is a good place for kicking around these kind of novel ideas.

    V: “By the same token, you should not insist on including 2015 and 2016 simply because they produce the trend you are looking for.”

    You’ve got this horribly wrong, I’m not looking for a trend. It appears, however, that you are.

    V: “1998 was the year YOU chose, which is why I used it.”

    Wrong again. As I explained in the post, 1998 was the year chosen, or more accurately cherry-picked, by many fake skeptics (Including Christopher Booker, the author of the ‘essay’ you were peddling upthread) to make claims like “the global temperature trend has now shown no further warming for 19 years.”

  8. 258
    nigelj says:

    I cannot believe the moderators publish this utter, tedious, vacuous, petty crap by Victor. Sorry in my varied roles I was once a quality assurance manager for a leading edge corporate. I just have to say something for my own sanity. Or maybe you guys are having a good laugh! Ah ha thats got to be it.

    “V: OK, thank you very much, BPL, for taking the trouble to track down these very interesting references and provide some useful quotations. I’m not a physicist (are you?) so not in a position to evaluate any of this as physics per se, but it is certainly well worth considering. Before doing so, however, let me backtrack a bit:

    V: Yes. Confirmed under controlled laboratory conditions.

    BPL: No, confirmed by direct observation of the environment.

    V: I’m not a physicist but I have been active in other branches of science and I do think I know something about scientific method. So, with all due respect, I must insist that there is no such thing as “direct observation of the environment.” Observations conducted in the field require special equipment and also protocols for interpreting the interaction between that equipment and the objects under study, protocols that are often far from obvious and possibly erroneous. Nor are observations drawn from the study of the real-world environment, where conditions may vary greatly from one observation to the next, subject to the sort of controls readily available in the laboratory.”

  9. 259
    nigelj says:

    Victor @244

    “V: Well, what do you mean by “all the years”? Beginning when, with the Big Bang? Ending with the apocalypse? In every case, endpoints must be chosen and different endpoints will invariably produce different results.”

    Im not sure why you would suggest a global temperature trend going back to the big bang. The earth didn’t exist then.

    We do have reconstructions going back thousands of years, and the farther back the better, and to the origins of the planet 4 billion years ago if possible. What a marvellous graph that would make.

    And obviously you graph trends to the latest date and data possible. Can you explain why you wouldnt, unless you wanted to hide something?

    You remind me of Basil Fawlty in the television series Fawlty Towers.

  10. 260
    Ray Ladbury says:

    Weaktor@245

    Whoa! Look out for those rapidly moving goalposts!

    Dude, BPL and I are both physicists. So are the good folks at the American Physical Society and the American Geophysical Union and many of those who have evaluated the science for the National Academy. So, pray, why do you feel qualified to cast aspersions on the work of thousands of climate scientists when you are by your own admission unqualified to evaluate even the basics of the science?

    Regarding feedbacks, have you even looked at the science? Have you looked at the probable ranges for the different contributing sources to the net feedback? Do you realize how improbable it is that the net feedback is negative

    Or do you posit some magical negative feedback, still unknown and unobserved despite the continual efforts of scientists for over two centuries, that will rescue us? Dude, you really are the poster child for what happens when stupid gets sent to college!

  11. 261
    Astringent says:

    245 Victor says:


    V 206: CC: . . . Contrary to Victor’s statements, the result of the application of physics to the greenhouse gas theory has been confirmed through direct observations.

    V: Yes. Confirmed under controlled laboratory conditions.

    BPL: No, confirmed by direct observation of the environment. Back-radiation has increased in just the absorption lines of greenhouse gases. That’s the absolute smoking gun, of all the six or so smoking guns that confirm AGW. Here are some references:

    V: OK, thank you very much, BPL, for taking the trouble to track down these very interesting references and provide some useful quotations. I’m not a physicist (are you?) so not in a position to evaluate any of this as physics per se, but it is certainly well worth considering. Before doing so, however, let me backtrack a bit:

    V: Yes. Confirmed under controlled laboratory conditions.

    BPL: No, confirmed by direct observation of the environment.

    V: I’m not a physicist but I have been active in other branches of science and I do think I know something about scientific method. So, with all due respect, I must insist that there is no such thing as “direct observation of the environment.” Observations conducted in the field require special equipment and also protocols for interpreting the interaction between that equipment and the objects under study, protocols that are often far from obvious and possibly erroneous. Nor are observations drawn from the study of the real-world environment, where conditions may vary greatly from one observation to the next, subject to the sort of controls readily available in the laboratory.

    Now as far as your references are concerned, naturally I am in no position to evaluate the physics involved, but I could not help but notice that the bottom line in each case seems a bit equivocal:

    “This experimental data should effectively end the argument by skeptics that no experimental evidence exists for the connection between greenhouse gas increases in the atmosphere and global warming.”

    Looks suspiciously like a straw man. I don’t know of any skeptics who would argue that there is no such connection. It’s the degree to which the connection matters where the disagreement lies.

    Well perhaps you should pay more attention to politics: ‘Scott Pruitt, Donald Trump’s head of the US Environmental Protection Agency, has dismissed a basic scientific understanding of climate change by denying that carbon dioxide emissions are a primary cause of global warming. Pruitt said on Thursday that he did not believe that the release of CO2, a heat-trapping gas, was pushing global temperatures upwards.’

    But you should also look at your own thought process. You demand ‘evidence’ from outside a laboratory implying that lab based science isn’t relevant – when it is given to you you claim that it can’t be trusted, in part because it isn’t subject to the same rigorous controls as lab based science. It’s a rather tired meme, basically on a par with saying ‘where’s the evidence of temperature rise’ and then when you are given it saying it can’t be trusted ‘because measuring temperature is difficult’.

    Have you thought that perhaps, as ‘not a physicist’ and basing your pontification on ‘my impression, which could be totally off base’, that given all these uncertainties maybe scientists are wildly underestimating feedbacks, and things are worse than we know? I’m fairly sure that if someone sat down and explained a specific forcing, say the snow-melt albedo feedback loop, you would start of by claiming that a) no one knows, b) people have only ever melted snow in the laboratory, c) you can’t trust observations of melting snow because it’s cloudy over the north pole, before moving on the the usual d) well melting snow might actually be good for humanity and e) it’s not important to focus on one forcing and it’s uncertainties it’s the system response that matters.

  12. 262
    CCHolley says:

    Victor @245

    My impression, which could be totally off base, is that it’s been much easier to demonstrate the fact that increased levels of atmospheric CO2 have a warming effect than to establish the degree to which that warming effect makes a difference, both in determining the temperature of the Earth and producing conditions that could become dangerous at some future date. From what I’ve read, a great deal hangs on the interpretation, and significance, of various feedbacks, both positive and negative, a topic that would appear to be highly debatable.

    You would be correct, to a point. Determining the response of the feedbacks is what results in the uncertainty of predicting climate sensitivity. That is why it is given as a range. However, the physics puts a lower bound constraint on how low that number can be. As stated earlier, which you continue to ignore, is that the physics tells us the lowest climate sensitivity with the water vapor feedback and lapse rate would be at least 2 degrees celsius. Not only that, satellite measurements indicate that the current increase in humidity is greater than expected meaning that number is likely higher.

    Although there is uncertainty in the remaining feedbacks, there is no known negative feedback that would off-set any of that 2 degrees.

    Clouds were a possibility, but observations from satellites show that as it warms, clouds are not increasing. Not only that, clouds are generally moving away from the equator making it likely that they are a positive feedback as more sunlight will reach the equator where most heating occurs. There have been zero observations to show clouds are a net negative feedback. Lindzen proposed his iris cloud effect which was suppose to result in a large negative feedback, but since he made his hypothesis back almost 20 years ago there have been zero observations to indicate any iris effect. He was wrong. Other than that, there are no other possible major negative feedbacks. (The Stephan-Boltzmann Law, although Roe says its not a feedback, and lapse rate are minor negative feedbacks and are not controversial. Physics generally takes care of that.) Contrarians like to pretend there could be other negative feedbacks because that is what would be needed for low climate sensitivity, but none have been identified and observations along with physics tells us none will likely be discovered.

    The remaining feedbacks of consequence are positive, but are difficult to determine precisely due to how fast they will respond. These major feedbacks beyond water vapor are multiple changes in the carbon cycle and changes in albedo. These feedbacks are what tells us climate sensitivity will be larger than the 2 degrees and most likely in the 3 to 4 degree range.

    How much is dangerous? It depends on which generation you care about. Lower climate sensitivity only means it will take longer to warm, but warm it will with the resulting consequences. Sea levels will rise, changes in weather patterns will occur effecting the biome and agriculture. And so on. It is just a matter of time.

  13. 263

    Guys, thanks for getting my back.

    I just have one question left for Victor at this point: What evidence would you accept that you might be wrong? So far you’ve argued with every bit of evidence presented. If there isn’t any you’d accept, under any circumstances, then whatever you’re doing, it’s not science.

  14. 264
    Brian Dodge says:

    Re sea level rise acceleration

    Increasing rates of ice mass loss from the Greenland and Antarctic ice sheets revealed by GRACE; I. Velicogna; GEOPHYSICAL RESEARCH LETTERS, VOL. 36, L19503, 2009; doi:10.1029/2009GL040222
    “The best fitting estimate for the acceleration in ice sheet mass loss for the observed period is 30 ± 11 Gt/yr2 for Greenland and 26 ± 14 Gt/yr2 for Antarctica. This corresponds to 0.09 ± 0.03 mm/yr2 of sea level rise from Greenland and 0.08 ± 0.04 mm/yr2 from Antarctica.”
    “To verify that the improvement obtained with the quadratic model is significant we used an F-test [e.g., Berry and Feldman, 1985]. The F-test show that the improvement obtained with the quadratic fit is statistical significant at a very high confidence level.”
    “We showed that a detailed analysis of the GRACE time series over the time period 2002–2009 unambiguously reveals an increase in mass loss from both ice sheets. The combined contribution of Greenland and Antarctica to global sea level rise is accelerating at a rate of 56 ± 17 Gt/yr2 during April 2002–February 2009, which corresponds to an equivalent acceleration in sea level rise of 0.17 ± 0.05 mm/yr2 during this time. This large acceleration explains a large share of the different GRACE estimates of ice sheet mass loss published in recent years. It also illustrates that the two ice sheets play an important role in the total contribution to sea level at present, and that contribution is continuously and rapidly growing”

    https://www.cambridge.org/core/services/aop-cambridge-core/content/view/C092B387C12554617005F8BE99062DC3/S0260305500251513a.pdf/div-class-title-six-decades-of-glacier-mass-balance-observations-a-review-of-the-worldwide-monitoring-network-div.pdf
    “The 30 reference glaciers with continuous observation series since 1976 show an accelerated thinning, with mean annual ice losses of 0.14m w.e. (1976–85), 0.25 mw.e. (1986–95) and 0.58m w.e. (1996–2005), which gives a total average ice-thickness reduction of about 10m w.e…….Mass balance is recognized asan essential climate variable within the global climate-related observing systems and is, in effect, the largest non-steric contributor to the global sea-level rise at the turn of the century.”

  15. 265
    Victor says:

    Since my most recent response has been consigned to the bore hole, I see no reason to continue this discussion. I would like, however, to leave us with the following words of wisdom:

    STATEMENT TO THE COMMITTEE ON SCIENCE, SPACE AND TECHNOLOGY
    OF THE UNITED STATES HOUSE OF REPRESENTATIVES, presented by Judith Curry on March 29, 2017 (https://science.house.gov/sites/republicans.science.house.gov/files/documents/HHRG-115-SY-WState-JCurry-20170329.pdf):

    Scientific arguments in physics, chemistry and cell biology are typically based on controlled laboratory experiments, where explanation and prediction can be based on a few variables. There are elements of climate science that can be addressed using these methods, notably in atmospheric chemistry and the physics and chemistry of aerosol and cloud particles. However, scientific investigations of the dynamics of the entire climate system have more in common with systems biology and economics than with laboratory physics and chemistry, owing to the complexity of the systems under investigation and the inability to conduct controlled experiments. Complexity of the climate system arises from chaotic behavior and the nonlinearity of the equations for motions in the atmosphere and ocean, high dimensionality of the system (many different variables, varying in three dimensions and with time), and the linking of multiple subsystems (e.g. atmosphere, oceans, land surface, glacier ice).

    The aggregate properties and changes of complex systems cannot be determined from sum of the individual components, owing to interactions among the components and the different scales of organization within the system. Complex systems are studied using information theory and computer simulation models (e.g. global climate models.) While some of the equations in climate models are based on the laws of physics, many key processes in the model are only approximated and are not directly related to physical laws. . .

  16. 266
    jgnfld says:

    @265

    Along the same lines as your objections, it is pretty much impossible to do experiments in astrophysics. The only data we generally have is observational data from photons of various frequencies, observations of particles, and observations of gravity waves.

    The only way we really “know” that stars are giant balls of fusing elements is that the observational data–spectra mainly–fit math models. I don’t see you questioning the existence of various astrophysical phenomena with such vigor. Yet no one can actually “prove” they exist to the standards you demand of climate science.

    Your–well Judith’s–notions of emergent properties of systems are, uh, interesting. And they seem a bit magical more than physical. But the fact is there are many methods of measuring the “aggregate properties” of “complex systems” even where perfect precision is impossible. Turbulent flow still follows physical laws, for example. Chaos does not mean nondeterminism. And chaotic systems can never run outside of physical constraints.

  17. 267
    MA Rodger says:

    The boreholed comment that Victor feels so agrieved about that he makes to go off in a huff wasn’t that different to one boreholed in 2016 although back then Victor kept on going – there are quite a few boreholed Victor-comments rubbing shoulders from that time.
    Part of the latest boreholing not re-commented @265 and part of the 2016 boreholing concerns that “long list of scientists who seriously doubt the mainstream view of climate change.” Back in 2016 Victor managed to supply a link to the list that comprises Judith Curry, Richard Lindzen and Fred Singer and Spencer and Soon and Scarfetta and Svensmark and Christy and … Did I say Judith Curry? And beyond that it’s a whole lot more of increasing embarrassment.

  18. 268
    Ric Merritt says:

    Should you choose to argue with a troll about imaginary pauses and imaginary trends, going on at length about statistics is trying to teach a pig to sing. Don’t.

    Just demand that they find, or predict, a calendar decade no warmer than the last. Any bets on 2000-2009 versus 2010-2019? Should you get a straight answer, make bigger bets on decades 20 and 30 years apart.

    You’ll get some combination of blathering distraction and crickets.

  19. 269

    Victor, #265–

    …many key processes in the model are only approximated and are not directly related to physical laws. . .

    IOW, empirically-determined parameterizations. As the kids used to say, “Whatever.”

    Have a nice life ’til next time, Victor!

  20. 270
    CCHolley says:

    Victor @265

    Since my most recent response has been consigned to the bore hole, I see no reason to continue this discussion.

    Let’s look at Victor’s argument in the borehole (where it belongs)

    I think the best way to respond to all the objections of those insisting that the physics behind the science of climate change is both “well understood” and “incontrovertible” is to encourage you all to study this document.

    The document in question is A Tutorial on the Basic Physics of Climate Change published by the American Physical Society.

    here is the link: https://www.aps.org/units/fps/newsletters/200807/hafemeister.cfm

    The abstract: In this paper, we have used several basic atmospheric–physics models to show that additional carbon dioxide will warm the surface of Earth. We also show that observed solar variations cannot account for observed global temperature increase.

    Victor goes on to say:

    I won’t be disputing any of the physics presented in this document for the simple reason that I’m not a physicist and am thus not qualified to dispute it. The point of this little exercise is not to challenge the physics, but to give a sense of how complicated it is.

    So Victor acknowledges that he cannot comment on the physics presented because he is clueless, but states that it is complicated as if this somehow makes it less valid. Victor simply uses his personal incredulousness, a logical fallacy, to attempt to cast doubt on the science.

    The paper actually shows how robust the physics actually is. That it IS irrefutable.

    Yet Victor then makes the following claim:

    If any one of the many claims, analyses, observations, equations, etc. is erroneous or misinterpreted then the whole thing threatens to come tumbling down.

    But then again Victor is not qualified to make such a judgment, especially when it comes to the veracity of the physics or the mathematical representation of that physics. However, because he does not like the conclusions, science built on two hundred years of peer reviewed work in his mind just might be wrong. Why? Because it is complicated.

    While we’re on the paper, we may as well look at the conclusion. This is put out by the American Physical Society mind you, not some shleppy organization.

    Conclusion: Earth is getting warmer. Basic atmospheric models [based on physics] clearly predict that additional greenhouse gasses will raise the temperature of Earth. To argue otherwise, one must prove a physical mechanism that gives a reasonable alternative cause of warming. This has not been done. Sunspot and temperature correlations do not prove causality.

    Then Victor seems to think that Judith Curry is reliable even though she has been shown to be wrong so many times it makes my head spin.

    From her testimony: complexity of the climate system arises from chaotic behavior and the nonlinearity of the equations for motions in the atmosphere and ocean, high dimensionality of the system (many different variables, varying in three dimensions and with time), and the linking of multiple subsystems (e.g. atmosphere, oceans, land surface, glacier ice).

    So what? Climate is complicated and exactly how it will respond to warming is covered in the uncertainty of the climate sensitivity and the uncertainty in attribution. She is just pontificating.

    We are focused on warming. The climate system reacts to warming, it does not cause it. The physics behind what drives the radiative balance of the earth system and hence warming is well understood. Increases in CO2 will cause warming of at least 2 degrees per doubling. Arguments of complexity can be made ad infinitum, but they will not change this basic fact.

    The Curry argument that I’ve heard is basically that since climate is complicated there could be other unknown causes of warming. Natural causes. An argument that Victor probably salivates over because he is admittedly clueless and it fits his myopic world view.

    Well we have natural unforced variation, but of course the possibility of such is limited because natural cycles are only caused by a redistribution of heat in the climate system. Since no heat is created, the amount of surface warming that results is limited. It’s physics, heat can only move from hot to cold and systems must move to thermal equilibrium. It is understood that natural variation can only account for plus or minus 0.15 degrees about the forced mean. It cannot account for much, if any, of the warming since industrialization. That would require a change in energy balance.

    Since natural unforced variation cannot account for the warming it can only be some natural change in forcing. This would have to result in more energy into the system or less energy out. Number one suspect, the sun. Nope, solar has been declining. See paper Victor referenced above. Where else can more energy come from? Fewer clouds? Nope, clouds have been stable not to mention what natural force could possibly diminish clouds? Nothing. How about preventing energy from escaping? What are the *natural* possibilities? There are none. Curry has provided no possibilities nor has anyone else.

    The argument for *other* causes is hollow. There are no known possible alternatives. One must prove their existence, no one has, no one can. Its physics. And physics says climate sensitivity is not low.

    But the self described clueless Victor knows better. Climate is complicated. He wrote a book.

  21. 271
    Dan says:

    re: 265.
    A. Read about Judith Curry’s background before simply regurgitating what you want to believe. Because that is precisely what you are doing. Classic intellectual laziness.
    B. You have not made any attempt to learn and understand the scientific method as many have pointed out to you. You know, the method that has been followed for centuries and is the cornerstone of all science.
    C. Based on B, you should not be surprised that your recent response was relegated to the bore hole.
    D. Similarly, your inability to admit to being fundamentally wrong on so many issues speaks volumes. Mostly about a complete failure to understand science, a failure to learn and extreme insecurity.

  22. 272
    Killian says:

    This helps clarify why the ice sheets are melting so fast, and accelerating.

    https://www.upi.com/Science_News/2018/03/14/Fast-draining-lakes-threaten-vulnerable-Greenland-ice-sheet/2321521030289/

  23. 273
    Killian says:

    #264 Brian Dodge said Re sea level rise acceleration
    …which corresponds to an equivalent acceleration in sea level rise of 0.17 ± 0.05 mm/yr2 during this time.

    That high end is around .04844 mm/yr?

  24. 274
    Victor says:

    I think I’ve said everything I wanted to say on the topics of groupthink, circular reasoning and the physics of climate change. Any attempt to respond to the most recent set of objections would necessitate repeating myself and no one wants that. If you’re curious you can reread what I’ve already written here, or sift through my old posts in either the archive or the borehole.

    Before leaving this thread, however, I would like to respond to the very reasonable question posted by Barton Paul Levenson:

    “I just have one question left for Victor at this point: What evidence would you accept that you might be wrong? So far you’ve argued with every bit of evidence presented. If there isn’t any you’d accept, under any circumstances, then whatever you’re doing, it’s not science.”

    Well for one thing I haven’t argued with the evidence so much as the way the evidence is being interpreted. Also I have never said I was doing science. I’m not a climate scientist and don’t pretend to be — as far as this field is concerned I see myself as a critical thinker.

    Now to your question:

    My first reaction was to turn the question back on you. I.e., what evidence would you accept that YOU might be wrong? This is in fact one of the key objections that’s been made to those supporting the mainstream view, that it cannot be falsified. All sorts of conflicting evidence has been presented by skeptics, but in each and every case it has been either rejected out of hand as absurd, or else explained away by introducing what I’ve called “fudge factors.” I’m sure you know what I’m referring to, so won’t repeat myself.

    Do you accept that the mainstream view cannot be falsified? And if so, how can you justify calling what YOU do science? Or, on the other hand, if you do accept that the prevailing hypothesis can be falsified, then what evidence for its falsification would YOU be willing to accept? Oh and please don’t fall back on evidence from the distant future because that would be far too easy and also pointless.

    Now as far as my views are concerned, first of all, strictly speaking I see no need to answer your question since the burden of proof is on the one who poses the hypothesis, not the one who challenges it. Moreover, if your position is full of holes, as I believe it is, then there is no one piece of evidence that’s likely to fill in all the many gaps and convince me that you’re right.

    Nevertheless, I CAN present a list of certain pieces of evidence that would go a long way to temper my skepticism. If a clear correlation between global temperatures and CO2 levels could be established without the need for invoking special circumstances; AND it could be established that sea levels have been accelerating in tandem with the acceleration of CO2 levels, again without the need for special pleading such as the invocation of Mt. Pinatubo’s eruption; AND if a relatively simple and clear demonstration of the amplification of the greenhouse effect produced by CO2 emissions via positive feedbacks could be presented; AND if important objections on the part of respected skeptics such as Drs. Curry, Lindzen, etc. could be convincingly refuted; AND . . . well you get the idea. It would take a lot, sorry, but that’s how I see it.

  25. 275

    V 274: Do you accept that the mainstream view cannot be falsified?

    BPL: No, of course not. It could be falsified by showing that quantum mechanics was wrong, or that Earth hadn’t actually been heating for the past 168 years, or that the US Air Force had gotten all the CO2 data in the HITRAN and HITEMP databases wrong. That’s just off the top of my head.

  26. 276
    jgnfld says:

    Of course the mainstream view can be falsified. The only problem is that a huge percentage of late 19th through 21st physics would also be falsified. Anything remotely involving spectroscopy for example (e.g. pretty much all of astrophysics for starters, but a whole lot more as well). Basically it’s not that the theory cannot be falsified as that it is highly unlikely given all the interlocking evidence.

    But let’s say suddenly one did not measure backradiation coming down at night! Then yes, the theory would be falsified in that obviously something was different. However it is highly unlikely that it would be the greenhouse effect. It would be some new factor masking the greenhouse effect. And then there is the trouble this would likely mean something had changed which would freeze the Earth.

    You simply do not understand correlation. You appear to look at a noisy rising line (e.g., temps) and say it cannot “correlate” highly with a relatively smooth line (e.g., CO2 rise) I guess because the short term noisy excursions in the one don’t match the smoothness of the other to your eye. This is patently wrong. You don’t do correlations by eye. You do correlations by math. And noise in one or the other series about a trend line is pretty much the normal case in the real world and constitute the very reason you calculate correlation coefficients.

    No. You are a committed denier for political reasons and will stay committed regardless. The science–theory and data–means nothing whatever to you. You have made that perfectly clear.

  27. 277
    CCHolley says:

    Victor @274

    AND if important objections on the part of respected skeptics such as Drs. Curry, Lindzen, etc. could be convincingly refuted; AND . . . well you get the idea. It would take a lot, sorry, but that’s how I see it.

    So, in other words no, you cannot ever be convinced because the objections of Drs. Curry, Lindzen, etc. have been thoroughly and convincingly refuted a hundred times.

  28. 278
  29. 279
    MA Rodger says:

    GISTEMP have posted for February with an anomaly of +0.78ºC, identical to January. It is =6th warmest February on record siting below Feb 2016 (+1.34ºC), 2017 (+1.12ºC), 1998 (+0.90ºC), 2015 (+0.87ºC), 2010 (+0.79ºC) and is tied with Feb 1995. So a lot of ENSO boosting in evidence.
    Feb 2018 sits as =42nd highest in GISTEMP anomaly on-record for all-months.
    The anomaly maps show a broader and higher warmth up in the Arctic as well as a dramatic deepening of the cold spot over N America, but if you’d been watching the TV news, you’d likely have already seen that reported.

  30. 280
    Brian Dodge says:

    “…many key processes in the model are only approximated and are not directly related to physical laws. . .”
    Who told you that? Did they (or can you) give an example?

  31. 281
    nigelj says:

    Victor @ 274

    “This is in fact one of the key objections that’s been made to those supporting the mainstream view, that it cannot be falsified.”

    What on earth does that statement mean? At face value are they complaining that the agw theory is so strong they cant falsify it?

    Or do they mean agw theory etcetera is structured so that it can’t be falsified? If the later, this is nonsense. Anyone can attempt to falsify the greenhouse effect, climate models etc by calculation, laboratory experiment and real world data. There are numerous theoretical avenues that could in theory falsify these things. We are not dealing with string theory, that is very difficult to prove or falsify because of the difficulty doing the appropriate experiments.

    But after decades nobody has falsified agw theory. Nobody has convinced the IPCC and vast majority of climate scientists that they have falsified agw theory. The most anyone has been able to do is show that climate sensitivity is not 100% certain, which everyone agrees with anyway. So you aren’t making any sense.

    “If a clear correlation between global temperatures and CO2 levels could be established without the need for invoking special circumstances;”

    What would you consider a clear correlation?

    I think your problem is the only correlation that would satisfy you is a perfect correlation where the fluctuating rise in CO2 is exactly mirrored by a fluctuating rise in temperature. Such a thing is impossible, because natural and other human forcings of a short term nature interfere in the trend seen in graphs.

    So only test of a clear correlation is statistical significance and CO2 passes this test easily enough.

    Correlations are rarely 100% in the way I have outlined. Look at smoking and disease for example, and its rough correlations, but only a fool would dismiss these correlations as insignificant.

    Once again correlations are rarely proof anyway. They tell us there could be a relationship between two variables, and even a “rough” correlation tells us this. The necessary ingredient is to have at least a rough correlation, it simply doesn’t have to be 100% perfect. The fact you cant see this is amazing. With climate change agw theory we have a statistically significant correlation, and very good causation with the greenhouse effect, so the science is very strong.

    The other issues you raise have been answered perfectly well before.

    “AND it could be established that sea levels have been accelerating in tandem with the acceleration of CO2 levels, again without the need for special pleading such as the invocation of Mt. Pinatubo’s eruption;”

    Climate change theory does not rest on Nemes paper on finding an acceleration over the last 30 years. The sea level rise raw data is not ideal, so doesn’t completely prove anything one way or another. What we have is a paper that certainly points strongly towards an acceleration, even if its not 100% proof.

    The research does consider topex data and the Mount Pinatubo eruption because those have been real world events. You cannot leave them out, just because you appear to not like them. Science doesn’t work that way. The way they have been analysed is also very compelling and detailed.

    “AND if a relatively simple and clear demonstration of the amplification of the greenhouse effect produced by CO2 emissions via positive feedbacks could be presented;”

    What are you suggesting? We shrink down the planet in size and put it in a laboratory? Simplicity like that cannot be done, so you have to use paleoclimate evidence, observation and modelling.

    Plenty of research has been done on the water vapour feedback and increasing levels of atmospheric humidity has been observed.

    I’m not a climate scientist but I know these things because I read up on them and I think logically and in detail, rather than wasting time in your empty, tedious style of rhetorical nonsense.

  32. 282
    CCHolley says:

    AND if important objections on the part of respected skeptics such as Drs. Curry, Lindzen, etc. could be convincingly refuted.

    Let’s take a look at Lindzen.

    In April of 2016 an administrative law judge in Minnesota recommended to the Minnesota PUC that it adopt the federal social cost of carbon after over a year of expert testimony.

    Arguing the science on behalf of Peabody Coal who claimed the costs were zero were Roy Spencer, William Happer, and gasp Richard Lindzen. The three attempted to show that climate sensitivity to CO2 was low and that half of the warming that we’ve experienced is natural by making certain claims about the natural variability of the earth’s climate. The judge essentially found their testimony to not be credible and made the following findings:

    22. The Administrative Law Judge concludes that Peabody failed to demonstrate that an equilibrium climate sensitivity of 1 or 1.5°C is correct.

    23. The Administrative Law Judge concludes that the climate sensitivity is reasonably considered to be in the 2-4.5°C range.

    So Lindzen’s views were rejected by an impartial judge after hearing all the evidence as were those of Happer and Spencer. I would have to say their objections were convincingly rejected by due process.

    Full records of the proceedings here:

    https://mn.gov/oah/assets/2500-31888-environmental-socioeconomic-costs-carbon-report_tcm19-222628.pdf

    Of course Lindzen’s only claim for low climate sensitivity is that of his “iris effect” which is a hypothesized strong negative feedback from higher altitude clouds in the tropics that would diminish with warming and allow more energy to escape to space. When first proposed in 2001, review by other scientists showed that his interpretation of satellite data was flawed and that he made assumptions that were inconsistent with known facts. When using more realistic assumptions, they were unable to verify his claims. The report is here:

    https://atmos.washington.edu/~dennis/IRIS_BAMS.pdf

    Lindzen published a paper in 2009 in an attempt to further support his hypothesis. A review of this paper showed significant errors. Lindzen later acknowledged his errors in an interview. Here is a critique of this paper from right here at Real Climate:

    http://www.masterresource.org/wp-content/uploads/2011/06/Attach3.pdf

    In 2011 he made another attempt to make a case for his iris effect hypothesis. His paper was rejected for publication by the National Academy of Science again due to significant flaws in his assumptions and science. The reviewers objections are thorough and his conclusions convincingly rejected. The rejection and reviewer’s comments are here:

    http://www.masterresource.org/wp-content/uploads/2011/06/Attach3.pdf

    If there is any doubt whether or not clouds are a large negative feedback as Lindzen claims, let’s look at more recent satellite studies, probably not conclusive, but certainly a fairly clear indication that it is wrong. For a high feedback it would really need to show up in the conditions studied.

    First: A Determination of the Cloud Feedback from Climate Variations over the Past Decade

    Abstract: Estimates of Earth’s climate sensitivity are uncertain, largely because of uncertainty in the long-term cloud feedback. I estimated the magnitude of the cloud feedback in response to short-term climate variations by analyzing the top-of-atmosphere radiation budget from March 2000 to February 2010. Over this period, the short-term cloud feedback had a magnitude of 0.54 ± 0.74 (2σ) watts per square meter per kelvin, meaning that it is likely positive. A small negative feedback is possible, but one large enough to cancel the climate’s positive feedbacks is not supported by these observations. Both long- and short-wave components of short-term cloud feedback are also likely positive. Calculations of short-term cloud feedback in climate models yield a similar feedback. I find no correlation in the models between the short- and long-term cloud feedbacks.

    http://science.sciencemag.org/content/330/6010/1523

    Second: An Analysis of the Short-Term Cloud Feedback Using MODIS Data

    Abstract: The cloud feedback in response to short-term climate variations is estimated from cloud measurements combined with offline radiative transfer calculations. The cloud measurements are made by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite and cover the period 2000–10. Low clouds provide a strong negative cloud feedback, mainly because of their impact in the shortwave (SW) portion of the spectrum. Midlevel clouds provide a positive net cloud feedback that is a combination of a positive SW feedback partially canceled by a negative feedback in the longwave (LW). High clouds have only a small impact on the net cloud feedback because of a close cancellation between large LW and SW cloud feedbacks. Segregating the clouds by optical depth, it is found that the net cloud feedback is set by a positive cloud feedback due to reductions in the thickest clouds (mainly in the SW) and a cancelling negative feedback from increases in clouds with moderate optical depths (also mainly in the SW). The global average SW, LW, and net cloud feedbacks are +0.30 ±1.10, −0.46 ±0.74, and −0.16 ±0.83 W m−2 K−1, respectively. The SW feedback is consistent with previous work; the MODIS LW feedback is lower than previous calculations and there are reasons to suspect it may be biased low. Finally, it is shown that the apparently small control that global mean surface temperature exerts on clouds, which leads to the large uncertainty in the short-term cloud feedback, arises from statistically significant but offsetting relationships between individual cloud types and global mean surface temperature.

    https://journals.ametsoc.org/doi/full/10.1175/JCLI-D-12-00547.1

    Mainstream researchers consider Dr. Lindzen’s theory discredited. After 17 years it is still warming and there is no evidence of an iris effect off setting any of that warming. None. But apparently that’s not convincing enough for Victor. Apparently Lindzen’s objections have not been convincingly refuted. Although not a physicist, he knows better. Climate is complicated.

  33. 283
    Killian says:

    I do not usually jump into these threads, but illogical reasoning/claims is a pet peave.

    #274 Victor said …strictly speaking I see no need to answer your question since the burden of proof is on the one who poses the hypothesis, not the one who challenges it.

    This is false. If the critique is invalid, it only serves as an ideological/political ploy.

    Moreover, if your position is full of holes, as I believe it is

    I suppose you mean “think,” but perhaps you really think belief trumps knowing and analysis, which might be the whole problem for you.

    Nevertheless, I CAN present a list of certain pieces of evidence that would go a long way to temper my skepticism. If a clear correlation between global temperatures and CO2 levels could be established without the need for invoking special circumstances

    If you deny reality from the get-go, you are already lost. Starting from a false premise leaves little hope of arriving at legitimate answers.

    I know others have pointed this out. That CO2 level affects temps is not in dispute. It simply is not. The science is sound and cannot be legitimately questioned. Ergo, you are either deluded or, truly, are a climate denialist. That is, your objections are not science-based.

  34. 284
    Killian says:

    Faster than expected: Cold melt water effects in the North Atlantic.

    “Until now, models have predicted something for the future … but it was something that seemed very distant,” said Oltmanns, the lead scientist behind the research, which was published this week in Nature Climate Change.

    “But now we saw with these observations that there is actually freshwater and that it is already affecting convection, and it delays convection quite a lot in some years,” she continued.

    One caution is that this is an observational study, not a prediction for the future — and Oltmanns said “nobody really knows” how much freshwater is enough to significantly slow or shut down the circulation, which is technically called the “Atlantic meridional overturning circulation,” or AMOC. Still, it suggests that key processes that have raised long-standing concern are already happening.

    Anyone got a little hysteresis lying around?

  35. 285
    Marco says:

    Victor, your last paragraph comes down to “please show me that your theory *also* works when you ignore various known confounding issues”. That’s a scientifically untenable position, but not unexpected from a dismissive.

  36. 286
    Astringent says:

    Victor @274 – (and for someone who has said everything he doesn’t half rabbit on…) in summary.

    1. Climate science is complicated. Really complicated.So complicated it’s beyond human understanding.
    2. I could be persuaded to change my views if you could just remove all the complication.
    3. But I won’t ever be persuaded because see point 1).

    (and I know you shouldn’t wrestle pigs…)

  37. 287
    Brian Dodge says:

    Killian – I don’t understand your question, but perhaps this will help(especially some lurkers who have forgotten the things they learned in high school physics about Isaac Newton and falling apples).
    v = a * t [velocity = acceleration * time]
    so, after ten years, rate of rise of sea level will have increased to
    0.17mm/yr^2 * 10yr = 1.7mm/yr; the rate at 20 years will be 3.4mm/yr, or roughly the rate in 2009 – so 2009 is ~ year 20
    2100 will be year 111, and the rate will be 18.9mm/year.
    d = a/2 * v^2 [distance = acceleration/2 * time^2]
    so, after 111 years, in year 2100 the distance sea level will have risen will be => 0.17/2 * 111^2 = 1047mm or about a meter.
    All these calculations presume that the 0.17mm/yr^2 remains constant for the next 82 years. Let’s assume that the acceleration accelerates, so that the effective exponent becomes 2.1, instead of 2; that

    would roughly be the equivalent of the 0.17 growing by 0.00092 each year. in that case, sea level rise by 2100 is 1.6 meters.
    There are indications from observations and modelling that changes in the acceleration may already be occurring. http://rspa.royalsocietypublishing.org/content/466/2118/1597
    “Our results indicate that unstable retreat of the grounding line over retrograde beds is a robust feature of models that evolve based on force balance at the grounding line. We conclude, based on our simplified model, that unstable grounding-line recession may already be occurring at the Pine Island glacier.”

  38. 288

    Victor, #274–

    If a clear correlation between global temperatures and CO2 levels could be established without the need for invoking special circumstances; AND it could be established that sea levels have been accelerating in tandem with the acceleration of CO2 levels, again without the need for special pleading such as the invocation of Mt. Pinatubo’s eruption…

    Which is as much as to say that if a model could accurately represent a phenomenon while failing to represent essential factors modulating that phenomenon in reality, then you’d be at the barest start of being willing to consider the possibility that mainstream science is correct.

    “I gave my love a cherry…”

    Yet the riddles all have answers, and people have presented them to you, repeatedly. Invariably there is another rationalization, or simply another refusal to comprehend.

    This is, I fear, truly a ‘story without an end’… though the larger story will inevitably leave you behind–and indeed is already doing so now.

  39. 289
    CCHolley says:

    Victor @274

    There are only two ways to disprove AGW

    First what do we know without question?

    It has been warming. This is indisputable. Glaciers are melting, arctic ice declining, permafrost thawing, humidity has increased, growing seasons lengthened, sea levels rising, and species are migrating poleward and upward. The temperature record confirms this regardless of *adjustments* as even the raw data shows warming. To deny warming is pure denial. None of the *respected* contrarian scientists deny that it is warming.

    CO2 is a greenhouse gas and adding more to the atmosphere changes the radiative balance of the planetary system by slowing heat loss to space. CO2 levels in the atmosphere have been rising and that CO2 is the result of the burning of fossil fuels.

    None of the *respected* contrarian scientists deny that CO2 changes the radiative balance by slowing het loss to space nor that it is increasing as the result of man’s activities.

    Although Victor likely denies it because it is *complicated*, the physics show that the minimum sensitivity to the addition of CO2 to the atmosphere with the water vapor feedback is at least 2 degrees celsius.

    We also know that the warming that is occurring is the result of diminished heat loss to space because increased heat into the system would not result in nights warming faster than days, winters warming faster than summers, and the arctic warming faster than the lower latitudes. Only inhibiting heat loss can result in these observations.

    To show AGW is not real or not significant one would simply have to show two things.

    1. That the net of all feedbacks is enough to off-set the warming resulting from the radiative imbalance created by CO2 and water vapor.

    2. That there is another explanation for the observed warming. Of course that explanation would have to conform to physical laws and be supported by evidence. And being picky, that cause of warming would also have to support the observations of warming nights, winters and arctic.

    The only hypothesis presented to show the possibility of a significant negative feedback is Lindzen’s iris effect. The effect is not supported by observations nor does the hypothesis pass the rigors of scientific review. So far, fail.

    None of the *respected* contrarian scientist have provided an alternative cause of warming that is supported by the evidence and/or the physics. Claims of increased solar irradiation do not stand up to observational evidence nor does it explain the warming nights, winters and arctic. Natural variation is not supported by evidence nor is it supported by physical laws, significant increases in temperatures require either increase in energy or decrease in energy loss. Both the oceans and atmosphere are warming so a redistribution of heat cannot explain most of the warming. Alternative natural causes, so far, fail.

    Of course Victor will never accept the science. This can be seen in the silly evidence he puts forth required to temper his skepticism (denalism actually).

    ”If a clear correlation between global temperatures and CO2 levels could be established without the need for invoking special circumstances”

    This correlation has been shown to Victor countless times without invoking special circumstances. Yet he continues to deny it. After all as Victor has claimed, climate is complicated, expecting to easily visually see correlations in noisy data is a ridiculous expectation. Statistical tests for correlation are well accepted and such absolutely show correlation.

    ”it could be established that sea levels have been accelerating in tandem with the acceleration of CO2 levels,”

    Sea levels rise due to an increase in temperatures that result in melting land ice and thermal expansion of the water. Predicting the response of sea level rise to warming is complex and independent of the question of CO2 warming. Making such a demand of an observation of accelerated sea level rise has nothing to do with the source of warming. To make such a demand is a sign of complete ignorance and lack of critical thinking skills. It is warming and sea levels will continue to rise as a result. Acceleration is a concern, but not an indicator of AGW theory.

    ”if a relatively simple and clear demonstration of the amplification of the greenhouse effect produced by CO2 emissions via positive feedbacks could be presented”

    The demonstration of feedbacks has been demonstrated and explained over and over again. But Victor seems not to be able to find this information. The feedbacks that will be the result CO2 warming are the same feedbacks that would result from ANY warming. When it warms, the air holds more water vapor. When it warms, changes occur with the carbon cycle such as less being absorbed by the oceans, and most importantly, changes occur in albedo due to melting ice and snow. (see ice ages)

    Victor not only admits to being clueless of the physics, he demonstrates his complete cluelessness.

  40. 290
    prokaryotes says:

    Arctic Permafrost Thaw Looks Alien, Accelerates
    https://www.youtube.com/watch?v=FCoo8MA4eI8

    The trend from frozen tundra soils shifting to thermokarst erosion and thaw ponds, may in the future be exacerbated by increased rainfall and extreme weather events. http://onlinelibrary.wiley.com/doi/10.1002/lol2.10063/epdf and http://www.inrs.ca/english/actualites/thawing-permafrost-causing-browning-northern-lakes

    Are there efforts to add heterotrophic feedbacks to climate models?

  41. 291
    Victor says:

    I must say I am impressed, and even touched, by the very sincere efforts of those posting above to convince me that I’m on the wrong track. Aside from the odd ad hominem tossed in from time to time, your arguments strike me as intelligent and for the most part reasonable expositions of the thinking behind the AGW paradigm. It all sounds reasonable enough, but as I (and many others more qualified than I) see it, you are failing to accept that certain fundamental problems exist in the prevailing view and will not go away simply because you deny their existence and minimize their importance.

    Some examples:

    If a steady increase of CO2 levels causes global temps. to rise, then how do we explain the lowering and/or leveling off of global temps. during the period ca. 1940-ca. 1979? This is roughly 40 years without significant warming, surely not a short-term bit of random “noise.” Yet AGW advocates claim that the doubling of CO2 levels will invariably, due to iron clad physical laws, result in 2 degrees (or more) of global warming. Since this is the period during which the burning of fossil fuels really took off, it’s hard to see any evidence of such a relationship. This in itself strikes me as strong evidence for falsification. Not to mention that the strong upward trend in temperatures at the end of the 20th century leveled off considerably during the first 15 or 16 years of the 21st, a period when CO2 levels were soaring.

    When we compare the steady rise in sea levels over the 20th century with the steady rise in CO2 levels, it does look like a pretty convincing correlation, yes. However, and regardless of what caused it, the lowering/leveling of global temps. during the same 40 year period cited above apparently had no effect on sea levels, which continued to rise regardless. How then can we infer an effect on sea levels produced by a much briefer and far less intense cooling period caused by the Pinatubo eruption? And what about all the other major eruptions during the 20th century? CC Holley has attempted to downplay the importance of sea level acceleration, but the fear of precisely this sort of event being caused by continued CO2 emissions is one of the principal “selling points” of the climate change paradigm.

    Roger Pielke, among others, has demonstrated that almost all the incidents of extreme weather we’ve been experiencing lately are not unprecedented and that there is indeed no evidence of long term trends in just about any of these areas. That includes hurricanes, tornadoes, droughts, heat waves, etc.

    I could add more, but you get the idea.

    Bottom line:

    In order to make a case for the sort of drastic reduction in the burning of fossil fuels or any other human causes of CO2 emission, one would have to:

    1. Demonstrate that the recent increases in global temperature represent a true long term trend, despite significant hiatuses both in the 20th and 21st centuries.

    2. Demonstrate that warming in the past tells us that warming will continue into the future, despite the fact that a very similar trend in the opposite direction during the middle of the 20th century convinced so many that we were headed for another ice age.

    3. Demonstrate that the warming we are now experiencing is in fact caused by CO2 emissions and not the result of natural variation. Since the steep rise in CO2 during the middle of the 20th century did not heat the earth in any significant manner during that period, it’s hard to see how “the physics” in itself can be used to make such an argument.

    4. Demonstrate that the relatively modest increase in global warming that is now anticipated by AGW alarmists is necessarily harmful.

    Extraordinary claims require extraordinary evidence. Sorry, I appreciate your efforts, which are no doubt sincere, but I’m not buying t.

  42. 292
    jgnfld says:

    @291

    3 points among many that could be made.

    1. It is very hard to EVER have an “unprecedented” event. Is is much easier for the rate of very large events to climb or fall.

    2. “So many” were never convinced we were heading into an ice age if you read the literature of the time.

    3. Natural variation has been pretty much ruled out for a number of effects, particular temperature. What is an “extraordinary claim” requiring “extraordinary evidence” to say natural variation is causing warming.

    With respect to this last, isn’t it just wonderful when a denier lectures professionals about 1st year science. I bet when he goes to the ball park he yells out: “You need to keep your eye on the ball!” to each and every player.

  43. 293
    MA Rodger says:

    Victor the Troll @291.
    We know you have cloth ears so let us take this slowly. (Of course we two have probably been round this particular block before, perhaps even more than once, but you do seem to need the extra instruction if you are going to progress you out from under your bridge on a more permanent basis.)

    Why are you obsessed with the “burning of fossil fuels” or more broadly the “level of CO2”? The origin of the CO2 molecules floating about in the atmosphere is not of-itself a reason for increasing global temperature. It is increases in the “level of CO2” that impacts temperature but even that doesn’t give the whole story. There are other GHGs to consider and other non-GHG forcings as well.
    So when you say the period “ca. 1940-ca. 1979” was when ” the burning of fossil fuels really took off”, your argument is ignoring the 28% AGW that had be put in motion prior to 1940.
    Or do you have a reason for disputing the 28% pre-1940 AGW forcing (relative to 2011) as set out in IPCC AR5 AII Table1.2? (And note the pre-1940 CO2 forcing is given as 32% of the 2011 value.)

  44. 294
    CCHolley says:

    Victor @291

    I must say I am impressed, and even touched, by the very sincere efforts of those posting above to convince me that I’m on the wrong track.

    No one is trying to convince you. That is a hopeless task. You are a truly deluded denier of the science and your latest response only reinforces that rather obvious conclusion.

    The only reason your posts are responded to is to clarify to curious visitors to this site, those that are interested in the science, that the arguments put forward by science deniers like you are just garbage.

    I posited that to disprove the science, one must show that there is a large negative feedback to CO2 forcing along with an alternative cause of the warming that has been experienced. Anything else is just smoke, a red herring.

    You totally continue to ignore these self-evident truths.

    You have not provided evidence to support the possibility of either case, rather you have regurgitated old tired denier memes that do nothing to change the fact that CO2 causes warming and that there is no plausible alternative to the current warming trend. Relegating the warming to *natural* is not an answer. No *natural* mechanism to explain the warming have been put forth by anyone nor is there any evidence of such. No one. Certainly not you, not Judith Curry, not Spencer, not Lindzen. No one has explained how this could work within the realm of physical laws. No one. Invoking the *natural* alternative is nothing but a specious claim.

    YOU fail once again.

  45. 295
    nigelj says:

    Victor @291 is spamming this website with repetitive denialist propoganda. He is repeating points he has made many times before, and repeating questions that have been well answered many times before.

    He is not adding any genuine,new science based scepticism.

    Moderation policy says do not repeat points made previously. Victor is repeating points endlessly, not to better explain, summarise them, or give context, but for no good reason other than to smam this website.

    For excample, the flat period of temperatures during the middle of last century is easily explained by high particulate emissions and suplphates from industry after WW2 temporarily counter acting the warming from CO2, until pollution controls were gradually added around the 1960’s. This has been explained to Victor before more than once.

    Any well educated person should be able to grasp this, so I have to infer Victors motives are not genuine questioning scepticim, but are driven by some unusual psychological motive or hidden political agenda.

  46. 296

    Victor, of course you’re not buying it. We’ve addressed all the issues you bring up before, to you. If you didn’t listen then, you won’t listen now. You’re pretty much determined not to listen. Why bother going through the exercise again? You’d just blow it off again.

  47. 297
    mike says:

    Moderators: please, can you toss the obvious trolls in the interest of a discussion about the science of climate change?

    There must be a blog somewhere on teaching pigs to sing, can we encourage some squealers to look elsewhere for lessons?

    Thanks

    Mike

  48. 298
    Killian says:

    I hope people will focus some attention on Ch 15 of the CSSR.

    https://science2017.globalchange.gov/chapter/15/

    Some Dessler tweets with Hayhoe comments re sensitivity:

    https://twitter.com/AndrewDessler/status/975170343970263040?s=19

    Risk is yhe key metric.

  49. 299
    Killian says:

    I am responding here only to show how pointless it is. Troll said If a steady increase of CO2 levels causes global temps. to rise, then how do we explain the lowering and/or leveling off of global temps. during the period ca. 1940-ca. 1979? This is roughly 40 years without significant warming, surely not a short-term bit of random “noise.”

    Science said

    https://www.newscientist.com/article/dn11639-climate-myths-the-cooling-after-1940-shows-co2-does-not-cause-warming/

    The mid-century cooling appears to have been largely due to a high concentration of sulphate aerosols in the atmosphere, emitted by industrial activities and volcanic eruptions. Sulphate aerosols have a cooling effect on the climate because they scatter light from the Sun, reflecting its energy back out into space.

    The rise in sulphate aerosols was largely due to the increase in industrial activities at the end of the second world war. In addition, the large eruption of Mount Agung in 1963 produced aerosols which cooled the lower atmosphere by about 0.5°C, while solar activity levelled off after increasing at the beginning of the century

    The clean air acts introduced in Europe and North America reduced emissions of sulphate aerosols. As levels fell in the atmosphere, their cooling effect was soon outweighed by the warming effect of the steadily rising levels of greenhouse gases.

    This is information well-known enough to be considered “common knowledge” among those interested in climate change issues. This is clear dishonesty, and is why engaging these sorts is a waste of everyone’s time. We are past the point of climate trolls being important. We have passed the tipping point WRT public perception and no longer have any gain from this sort of interaction.

    The poll found that 72% of participants agree “that given the amount of greenhouse gases that it produces, the United States should take aggressive action to slow global warming,” while 68% want the US to lead global efforts to slow climate change.

    https://www.globalcitizen.org/en/content/reuters-poll-trump-paris-climate-agreement/

    We must now focus on bettering the science even further and on actions that we must take.

    Note, I was repeatedly banned from RC for calling out climate trolls. I understand the concept. But that era is over. I suggest we move on to building rather than sparring with ghosts.

  50. 300
    Killian says:

    #287 Brian Dodge said Killian – I don’t understand your question

    They give a range of 0.17mm/yr2 +/- 0.05. I was unclear on the “2” so that was part of the problem. More so, I am not a maths guy and do not pretend to be, so always like to check what i think I think with people who are.

    I took the 0.17mm/yr2 to mean .17mm squared each year. That gave me a max of 0.22 squared, or 0.0484 per year rate of increase. No?

    So, if today is 3.3 (last I heard was over 4mm/yr in the most recent years, I believe), then next year would be 3.3484, 2020 = 3.3968, and so on. No?

    Thanks for your work. Appreciated.