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Unforced variations: Sep 2019

Filed under: — group @ 1 September 2019

This month’s open thread for climate science topics. A new two-part community assessment of tropical storms and climate change is online at BAMS: Knutson et al. (2019a ; 2019b). And for those interested in Arctic Sea Ice, there is always the NSIDC.


  1. T. Knutson, S.J. Camargo, J.C.L. Chan, K. Emanuel, C. Ho, J. Kossin, M. Mohapatra, M. Satoh, M. Sugi, K. Walsh, and L. Wu, "Tropical Cyclones and Climate Change Assessment: Part I: Detection and Attribution", Bulletin of the American Meteorological Society, vol. 100, pp. 1987-2007, 2019.
  2. T. Knutson, S.J. Camargo, J.C.L. Chan, K. Emanuel, C. Ho, J. Kossin, M. Mohapatra, M. Satoh, M. Sugi, K. Walsh, and L. Wu, "Tropical Cyclones and Climate Change Assessment: Part II: Projected Response to Anthropogenic Warming", Bulletin of the American Meteorological Society, vol. 101, pp. E303-E322, 2020.

278 Responses to “Unforced variations: Sep 2019”

  1. 51
    MA Rodger says:

    RSS has posted for August with an anomaly of +0.68ºC, not much different Julys’s anomaly (as per UAH). It is the 3rd warmest August on the RSS TLT record (4th on UAH), putting it behind August 2017 (+0.74ºC) and 2010 (+0.69ºC) while ahead of 2016 (+0.67ºC), 1998 (+0.61ºC), 2015 (+0.61ºC), 2018 (+0.51ºC) and 2001 (+0.47ºC). August 2019 was 33rd in the RSS all-month record (43rd in UAH).

    The year is now two-thirds done and 2019 is looking a very strong candidate for 2nd-place in the full calendar year RSS TLT ranking. To drop to 3rd would require the remainder of the year to average +0.56ºC, a level of cooling relative to Jan-Aug that hasn’t occurred in the RSS record outside strong El Nino years (1983, 1991, 1998, 2007, 2010, 2016). (The trend-defying UAH TLT record puts Jan-Aug 2019 in 4th position and not so far ahead of a possuble 5th-place for the full calendar year.)

    …….. Jan-Aug Ave … Annual Ave ..Annual ranking
    2016 .. +0.86ºC … … … +0.79ºC … … … 1st
    2019 .. +0.71ºC
    2010 .. +0.68ºC … … … +0.62ºC … … … 3rd
    1998 .. +0.67ºC … … … +0.58ºC … … … 5th
    2017 .. +0.63ºC … … … +0.66ºC … … … 2nd
    2015 .. +0.53ºC … … … +0.59ºC … … … 4th
    2018 .. +0.52ºC … … … +0.52ºC … … … 6th
    2005 .. +0.46ºC … … … +0.46ºC … … … 8th
    2014 .. +0.46ºC … … … +0.47ºC … … … 7th
    2007 .. +0.46ºC … … … +0.41ºC … … … 10th
    2002 .. +0.42ºC … … … +0.39ºC … … … 12th

  2. 52
    MA Rodger says:

    Nicholas O @40,

    The idea that Sea Level Rise could be used as a measure of AGW, as if the oceans were a giant thermometer is not an entirely fanciful idea but it is far from accurate-enough to demonstrate that over a few years the oceans were warmed rather than the surface being warmed.

    Most of the global warming energy ends up in the oceans and Ocean Heat Content would present a better measure than Sea Level Rise. There are still many measurement issues but perhaps the main problem (as with SLR) is that any surface warming that is negated by extra Ocean warming will be a very small component within the overall Ocean Heat Content rise.

    And while Ocean Heat Content is the big recipient of AGW, there is also ice-loss which, energy-wise, is of a similar magnitude to the surface warming and hasn’t run at a nice constant rate decade-to-decade, although the measurement problems are perhaps less difficult.

    Plus to consider all the energy flows, there is the increasing energy flux out into space as the planet warms. Again, this does not provide a nice unvarying value into the mix and is a very diffiuclt to measure accurtely decade-by-decade.
    And climate forcings are another area of uncertainty.
    This SkepticalScience webpage shows the relative size of all these considerations.

    Of course, your enquiry concerns the idea that “models and theory” are out of step with actual surface measurements. The usual denialist blather is that such an idea is true. But, bearing in mind these denialists are hardily the most relable of witnesses to anything, is it true? Are “models and theory” suggesting a stronger warming?
    For surface warming, this RealClimate webpage suggests otherwise. (The graphics are updated to include 2018 and 2019 is looking to end up as the second warmest year on record.)

  3. 53
    zebra says:

    #47 Kevin McKinney,

    See #46.

    Either both you and KIA accept that CO2 has caused a substantial increase in climate system energy, or you don’t.

    If we begin with the premise that there has been an increase in energy, then we can certainly attribute Dorian’s characteristics to that increase. As I pointed out on a couple of the attribution threads, the probability of Dorian (or some other event) occurring as it did absent that energy difference is essentially zero.

    So, to have a rational discussion… a debate, if you like… you and KIA have to come to an agreement before you can disagree. If KIA doesn’t initially agree that CO2 has caused an increase in the energy system, then it is pointless to be comparing factoids and statistics as you are.

  4. 54
    alan2102 says:

    #12 Dominik Lenné 4 Sep 2019: “– Vegetation growth. –
    Could please someone with the expertise make the following clearer:
    On the one hand, we have still vegetation taking up a considerable part of human CO2 emissions. This implies growing biomass. [1]
    On the other hand, it has been shown by satellite analysis, that vegetation is actually shrinking because of higher air dryness.[2]
    Can somebody get it right? Can it be, that vegetation area is decreasing while overall photosynthesis is still increasing?

    Great questions!

    That second link has been open in my browser for weeks. I’m trying to square it with the reported greening described here (scroll down to 2nd item):

    Growing biomass has not just been “implied”, it has been demonstrated compellingly. The item cited in the above is just one recent one, of many. This is a well-documented trend.

    So, what gives? Comments welcome.

  5. 55
    Ray Ladbury says:

    Mr. KIA@50
    Wrong as usual. We’re up to Gabrielle.

    And of course the science is always open to question–just not by complete an ignoramus with no grasp of the science. That means if you haven’t published in the field, maybe you should focus on learning, rather than correcting the experts.

  6. 56
    Martin Smith says:

    Has there been any new findings about the effect of cosmic rays on climate? I’m seeing Svensmark’s “theory” being pushed by the “skeptics” again.

  7. 57
    Nemesis says:

    @Mr Know It All, #50

    ” 42 – Nemesis
    “ Does Nature discuss anything at all?

    No, she doesn’t discuss anything. Enjoy your awareness of Nature and her undefeatable laws ect you attained along the road, no one can take that away from you, enjoy your life, enjoy yourself.”

    That’s exactly what George Carlin said:

    Sorry, I Know It All, smile:

    ” Carlin is often revered by conspiracy theorists (mainly the libertarian Illuminati/Truther Ron Paul variety) because of a scathing piece he performed in his later years, in which he says, among other things, that politicians exist to give the illusion of freedom of choice, and his questions regarding 9/11. Strangely enough, Carlin himself was center-left and never outright said that the U.S. government perpetrated 9/11, so we guess that he must have been a puppet of the Illuminati, and not the hero the cranks make him out to be?

    One of Carlin’s later routines on environmentalism was highly critical of the “…self-righteous environmentalists, these white, bourgeois liberals…” for their self-important veneer of altruism and denial of the fact that what is at stake is not the planet’s mere existence, but the planet’s habitability for them and other living things. Predictably, his message went over the heads of climate deniers, who took the video as evidence that he agreed with them, gleefully reposting it on YouTube under such dishonest titles as “George Carlin on global warming”. Their efforts are rather undermined by the total absence of any talk of global warming in the video, and the fact that Carlin has elsewhere acknowledged its existence and criticized humans for ravaging and not caring about the environment…”

    Btw, I asure you, Mother Nature will kick ass of the white bourgeois right-wing clowns resp the fossil fool induced climate heating deniers as well and, like I said, she will not discuss any shit by then and I do really love that 38) Just a reminder:

    I’m an anarchist, I don’t vote for any funny party. Politics is a business driven by the economy resp the military-industrial complex, politics is a show business made up to disguise reality.

    Over & out.

  8. 58
    Mal Adapted says:

    Mr. Ironically Anosognosic Typist:

    So, everyone should accept CC scientists claims without question? Noone can question CC science?

    Mr. IAT is straw-manning again. Genuine experts will satisfy themselves of the case for AGW. Non-experts who refuse to accept the overwhelming consensus of actual experts, albeit tentatively and provisionally as the experts do themselves, are merely the pathetic victims of the Dunning-Kruger Effect. And of course questions may be asked, though only those asked in good faith deserve answers. Arguments from logical fallacies and fabricated ‘facts’, or from sheer willful ignorance, do not.

  9. 59
    Tom Dayton says:

    TRM (

    Also see And Then There’s Physics… “Propagation of Nonsense”

    …and “Propagation of Nonsense Part II”:

    And in WTFIUWT, if you have the stomach for it, search for Nick Stokes’s comments.

  10. 60
    Tom Dayton says:

    TRM: In particular, in ATTP’s “Part II,” see Nick’s comment of Sept. 11, 2:16 a.m.:
    “Yes, that is the problem with these random walk things. They pay no attention to conservation principles, and so give unphysical results.”

    “But propagation by random walk has nothing to do with what happens in differential equations. I gave a description of how error actually propagates in de’s here. The key thing is that you don’t get any simple kind of accumulation; error just shifts from one possible de solution to another, and it then depends on the later trajectories of those two paths. Since the GCM solution does observe conservation of energy at each step, the paths do converge. If the clouds created excess heat at one stage, it would increase TOA losses, bring the new path back toward where it would have been without the excess.”

  11. 61
    Tom Dayton says:


    Generalizing from Nick’s comment: As commenter “See — owe it to Rich” pointed out ( Pat Frank’s linear equation sort of accurately reproduces the mean of the GCM model runs, but not any individual model run. Nor does it reproduce the variability around the mean of the model runs.

    Pat Frank’s linear equation is not a substitute for GCMs, in any regard except as a rough estimate of the model means!

  12. 62
    nigelj says:

    MR KIA says “So, everyone should accept CC scientists claims without question? Noone can question CC science?”

    Anyone should question cc science, because that is basic healthy scepticism, but it doesn’t entitle people to endless deliberate stupidity, when simple evidence based things have been explained to them. And not knowing the difference between healthy scepticism and deliberate stupidity is itself deliberate stupidity.

  13. 63
    MA Rodger says:

    alan2102 @54,

    You are perplexed that Yuan et al (2019) is suggesting that the plants are taking up less atmospheric CO2 due to increasing atmospheric water vapour pressure deficit (VPD) in a warming world yet we often hear (indeed them denialists shout it out) that plants are taking up more atmospheric CO2 as CO2 levels rise.

    Plants are indeed taking up more CO2 as CO2 levels rise. The various studies examined by the Global Carbon Project lead them to report some 3Gt(C)/year net is being taken from the atmosphere and that this value has been increasing steadily over the period 1959-2017 at something like 0.37Gt(C)/year/decade. There is no sign of any slowdown since 2000.
    Also reported by the GCP is the Land-Use-Change carbon flux which reduces the carbon sink into the biosphere by about 1.5Gt(C)/year.

    And within all those numbers there is the finding of Yuan et al (2019).

    “A machine learning method [i.e., random forest (RF)] was used to reconstruct NDVI(Vegitation Index) based on atmospheric [CO2] concentration and five climate factors (air temperature, precipitation, radiation, wind speed, and VPD) over the last 34 years in each pixel (fig. S7) and then model experiments were applied to separate the impacts of VPD as well as of other variables (see Materials and Methods). Globally, the model experiments suggest that the atmospheric CO2 concentration, air temperature, and VPD are the most important contributors for the variability of NDVI (fig. S8A). Rising VPD was found to significantly decrease NDVI, indicated by the larger negative NDVI differences from 1999 to 2015, suggesting that substantial increases of VPD strongly limited NDVI (fig. S8B).”

    So they find CO2 levels and temperature both increase CO2 draw-down by plants but VPD acts the other way. The continuing net uptake of CO2 by plants suggests that VPD has not overwhelmed the increase in CO2 draw-down due to CO2 and ΔT.
    The paper’s Fig 6 puts some numbers on the VPD effect which appears to be large in Fig6c, perhaps halving the CO2 draw-down over the period 1999-2015. Time will tell whether such a finding is controversial.

  14. 64
    Chuck says:

    Killed In Action says – “So, everyone should accept CC scientists claims without question? Noone can question CC science? OK, got it.”

    No, you don’t got it and you’ll never get it. You can’t even follow a simple trend line when it comes to hurricanes. Better get out your Sharpie and start doctoring your maps and charts so you can fool your friends.

  15. 65

    zebra, #53–

    …then it is pointless to be comparing factoids and statistics as you are.

    I certainly don’t assume that a rational discussion will ensue. However, my experience over the years has led me to believe that it is better not to leave fallacious ‘talking points’ unrebutted.

    In this case, the essential point is that there is clear evidence that tropical cyclones in the Atlantic have indeed become stronger, even as overall hurricane frequency has not changed much. We saw that in the papers I cited previously, and it’s very clear even in the informal ‘factoid’ I presented to KIA.

    The corollary, of course, would be that while a Dorian could have happened in 1935, when the “Labor Day” hurricane hit Cat 5, the odds of it happening in 2019 are in general a hell of a lot better. If I may be forgiven a little bitter sarcasm, I guess I could say that the Bahamas really hit the jackpot.

    The official count of Bahamian fatalities is now 50 dead, but that’s apparently still way behind the reality. And then there’s the exodus of storm refugees and the general disruption, plus this:

    “Given the storm surge and significant flooding from the hurricane, it is likely that some bodies may have washed out to sea,” said Esther Mary de Gourville, the World Health Organization’s representative to the Bahamas. “The exact death count may never be known.”

    I’m wondering how complete Abaco’s recovery will be; Marsh Harbor only had about 6,000 residents to begin with. It will be a long time before it’s ready to support that many, I suspect. I note that while New Orleans has in some sense recovered from Katrina–and from a couple of stays there, it’s a functioning, vibrant city, albeit with ongoing problems–its population still has not quite recovered to 2000 levels. And there’s compelling economic and social reasons for New Orleans to exist; Marsh Harbor, maybe not so much.

  16. 66

    KIA, #50–

    OK but on 9/5/2005 the alphabetically named hurricanes were up to Katrina; on 9/5/2019 they were only up to Dorian.

    We were talking Cat 5s. So now you want to change the subject to hurricanes in general?

    OK, fine.

    The mainstream science says that overall frequency of hurricanes is not likely to change much, and in fact seems not to have changed much. Hurricanes have gotten stronger on average, and move slower on average, but are not more frequent on average.

    So your point was what, exactly?

  17. 67

    KIA, #50–

    And then there’s those pesky facts; those 8 Cat 5s occurred from 1924 to 1938.

    That would indeed be a “pesky” fact if anyone were arguing that Cat 5s were a new thing. But as they ain’t, it ain’t, either.

    Reminder: the actual argument is that Cat 5s are now much more likely than they used to be–which is pretty irrefutable on the data.

    Care to try again?

  18. 68

    Martin Smith asks:

    “Has there been any new findings about the effect of cosmic rays on climate? I’m seeing Svensmark’s “theory” being pushed by the “skeptics” again.”

    Rex Fleming, retired from NOAA, has this recent book including a chapter on cosmic rays

    Also Gerald Browning, retired from NCAR has this

    “The follow on manuscript that I have submitted to Dynamics of Atmospheres and Oceans is under review. It mathematically proves that climate and weather models are based on the wrong set of continuous equations. If it is accepted I will reference it. If not I would like to post it here” (Climate Audit)

    One can always find something new, the question is whether any of it is valid.

  19. 69
    nigelj says:

    MAR @45 says “DeSmogUK is reporting that some swivel-eyes denialists have written a letter to be sent to the EU, and also the UN. In it they claim that:-….(assorted silly stuff)”

    I saw quite a good response to this on another website : “You would think the authors of this letter might feel foolish regurgitating these stale , long debunked myths. But then, I suppose it’s difficult to understand what they’re paid not to. “

  20. 70
    zebra says:

    #65 Kevin McKinney,

    “However, my experience over the years has led me to believe that it is better not to leave fallacious ‘talking points’ unrebutted.”

    Putting aside your unspecified “better”, the problem is that you have not established what the talking point is that you are “rebutting”. To do that, you would have to establish, in conjunction with KIA, what you agree about, before you can have a disagreement.

    I posed a simple question, and you, like KIA, don’t seem to want to answer it:

    Does increasing CO2 increase the energy in the climate system?

    If yes, then, as I explained, there is no question about attributing Dorian to that increase in CO2. But, you clearly don’t want to establish that position with KIA beforehand… perhaps because, as I have suggested in the past, it would take away the fun of doing the same repetitive ritual recitation of mutual non-sequitur. Habits are hard to break.

  21. 71
    Nick O. says:

    # 46 – Zebra
    You said of my post at #40:

    “[this] …really drives me crazy at this point.”

    My apologies for driving you crazy; that was not my intention! You then – rightly – ask me:
    “If you already accept that the system energy is increasing, then why do you feel the need to ‘prove’ it by “statistically significant sea level rise”?”

    Well the point here is the word ‘you’, meaning me, in the context of these sentences and questions.

    I myself do not doubt that the climate is warming and that humans are largely responsible. However, when I am talking to someone who does not have a scientific background, and who is genuinely skeptical about global warming but not vexatiously so, I need to have some useful arguments to help counter some of the nonsense put out by the climate change skeptics.

    What am I to do, in this situation?

    So, as an example, if my interlocutor points out that the ‘climate’ has not warmed as much as was predicted by theory and models, what answer must I give? One response is simply to say that the models are not wholly correct and there is always going to be error, but I am not sure that that is on its own a helpful response.

    I think a better response is to try to argue, as I was alluding to in my post at #40, that if the heat is being trapped in the system (it is), and it is not being shown up as much as predicted in the climate (atmospheric) models (depends how one looks at the observations, but there is a rising trend, regardless), then the heat must be being trapped elsewhere in the Earth system. Hence my thought that it is going into the oceans, which must therefore be warming more quickly than allowed for, and that warming should, ceteris paribus, lead to thermal expansion of the seas and a faster rate of sea level rise.

    I then went on to ask whether my approach was correct (roughly) or wrong, and if correct, what data are there to back up my statements.

    That was the point I was trying to get at. Was I wrong?

  22. 72
    Nick O. says:

    #52 – MA Rodger

    Many thanks for the reply to my post at #40, which was helpful, although it did not add much to what I knew already.

    I am not trying to convince ultra skeptics; rather my main concern is when talking to someone who does not have scientific training but is genuinely skeptical, although not vexatiously so.

    For example, during the so-called global warming ‘pause’ – remember that? – I was dining with someone who asked me about it and what my thoughts were. I said that the ‘pause’ was nothing of the kind, and that if the heat was not being trapped in the atmosphere it was going into the oceans, where it would in turn lead to more melting of sea ice and also some thermal expansion. I went on to predict that this would probably lead to an acceleration – small but detectable – in the rate of sea level rise.

    I suppose I should also have said that it would be some years before the observations would be able to confirm or support my contention. It seems that that is still the case, but it is only a matter of time before such confirmation is possible, I think.

    Thank you again.

  23. 73
    Simon C says:

    Kevin McKinney @65 – A very good point about Marsh Harbour, AKA “The Mudd” or “The Mud”. The main occupancy here as I understand it was by Haitian refugees and the whole area has long been historically vulnerable to flooding (as the different names imply.) It is fairly disgraceful that so many people were left to live in improvised buildings in an area of known vulnerability. Jeremy Purseglove has written about this in his book “Working with nature”. No doubt there are problems in finding alternative accommodation areas, and persuading people to move to them. But sometimes those nettles have to be grasped by the relevant authorities, and no doubt will have to be grasped ever more firmly, as the planet unfolds (without discussion) its response to our lethal loading of the atmosphere.

  24. 74
    Mal Adapted says:

    A morsel of meliorative news today, however meager: William Happer is leaving the National Security Council. Trump had installed Happer, a career physicist-for-hire emerging from the George C. Marshall Institute, on the NSC to lead an iteration of the infamous ‘red team’ proposal, a transparent stratagem to discredit climate science initially proposed by Scott Pruitt — remember him 8^)?

  25. 75
    Al Bundy says:

    Adam Lea; I don’t think there is much point. Once you get to category 5 you are looking at catastrophic destruction. Adding a category 6 appear to offers no extra value, it is essentially the same catastrophic destruction.

    AB: A very useful category 6 would begin just above the most powerful hurricane or typhoon in history. Colloquially, these storms can be called “Anthropomorphic Cyclones”.

  26. 76
    Nemesis says:

    Addendum to my comment at #42:

    IF there is any future at all beyond currently dying capitalism, then it will be a future without funny money, hehe :))

    Auroville, the first off-grid sustainable city without funny money:

    All discussions and all piling up of data and endless numbers are futile without massive and instantaneous acting (hear, hear: Bye, bye, funny capitalism^^)– that sounds mundane, but comes with infinite impact for good or bad.

  27. 77
    mike says:

    I recently became curious about any acceleration in global warming but on searching the internet with google for ‘global warming acceleration’ I found very little of substance. The links below and a few stories arguing it was not accelerating from the usual suspects. Given all the fuss about a pause over the last 10 years it is rather odd to find so little from scientists about the fact that the opposite is happening.

    I did find this comment in Nature from Dec 2018.
    Global warming will happen faster than we think. Yangyang Xu, Veerabhadran Ramanathan and David G. Victor.

    And last months
    U.N. Chief Warns of Acceleration of Climate Change.

    And a passing comment in Global Warming Science | Union of Concerned Scientists

    So I have had a go myself and as far as I can tell warming has clearly been accelerating since about 1960 on average at about 0.04 C/decade^2.

    Normally we estimate the trend using 30 years of data. For GISS this is 0.21 +/- 0.058 C/decade according the SkS trend calculator. However if there is acceleration we need to add 0.04 x 1.5 to this to get a current estimate. ie 0.27 C/decade, a fair bit higher any values I have seen quoted for the current rate of warming.

    As far as I can tell this result is consistent across all data sets. I looked at GISS, HADCRUT, BEST, UAH and RSS. Despite RSS and UAH only starting in 1979 but they show signs of an acceleration that can be extrapolated backwards to an origin about 1960 in line with the other sets. The acceleration seems to have been stronger before 1980 and less since then; about 0.025 to 0.035 C/decade^2. Perhaps this was due to the air clearing from volcanic and industrial aerosols.

    Extrapolating current trends with an acceleration included indicates 4 C or more of warming by 2100. Which appears to be roughly in line with the models and the higher RCP scenarios.

    I’ve seen articles on sea level acceleration and recently Tamino covered methane. Plenty about accelerating CO2 emissions. But nothing on accelerating temperature.

  28. 78
    zebra says:

    #71 NickO,

    I hope you understand that I was not referring to you specifically, but to a pattern of interaction. (See my recent comments to Kevin.)

    To answer your question: Yes, I think it is wrong to respond like that. I base this on my own teaching experience, and observations of many comment threads here and elsewhere.

    When a ‘student’ is having trouble with a concept, you have to first find out what the student isn’t having trouble with… where are they starting from? If you are having a ‘scientific debate’, as I said to Kevin, you have to establish what you agree about so you can know what it is you disagree about.

    So, if you think you really do have a sincere interlocutor, then you should ask questions, not give answers. You may learn that the person is not serious, as with the Denialists you see here. But, the point is to know what the person is actually understanding… before you start ‘splaining.

    If someone says “there is a pause in GMST”, the proper answer is “so what?”.

    How do you think the person you were talking about would have answered?

  29. 79

    #70, zebra–

    I’m really not sure who appointed you to referee conversations in general… however, if it makes you happy:

    Yes, of course increasing CO2 (and other GHGs) increase energy in the climate system.


  30. 80
    Chuck says:

    Kevin McKinney – Care to try again?

    >Don’t say that to K.I.A.! He’ll think you’re serious.

  31. 81
    Mal Adapted says:


    I recently became curious about any acceleration in global warming but on searching the internet with google for ‘global warming acceleration’ I found very little of substance…Given all the fuss about a pause over the last 10 years it is rather odd to find so little from scientists about the fact that the opposite is happening.

    Thanks for bringing this up, mike, I’m curious about it too. My naive impression is that the trend of GMST is in fact accelerating. Like da paws, however, it needs to be shown by appropriate statistical methods, at which point I’m admittedly over my head. My crude test was simply to compare the per-year slope of GMST for four 30-year intervals between 1960 and today, using the SkS (Kevin Cowtan’s, actually) trend calculator with the GISTEMPv4 dataset:

    1960-1989: 0.0134+/-0.0061 (2σ)
    1970-1999: 0.0173+/-0.0064
    1980-2009: 0.0173+/-0.0062
    1990-2019: 0.0223+/-0.0063

    That’s strongly suggestive, but hardly definitive. My next attempt would be to use yearly rolling trend values over the same 60 years and run a linear regression, but that would be little more than mathturbation given my limited knowledge. IMHO this is a job for someone with Tamino’s level of expertise. Still, I’m a little surprised no one’s done it yet.

  32. 82
    nigelj says:

    Zebra @53 and @70 has been going on about agreeing on basic issues and definitions when debating with climate denialists, and not just throwing factoids at each other and talking past each other. I couldn’t agree more in theory, but the problem is that sort of teacher / pupil discussion and asking of questions etc requires a great deal of back and forth discussion, which is very time consuming.

    I think we do the best we can with the time we have, and so sometimes responses to denialists take the form of ‘lectures’ with a lot of lists of facts . This will probably only convince a small number of denialists, but its worth a go, but it may go further to convince more open minded observers who are lurking around and I’ve seen some evidence of this .

    And even if you get a climate denialist to agree that more energy in the system must have some effect on a hurricane like Dorian, (which it must of course) the denialist will dodge and weave and want proof its a ‘significant effect’ or alternatively isn’t just sending hurricanes further offshore on another track etcetera, so we are back to discussing ‘factoids’, like the historical data KM mentioned, or what the climate models predict will happen.

    I can’t really see whats wrong with discussing factoids, because things always come back to facts. But I agree with Zebra its good to try to clarify definitions and get some agreement on basics early in discussion, if possible, just that this is hard to do in an ideal way outside of a classroom.

  33. 83
    S.B. Ripman says:

    Mike #77: Thanks for keeping our attention focused on the important things: CO2 keeps going up without abatement, and temperatures are rising at an accelerating pace. Greta Thunberg is correct: the house is on fire and the adults are sleepwalking. Those who are, and have been for the last 30 to 40 years, complicit in denying the science, complicit in furthering BAU, even in the face of verifiable climate predictions by panels of respected professionals, will be viewed as despicable criminals (or blithering idiots) by future generations.

  34. 84
    Al Bundy says:

    AB: A very useful category 6 would begin just above the most powerful hurricane or typhoon in history. Colloquially, these storms can be called “Anthropomorphic Cyclones”.

    AB: Note that “6” ties in with the sixth mass extinction and 666. Lots of stuff can be tied in so as to steer the zeitgeist. Note that climate ain’t just for the pocket-protector crowd. You have to speak to the masses (if you care about “winning”)

  35. 85
    Al Bundy says:

    Killian (WAIS): . Too much pedantism and it becomes quite difficult for laypersons to penetrate the density of… stuff… and some important %, I assume, may be dissuaded.

    It’s all science to me!

    AB: Absolutely. And Eric obviously agrees with you, too. In fact, I bet when scientists chat the word “proof” is used without caveat, because in science the “nothing is ever technically proven” is implied by definition.

    However, attribution is warranted. This whole stupid distraction is yet another brick in the denialists’ wall.

    Perhaps when somebody whines “nothing is ever proven” one should respond,

    “Apparently I’ve overrated you because only a moron wouldn’t understand that that caveat is implied by the simple fact that it’s a scientific discussion.”

  36. 86
    Al Bundy says:

    Ignorant As Trump: So, everyone should accept CC scientists claims without question? Noone can question CC science?

    AB: So anybody can play in the NFL? Dude, the pros can and do “tackle” each other. Asking, “Can I play, too?” is ignorant.

    Fans pick their favorite team and argue over beers. Smart fans talk to the players to get tips. Dumbasses crow about how they’re a better linebacker than Benardrick McKinney.

  37. 87
    Al Bundy says:

    I nominate zebra as referee of conversations in general. What he’s saying makes sense. Do I have a second?

  38. 88
    Al Bundy says:

    moved from WAIS per Eric’s request


    I agree. One possible team:

    Ray’s “caustic, tough, and fair” makes him a good candidate for the lead.
    jb’s playful creativity (those categories… jb, maybe you should work on the Jeopardy! show).
    Your numeracy (for want of a better word).
    nigel’s open-mindedness (to a flaw).

    I can add my systems design talent but methinks I don’t have a moderator’s disposition. That leaves room for a programmer…

  39. 89
    Al Bundy says:

    One desperately needed function is the ability to edit a comment while it’s awaiting moderation.

    A moderation team should probably have seven members, so each person does the primary intake work one day per week. Add in zebra, Kevin, and, hmm… suggestions?

  40. 90
    William B Jackson says:

    No 62 If it were not for “endless deliberate stupidity” would KIA have anything to post? I am not joking in asking this for some time I thought his posts were meant to be sarcastic!

  41. 91
    Killian says:

    Re #76 Nemesis said …sustainable… without funny money…

    1. Not sustainable.

    2. Controlled and funded by gov’t agency.

    We need better awareness of what “sustainable” is. Aurovill is better thought of as an experiment rather than a finished product.

  42. 92
    zebra says:

    Kevin McKinney,

    “who appointed you…”

    Same person who appointed you to do what you do?

    Anyway, what do you think would be KIA’s answer? I’m pretty sure there will never be one.

    If you start with the premise that CO2 has resulted in a larger energy content for the climate system, then, as I have said multiple times with no contradiction, Dorian would have essentially zero probability of occurring absent that difference in energy.

    So, your response to KIA is not scientifically meaningful, and a poor example for the hypothetical lurker who is here to learn about a scientific approach to the climate issue. Just sayin’.

  43. 93
    Victor says:

    So yes, everyone’s favorite troll has gone and written another book. It is a way I have of driving off the spleen and regulating the circulation. Only this one’s different. How different can be gleaned from these excerpts from the introduction:

    “What makes this book different is the fact that I no longer really care whether or not you believe me. As I see things, it’s already too late to argue one way or another on this topic. It’s not that “the science is settled” – I feel sure it isn’t – it’s that the issue is settled. Climate change is no longer a scientific matter, but a social construct. The debate is over and it’s been won by those most adept at influencing public opinion.

    At this point, therefor, it’s no longer a matter of whether “the science” is right or wrong, but whether humanity can survive the exceedingly dangerous “existential” abyss we are now being forced to confront. I’m not talking about the predicted climate disaster, but the social and psychological trauma induced by the extreme demands that will increasingly be imposed as necessary to avoid it.”

    Preprints are available free of charge to all my fans on this blog. Feel free to request a copy by emailing me at doktorgosh (at)

  44. 94
    Nemesis says:

    @Killian, #91

    ” 1. Not sustainable”

    Sustainable agriculture, sustainable electricity, sustainable water management ect:

    “Auroville Towards a Sustainable Future”

    “2. Controlled and funded by gov’t agency.”

    Not true. Sources please…

    ” Aurovill is better thought of as an experiment rather than a finished product…”

    Right, but it’s an experiment going on for roughly 50 years now and they are doing quite well. They built a real forest out of a waste land, they built a living. Is capitalism a finished product? Not yet, but it will be finished soon I bet. Is evolution a finished product? Evolution within the cosmos will never be a finished product, mankind will never be a finished product, I myself will never be a finished product.

    Anyway, we will have a world without money soon one way or another. The days of capitalism are numbered.

  45. 95
    nigelj says:

    AB @88 says “I can add my systems design talent but methinks I don’t have a moderator’s disposition…”

    Your idea of farming out moderation duties makes some sense, but I dont have a moderators disposition either, and I would probably over delete things. Participants in the discussion are probably going to be too biased to make good moderators. Plus a team of 7 moderators would lead to huge inconsistencies. Did ya consider all that?

  46. 96
    nigelj says:

    Victor @93 complains bitterly about the huge “psychological stress” he contends would be caused by climate change mitigation, yet he doesn’t give any examples. I’m not sure how after all this time Victor still doesn’t seem to understand what the IPCC are saying about mitigation. For example the heavy lifting has to be done by governments and corporates, like renewable electricity generation, and the costs of that can be absorbed by the economy and are not huge, and such technical issues don’t impact on ordinary people.

    All that is expected of ordinary people is they do things like buying an electric car if possible, or just getting the bus, using a little bit less electricity, recycle more, etc so we are talking about moderate lifestyle changes. Nobody is expected to freeze to death, go poor, or wear hair shirts. So this doesn’t generate psychological stress of any significance, so once again we have completely inane statements coming from Victor.

  47. 97
  48. 98
    Victor Grauer says:

    #96 nigelj:

    “All that is expected of ordinary people is they do things like buying an electric car if possible, or just getting the bus, using a little bit less electricity, recycle more, etc so we are talking about moderate lifestyle changes.”

    V: I urge you to check out some of Greta Thunberg’s lectures, where she expresses a very different view, in which “half measures” won’t be nearly enough, and urges all of us to, literally, panic. She’s been getting standing ovations from some of the most influential people in the world.

  49. 99
    Al Bundy says:

    Victor: What makes this book different is the fact that I no longer really care whether or not you believe me.

    AB: Noticing* something that has been bleeding obvious to literally everyone else does NOT make your current deliberate lobotomy “different”.

    *Noticing: for the driving force that moves one’s fingers and mouth to kinda sorta become part of the mollassesque proccessing in the moribund cells in your body located where others have frontal lobes

  50. 100
    Al Bundy says:

    nigelj: . This will probably only convince a small number of denialists,

    AB: Correct ONLY if one includes ZERO in the definition of small numbers.

    Pretending that mathturbation might get a small number of the supermodels off that you’re mathturbating to sure feels good, eh?