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There was no pause

Filed under: — rasmus @ 22 January 2017

I think that the idea of a pause in the global warming has been a red herring ever since it was suggested, and we have commented on this several times here on RC: On how data gaps in some regions (eg. the Arctic) may explain an underestimation of the recent warming. We have also explained how natural oscillations may give the impression of a faux pause. Now, when we know the the global mean temperature for 2016, it’s even more obvious.

Easterling and Wehner (2009) explained that it is not surprising to see some brief periods with an apparent decrease in a temperature record that increases in jumps and spurts, and Foster and Rahmstorf (2012) showed in a later paper how temperature data from the most important observations show consistent global warming trends when known short-term influences such as El Niño Southern oscillation (ENSO), volcanic aerosols and solar variability are accounted for.

A recent paper by Hausfather et al. (2017) adds little new to our understanding, although it confirms that there has not been a recent “hiatus” in the global warming. However, if there are doubts about a physical condition, then further scientific research is our best option for establishing the facts. This is exactly what this recent study did.

The latest findings confirm the results of Karl et al. 2015 from the National Oceanic Atmospheric Administration (NOAA), which Gavin described in a previous post here on RC. The NOAA analysis received unusual attention because of the harassment it drew from the chair of the US House Science Committee and the subpoena demand for emails.

Science is convincing because it builds on independent assessments, which either confirm or disagree with previous findings. A scientific consensus is established when many independent lines of evidence underpin the same conclusions.

It is important to realize that science is about universal truths, which means that you should get a consistent picture in a comprehensive analysis. The idea of a hiatus was indeed inconsistent with other indicators, such as the global sea level which continued to rise unabated (Watson et al, 2015). And there was no reason to think that changes in the cryosphere and precipitation had ceased either.

More than 70% of earth’s area is oceans, and sea surface temperatures (SSTs) carry a large weight in the global mean surface temperature estimates. Karl et al. (2015) reported a cold bias in recent SSTs due to changing observing network. This bias gave the false appearance of a slow-down in the warming of the oceans, and by taking into account artifacts from a change in the observing network, Karl et al found a more pronounced warming in the recent decade. Hausfather et al. (2017) studied these more closely, and their findings confirmed the NOAA analysis.

Rising levels of CO2 may not only result in a global mean surface warming, but it is also possible that it accelerates the turnaround of the hydrological cycle (Benestad, 2016). So even a hypothetical period could take place with a reduced warming rate, but it would be accompanied with an accelerated atmospheric vertical overturning.


  1. D.R. Easterling, and M.F. Wehner, "Is the climate warming or cooling?", Geophysical Research Letters, vol. 36, 2009.
  2. G. Foster, and S. Rahmstorf, "Global temperature evolution 1979–2010", Environmental Research Letters, vol. 6, pp. 044022, 2011.
  3. Z. Hausfather, K. Cowtan, D.C. Clarke, P. Jacobs, M. Richardson, and R. Rohde, "Assessing recent warming using instrumentally homogeneous sea surface temperature records", Science Advances, vol. 3, pp. e1601207, 2017.
  4. T.R. Karl, A. Arguez, B. Huang, J.H. Lawrimore, J.R. McMahon, M.J. Menne, T.C. Peterson, R.S. Vose, and H. Zhang, "Possible artifacts of data biases in the recent global surface warming hiatus", Science, vol. 348, pp. 1469-1472, 2015.
  5. C.S. Watson, N.J. White, J.A. Church, M.A. King, R.J. Burgette, and B. Legresy, "Unabated global mean sea-level rise over the satellite altimeter era", Nature Climate Change, vol. 5, pp. 565-568, 2015.
  6. R.E. Benestad, "A mental picture of the greenhouse effect", Theoretical and Applied Climatology, vol. 128, pp. 679-688, 2016.

156 Responses to “There was no pause”

  1. 1
    Ezequiel says:

    A series like 1, 10, 2, 3, 4, 5, 6, 7, 8, 9 is increasing. 1998 being such an outlier is an artifact of doing yearly averages; if they were done on 6, or 18, or any other number of months, the rankings would come out differently.

    Mandatory XKCD:

  2. 2
    Chris O'Neill says:

    Indeed you could simply argue that until something reaches statistical significance, which the slowdown never did, it doesn’t exist.

  3. 3
    tamino says:

    The lack of a “pause” isn’t the entire story. From the perspective of public perception, of more importance is the misleading and deceptive use of “pause” claims by climate deniers. Of course they still claim there was a “pause” (one such effort is dissected here). We need to hammer them about their ludicrous claims, as publicly and as often as we can. As ridiculous as they are, let’s heap ridicule on them and not relent.

  4. 4
    Michel Vasquez says:

    No comments yet? I’m no climate scientist…not even close…but please let’s read some comments…or is it so “factual” that no discussion is needed…even after the Trump victory…I appreciate, deeply, deeply, the work and effort done on this site…I only understand a minutia of what is being discussed…but I know it involves the future of the entire planet, all sentient beings, all of the globe…many, many thanks to those who run this site and…despite the attacks you’ve endured and will, no doubt now will endure, keep running it. I’m only a neophyte in all this but I appreciare the comments, even if I don’t quite understand them. I know you have the fate of earth as your goal…

  5. 5
    Urs Neu says:

    A point in the discussion about the ‘pause’ that caught my eyes was the large number of possible – and not implausible at first sight – explanations for the reduced trend. Many of them were presented as explaining a large part of the reduced warming. Among others: ENSO, solar activity, (deep) ocean warming, data gaps, etc. If you’d sum up alle the suggested influences, their aggregated effect would have been quite a strong cooling trend. This was not the case, and with global temperature being largely back in the range of the long-term trend and the model projections it should be possible to have a second look on the suggested explanations. Provided that global warming has not strongly accelerated (for whatever reason), most probably not all of these influences had the suggested effect. What we can do now is to compare the change of these factors over the last few years, because these should show a similar development as global temperature. ENSO is certainly an important factor. But it probably does not explain the whole increase. Solar activity is still low, thus it might not explain much. I haven’t seen recent data about ocean warming. Data gaps is a longer term effect that might ‘hide’ some warming, but can’t explain such a strong interannual increase. These are just first thoughts, but it might be interesting to dig and discuss more in depth. It’s not about the long-term trend, but it might give us hints about interannual or decadal variability.

  6. 6
    JCH says:

    The GMST decreased from 2005 through 2012. If the same thing happens again from 2016 through 2023, nothing will be done. All the name calling and scorn and ridicule in world won’t change a thing.

    So, is the pause that never happened going to happen again?

  7. 7
    Rocketeer says:

    So why are we still talking about the 1998-2013 pause when we should be talking about the 2007-2016 hyper-warming? If you look at the major datasets (global surface and satellite), the average trend over the last ten years is +0.325C per decade. The strongest warming is found in the (denier favored) satellite data which averages to about 0.4C per decade. The weakest warming is found in the NOAA database with the those hated Karl corrections (+0.187C, the only dataset showing less than 0.3C). Since their favorite sources now clearly demonstrate the hyper-warming, will the deniers become believers? Now granted the ten year time frame is too short to draw any serious conclusions, but that didn’t stop deniers from declaring the pause at least as early as 2008.

  8. 8
    MikeH says:


    >won’t change a thing.

    Actually that is far from true. The “name calling, scorn and ridicule” of climate science using a non-existent “pause” in planetary warming as a club has had a big impact on public attitudes and has played and continues to play a role in preventing us from mapping out a sensible political response to GHG emissions.

    The same groups and people who regularly ridicule and pour scorn on climate science are already declaring the start of the next “pause”.

  9. 9
    Terry Morse says:

    Further analysis of the “hiatus” in Huber & Knutti : “Natural variability, radiative forcing and climate response in the recent hiatus reconciled”, 2014

  10. 10
    nigelj says:

    There was clearly no pause in the increase in heat energy within the system as a whole, so to speak. However it may be better to treat this term ‘no pause’ as a specific thing just related to energy issues.

    Saying there was no pause at all may be unwise. I think there was a pause in terms of a slight slowdown in surface temperatures visible in the graph above, from about 2002-2012. The general public would see this as a pause or slowdown, and it may be prudent to acknowledge this. Otherwise you could be accused of trying to air brushing away an obvious slowdown after 2002. (This slowdown is now clearly over).

    Of course this particular pause was temporary, predictable and due to a combination of natural factors. My understanding is it is particularly related to how heat energy is dispersed in the oceans and in what layers. There may be more like this, but it’s to be expected. I actually think most people get that and understand that its within an overall rising trend.

    The sceptics are desperately trying to create the impression it was not predicted and means global warming has stopped indefinitely, which it hasn’t however I think the public now mostly increasingly see through this sceptical nonsense. You need to remind the public that the very first IPCC reports stated that there would be slow periods of roughly 10 years and temperatures were never predicted to increase in a precisely straight line.

    I’m not a climate sceptic. We are warming the climate, however it would be unwise of the climate community to over simplify the issues.

  11. 11
    Jon Kirwan says:

    I wanted to highlight this phrase, “consistent picture in a comprehensive analysis,” and add this quote from an article by James Lett that I remember reading nearly three decades ago:

    “If you are willing to be selective in the evidence you consider, you could ‘reasonably’ conclude that the earth is flat.”

    How true.

    Comprehensiveness is no guarantee, since no one has a working crystal ball to tell them what the future may yet bring. But comprehensiveness isn’t an option, either. It’s a must to help mitigate against all too easy self-deception.

    Sadly for most of us, comprehensiveness takes a lot of time and effort and most of us just aren’t free enough to commit that much of our lives to achieving a comprehensive view on this subject (or any, to be honest about it as few of us are allowed the chance to dedicate ourselves so singularly.)

    It’s why I consider myself privileged in part because I happen to live in a time when our societies support the work of scientists and that I’m allowed some leisure time to read what they say. (I have been still more privileged to have worked with scientists as an engineer developing instrumentation used from everything from brain to space research and that I can call and/or write scientists who then take a moment to read and helpfully reply.) I couldn’t have asked to live at a better time and I’m in debt to those scientists who not only struggle to reach a point of productivity, but who then go on to imagine and then perform interesting work, and then generously do still more by setting aside time to write and then publish an accurate reflection of that work effort.

    It boggles my mind that some in society are so quick to set aside this boon. It flummoxes me that some go so much further as to imagine that not just one or two scientists, not just one or two organizations of scientists, but that all scientists and all of their organizations in fields from physics to biology, whether from deep oceans to outer space, are colluding in some kind of ill-intentioned political conspiracy of power and domination. And that they believe this with such facility and such lack of concern about their own credulity.

    What can I say to that?


    I never imagined a pause even when some climate scientists were being circumspect (and even equivocal), in public. It felt like far too much was being built far too quickly on far too little. For me, it wasn’t so much because there had been far too little time and thought allowed for any consensus to develop, though there had been far too little time for that. It wasn’t because I knew so much and could tell. I don’t and I couldn’t tell. But more because it was barely a bump along the road and largely inconsistent with the very much larger body of evidence I already knew about and that a still more comprehensive view must also include.

    Comprehensiveness is so important.


    A long time ago, peripatetic philosophers would focus on charismatic argument without lifting a finger to actually test their ideas beyond the simplest of sensory observation. Even adding in logical consistency alone, isn’t enough to guarantee anything true. (Self-consistent ideas can be terribly and entirely wrong.)

    It was people like Galileo, who to any sane person at the time must have somehow looked insane as he polished and re-polished wood, created vessels of dripping water, and rolled balls down inclined planes for years at a time, who made strides dragging down wandering philosophies and tying them sternly and forcefully down to repeatable, experimental results.

    In part, it was the acceptance of combining our imagination, with logical consistency, with the ability to communicate to others in way that allows rigorous deduction, dealing with informed objections forthrightly, and with requiring support from experimental result (itself, not raw sensory observation but instead observation made through the light of more prosaic theory supported by more prosaic experimental result supported by still more prosaic theory, etc), which has meant a close tethering of our creative imagination to reality and therefore efficient, rapid progress describing the surface textures of a deeper reality (we may never hope to fully apprehend in all its depth.)

    An essence of science then is to keep hypotheses from drifting too far from experimental results. One allows imagination to wander, of course. But one then takes in observational data, tests hypotheses, and then tries to interpret experimental result in the light of such hypotheses. We’re trying to get at the truth and we’d like to know why our universe is how it is. So I do think it’s important, as a within-the-fields endeavor, to investigate informed objections such as, perhaps, a pause. But this is insider business, so to speak. And us lay people need to permit time for scientists to do their business.


    It sure made the news, though. And has had an indelible impact on the public dialog, a price for which we will be paying for some time yet to come.

  12. 12
    Victor says:

    “It has been claimed that the early-2000s global warming slowdown or hiatus, characterized by a reduced rate of global surface warming, has been overstated, lacks sound scientific basis, or is unsupported by observations. The evidence presented here contradicts these claims.”

    “Making sense of the early-2000s warming slowdown”

    John C. Fyfe, Gerald A. Meehl, Matthew H. England, Michael E. Mann, Benjamin D. Santer, Gregory M. Flato, Ed Hawkins, Nathan P. Gillett, Shang-Ping Xie, Yu Kosaka & Neil C. Swart

  13. 13
    Craig says:

    I’ve been watching global warming for several decades. It’s a reality and I accept it.

    But we know there are variations from time to time. We know sometimes what’s causing the variations. And sometimes there are variations and the reasons are not fully understood. On a minor note, we also know that when high temperature records are broken, it seems to have a higher probability of happening in El Nino years.

    With some of these issues in mind, perhaps the early 2000s should be described as a time when the warming continued but the rate of warming eased off. The proper question then would be: what happened? Was it the drop in solar radiation? Was it the increasingly huge amount of pollution from coal in countries like China and India that can cause local cooling (and maybe not so local given the huge amounts)? Was it a statistical variation?

    Conversely, could the sudden sharp rise in temperatures in 2015 and 2016 be a function to some degree of China substantially reducing coal burning (it also reduced the illegal burning of coal in incinerators)? Incidentally, it would be helpful if more people looked at U.S. coal consumption since 1900; coal is now in its third collapse. How have those collapses affected temperatures?

    The long-term warming trends are clear. But it’s crucial to understand better the variations and not undersell them.

  14. 14
    Chris O'Neill says:

    JCH #6

    The GMST decreased from 2005 through 2012. If the same thing happens again from 2016 through 2023

    I wonder what happened to the period from 2012 to 2016?

  15. 15
    JCH says:

    The pause was predicted here at RC: Warming, interrupted: Much ado about natural variability

    And, we have this response, which I keep handy, in the comment section of that thread:

    …please note that this is Kyle’s article not mine, though I did encourage him to write it for us. I think the interesting question raised (though not definitively answered) by this line of work is the extent to which some of the pause in warming mid-century might have been more due to decadal ocean variability rather than aerosols than is commonly thought. If that is the case, then a pause or temporary reduction in warming rate could recur even if aerosols are unchanged. Learning how to detect and interpret such things is important, lest a temporary pause be confused with evidence for low climate sensitivity. –raypierre]

    And like clockwork, out popped the stadium wave and lots of claims of low climate sensitivity.

    Screaming at the pause does no good. It has to be understood.

    Just my opinion, but a possible lesson of the pause is that climate sensitivity may be a bit higher than many think, and that we are in the early stages of an accelerated warming period… and I don’t think anybody can say how long it might last. It could be over now; it could last another decade.

    Scientists need to figure out when the pause started. IMO, it started long before 1998. Its origins are Eastern Pacific cooling, which may date back to the mid to late 1980s. I suspect it masked AGW in a pretty significant way.

  16. 16

    n 10: Saying there was no pause at all may be unwise. I think there was a pause in terms of a slight slowdown in surface temperatures visible in the graph above, from about 2002-2012.

    BPL: You may think so, but statistical analysis shows otherwise. That’s the fact, Jack.

  17. 17
    tamino says:

    Nigelj says (#10) that “it would be unwise of the climate community to over simplify the issues,” after speaking of “this particular pause” as being “temporary.”

    By accepting the “pause” without giving any evidence of it or specifying exactly what “pause” means, he’s over-simplifying in exactly the way he warns us against.

    Because the elephants in the room is twofold: 1) what is the precise definition of “pause”? 2) Where’s your solid evidence?

    The only way you can claim there was one, is if you call any lack of temperature increase a “pause,” no matter how brief. If you want to do that, I can use the daily global average temperature data from Berkeley Earth and point you to hundreds of “pauses” in the last decade. And I can point to just as many accelerations, including the massive one we’ve just seen leading up to the record-breaking 2016.

    All this “pause” talk is garbage. You can only claim a pause if you abandon any requirement for precise definition and rigorous proof. Unfortunately too many legitimate scientists have fallen into that trap, with the paper from Fyfe et al. the most prominent.

    If you don’t care about genuine evidence, there were as many pauses (and restarts) as you want. If you do care about genuine evidence, then when it comes to the “pause” idea either put up or shut up.

  18. 18
    Piotr says:

    Re: Victor (12)

    If you fail (Unforced variations, April 2016) – try, try again (Unforced variations, May 2016; current thread) ?

    And that hiatus you speak of – could you point to it in, say: ?

  19. 19

    #12, Victor–Yes, most of us know about Fyfe et al. After all, you’ve brought it up several times.

    It’s important to distinguish between two ideas, though. One is that the rate of surface warming was lower during the ‘pause’, which AFAIK is not controversial, and the other is that that had some bearing on the actual warming trend changing. It seems pretty clear that from a statistical POV there is no reason to think that the ‘pause’ was anything but variability.

    Failing to distinguish clearly between these two ideas has led to a great deal of confusion, in that folks get into contention about the existence or otherwise of the pause without noticing that they aren’t talking about the same thing.

  20. 20
    jgnfld says:

    My problem with Fyfe et. al. is that they assume the slowdown as real too much (specifically referring to “the slowdown” on 20 occasions) and assume the possibility of internal variability alone as a sufficient explanation too little.

    There is also this sentence which occurs immediately after mentioning there is no statistical reason to argue for a slowdown: “Our goal here is to move beyond purely statistical aspects of the slowdown, and to focus instead on improving process understanding and assessing whether the observed trends are consistent with our expectations based on climate models.”

    While it may well be possible to explain fluctuations further with present data inputs and techniques, simply assuming that there is further explanatory power to be had with them is something I am uncomfortable with. But then my background is in statistics.

  21. 21
  22. 22
    Jim Eager says:

    Craig wrote @13: “perhaps the early 2000s should be described as a time when the warming continued but the rate of warming eased off.

    No, that is inaccurate. The rate of warming (the underlying trend, or the man walking on the beach, if you will) continued unabated, as the increase in ocean heat content and recent el Nino on steroids clearly demonstrates. It is the rate of increase in the average surface temperature that eased off for a time. The “pause” was a temporary excursion caused by natural variability (the dog the man is walking), one of several in the temperature record (the escalator). There is no evidence what so ever that there was any change in the underlying trend.

    I agree with you that it is important to understand the drivers of short term variations in surface temperature, whether they be natural or anthropogenic, but it is equally important not to undersell the unabated continuation of the underlying trend.

  23. 23
    Vendicar Decarian says:

    The only argument needed to ignore the claimed “pause” results from it’s statistical insignificance.

    It is obviously still good that the data corrections are made of course.

  24. 24
    Titus says:

    @1Ezequiel says: “A series like 1, 10, 2, 3, 4, 5, 6, 7, 8, 9 is increasing”

    You forgot the (-) negatives values around the years 2000, 2008, 2011. And where we end up after 2016 is anybody’s guess right now. So your example is at least a tiny bit misleading.

    Is this ‘alternative data’. Love the phrase.

  25. 25
    Tom Zupancic says:

    How does Trump’s gag order affect the ability of scientists to communicate?

  26. 26
    nabilswedan says:

    Period of pause are inherent to changes in the the climate. These changes have increased surface temperature by about one degree Kelvin in 250 years. It is infinitesimal on annual basis compared with surface temperature of 288 degrees Kelvin. Processes of this nature are known to physics, engineering, or even mathematics to occur at levels. Take a close look at sea level rise as recorded by the University of Colorado. It rises at campaigns, each having about linear trend. Stratospheric temperature decreases at levels, Thompson et al. (2012), Nature 49, 29: 692-697. The same is true for surface temperature. However, It is harder to see because of surface variability. After this El-Nino perturbation, expect surface temperature to rise and a pause to follow. This is the nature of climate change.

  27. 27
    dyqik says:

    re: 25. It means that websites like this can now be headlined with “The truth about climate change that the government doesn’t want you to find out about!!!11!”.

    Maybe that’s even useful at targeting certain parts of the population. ;)

  28. 28
    Chris O'Neill says:


    You forgot the (-) negatives values around the years 2000, 2008, 2011.

    I wasn’t aware that the global temperature anomalies of those years (on any of the usual baselines) were negative.

    Let’s all thank Titus for informing us yet again.

  29. 29
    Vendicar Decarian says:

    Big plans for EPA

    Super Swan got his hands on the Trump team’s “Agency Action” plan for the EPA. It’s a tightly-held document that fleshes out Trump’s campaign promises to gut the agency. It’s the handiwork of Myron Ebell, director of the Competitive Enterprise Institute’s Center for Energy and Environment. Trump appointed Ebell, a prominent opponent of climate change activists, to lead the EPA transition.

    Our takeaway: Environmental Protection Agency is set for an absolute hammering under Trump.

    The deets:

    —”Potential opportunities for budget reductions”: A category that includes $513 million in cuts to the “states and tribal assistance grants” … $193 million in savings from terminating climate programs … $109 million in savings from “environment programs and management.”

    Listed as initiatives to stop: “Clean Air Act greenhouse gas regulations for new (NSPS) and existing (ESPS or the ‘Clean Power’ Plan) coal and natural gas power plants … [CAFE] Standards … Clean Water Section 404: Waters of the U.S. Rule (wetlands) … TMDL (Total Maximum Daily Load) for Chesapeake Bay.
    “Key opportunities”: “Issue an executive order barring EPA from overruling federal/state regulatory/permit decisions unless in clear violation of established law.”
    Changing the way the EPA uses science: “Unless major reforms of the agency’s use of science and economics are achieved, EPA will be able to return to its bad old ways as soon as an establishment administration takes office.”

  30. 30
    Claude says:

    A new group on climate change has just been formed. Its name ” Climate Change ” Do not hesitate to register. Welcome everyone.

  31. 31
    nigelj says:

    Barton Paul Levinson @16

    “n 10: Saying there was no pause at all may be unwise. I think there was a pause in terms of a slight slowdown in surface temperatures visible in the graph above, from about 2002-2012.”

    “BPL: You may think so, but statistical analysis shows otherwise. That’s the fact, Jack.”

    Fair enough Barton, I agree in a science / maths sense. But you miss the point I’m making. The general public will see it as a pause or slowdown (and will also not differentiate between these two terms). Telling them there was no pause will come across like saying black is white. You have to see it from the public’s perception and use of language. Climate sceptics will have a field day as well.

    I would think it better to say “there was a pause or slowdown (or whatever) in surface temperatures for reasons a, b, and c but no pause in the increasing greenhouse effect. Most people would also understand the science of that.

  32. 32
    nigelj says:

    Tamino @17, thanks. I guess I would be inclined to say any lack of temperature increase in is indeed a pause or slowdown and regardless of the time frame. I’m looking at this a bit more from public perception and use of words etc than a science based definition. I think you have to do that.The public will see the period 2002-2012 as a pause or slowdown – and will also use these words to mean the same thing.

    For want of a better word the public are applying commonsense and we can’t blame them. Telling them there was no pause or slowdown may be scientifically true at some level but unwise from a communications point of view.

    From a science point of view you could say a true pause in temperatures only happens at some particular level. But this would be hard to define wouldn’t it?

    The Ipcc in their early reports appeared to say a slowdown or pause of 10 years is likely occasionally, and is just natural variation. The implication being that a seriously longer pause than 10 years could indicate something unpredicted and concerning is going on or the basic greenhouse theory was flawed. Perhaps this is the best definition of a real, concerning genuine pause.

    Of course it hasn’t happened. We have in fact seen a pause or slowdown of about 10 years from 2002 – 2012. This is in fact pretty much exactly in line with what climate model predictions made back in the early 1990s! Rather than downplay the idea of a pause, I would emphasise this fact that the climate models have been vindicated.

    However I’m not a climate scientist, just an interested but educated casual observer of climate change, and see this from this point of reference. You have vastly more expertise than me and I hugely respect your opinions and published science.

  33. 33
    krisbalmain says:

    So the Hiatus is false, yet the article continues to bring up peer reviewed literature explaining how it might have occurred?

    I’m confused sorry.. the hiatus was based on the temperature records.

    Whats more, have those arctic record discrepancies been applied right back to 1880?? if they’re not, how can you even begin to compare modern temps to temps from back then?

  34. 34
    Mr. Know It All 2 says:

    The earth is fairly large. :)

    I doubt there are enough sensors available to get a really accurate global temperature. What is the probable +/- tolerance of claimed global temperatures?

    One thing I was wondering about: Do the models take into account the heat released from using energy to run our cars, trucks, ships, trains, planes, tractors, etc; heat & cool buildings; manufacture stuff, etc????? Not the CO2 effect, but the added man-made heat. I suspect these are included in the models, but just wanted to verify.


  35. 35
    Mr. Know It All 2 says:

    What is the current best estimate of the incoming versus outgoing planetary energy imbalance? I think I read it’s about 0.6 W/m^2.

    How much of that goes to the atmosphere; and how much to various altitudes in the atmosphere?
    How much to the ocean; and how much to various ocean depths?
    How much to land?
    How much to melting ice?

    Is the 0.6 W/m^2 (or whatever the latest is) measurable via satellites? Or only a calculated value?

  36. 36

    Rasmus: “On how data gaps in some regions (eg. the Arctic) may explain an underestimation of the recent warming“.

    The Arctic has certainly warmed a lot over the past twenty years (1996-2016). I’m curious how the warming is reliably attributed differently (so it seems) than the Arctic warming of, say, 1916-1936?

    There are no doubt regions of the Earth where the climate is known to be stable and other regions where the climate is known to be far more noisy. It seems counter intuitive that the noisiest regions are used to search for the global warming signal. Why not rather avoid these regions, like one would likely avoid noisy environments in trying to detect faint or low frequency signals in general?

  37. 37
    Jim Eager says:

    For Mr Know it all,

    1- Your doubts not withstanding, except for the poles and some remote parts of the ocean, the temperature sensor network is *over* sampled for the purpose of calculating a global mean surface temperature.

    2- The waste heat released by humans using energy has in fact been calculated, and it is minuscule, aproximately two orders of magnitude* smaller than the imbalance caused by the change in the greenhouse effect due to rising CO2. (*Around 0.028 w/m^2 vs 2.9 w/m^2)

  38. 38
    Mr. Know It All 2 says:

    25 – Tom

    They can still communicate with each other, right? Should be no problems there. They just cannot spew politically correct propaganda like they used to, right?

    I’d like to know what the carbon footprint is of all the Trump-hating protests, marches, riots, police enforcement, burning stuff, yelling, screaming, making signs and obscene costumes, flying all over the planet to protest on Soros’ dime, etc, etc, etc.

  39. 39
  40. 40
    Hank Roberts says:

    Waste heat vs greenhouse warming – Skeptical Science
    Jul 27, 2010 – How much does waste heat contribute to global warming? … is currently adding about 100 times more heat to our climate than waste heat. …… from combustion of fossil fuels WERE causing global warming the sustainable …

    Greenhouse warming 100 times greater than waste heat
    Jul 27, 2010 – How much does waste heat contribute to global warming? …. Internal combustion engines for instance are very efficient in the way they employ …

  41. 41
    Vendicar Decarian says:

    27: “Do the models take into account the heat released from using energy to run our cars, trucks, ships, trains, planes, tractors, etc; heat & cool buildings; manufacture stuff, etc?????”

    I take it that you are incapable of adding and subtracting and can’t figure out how to compare the energy released by man to the energy delivered to the earth’s surface from the sun and radioactive decay from below?

    If you can add and subtract then you can figure it out for yourself in a couple of minutes.

    If you can’t add and subtract, then what makes you think that you will understand the answer?

    How many watts of solar energy reach the earth’s surface per day?

    How much energy is used by man?


    Get back to us with your result.

  42. 42
    Phil Scadden says:

    Mr Know it All, the standard paper on measuring surface temperature and quantifying uncertainty would be Hansen and Lebedeff [1987] but see also this paper and this for HadCrut.

    See here for discussion of contribution of waste heat. It contributes 0.0028W/m2 compared to human greenhouse gases contribution of 2.9W/m2. At 1/1000 the level off GHG contributions, I think it can be safely ignored.

  43. 43
    Spencer Hill says:

    Thanks for the post. Hoping you can clarify your statement about overturning, which is tripping me up: “Rising levels of CO2 may not only result in a global mean surface warming, but it is also possible that it accelerates the turnaround of the hydrological cycle (Benestad, 2016).”

    One of the single most robust responses in models (from RCE to GCMs) to warming is a reduction in the global mean overturning strength, and this is interpreted (e.g. most famously in Held and Soden 2006) through a very simple physical picture: globally averaged, precipitation (P) balances the flux of moisture out of the boundary layer, the latter being the product of the upward mass flux (M) and the specific humidity (q), i.e. P~M*q. Clausius clapeyron causes specific humidity to increase at roughly 7% per degree Celsius warming, and separate energetic constraints cause precipitation to increase at roughly 2% per degree C. As a result, the mass flux must weaken by roughly 5% per degree C.

    (In full disclosure, I haven’t read the Benestad paper you cite. In skimming it I couldn’t find an obvious physical explanation for this claim.)



  44. 44
    Mr. Know It All 2 says:

    Thanks for your answers on waste heat. The answer was ~1% of greenhouse gases – about 0.028 w/m^2.

    BUT what is the total NET planetary energy gain? I think it’s ~ 0.6 w/m^2.

    Do we know how the net gain is distributed around the planet:
    How much of the 0.6 w/m^2 goes to the atmosphere? (do some layers get more warming than others?)
    How much to the ocean? (ditto)
    to land?
    to ice melting?
    to water evaporation?

  45. 45
    Hervé Douville says:

    Thanks for the post. Could we however distinguish the communication from the science about climate change and not throw the baby out with the bathwater? On the one hand, there was no statistically significant pause in global warming and working on such an hypothesis might be considered as putting too much emphasis on the rhetoric of the global warming sceptics. On the other hand, the scientific debate was NOT a red herring since it was not only about quantifying the potential modulation of global warming by internal climate variability, but also about understanding the underlying mechanisms. It gave us the opportunity to recognize once more that our global climate models are quite uncertain in this respect, which does not mean that their long-term projected global warming is wrong (albeit also uncertain in its magnitude and patterns). It was also somewhat illuminating about the haste with which we – scientists – trust our models once they capture an observed trend (even if partly contradicted by later data corrections) and about a publication bias toward successes (rather than failures) in capturing the observed climate variability using imperfect models… Something we might want to think about without casting doubt about the reality, the reason and the pace of global warming.

  46. 46

    Unlike El Niño and La Niña, which may occur every 3 to 7 years and last from 6 to 18 months, the PDO can remain in the same phase for 20 to 30 years. The shift in the PDO can have significant implications for global climate, affecting Pacific and Atlantic hurricane activity, droughts and flooding around the Pacific basin, the productivity of marine ecosystems, and global land temperature patterns. This multi-year Pacific Decadal Oscillation ‘cool’ trend can intensify La Niña or diminish El Niño impacts around the Pacific basin,” said Bill Patzert, an oceanographer and climatologist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “The persistence of this large-scale pattern [in 2008] tells us there is much more than an isolated La Niña occurring in the Pacific Ocean.”

    Natural, large-scale climate patterns like the PDO and El Niño-La Niña are superimposed on global warming caused by increasing concentrations of greenhouse gases and landscape changes like deforestation. According to Josh Willis, JPL oceanographer and climate scientist, “These natural climate phenomena can sometimes hide global warming caused by human activities. Or they can have the opposite effect of accentuating it.”

    It is really evident that there is a decadal cooling influence and that this may indeed evolve into a millennial cooling.

    On climate I am inclined to think that most 20th century warming was quite natural. With a dimming sun and resurgent La Niña activity suggesting a cooling influence this century. It means that anthropogenic greenhouse gases may be less influential than believed – but at any rate restoring agricultural soils and ecosystems can mop up vastly more carbon over decades. By then there will be 21st century energy. So it’s a non-problem – at worst a massive distraction from far more serious development and environmental problems. And the best we can do anyway is globally restore soils and ecosystems. While commercialising 21st century energy sources and reaping trade and productivity windfalls in growing economies.

  47. 47
    Ray Ladbury says:

    Misterknowitall: “… flying all over the planet to protest on Soros’ dime, etc, etc, etc.”

    And we’re done. Sorry, Mr. Know Nothing, but life is too short to waste my time engaging with imbeciles who believe every lie they read on the alt-right press. Long experience has shown me that when such types show up here, the exchange winds up being all about them. Maybe come back when you can see beyond your own ego. B’bye.

  48. 48

    KIA 34: I doubt there are enough sensors available to get a really accurate global temperature.

    BPL: Take a course in statistics and learn about “sampling.”

  49. 49
    Jim Eager says:

    Where’s Mr. Know It All now that his questions have been answered and he’s been shown to know practically nothing?


  50. 50

    Concerning pauses, IMO it’s all said with the well known “global warming escalator” plot , which i somehow did not find anymore on

    Now for gods sake let’s focus on what to do! It has to be communicated, that what is done isn’t even nearly enough, that
    – consume much less,
    – produce much more efficiently,
    – use much more renewables
    has to be promoted deeply and largely.