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Two graphs show the path to 1.5 degrees

Filed under: — stefan @ 21 April 2021

In the Paris Agreement, just about all of the world’s nations pledged to “pursue efforts to limit the temperature increase to 1.5 degrees Celsius above pre-industrial levels”. On Saturday, the top climate diplomats from the U.S. and China, John Kerry and Xie Zhenhua, reiterated in a joint statement that they want to step up their climate mitigation efforts to keep that goal “within reach”.

But is that still possible? Here are two graphs.

Global temperature trend (relative to mean 1880-1910, NASA data). The colored curve shows the moving average over 12 months, the black line the linear trend over the last 50 years. Transient warmth following two strong El Niño events in the tropical Pacific is indicated by arrows. If everything continued like this, the 1.5 degree limit would be exceeded around 2040.

The first graph shows the global temperature trend. Warming has progressed essentially linearly for fifty years in response to increasing CO2 emissions. Although the latter accelerate the rise of CO2 in the atmosphere, on the other hand, radiative forcing (which causes warming) increases only with the logarithm of CO2 concentration, and therefore roughly linearly since the 1970s. Any acceleration of warming over the last decade is not a significant trend change. It is linked to two El Niño events in recent years, but that is part of natural variability. Does anyone remember the discussion about the supposed “warming pause” in the early 2000s? It also never was statistically significant, nor did it signify a trend change.

Therefore, if emissions continue to grow, we expect a further roughly linear increase in temperature, which would then exceed 1.5 degrees around 2040. If we lower emissions, the trend will flatten out and become roughly horizontal as we reach zero emissions. Therefore, these observational data do not argue against the possibility to still keep warming below 1.5°C.

Exemplary emission trajectories with CO2 emission budgets that, according to the IPCC, correspond to limiting warming to 1.5 °C with 50% probability (solid) or limiting it to 1.75 °C with 67% probability. The same emissions as in 2019 were assumed as the starting point in 2021, assuming the “corona spike” in 2020 is likely to be temporary.

The second graph shows global CO2 emission trajectories with which we can still limit warming to 1.5 °C, at least with 50:50 probability. This means: given the uncertainties, this could also land us at 1.6 degrees, but with a bit of luck, it could land us a bit below 1.5 degrees. The core conclusions:

  •     It is not yet impossible to keep warming below 1.5 °C.
  •     This requires roughly a halving of global CO2 emissions by 2030 (as already stated in the IPCC 1.5 degree report).
  •     If the world dithers for another ten years before emissions fall, it will no longer be possible (red curve).

It should be noted that I have not assumed net-negative emissions here. Many scenarios assume that we first emit too much and that our children then have to pull CO2 out of the atmosphere after mid-century – I think this is not very realistic and also ethically questionable. I think we will probably not be able to achieve more than reducing global emissions to net zero. Even that would require CO2 sinks to compensate for unavoidable residual emissions, e.g. from agriculture.

Conclusion: The limitation to 1.5 degrees is still possible and from my point of view also urgently advised to avert catastrophic risks, but it requires immediate decisive measures. I am curious to see what the climate summit scheduled by US President Joe Biden will bring in the coming days!

Link

Fact check by Climate Analytics to the claim that we can no longer limit warming to 1.5°C.

This article originally appeared in German at KlimaLounge.

166 Responses to “Two graphs show the path to 1.5 degrees”

  1. 101
    CCHolley says:

    RE. Victor @100

    And sorry, but the impression we get from the graph displayed there is not at all like the one offered by Stefan. Even after the adjustments, the contrast between the steep rise from the late 70’s to the late 90’s and the levelling after the El Nino of 1998 remains apparent, while Stefan’s version obscures it.

    They are exactly the same, both show the NASA GISS data sets and are identified as such. It is also quite clear when you look at them side by side that they are the same, except Stefan’s starts at 1970 and ends at 2020. And it is NOT *Stefan’s version*, it is NASA’s version. Victor is seeing things–things that he apparently wants to see. He can continue to claim they are different all he wants until hell freezes over (which BTW is not going to happen) but they absolutely positively are the exact same representations of the exact same data. PERIOD.

  2. 102
    Victor says:

    99 nigelj says:

    Victor: “Lack of basic reading skills abounds on this blog. It was not my decision to discount the two El Ninos beginning in 2016, but Stefan’s. Go back and read his second paragraph.”

    nj: I can see how you would think that, but Stefan didn’t do that. He did not say the el ninos in 2016 and 2019 can be ignored when calculating a climate trend over for example the period 1998 – 2020. No scientist would ever just leave out data that is available. If you have data you use it. He only said that the two el ninos do not constitute an ACCELERATION of warming (defined as a fundamental change from the trend over the last 20 years, or longer ).

    V: Sorry but I have no idea what you mean by the word “acceleration” in the present context. Where is the “acceleration” in question if not in the data already represented in Stefan’s graph? Seems clear to me that Stefan is referring to the increased levels of temperature reflected in the data from 2016 on, which do indeed represent an acceleration. And as also seems clear, Stefan is (wisely) cautious about including this data as part of a trend since El Ninos are produced, not by “climate change,” but “natural variation.” And yes, it looks like he did nevertheless include those years in the trend he displayed. I have no idea why he would do that, but as far as I can see it has nothing to do with “acceleration.”

    nj: The slow period of warming around 2002 – 2010 is over. Finished.

    V: Well first of all, the “hiatus” is usually understood to span the years 1998-2015. As far as it being “finished,” sorry but I’ve heard that same dismissal uttered over and over again for many years now, on the basis of a long string of mistaken and mutually contradictory “explanations” now long forgotten.

  3. 103
    jgnfld says:

    Re. “until hell freezes over (which BTW is not going to happen)”

    So…the 2nd law doesn’t apply in hell??!!

  4. 104

    #103, jgnfld–

    Well, you’re asking us to wade in deep waters, but if the paraphrase of the 2nd law of thermodynamics “You can’t break even” is correct, then I would say that yes, it applies in Hell.

  5. 105
    John Pollack says:

    jgnfld @102 Hell, no.

  6. 106
    nigelj says:

    Victor @102, the ‘spikes’ or peaks in warming of 2016 and 2019 are not evidence of an acceleration in the context of the climate issue. They are just spikes in warming driven in part by very short term natural variability. An acceleration in climate terms means a change that is more than just two or three years, and which includes more than just el nino years, and that is the result of a change in a forcing like AGW. You probably need 10 years of data. This is what Stefan meant by them NOT being evidence of an acceleration. This is why I said: acceleration as defined as a “fundamental” change from the trend over the last 20 years, or longer.

  7. 107
    Victor says:

    101 CCHolley says:

    Victor @100: “And sorry, but the impression we get from the graph displayed there is not at all like the one offered by Stefan. Even after the adjustments, the contrast between the steep rise from the late 70’s to the late 90’s and the levelling after the El Nino of 1998 remains apparent, while Stefan’s version obscures it.”

    CC: They are exactly the same, both show the NASA GISS data sets and are identified as such. It is also quite clear when you look at them side by side that they are the same, except Stefan’s starts at 1970 and ends at 2020. And it is NOT *Stefan’s version*, it is NASA’s version. Victor is seeing things–things that he apparently wants to see. He can continue to claim they are different all he wants until hell freezes over (which BTW is not going to happen) but they absolutely positively are the exact same representations of the exact same data. PERIOD.

    V: They are not the same. The two graphs may be based on the same data, but the manner in which they are presented is different. Stefan’s version ( https://www.realclimate.org/images/1.5-degree-limit-ENSO.png ) creates the impression of a continuous linear progression over the last 50 years, while one can discern in the version you’ve offered ( https://climate.nasa.gov/system/internal_resources/details/original/1987_yearly_temperature_anomalies_from_1880_to_2019.jpeg ) a clear contrast between the ranges of 1979 to 1998 and the very different period 1998 to 2015. Much of the difference is obscured by the trend line appearing in Stefan’s version which fools the eye into seeing a simple continuity, obscuring the difference that’s so apparent when the trend line is removed.

    The real situation becomes clear when we run the numbers: According to your graph, a gap of .8 celsius separates 1979 from 1998, while a gap of only .2 degrees separates 1998 from 2015. The difference is clearly apparent when we are not distracted by the (misleading) trend line. It is all too easy, by the way, to display a line between any two points one may choose, in order to produce the illusion of a meaningful trend. I’ve seen this “trick” many times in the cli. sci. literature and it never ceases to amuse/disturb me.

  8. 108
    Victor says:

    96 CCHolley says:

    RE. Victor @95: “Moreover, there are other [graphs] which offer a radically different picture, such as UAH6, in which the peak at 2010 is far below that of 1998, or RSS or, as already noted, Hadcrut4; or even the Wood for Trees index”

    CC: These are NOT apples to apple comparisons. The satellite records are for the lower troposphere, and are NOT surface temperatures, which is what the discussion is about. The others show RAW data that has not been corrected for coverage biases.

    V: So what are you implying? The satellite records are to be ignored? Only surface temperatures are “what the discussion is about”? Really? I thought the discussion was about the effect of CO2 levels on temperature trends — as evaluated from BOTH surface and troposphere data.

    As for those “coverage biases,” any correction of the surface data should bring the corrected data into line with the satellite data, which is, moreover, not subject to all the many discrepancies the “corrections” were designed to reconcile. Yet, examining the most recent version (six) of the UAH data, we see a radically different picture: (https://www.woodfortrees.org/plot/uah6/from:1970/to:2020/mean:12 ) Why?

    There has been, in fact, considerable controversy surrounding the “corrections” both you and Stefan take for granted. For one thing, any alteration of long established data is a very serious matter that should be undertaken only with the most rigorous controls and by totally unbiased researchers. Yet, as we both know, Thomas Karl is very far from being impartial, having towed the standard “climate change” line for many years. The project reported in the Karl et al paper of 2015 involved careful consideration of a great many data sources of varying scope and reliability and a great many decisions had to be made as to what to include, what to adjust and what to eliminate. While I wouldn’t want to accuse Karl or any of his associates of deliberate fraud, unconscious confirmation bias is a well-known pitfall for any scientific research. Which is why any such effort should be supervised by individuals with no vested interest in the outcome.

    From the essay, “Climate scientists versus climate data,” by John Bates (https://judithcurry.com/2017/02/04/climate-scientists-versus-climate-data/ )

    “A NOAA NCEI supervisor remarked how it was eye-opening to watch Karl work the co-authors, mostly subtly but sometimes not, pushing choices to emphasize warming. Gradually, in the months after K15 came out, the evidence kept mounting that Tom Karl constantly had his ‘thumb on the scale’—in the documentation, scientific choices, and release of datasets—in an effort to discredit the notion of a global warming hiatus”

  9. 109
    jgnfld says:

    Re. kia and “So what are you implying? The satellite records are to be ignored?

    Nope. What is implied is that the satellite record shows the temps in a region where people mostly cannot live and where theory and observation both say that warming is NOT concentrated. It also shows even more cooling at higher elevations, just as the models predict.

    The satellite record is fine for what it is and it corroborates warming just fine.

    What it isn’t, however is what YOU keep “implying” it is. It is neither more accurate of surface conditions than direct surface measurements, nor more reliable than surface measurements (less so, actually for a number of reasons), nor the best indicator of conditions at the surface as it simply does not measure temps at he surface.

  10. 110

    Victor, #108__

    While I wouldn’t want to accuse Karl or any of his associates of deliberate fraud, unconscious confirmation bias is a well-known pitfall for any scientific research.

    Wow. Have a look in the mirror; it isn’t Thomas Karl in there.

  11. 111

    V 107: It is all too easy, by the way, to display a line between any two points one may choose, in order to produce the illusion of a meaningful trend.

    BPL: Even after having it repeatedly explained to you, you still have no Earthly idea what a “trend” is or how it’s produced. Trend lines are not arbitrary. But it’s useless explaining the procedure to you, because I’ve done so before and you never, ever listen.

  12. 112
    CCHolley says:

    RE. Victor @107

    V: They are not the same. The two graphs may be based on the same data, but the manner in which they are presented is different. Stefan’s version creates the impression of a continuous linear progression over the last 50 years, while one can discern in the version you’ve offered a clear contrast between the ranges of 1979 to 1998 and the very different period 1998 to 2015. Much of the difference is obscured by the trend line appearing in Stefan’s version which fools the eye into seeing a simple continuity, obscuring the difference that’s so apparent when the trend line is removed.

    Hell hasn’t frozen over and they are still EXACTLY the same. Victor is just a stubborn arrogant ass. The trend line is THE TREND LINE which was done by doing a linear regression. It is a statistically valid trend line which is meant to show the trend for the period…the period for which temperatures started to rise to the present. It doesn’t fool the eye because it is actually THE TREND.

    The real situation becomes clear when we run the numbers: According to your graph, a gap of .8 celsius separates 1979 from 1998, while a gap of only .2 degrees separates 1998 from 2015. The difference is clearly apparent when we are not distracted by the (misleading) trend line. It is all too easy, by the way, to display a line between any two points one may choose, in order to produce the illusion of a meaningful trend. I’ve seen this “trick” many times in the cli. sci. literature and it never ceases to amuse/disturb me.

    Here is the NASS GISS data without the other temperature data sets for which Stephan’s graph is based and is identical to:

    https://data.giss.nasa.gov/gistemp/graphs_v4/graph_data/Global_Mean_Estimates_based_on_Land_and_Ocean_Data/graph.pdf

    Note from the NASS GISS data the anomaly for 1979 was 0.16 C, for 1998 it was 0.16 C, and for 2015 it was 0.29 C. For the period 1979 to 1998 that’s a 0.45 C difference and NOT 0.8 C and for 1998 to 2015 that’s 0.29 C and NOT *only* 0.2 C. So again, Victor is seeing things.
    The trend line, the one made by doing a linear regression—accepted practice—is only misleading because Victor doesn’t like it. If one is trying to show the temperature trend for the period of which temperatures are rising, you would use the whole period because temperatures are subject to natural variation and the more data, the more accurate the result of the trend analysis. Why wouldn’t you? Especially when you are trying to project the future, which is EXACTLY what Stephan is trying to do. Yet Victor claims: “It is all too easy, by the way, to display a line between any two points one may choose, in order to produce the illusion of a meaningful trend.” While Stephan properly used all the data for the total period of rise to project the future, Victor wants to cherry pick shorter periods, “it is all too easy”, to show something else—something that is not relevant to time series trend analysis and the future. Victor doesn’t even have a clue what it means to do a time series trend analysis.

    Victor is disturbed.

    This has been rehashed so many times on this site and even by Tamino it has became such a bore.

    https://tamino.wordpress.com/2018/06/30/weak-sauce-from-climate-deniers/

  13. 113
    CCHolley says:

    Typo: Note from the NASS GISS data the anomaly for 1979 was 0.16 C, for 1998 it was 0.16 C, and for 2015 it was 0.29 C.

    Should have been: Note from the NASS GISS data the anomaly for 1979 was 0.16 C, for 1998 it was 0.61 C, and for 2015 it was 0.9 C.

  14. 114
    CCHolley says:

    So what are you implying? The satellite records are to be ignored? Only surface temperatures are “what the discussion is about”? Really? I thought the discussion was about the effect of CO2 levels on temperature trends — as evaluated from BOTH surface and troposphere data.

    The title of the article:
    Two graphs show the path to 1.5 degrees

    Introduction:
    In the Paris Agreement, just about all of the world’s nations pledged to “pursue efforts to limit the temperature increase to 1.5 degrees Celsius above pre-industrial levels”. On Saturday, the top climate diplomats from the U.S. and China, John Kerry and Xie Zhenhua, reiterated in a joint statement that they want to step up their climate mitigation efforts to keep that goal “within reach”.

    But is that still possible? Here are two graphs.

    So what is this discussion about?–limiting temperature rise to 1.5 C. What temperature?–dah, global surface temperatures. What are the graphs? One is the surface temperature trend, the other is CO2 emissions with future emission senerios. Is there any mention of the troposphere in this discussion? Any other graphs showing temperatures other than surface temps? NO.

    Victor: Lack of basic reading skills abounds on this blog.

    And it most certainly does, at least by one clueless arrogant fool who is totally incapable of reading comprehension and learning.

  15. 115
    nigelj says:

    There must be a jar of dunning kruger pills around somewhere, and Victor swallowed the whole lot.

  16. 116
    nigelj says:

    Actually interestingly enough J Hansen thinks global warming has accelerated recently, when you look at the last 6-7 years, rather than just the two el ninos alone:

    http://www.columbia.edu/~jeh1/mailings/2020/20201214_GlobalWarmingAcceleration.pdf

    —————–

    Victor drinks deeply from the cup of Dunning Kruger, I think.

  17. 117
    Victor says:

    109 jgnfld says:

    Re. kia and “So what are you implying? The satellite records are to be ignored?

    V: Actually I was the one who said that, not kia.

    j: Nope. What is implied is that the satellite record shows the temps in a region where people mostly cannot live and where theory and observation both say that warming is NOT concentrated. It also shows even more cooling at higher elevations, just as the models predict.

    The satellite record is fine for what it is and it corroborates warming just fine.

    What it isn’t, however is what YOU keep “implying” it is. It is neither more accurate of surface conditions than direct surface measurements, nor more reliable than surface measurements (less so, actually for a number of reasons), nor the best indicator of conditions at the surface as it simply does not measure temps at he surface.

    V: The satellites record temps from the lower troposphere, and yes, that’s expected to be cooler than the surface temps. Nevertheless, if elevated CO2 levels produce an increased warming trend at the surface one would expect a similar trend to appear in the troposphere — only that’s not the case. And yes, they are more reliable as there is no need for all the many corrections require by the surface data — corrections which might or might not be needed. If those corrections were meaningful, and the relation between CO2 and global temperatures were what is being claimed, the two should reflect one another. Only they don’t.

  18. 118
    Victor says:

    112 – CCHolley: “The trend line is THE TREND LINE which was done by doing a linear regression. It is a statistically valid trend line which is meant to show the trend for the period…the period for which temperatures started to rise to the present. It doesn’t fool the eye because it is actually THE TREND.”

    V: One can select any two endpoints and a linear regression will produce a trend line connecting them. So what?

    CC: [corrected version] Note from the NASS GISS data the anomaly for 1979 was 0.16 C, for 1998 it was 0.61 C, and for 2015 it was 0.9 C. For the period 1979 to 1998 that’s a 0.45 C difference and NOT 0.8 C and for 1998 to 2015 that’s 0.29 C and NOT *only* 0.2 C. So again, Victor is seeing things.

    V: Take another look at the graph YOU posted: https://climate.nasa.gov/system/internal_resources/details/original/1987_yearly_temperature_anomalies_from_1880_to_2019.jpeg

    See the numbers arranged vertically at the left, representing the temperature anomalies for that particular graph? Those are the numbers I used. And yes, according to those numbers we see the differences to which I referred, .8 vs. .2.

    CC: This has been rehashed so many times on this site and even by Tamino it has became such a bore.

    https://tamino.wordpress.com/2018/06/30/weak-sauce-from-climate-deniers/

    V: Tamino’s analysis is seriously flawed. I pointed out the problem in a comment when he first posted his little diagrams back in 2014, but my comment conveniently disappeared. I decided to include a critique of Tamino’s post in my book “The Uncertain Science of Climate Change” — which I assume you have read :-)

    For your benefit I’ve reproduced that segment in a blog post, which you are free to study — if you dare. His error should be obvious:

    http://amoleintheground.blogspot.com/2021/05/thoughts-on-climate-change-part.html

  19. 119
    Victor says:

    Correction: the title of my book is “The Unsettled Science of Climate Change”. Still available at Amazon: https://www.amazon.com/Unsettled-Science-Climate-Change-Critical-ebook/dp/B00YOARTPQ

  20. 120
    Victor says:

    116 nigelj says:

    Actually interestingly enough J Hansen thinks global warming has accelerated recently, when you look at the last 6-7 years, rather than just the two el ninos alone:

    http://www.columbia.edu/~jeh1/mailings/2020/20201214_GlobalWarmingAcceleration.pdf

    V: Interesting to note the emphasis Hansen places on “aerosol forcing.” Once again I’ll direct you to a recent blog post in which that theory is decisively put to rest:

    http://amoleintheground.blogspot.com/2021/03/thoughts-on-climate-change-part-10.html

  21. 121
    nigelj says:

    Victor @117

    “Nevertheless, if elevated CO2 levels produce an increased warming trend at the surface one would expect a similar trend to appear in the troposphere — only that’s not the case.”

    It is the case. The trend is similar. Look at the composites people have already posted. To Victor ‘similar’ appears to mean ‘identical’.

    “And yes, they (satellite data) are more reliable as there is no need for all the many corrections require by the surface data — corrections which might or might not be needed.

    Satellite data are not more reliable than surface records using thermometers. Victor probably doesn’t know that satellites don’t have thermometers. They sense temperatures indirectly and require massive analysis and have had a significant number of corrections. They do provide useful and valid temperature information but they are just not quite as accurate as the surface record with its thermometers. Refer:

    https://skepticalscience.com/print.php?r=466

    https://en.wikipedia.org/wiki/Satellite_temperature_measurements#:~:text=Measurements-,Satellites%20do%20not%20measure%20temperature%20directly.,obtain%20indirect%20inferences%20of%20temperature.

    https://www.carbonbrief.org/major-correction-to-satellite-data-shows-140-faster-warming-since-1998#:~:text=After%20correcting%20for%20problems%20caused,times%20larger)%20warming%20since%201998.

    “Corrections that might or might not be needed?”

    Come on Victor. That is empty rhetorical sophistry. Everyone can see this Reasons why the data need correcting are easily found:

    https://skepticalscience.com/understanding-adjustments-to-temp-data.html

    The corrections to the global surface record have actually adjusted warming DOWN:

    https://www.carbonbrief.org/explainer-how-data-adjustments-affect-global-temperature-records

    If Victor had bothered to do some basic investigation on all this (Im just a frigging layperson), he wouldn’t be making such silly inferences.

    ——————————

    Victor @120

    Sorry but while its understandable to question the issue, your views on aerosols are not evidence based. Aerosols are known to reflect solar radiation (to put it simply) and so have a cooling effect from 1) laboratory studies, 2) observational evidence near centres of industry, and 3)evidence of short term cooling after volcanic eruptions. This is three separate lines of evidence. For this reason its not controversial, even with the small number of climate scientists who are sceptics. Only Victor rants on endlessly about this, unable to admit to himself he has misinterpreted the issue and unable to move on. Which I find intriguing.

    —————————

    Ok time to stop feeding this dunning kruger afflicted troll. I’m done.

  22. 122
  23. 123

    KIA–

    …if elevated CO2 levels produce an increased warming trend at the surface one would expect a similar trend to appear in the troposphere — only that’s not the case.

    Oh, do tell:

    https://www.woodfortrees.org/plot/rss/mean:13/plot/rss/trend/plot/gistemp/from:1975/mean:13/plot/gistemp/from:1975/trend

    And a bonus question–assuming contrafactually that 1) there was no connection between GHGs and warming, and 2) there really wasn’t a similar trend between surface and lower troposphere–then what physics would account for that, given that there is this well-validated thing called a “lapse rate?”

  24. 124
    Astringent says:

    V@120 more or less sums up his idiocy Once again I’ll direct you to a recent blog post in which that theory is decisively put to rest: . Blog posts are blog posts. Scientific theories get decisively put to rest, or not, in high impact peer reviewed journals. It’s a bit like ‘my eye sees/doesn’t see a trend’ vs ‘a trend line was interpolated using linear regression’.

  25. 125

    V 117: [satellite temperatures] are more reliable as there is no need for all the many corrections require by the surface data

    BPL: That’s completely wrong. Satellite temperatures must be constructed with great difficulty and a large amount of calculation from electronic data, and studies using them have often gotten the temperatures completely wrong in the past, requiring all kinds of corrections. See, just for one example:

    Santer, B.D., T.M.L. Wigley, G.A. Meehl, M.F. Wehner, C. Mears, M. Schabel, F.J. Wentz, C. Ammann, J. Arblaster, T. Bettge, W.M. Washington, K.E. Taylor, J.S. Boyle, W. Brüggemann and C. Doutriaux 2003. “Influence of Satellite Data Uncertainties on the Detection of Externally Forced Climate Change.” Science 300, 1280-1284.

  26. 126

    V 118: One can select any two endpoints and a linear regression will produce a trend line connecting them

    BPL: You NEVER construct a linear regression from two endpoints alone. You have to use ALL the points, or it’s not a linear regression, by definition. Your quote shows you completely misunderstand what a linear regression is, and what a trend is as well. Will you for Christ’s sweet sake crack an introductory statistics textbook and READ THROUGH IT AND WORK THE PROBLEMS! As is you sound like a creationist talking about biology. You’re just embarrassing yourself.

  27. 127
    Victor says:

    121 nigelj says:

    Victor @117

    “Nevertheless, if elevated CO2 levels produce an increased warming trend at the surface one would expect a similar trend to appear in the troposphere — only that’s not the case.”

    n: It is the case. The trend is similar. Look at the composites people have already posted. To Victor ‘similar’ appears to mean ‘identical’.

    V: I was comparing the UAH data with the newly revised NASA data, and yes, there is a considerable difference, as can easily be seen by comparing UAH6 (https://www.woodfortrees.org/plot/uah6/from:1970/to:2020/mean:12) with the graph displayed by Stefan, above.

    As for the rest, I’ll concede that the issues with the satellite record generally are more complex than I thought. So thanks for correcting me. However, that does not change my skepticism regarding the revisions to the ground data as supervised by Karl, a well-known AGW advocate. Any revision of long-standing evidence should be done by researchers with no skin in the game.

    n: Victor @120 Sorry but while its understandable to question the issue, your views on aerosols are not evidence based. Aerosols are known to reflect solar radiation (to put it simply) and so have a cooling effect from 1) laboratory studies, 2) observational evidence near centres of industry, and 3)evidence of short term cooling after volcanic eruptions. This is three separate lines of evidence. For this reason its not controversial, even with the small number of climate scientists who are sceptics. Only Victor rants on endlessly about this, unable to admit to himself he has misinterpreted the issue and unable to move on. Which I find intriguing.

    V: Did you bother to read my blog post? If so you’d know that I’m perfectly aware of the cooling effect of aerosols. That was NOT the point. Please do click on that link and read the post.

  28. 128
    Victor says:

    124 Astringent says:

    V@120 more or less sums up his idiocy Once again I’ll direct you to a recent blog post in which that theory is decisively put to rest: . Blog posts are blog posts. Scientific theories get decisively put to rest, or not, in high impact peer reviewed journals. It’s a bit like ‘my eye sees/doesn’t see a trend’ vs ‘a trend line was interpolated using linear regression’.

    V: The data I presented speaks for itself. If you want to accuse me of cherry picking then, by all means, offer some contradictory data, if you can find it.

    125 Barton Paul Levenson says:

    V 117: [satellite temperatures] are more reliable as there is no need for all the many corrections require by the surface data

    BPL: That’s completely wrong. Satellite temperatures must be constructed with great difficulty and a large amount of calculation from electronic data, and studies using them have often gotten the temperatures completely wrong in the past, requiring all kinds of corrections.

    V: I stand corrected on that one. See my reply to nigelj, above.

    126
    Barton Paul Levenson says:

    V 118: One can select any two endpoints and a linear regression will produce a trend line connecting them

    BPL: You NEVER construct a linear regression from two endpoints alone. You have to use ALL the points, or it’s not a linear regression, by definition. Your quote shows you completely misunderstand what a linear regression is, and what a trend is as well. Will you for Christ’s sweet sake crack an introductory statistics textbook and READ THROUGH IT AND WORK THE PROBLEMS! As is you sound like a creationist talking about biology. You’re just embarrassing yourself.

    V: Well duh! Constructing a linear regression from two endpoints is NOT the same as simply drawing a line connecting them, as you seem to think I believe. Naturally you use all the data in between. My point was that such a regression can be constructed from any two points and it will produce a trend line.

  29. 129

    V 127: I was comparing the UAH data with the newly revised NASA data, and yes, there is a considerable difference, as can easily be seen by comparing UAH6

    Year UAH GISS
    1979 -0.357 0.16
    1980 -0.180 0.26
    1981 -0.257 0.32
    1982 -0.410 0.14
    1983 -0.186 0.31
    1984 -0.379 0.16
    1985 -0.489 0.12
    1986 -0.358 0.18
    1987 -0.098 0.32
    1988 -0.071 0.39
    1989 -0.345 0.27
    1990 -0.128 0.45
    1991 -0.104 0.41
    1992 -0.416 0.22
    1993 -0.347 0.23
    1994 -0.191 0.32
    1995 -0.065 0.45
    1996 -0.158 0.33
    1997 -0.148 0.47
    1998 0.331 0.61
    1999 -0.132 0.39
    2000 -0.158 0.40
    2001 -0.032 0.54
    2002 0.076 0.63
    2003 0.048 0.62
    2004 -0.033 0.54
    2005 0.052 0.68
    2006 -0.025 0.64
    2007 0.025 0.67
    2008 -0.232 0.54
    2009 -0.048 0.66
    2010 0.178 0.72
    2011 -0.115 0.61
    2012 -0.087 0.65
    2013 -0.001 0.68
    2014 0.042 0.75
    2015 0.134 0.90
    2016 0.385 1.01
    2017 0.257 0.92
    2018 0.104 0.85
    2019 0.289 0.98
    2020 0.362 1.02

    r = 0.917
    r^2 = 0.841
    p < 0.00001

    Let him with ears to hear, hear.

  30. 130

    V 128: Constructing a linear regression from two endpoints is NOT the same as simply drawing a line connecting them, as you seem to think I believe. Naturally you use all the data in between. My point was that such a regression can be constructed from any two points and it will produce a trend line.

    BPL: Your point was WRONG. A line drawn between two endpoints is NOT a “linear regression.” It’s linear, but it is NOT a “regression.” And you still don’t understand what a “trend” is. Determining a trend requires a true linear regression, not just a line.

  31. 131
    MA Rodger says:

    I see the troll Victor Grauer is continuing to act like he is holding court down this thread. I don;t think that is appropriate.
    Give Victor hasn’t managed to learn anything useful over the last seven years since his first appearance here on the RealClimate comment threads, he is evidently either incredibly stupid, suffering from delusions of being not-stupid, is in deep denial over AGW or is simply a troll who delights in poking his nonsense into RealClimate’s comment threads. (As a measure of his nonsense, Victor the Troll has provided 20% of the business down the Bore Hole through his time here.)

    Working backwards up-thread….

    Victor the Twit @128,

    “Well duh! Constructing a linear regression from two endpoints is NOT the same as simply drawing a line connecting them, as you seem to think I believe. Naturally you use all the data in between. My point was that such a regression can be constructed from any two points and it will produce a trend line.”

    Well duh!!! Whether or not the cretin thinks you can cherrypick two points in a series, draw a line between the two while ignoring any intermediate points and then call it “a regression”, he still manages to happily carries out such such a procedure, brings the results here and is now happily telling us it is a “regression.” Yet calculating a “regression” with just two data points is mathematically impossible and to ignore intermediate points is (on methodological grounds) simply fake analysis.

    Victor the Halfwit @127&128,

    “Did you bother to read my blog post? If so you’d know that I’m perfectly aware of the cooling effect of aerosols. That was NOT the point. Please do click on that link and read the post.”
    “The data I presented
    [within the linked post] speaks for itself. If you want to accuse me of cherry picking then, by all means, offer some contradictory data, if you can find it.”

    This silly blog post by the fool was presented @120, apparently not for the first time (although I don’t see it in this thread – the only place I can see is the Bore Hole) and the imbecile repeatedly insists folk read it. Gobshite Grauer tells us it is some sort of decisive’ analysis but, surprise surprise, it i’n’t!!!

    The thesis presented tells us that CO2 forcing is warming and global but if this is masked by cooling aerosol forcing over, say 1940-1979, aerosol forcings which are not so global being short-lived in the atmosphere, then places like the Arctic, Antarctic, Africa, Madagascar, Siberia, Afghanistan, Burundi, Haiti, Kyrgyzstan & New Caledonia where there was none of the industrial pollution and associated aerosol emissions would show none of the cooling from these aerosols. But a set of graphics presented in the moron’s blog show the cooling is present in all these locations. So this is proof-positive but only to demonstrate that the lunatics think they can run the asylum better than the grown-ups.

    Victor the Cretin @127,

    “I was comparing the UAH data with the newly revised NASA data, and yes, there is a considerable difference, as can easily be seen by comparing UAH6 (https://www.woodfortrees.org/plot/uah6/from:1970/to:2020/mean:12) with the graph displayed by Stefan, above.”

    The dullard doesn’t do any comparison. Had he, he would have provided an appropriate WoodForTrees graphic, one which shows the “considerable difference” between different TLT satellite data sets, these being differences far greater than the differences between the evidently-more-dependable SAT data sets.

  32. 132
    Victor says:

    I was wondering when my long-time “fan” Mr. Rodger would finally show up on this thread to amuse us with his block headed pedantry.

    131 MA Rodger says:

    I see the troll Victor Grauer is continuing to act like he is holding court down this thread. I don;t think that is appropriate.

    V: I’m not “holding court.” I’m simply responding to the posts of others.

    MR: Victor the Twit @128,

    “Well duh! Constructing a linear regression from two endpoints is NOT the same as simply drawing a line connecting them, as you seem to think I believe. Naturally you use all the data in between. My point was that such a regression can be constructed from any two points and it will produce a trend line.”

    Well duh!!! Whether or not the cretin thinks you can cherrypick two points in a series, draw a line between the two while ignoring any intermediate points and then call it “a regression”, he still manages to happily carries out such such a procedure, brings the results here and is now happily telling us it is a “regression.” Yet calculating a “regression” with just two data points is mathematically impossible and to ignore intermediate points is (on methodological grounds) simply fake analysis.

    V: MR, like so many others on this blog, insists on seeing what he wants to see rather than what is actually there on the page. So once again, let me insist: I’m NOT talking about “just two data points” but the full range of data between two arbitrarily selected points. For example, from 1935 to 2012: https://www.woodfortrees.org/plot/gistemp/from:1935/to:2012/plot/gistemp/from:1935/to:2012/trend See the line?

    Or let’s say, from 1943 to 1991: https://www.woodfortrees.org/plot/gistemp/from:1943/to:1991/plot/gistemp/from:1943/to:1991/trend See the line?

    How about 1940 to 1979: https://www.woodfortrees.org/plot/gistemp/from:1940/to:1979/plot/gistemp/from:1940/to:1979/trend

    Get it?

    MR: Victor the Halfwit @127&128,

    “Did you bother to read my blog post? If so you’d know that I’m perfectly aware of the cooling effect of aerosols. That was NOT the point. Please do click on that link and read the post.”
    “The data I presented [within the linked post] speaks for itself. If you want to accuse me of cherry picking then, by all means, offer some contradictory data, if you can find it.”

    MR: This silly blog post by the fool was presented @120, apparently not for the first time (although I don’t see it in this thread – the only place I can see is the Bore Hole) and the imbecile repeatedly insists folk read it. Gobshite Grauer tells us it is some sort of decisive’ analysis but, surprise surprise, it i’n’t!!!

    The thesis presented tells us that CO2 forcing is warming and global but if this is masked by cooling aerosol forcing over, say 1940-1979, aerosol forcings which are not so global being short-lived in the atmosphere, then places like the Arctic, Antarctic, Africa, Madagascar, Siberia, Afghanistan, Burundi, Haiti, Kyrgyzstan & New Caledonia where there was none of the industrial pollution and associated aerosol emissions would show none of the cooling from these aerosols. But a set of graphics presented in the moron’s blog show the cooling is present in all these locations. So this is proof-positive but only to demonstrate that the lunatics think they can run the asylum better than the grown-ups.

    V: Once again Mr. R twists himself into a pretzel in a vain effort to distort my argument. The evidence presented in that blog post demonstrates the lack of any underlying warming in the regional graphs I reproduced. The notion that industrial aerosols could have a cooling effect in regions where no industrial activity was taking place demonstrates how little MR understands about this issue.

  33. 133
    Barry Finch says:

    @131 MA Rodger I think “Victor the Twit @128” don’t know the difference between stating:
    “a linear regression from two endpoints” and stating
    “a linear regression between any start and end” is all that is.
    Persons who’ve never studied any science or mathematics also tend to get their worms wring.

  34. 134
    CCHolley says:

    Re. Victor

    We have a blog post by Stefan that is about the possibility of holding temperature rise to under 1.5 degrees centigrade. Stefan uses the NASS GISS instrumental surface temperature record for the past 50 years to create a statistical trend for the purpose of projecting warming going forward—an appropriate approach since it is the future of instrumental surface temperature rise that he is discussing.

    Yet Victor seems to think the trend line produced for the past 50 years is *misleading* because it gives the appearance that the warming was “steadily increasing.” WTF, what does that even mean? A trend is simply an upwards or downward shift in a data set over time—a multivariate data set. It allows you to predict what might happen in the future over time. The trend doesn’t care whether it is “steadily increasing”, it is simply the trend. Stefan does exactly what one would be expected to do to project the warming forward to help establish when in time the 1.5 degrees will be reached if the status quo remains the same, yet again Victor attacks Stefan’s *trend* as misleading. Why? Why? Why does he do this? Especially since Victor’s attack has ABSOLUTELY NOTHING to do with what Stefan is trying to do. NOTHING AT ALL.

    Throughout this string Victor goes off on multiple tangents bringing in irrelevant stuff–raw data, satellite temperature constructs, aerosols, etc. etc. etc. which again have NOTHING to do with Stefan’s blog post nor the subject at hand—limiting global instrumental temperature rise to under 1.5 degrees C.

    Why? Because Victor is an egomaniacal, deluded, nutcase who thinks he is smarter than everyone else including the highly educated, highly intelligent professional scientists that actually work in climate science and its related scientific fields. This while he has repeatably shown that he is totally incapable of understanding statistical methods, basic science, and even what the original blog post was all about. It is absolutely amazingly astounding how incapable the deluded Victor is of self reflection and in judging his own capabilities. Look at all of his baseless claims and how he brags about what he believes are his *accomplishments* related to climate science. He wrote a book! He is brilliant!

    What a joke.

  35. 135
    Barry Finch says:

    @36 John Monro Your “climate could quickly .. I look at Arctic Ice and the reduction of summer time ice are and the consequent changes in the planet’s albedo”.
    ______
    Your starting point on Arctic Ocean sea ice is the open-source 7-pages paper “Radiative Heating of an Ice-Free Arctic Ocean” by Kristina Pistone, Ian Eisenman and Veerabhadran Ramanathan Accepted article online 20 JUN 2019 AGU100 Download from https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019GL082914
    ______
    Keep reading it repetitively until you understand it but start at the nice pictorial “Figure 3” which tells us exactly what you were asking: — For each month separately from March to September it tells us exactly how much global warming is to be caused by loss of all ice throughout that one month over the 100 years following the ice loss. It indicates a total warming of +0.53 degrees over the 100 years (“0.71 W/m2 relative to the 1979 baseline state” in the paper Abstract) following the permanent ice loss for all months, so with the winter ice all melted away by late March, the entire ocean, every year, adds to +0.53 degrees “extra” (very wrong word I’m using) global warming over the 100 years following is stated in that paper (and I agree with Kristina et al (from CERES and modeling) because I did calculations over 300 hours of work 3-10 months before that paper appeared and I got +0.55 degrees “extra” global warming over the 100 years following). However, the paper states that 0.21 * 43% = 0.09 degrees (that’s rough) of that global warming already happened from 1979 to 2016 (and another climate scientist Peter Wadhams also alludes to that with “the ice loss since 1979 had made a huge 25% of the warming of CO2 and land snow another huge 25% !”. So, there’s now +0.44 degrees of “extra” (highly-incorrect word) global warming available over the 100 years following no Arctic Ocean sea ice in late March every year. The rate at which the +0.44 degrees occurs depends on global ocean mixing as all surface-air temperature change rates depend on global ocean mixing, which is so totally overwhelming that you could pretty-much say that all rates of everything depend on global ocean mixing once you get past a 12-month time scale being considered (clouds are big for monthly change noise) and be >90% correct in saying that.
    ———–
    Your ““tipping points” have been passed?…. could well cause a non-linear increase in global temperature”. You don’t understand. There’s ALREADY GOING ON a non-linear increase in global temperature (Stefan’s fitting of a straight line is incorrect). The 2nd derivative has been +0.06 degrees / decade**2 and I calculated that from the global heater 24 months ago and came across confirmation 12 months ago that global warming had increased by +0.06 degrees / decade to the most recent decade from the prior decade. THE GLOBAL HEATER HAS BEEN RELELNTLESSLY INCREASING, AND IT’S STARING ALL OF YOU RIGHT IN THE FACE FOR MORE THAN A DECADE. ONLY A HEATER HEATS AND ALSO A HEATER CAN’T AVOID HEATING, IT’S WHAT IT DOES.
    ——————-
    If you don’t study the global heater then you know nothing at all. If you start in the middle by looking at a Global Mean Surface Temperature anomaly (GMST) plot and then try to think forwards to some conclusions and simultaneously backwards to energy imbalance (sorry Stefan but it’s physical reality) then you’ll be driving for groceries or vacation by starting half way from your home and intermittently driving to your destination and your home, it’ll be a big mess. If surface-air increase rates interest you then you MUST study from the global heater and ocean mixing working forward only, and not working backwards by making inane, senseless, clearly mainingless statements like “The heat went into the oceans instead of causing warming” (if the ocean slows warming then it’s cold deep “heritage” water coming up that did that, not warm water going down, as Stefan knows, he’s an oceanographer). Scientific study is hard work consuming many hours (I spent 2,300 hours of hobby time on it) and completely different from and separate from the parroting of the preferred memes and the most trendy and popular memes, as you did @36 John Monro, totally un-quantified. Start with the global heater study (called “Ocean heat content” + 5%) and move to reading “Radiative Heating of an Ice-Free Arctic Ocean”. Learn something, it’s fun.
    ————-
    —- Note above “”extra” (highly-incorrect word) global warming” It’s only “extra” to whatever extent is incompletely assessed as a feedback by climate models, so if climate models have had open ocean at 70% of the actual open ocean then only the other 30% of global warming is “extra” and the big 70% (just an example) is already right there in those CMIP5 & CMIP6 projections that the coal/oil shills like Victor Graueueueur always say are “over-heated”. I completely made up 70% for example because I’ll not divert to searching my computer files for a few hours to find the actual Arctic Ocean sea ice extent CMIP5 modeling because comments on the Interweb just sink into the abyss of drivel anyway and serve no purpose. Forcing/feedbacks apparently are:
    100% “greenhouse gases (GHGs)” +/- Sun (very-multi-decadal-century+) and +/- Volcano +/- ocean (internal) (annual, short decadal, not much time for feedback)
    100% Pathetically-mixed GHG water vapour (H2O gas) feedback
    25% Arctic Ocean sea ice extent reduction albedo reduction
    25% Arctic region snow/ice reduction albedo reduction
    20% Something(s) maybe some cloud changes
    ———–
    270% Total apparent forcing/feedback factor FOR THE PRESENT GENERAL TYPE OF CLIMATE NOT A 1,300 PPMV C02 AND NOT A GLACIATION
    The 270% calculates to a climate sensitivity of 3.27 degrees (0.88 degrees / (w/m**2)) and Andrew Dessler says the brainy scientists are thinking 3.3 degrees so my own naive calculations are in the same ball park. Also, notwithstanding my “NOT A GLACIATION” a lady scientist just assessed 0.84 degrees / (w/m**2) for latest de-glaciation. My own calculation is that an average of 0.75 degrees / (w/m**2) has happened 1750-2020 (climate sensitivity of 2.79 degrees) but of course some feedbacks might be >linear to whatever small moderate degree without any “tipping points”. I’ve mentioned the present +0.20 degrees / decade +0.06 degrees / decade**2 2nd order GMST trend that I calculated a few months back.
    ———————–
    If anybody is interested at all in physical science then it’s CRUCIAL to separate scientific study from handy catch phrases and memes that are entirely irrelevant to physical science and are for the social “sciences” (ahem ahem). “Blue Ocean Event”, “Show us the RAW data”, “987 catastrophic self-reinforcing positive feedbacks”, whatever, all of them, everywhere, they are terrific laudable stuff, banner waving, having absolutely nothing whatsoever to do with physical science, which is always quantified to be of any use whatsoever. What is entirely to do with physical science is “Radiative Heating of an Ice-Free Arctic Ocean” by Kristina Pistone, Ian Eisenman and Veerabhadran Ramanathan, and lots of others (even Stefan’s).

  36. 136

    #131, MAR–

    Indeed, the record does show differences between TLT and SAT data, and between the different TLT sets (i.e., RSS or UAH).

    But it’s not just that the difference between the latter pair is simply “greater” than between the SAT datasets. (That would be very surprising, because RSS and UAH mostly use the same underlying radiance measurements!) My take–and I think it’s objectively pretty supportable–is that the relatively high frequency (that is, shorter time scale) features of the TLT data are indeed pretty similar–BUT in lower frequency realms (including the trend over the span of the data) it’s the RSS and the SAT datasets that are similar:

    https://www.woodfortrees.org/plot/uah6/from:1979/to:2020/mean:12/plot/gistemp/from:1979/to:2020/mean:12/plot/rss/from:1979/to:2020/mean:12/offset:0.25/plot/best/from:1979/to:2020/mean:12

    In other words, the UAH data, upon which Victor is hanging his metaphorical hat, is the outlier over the longer term. That would still be broadly true if you add in HADCRUT data:

    https://www.woodfortrees.org/plot/uah6/from:1979/to:2020/mean:12/plot/gistemp/from:1979/to:2020/mean:12/plot/rss/from:1979/to:2020/mean:12/offset:0.25/plot/best/from:1979/to:2020/mean:12/plot/hadcrut4gl/from:1979/to:2020/mean:12/offset:0.1

    Here’s another view of the same data, emphasizing the point in a different way:

    https://www.woodfortrees.org/plot/uah6/from:1979/to:2020/mean:12/plot/gistemp/from:1979/to:2020/mean:12/plot/rss/from:1979/to:2020/mean:12/offset:0.25/plot/best/from:1979/to:2020/mean:12

    By intention or not, UAH understates warming relative to all other datasets. That includes the NOAA data, which Stefan used, but which aren’t on WFT.

  37. 137
    nigelj says:

    Victor @132 pontificates: “The evidence presented in that blog post demonstrates the lack of any underlying warming in the regional graphs I reproduced. The notion that industrial aerosols could have a cooling effect in regions where no industrial activity was taking place demonstrates how little MR understands about this issue.”

    The reason the whole earth cooled mid last century is because the aerosols spread from industrial centres right around the globe. They spread vast distances as below:

    https://earthobservatory.nasa.gov/features/Aerosols

    “Depending on the season and weather conditions, surges of aerosols can make their way into the atmosphere almost anywhere on Earth….Although most aerosols remain suspended in the atmosphere for short periods—typically between four days and a week—they can travel vast distances. Particles moving with the atmosphere at 5 meters (16.4 feet) per second will travel thousands of kilometers in a week… ( on air currents etc). ”

    So theres no great mystery why most of the earth cooled mid last century due to industrial aerosols. Then warming resumed about 1975 as filters were used and CO2 had accumulated to very significant levels in the atmosphere. But I fully expect Victor will go on ranting about his suspicions until hell freezes over.

  38. 138
    MA Rodger says:

    Kevin McKinney @136,
    There is a view that RSSv4 presents a better measure of TLT than UAHv6 because its global values show a trend close to the SAT global trend. But I think we should be cautious with satellite TLT data.

    Simplistically, think back to when it was RSSv3.3 and UAHv5.6 – the roles were were reversed with UAHv5.6 running close to HadCRUT4 trends as this WoodForTrees plot shows and RSSv3.3 was the go-to temperature series for denialists. With the arrival of the new RSSv4 consigning the lacklustre trends of v3.3 to history, the poor denialists were at a lose for a while before turning to UAHv6.0. So could there by further major revisions of these TLT data sets?

    But also, if you start looking at RSSv4 numbers at a NH/SH level (or some other sub-global level), the fit with SAT becomes less “similar”. (I don’t immediately see a graphic on-line demonstrating this but from memory, is it quite dramatic.)

  39. 139
    MA Rodger says:

    When @131 I described Victor the Troll as “holding court,” it was in the sense that he had folk here trying to explain his egregious errors to him as though he were some rational being. Victor is a deeply stupid man who is wedded to the view that the wobbles in the temperature records (or their proxies) demonstrate a lack of correlation between global temperature and CO2 forcing; so AGW must be entirely fake. Trying to explain rationally to such a one is a complete waste of time and effort. Rather, I would suggest a better approach is to demonstrate what a fool the idiot is by showing how wrong he is.

    Thus @132 Victor tries to demonstrate how he does understand OLS by providing a trio of links to WoodForTrees OLS while ignoring the episode up-thread @107 when he tried to use (seemingly for an identical purpose) three random annual GISS values he had misread from this graphic to argue that there was some sort of significant change in the rate of AGW between 1979-98 and 1998-2015. The graphic in the OP above by Stephan could not be used as a source of these data because, while it is “based on the same data,” is “not the same.” Apparently Stephan’s graphic:-

    “creates the impression of a continuous linear progression over the last 50 years, while one can discern in [Stephan’s] version … a clear contrast between the ranges of 1979 to 1998 and the very different period 1998 to 2015. Much of the difference is obscured by the trend line appearing in Stefan’s version which fools the eye into seeing a simple continuity, obscuring the difference that’s so apparent when the trend line is removed.”

    Of course, that nonsense is now all forgotten and now it’s all now mindless regression regression regression using WoodForTrees although if we revisit that 1979-98/1998-2015 thing, the WoodForTrees regressions are is not exactly supportive of the brainless troll’s ‘pause’ theory.

    Also @132 Victor the Troll attempts to defend the puerile nonsense on some pathetic blogpage he’s created. If the fool were worth educating in the operation of aerosols within AGW, perhaps reference to the two plates of Fig 11.2 in Kreidenweis (219) ‘100 Years of Progress in Cloud Physics, Aerosols, and Aerosol Chemistry Research’ would be a useful start. We could even point to the locations of places like Haiti or Kyrgyzstan, or anywhere as Fig 11.2 is a global map. And as a second step, there is the point that you don’t actually have to be in the fire to be warmed by it.
    But such ideas are too contrary for the likes of Victor the Troll who will clatter round in a strop a while under his bridge before popping up with his fix to this attack on his belief system – that is to spout a further round of nonsense to support his crazy beliefs.

  40. 140
    MA Rodger says:

    Kevin McKinney @136,
    Further to previous responding comment, I’ve dug out & up-loaded this graphic which plots GISS SAT and RSS/UAH TLT data 1979-2019 by hemisphere. All three GISS, RSS & UAH show greater NH warming than SH warming, but with GISS showing NH warming perhaps 250% of SH warming with less of a difference for the TLT records – RSS 165% & UAH 140%. While RSS NH tracks GISS NH quite closely with UAH NH showing far less warming, it is UAH SH that tracks GISS SH even more closely with RSS SH showing far more warming.
    Of course, TLT & SAT are measuring different things so it is possible that one or part of one of these two TLT series is accurately recording what it is attempting to measure.

  41. 141
    Barry Finch says:

    @136 Kevin McKinney Well, Roy Spencer’s UAH TLT rate 1979-2015 changed from +0.140 degrees / decade that he had with V5.6 to +0.114 degrees / decade with his latest (so far) V6.0 when he updated a few years back, only 81% of his former certified trend. I was thinking of studying that a bit but decided it’s too time-costly and not very relevant when there’s Wonky Jet Stream and AMOC to ponder. To be fair RSS also made big trend changes with their version updates. I think I recall UAH once showing more warming than RSS, then they simply traded places big time. I thought I noticed a strange thing in which UAH & RSS only deviated following any El Nino, (with UAH always remaining then another step change below RSS) but I’m not sure and if RSS can only comment (paraphrasing) “They make different assumptions than ours” about the technical reasons then it bodes poorly for me ever working it out.

  42. 142
    Barry Finch says:

    I recall that Kevin Cowtan and Robert Way ~7 years ago assessed a correction of +0.07 degrees global over ~1996-~2013 (17 years) needed to HadCrut4 due to its poor representation of the additional Arctic warming, using satellite data to infill/adjust the poorly-represented Arctic region by some algorithm. I don’t know whether that’s been incorporated into later HadCrut4 versions or HadCrut5 and I recall seeing a recent plot with HadCrut and a Cowtan & Way plotted separately but I’m very hazy on that because it’s not part of the science I’ve been studying.

  43. 143

    I think I’m beginning to see that Victor and I were, to an extent, talking past each other. When he said “a linear regression between two endpoints,” he apparently meant “a linear regression between two points in time,” rather than “a line drawn from the first point to the second.” So his mistake wasn’t really a mistake, just misleading phrasing.

    He’s still wrong that any linear regression would show a trend, though; that depends on whether the slope of the line was statistically significant or not. Example: If the line is perfectly horizontal, the slope is zero, and there’s no trend. Positive and significant is “a positive trend,” negative and significant is “a negative trend,” anything else is “no trend” or “not enough evidence for a trend.”

  44. 144
    MA Rodger says:

    Barry Finch @142,
    This CarbonBrief post from the end of last year describes the impact of the HadCRUT5 update which does include infilling methods not dissimilar to Cowtan & Way. The result sees HadCRUT5 showing reduced warming 1979-2000 (about -0.03ºC over the period) followed by an increased warming 2000-on (about +0.07ºC by 2010 and subsequent to 2015 wobbles adding a further +0.05ºC on top).

    As you rightly say, Cowtan & Way carried out an infill analysis on the HadCRUT4 series which showed +0.07ºC increased warming on HadCRUT4 (following some -0.02ºC reduced warming 1979-99), with this +0.07ºC post-2000 increased warming almost all appearing 2000-2010 and, after the last 10-year’s showing a bit of a temporary dip, is back showing a little above that +0.07ºC at the end of 2020.
    The linked CarbonBrief post shows both filled & non-filled HadCRUT5, the latter with +0.02ºC increased warming 2000-10 and an additional +0.05ºC 2010-18, this an amendment which would be not featuring in Cowtan & Way being based on HadCRUT4.

  45. 145
    Victor says:

    137 nigelj says:

    The reason the whole earth cooled mid last century is because the aerosols spread from industrial centres right around the globe. They spread vast distances as below:

    https://earthobservatory.nasa.gov/features/Aerosols

    “Depending on the season and weather conditions, surges of aerosols can make their way into the atmosphere almost anywhere on Earth….Although most aerosols remain suspended in the atmosphere for short periods—typically between four days and a week—they can travel vast distances. Particles moving with the atmosphere at 5 meters (16.4 feet) per second will travel thousands of kilometers in a week… ( on air currents etc). ”

    V: Yes, they can spread great distances, but as they do, they dissipate. The farther from the source of the pollution, the less the cooling effect.

    From the article you cited (see link above): “. . . unlike many greenhouse gases, aerosols are not distributed evenly around the planet, so their impacts are most strongly felt on a regional scale.”

    Also: “The distribution of anthropogenic aerosols’ climate effects depends on the geographic distribution of the aerosols themselves. Yet many scientific and policy discussions ignore the role of emission location when evaluating aerosols’ climate impacts. . . This suggests that climate accounting should differentiate between aerosols emitted from different countries and that aerosol emissions’ evolving geographic distribution will impact the global-scale magnitude and spatial distribution of climate change. . . Aerosols’ heterogeneous spatial distribution is recognized to influence their overall climate impact relative to more homogeneous climate forcers, like carbon dioxide.” (“Divergent global-scale temperature effects from identical aerosols emitted in different regions,” as published in Nature, August 2018)

    139 more foolishness from MAR:

    Also @132 Victor the Troll attempts to defend the puerile nonsense on some pathetic blogpage he’s created. If the fool were worth educating in the operation of aerosols within AGW, perhaps reference to the two plates of Fig 11.2 in Kreidenweis (219) ‘100 Years of Progress in Cloud Physics, Aerosols, and Aerosol Chemistry Research’ would be a useful start. We could even point to the locations of places like Haiti or Kyrgyzstan, or anywhere as Fig 11.2 is a global map. And as a second step, there is the point that you don’t actually have to be in the fire to be warmed by it.

    V: I called your bluff by finding the paper you (incorrectly) linked us to and studying the figure you referenced. Here it is:

    https://journals.ametsoc.org/view/journals/amsm/59/1/full-amsmonographs-d-18-0024.1-f2.jpg

    The map on the left represents greenhouse gas forcings, which as you can see are widely scattered around the globe. The map on the right represents “anthropogenic sulfate aerosol forcing”s (in blue) which, as indicated on the map, are centered in the industrial centers of eastern N. America, Europe and China, as one would expect. I fail to see how this map refutes anything in the blog presentation that’s so rattled MAR. Perhaps he would like to elaborate.

    And yes, “you don’t actually have to be in the fire to be warmed by it.” But the farther away you are, the less warmed you will be.

  46. 146
    Barry Finch says:

    Regarding some mention of GMST anomaly “pause” or “hiatus” (or slow down) between the big El Ninos 1997/8 and 2015/6 I came across a plot 8 years ago of easterly trade wind speed (stress) across the tropical Pacific Ocean from pre 1970 (I forget) to 2012 that indicated that wind speed had increased as a trend starting 1995 after a flat trend pre-1995 and by 2012 was 30% faster, which was ~1.0 m/s faster, by 2012. Since then I lethargically search rarely for an update post 2012 but never found anything. Here’s some quotes:
    ———
    Quote: “Atlantic warming turbocharges Pacific trade winds Date:August 3, 2014 Source:University of New South Wales. New research has found rapid warming of the Atlantic Ocean, likely caused by global warming, has turbocharged Pacific Equatorial trade winds. Currently the winds are at a level never before seen on observed records, which extend back to the 1860s. The increase in these winds has caused eastern tropical Pacific cooling, amplified the Californian drought, accelerated sea level rise three times faster than the global average in the Western Pacific and has slowed the rise of global average surface temperatures since 2001. It may even be responsible for making El Nino events less common over the past decade due to its cooling impact on ocean surface temperatures in the eastern Pacific. “We were surprised to find the main cause of the Pacific climate trends of the past 20 years had its origin in the Atlantic Ocean,” said co-lead author Dr Shayne McGregor from the ARC Centre of Excellence for Climate System Science (ARCCSS) atthe University of New South Wales.”
    —————-
    Quote: “The record-breaking increase in Pacific Equatorial trade winds over the past 20 years had, until now, baffled researchers. Originally, this trade wind intensification was considered to be a response to Pacific decadal variability. However, the strength of the winds was much more powerful than expected due to the changes in Pacific sea surface temperature. Another riddle was that previous research indicated that under global warming scenarios Pacific Equatorial Trade winds would slow down over the coming century. The solution was found in the rapid warming of the Atlantic Ocean basin, which has created unexpected pressure differences between the Atlantic and Pacific. This has produced wind anomalies that have given Pacific Equatorial trade winds an additional big push. “The rapid warming of the Atlantic Ocean created high pressure zones in the upper atmosphere over that basin and low pressure zones close to the surface of the ocean,” says Professor Axel Timmermann, co-lead and corresponding author from the University of Hawaii. “The rising air parcels, over the Atlantic eventually sink over the eastern tropical Pacific, thus creating higher surface pressure there. The enormous pressure see-saw with high pressure in the Pacific and low pressure in the Atlantic gave the Pacific trade winds an extra kick, amplifying their strength. It’s like giving a playground roundabout an extra push as it spins past.” Many climate models appear to have underestimated the magnitude of the coupling between the two ocean basins, which may explain why they struggled to produce the recent increase in Pacific Equatorial trade wind trends. While active, the stronger Equatorial trade winds have caused far greater overturning of ocean water in the West Pacific, pushing more atmospheric heat into the ocean, as shown by co-author and ARCCSS Chief Investigator Professor Matthew England earlier this year. This increased overturning appears to explain much of the recent slowdown in the rise of global average surface temperatures. Importantly, the researchers don’t expect the current pressure difference between the two ocean basins to last. When it does end, they expect to see some rapid changes, including a sudden acceleration of global average surface temperatures. “It will be difficult to predict when the Pacific cooling trend and its contribution to the global hiatus in surface temperatures will come to an end,” Professor England says.”
    —————-
    Recent intensification of wind-driven circulation in the Pacific and the ongoing warming hiatus
    Nature Climate Change 4, 222–227 (2014) doi:10.1038/nclimate2106 Received 11 September 2013 Accepted 18 December 2013 Published online 09 February 2014 Corrected online 14 February 2014
    Matthew H. England, Shayne McGregor, Paul Spence, Gerald A. Meehl, Axel Timmermann, Wenju Cai, Alex Sen Gupta, Michael J. McPhaden, Ariaan Purich & Agus Santoso Affiliations “Here we show that a pronounced strengthening in Pacific trade winds over the past two decades—unprecedented in observations/reanalysis data and not captured by climate models—is sufficient to account for the cooling of the tropical Pacific and a substantial slowdown in surface warming through increased subsurface ocean heat uptake”

  47. 147
    Richard Caldwell says:

    BPL: anything else is “no trend” or “not enough evidence for a trend.”

    RC: Yeah. Isn’t it “amazing” that “alarmists” like BPL include all the data and all interpretations of said data, while “deniers” like what’s-his-name feel zero reason to be objective?

    You’re a serious resource on this comment board, BPL. Not sure if that matters, but we have to deal with what is.

    Thanks, dude.

  48. 148
    Richard Caldwell says:

    KM: Well, you’re asking us to wade in deep waters, but if the paraphrase of the 2nd law of thermodynamics “You can’t break even” is correct, then I would say that yes, it applies in Hell.

    RC: iirc the temp of the universe is wayyyyyyy below freezing, and unless the expansion of the universe is reversed the universe’s temp *must* decrease, so, well, yeah, you’re right, assuming “Hell” is in this universe.

  49. 149
    Richard Caldwell says:

    Nigel: There must be a jar of dunning kruger pills around somewhere, and Victor swallowed the whole lot.

    RC: While I totally agree with your sentment, technically speaking there are unlimited supplies of said pills. Victor survives on a diet that consists primarily of said pills, but dude, there is an endless supply.

    Sucks, eh?

  50. 150
    Richard Caldwell says:

    CCHolly on Victor: What a joke.
    RC: So? Victor is an entertainer. He does his job (snaring the likes of you for grins and chuckles) quite well.

    Perhaps you should ponder the difference between science and entertainment? Because bitching about an entertainer because he isn’t a science guy (as he has adamantly stated a bazillion times) seems unwise to me

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