"Is Climate 'Lukewarmism' Legitimate?"

Guest post by David Middleton

A very thoughtful column by Ross Pomeroy at Real Clear Science…

Is Climate ‘Lukewarmism’ Legitimate?

To many, prominent writers Matt Ridley, Ross Douthat, and Oren Cass are a baffling bunch. They are the visible proponents of the position that climate change is real, manmade, and occurring as predicted by the Intergovernmental Panel on Climate Change (IPCC), yet it does not yet constitute a worrying or catastrophic problem. They are “lukewarmers.”

So what do we make of these climate change moderates, who do not hold the invalid, unevidenced opinions of those who deny the scientific consensus, yet at the same time, do not ascribe to the apocalyptic scenarios espoused by climate alarmists and the accompanying solutions to avert them?

As far as I can tell, lukewarmers’ views are legitimate. The mountains of evidence present in the most recent IPCC assessment report, comprising more than 9,200 peer-reviewed studies, cannot simply be cast aside as the product of a conspiracy or a statistical fluke of climate models. If lukewarmers accept the science, they are on solid ground.


To his credit, lukewarm New York Times columnist Ross Douthat agrees. “Every lukewarmer, including especially those in positions of political authority, should be pressed to identify trends that would push them toward greater alarmism and a sharper focus on the issue.”

In other words, they must recognize some level of evidence that will cause them to change their views. If they don’t, they have proven themselves not to be lukewarm moderates but dogmatic deniers.

Full Article on Real Clear Science

“Every lukewarmer, including especially those in positions of political authority, should be pressed to identify trends that would push them toward greater alarmism and a sharper focus on the issue.”

This is not a one-sided question. It should also be asked, “What trends would push a lukewarmer towards lesser alarmism and a sharper focus on the issue.”

For this lukewarmer, there is a level of evidence that would cause me to change my views.  This would be some level of evidence above…

Almost every catastrophic prediction is based on climate models using the RCP 8.5 scenario (RCP = relative concentration pathway) and a far-too high climate sensitivity. RCP 8.5 is not even suitable for bad science fiction. Actual emissions are tracking closer to RCP 6.0. When a realistic transient climate response is applied to RCP 6.0 emissions, the warming tracks RCP 4.5… A scenario which stays below the “2° C limit,” possibly even below 1.5° C.

Ensemble of RCP 4.5 models and observed temperatures ( Zeke Hausfather at Carbon Brief).

Note that the 2σ (95%) range in 2100 is 2° C (± 1° C)… And the model is running a little hot relative to the observations.  The 2016 El Niño should spike toward the top of the 2σ range, not toward the model mean.  I am working on a more detailed post on this and “Gavin’s Twitter Trick,” that I hope to post later this week – So I won’t be responding to comments about the hotness of the models in this thread.

Ross Douthat had an excellent column on this in the New York Times (of all places)…

Neither Hot Nor Cold on Climate

Ross Douthat JUNE 3, 2017

LIKE a lot of conservatives who write about public policy, my views on climate change place me in the ranks of what the British writer Matt Ridley once dubbed the “lukewarmers.”

Lukewarmers accept that the earth is warming and that our civilization’s ample CO2 emissions are a major cause. They doubt, however, that climate change represents a crisis unique among the varied challenges we face, or that the global regulatory schemes advanced to deal with it will work as advertised. And they raise an eyebrow at the contrast between the apocalyptic, absolutist rhetoric with which these schemes are regularly defended and their actual details, which seem mostly designed to enable the globe’s statesmen to greenwash the pursuit of economic and political self-interest.

More specifically, lukewarmers look at the Intergovernmental Panel on Climate Change’s official projections and see a strong likelihood that rising temperatures will drag on G.D.P. without leading to catastrophe. They look at the record of climatological predictions and see a pattern in which observed warming hugs the lower, non-disastrous end of the spectrum of projections. And they look at the substance of the Paris accord, which papered over a failed attempt to set binding emission rules with a set of fine-sounding promises, and see little to justify all the anguish and despair over Donald Trump’s decision to abandon it.


NY Times

Although, I do take issue with is this statement:

Lukewarmers accept that the earth is warming and that our civilization’s ample CO2 emissions are a major cause.

The Earth’s average surface temperature has warmed since the 1600’s and our CO2 emissions have played a role in that warming.  Relative to the total carbon flux, our emissions are hardly “ample” and 20-30% doesn’t strike me as a “major cause.”

And I would also take issue with Mr. Douthat’s answer to his own challenge:

I’ll answer that challenge myself: My own alarm over climate change has gone up modestly since the Obama-era cap-and-trade debates, as the decade or more in which observed warming was slow or even flat — the much-contested warming “pause” — has given way to a clearer rise in global temperatures.

If you chart this spike against the range of climate change projections, it brings the trend up into the middle of climatologists’ scenarios for the first time in some years. Maybe that will be temporary and it will fall back. But the closer the real trend gets to the worst-case projections, the more my lukewarmism will look Pollyannish and require substantial reassessment.

The 2016 El Niño spike didn’t bring “the *trend* up into the middle of climatologists’ scenarios.”  The bottom of the 2σ range is the P97.5 case, 97.5% of the model runs resulted in more warming than P97.5.  The model mean is the P50 case, 50% of the model runs resulted in more warming than P50.  The top of the 2σ range is the P02.5 case, 2.5% of the model runs resulted in more warming than P02.5. A major El Niño spike should spike from P50 toward P02.5, not from P97.5 toward P50.  For a discussion of this nomenclature see The Good, the Bad and the Null Hypothesis.

Lukewarmerism is well-grounded in science and economics.  I suppose it could even be viewed as a climatological version of Pascal’s wager.  Matt Ridley also has an excellent article on Lukewarmerism…


Published on: Tuesday, 20 January, 2015
The polarisation of the climate debate has gone too far

This article appeared in the Times on January 19, 2015:

I am a climate lukewarmer. That means I think recent global warming is real, mostly man-made and will continue but I no longer think it is likely to be dangerous and I think its slow and erratic progress so far is what we should expect in the future. That last year was the warmest yet, in some data sets, but only by a smidgen more than 2005, is precisely in line with such lukewarm thinking.

This view annoys some sceptics who think all climate change is natural or imaginary, but it is even more infuriating to most publicly funded scientists and politicians, who insist climate change is a big risk. My middle-of-the-road position is considered not just wrong, but disgraceful, shameful, verging on scandalous. I am subjected to torrents of online abuse for holding it, very little of it from sceptics.

I was even kept off the shortlist for a part-time, unpaid public-sector appointment in a field unrelated to climate because of having this view, or so the headhunter thought. In the climate debate, paying obeisance to climate scaremongering is about as mandatory for a public appointment, or public funding, as being a Protestant was in 18th-century England.



Marlo Lewis has provided a handy list of the range of opinions that come under the “lukewarmer” label. I subscribe to each of these in some form or to some degree:

“In general, I would describe a ‘lukewarmer’ as someone who:

– Thinks anthropogenic climate change is real but  very far from being a planetary emergency

– Takes due notice of the increasing divergence between climate model predictions and observations and the  growing body of scientific literature challenging IPCC climate sensitivity estimates.

– Regards the usual pastiche of remedies — carbon taxes, cap-and-trade, renewable energy quota, CO2 performance standards – as either an  expensive exercise in futility or a  ‘cure’ worse than the alleged disease (depending how aggressively those policies are implemented).

– Is impressed by — and thankful for — the immense albeit usually unsung benefits of the CO2 fertilization effect on  global agriculture and  green things generally.

– Recognizes that poverty remains the world’s leading cause of  preventable illness and premature death.

– Understands that plentiful, affordable, scalable energy (most of which comes from  CO2-emitting fossil fuels) is essential to poverty eradication and progress towards a  healthier, safer, more prosperous world.”


Update 2:

The main point of my article was to draw attention to how ad-hominem, vicious and personal the attacks on lukewarmers now are from the guardians of the flame of climate alarm. Though I had a huge and overwhelmingly positive response, I could not have wished for a better example of my point than some of the negative reactions to this article. An egregious example was the death threats I received from a Guardian contributor and Greenpeace “translator”, Gary Evans.

On 21 January The Guardian published an article by Dana Nuccitelli, specifically criticizing me. The article was illustrated with a picture of the severed head of a zombie. Beneath the article appeared the following comment from “Bluecloud”:

“Should that not be Ridley’s severed head in the photo?”


The Rational Optimist

Other Lukewarmers like Dr. Pat Michaels, Chip Knappenberger, Dr. Judith Curry, Dr. Roy Spencer and Dr. John Christy are routinely subjected to similar ad hominem attacks from the “guardians of the flame of climate alarm.”


So… If you are a fellow Lukewarmer… What evidence would push you toward alarmism?  What evidence would push you toward rejecting human impacts on the climate as being less than a rounding error? (Note: I view the impacts as only being slightly larger than a rounding error).

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September 25, 2017 6:54 am

There has been no doubt we have been in a warming trend over the past few decades. But before that we were in a cooling trend, and before that we were in a warming trend.
Is there a pattern here?

Reply to  David Middleton
September 25, 2017 8:31 am

At this time usefully accurate forecasts of the coming cooling to about 2650, with about 70 – 75 % probability of success ( according to my own expert opinion) can be made simply by convolving the 1000+/- and 60 year cycles. The establishment scientists and modelers , lukewarmers and the GWPF seem unable to grasp the common sense notion that the earth existed before about 1850 and that unless one knows where the earth is in relation to the longer term cycles – forecasting is futile.
See Figs 1 – 12 at
Here is the Abstract.
The coming cooling: usefully accurate climate forecasting for policy makers.
Dr. Norman J. Page
Email: norpag@att.net
DOI: 10.1177/0958305X16686488
Energy & Environment
0(0) 1–18
(C )The Author(s) 2017
Reprints and permissions:
DOI: 10.1177/0958305X16686488
This paper argues that the methods used by the establishment climate science community are not fit for purpose and that a new forecasting paradigm should be adopted. Earth’s climate is the result of resonances and beats between various quasi-cyclic processes of varying wavelengths. It is not possible to forecast the future unless we have a good understanding of where the earth is in time in relation to the current phases of those different interacting natural quasi periodicities. Evidence is presented specifying the timing and amplitude of the natural 60+/- year and, more importantly, 1,000 year periodicities (observed emergent behaviors) that are so obvious in the temperature record. Data related to the solar climate driver is discussed and the solar cycle 22 low in the neutron count (high solar activity) in 1991 is identified as a solar activity millennial peak and correlated with the millennial peak -inversion point – in the UAH temperature trend in about 2003. The cyclic trends are projected forward and predict a probable general temperature decline in the coming decades and centuries. Estimates of the timing and amplitude of the coming cooling are made. If the real climate outcomes follow a trend which approaches the near term forecasts of this working hypothesis, the divergence between the IPCC forecasts and those projected by this paper will be so large by 2021 as to make the current, supposedly actionable, level of confidence in the IPCC forecasts untenable
Here is Fig 12comment image
Fig. 12 compares the IPCC forecast with the Akasofu (31) forecast (red harmonic) and with the simple and most reasonable working hypothesis of this paper (green line) that the “Golden Spike” temperature peak at about 2003 is the most recent peak in the millennial cycle. Akasofu forecasts a further temperature increase to 2100 to be 0.5°C ± 0.2C, rather than 4.0 C +/- 2.0C predicted by the IPCC. but this interpretation ignores the Millennial inflexion point at 2004. Fig. 12 shows that the well documented 60-year temperature cycle coincidentally also peaks at about 2003.Looking at the shorter 60+/- year wavelength modulation of the millennial trend, the most straightforward hypothesis is that the cooling trends from 2003 forward will simply be a mirror image of the recent rising trends. This is illustrated by the green curve in Fig. 12, which shows cooling until 2038, slight warming to 2073 and then cooling to the end of the century, by which time almost all of the 20th century warming will have been reversed.

richard verney
Reply to  David Middleton
September 25, 2017 9:03 am

I am one of those who accept that the globe has warmed since the LIA, but who has not seen convincing evidence that the globe today is any warmer than it was in the late 1930s/early 1940s, still less that CO2 has had any impact on the warming that has occurred. Indeed, I consider that there are multiple lines of evidence that suggest that the Northern Hemisphere is no warmer today than it was in the late 1930s/early 1940s, notwithstanding that since 1940 some 95% of all manmade CO2 has been emitted.
It is interesting to have a quick look at HADCRUT4 and the warming and the rate of change of warming,viz:
Now according to the IPCC, manmade CO2 emissions only became a significant factor after WW2, and that prior to then, manmade CO2 did not drive temperature rises.
And yet there is no statistical difference in the rate of warming of the warming episodes that took place prior to WW2 when CO2 was not a factor (ie., the 1860 to 1880 warming, and the 1910 to 1940 warming), and the warming episode (late 20th century warming) when CO2 is claimed to be a factor.
Phil Jones (the head of CRU) specifically confirmed that in the BBC interview:

QUESTION: Do you agree that according to the global temperature record used by the IPCC, the rates of global warming from 1860-1880, 1910-1940 and 1975-1998 were identical?
ANSWER:I have also included the trend over the period 1975 to 2009, which has a very similar trend to the period 1975-1998.
So, in answer to the question, the warming rates for all 4 periods are similar and not statistically significantly different from each other.

So it would appear that CO2 emissions post WW2 have not increased the rate of warming.
Further one will note from the plot which only goes up to 2009, that as at 2009, the temperature anomaly was about +0.5 degC (may be +0.52 degC) and that in 1880 it was 0.4degC, 1940 it was +0.4 degC, and in 1943 it was +0.4 degC.
Thus as at around 2009, the temperature anomaly was only around +0.1 degC more than it was in the 1940s, or for that matter only about 0.1 degC above that of 1880. Given the error bounds of this reconstruction, we cannot say that as in 2009, the temperature was any warmer than that seen in 1940 or for that matter in 1880.
Given that CO2 is said to be an issue and driver of temperature change only post WW2, it follows that if CO2 has done anything, it has only increased the temperature by about 0.1degC over and above that seen in the 1940/43. So it would appear that manmade CO2 emissions are not doing much of substance (even if one were to accept that HADCRUT 4 is reasonably accurate).
Of course, I accept that if this plot were to be updated through to 2017, the positive anomaly would be a little higher than the +0.5degC noted in 2009, but that is the result of the recent strong El Nino of 2015/16 and the ENSO cycle has yet to complete with a La Nina.
Presently, the balance of forecasts is for a La Nina late 2017/early 2018, and if that foercast turns out to be correct, there will be a lag of a few months before it has a significant impact on temperatures. It follows that if there is such a La Nina, we may well be seeing in say April/May 2018, HADCRUT 4 with a positive anomaly around the 0.5degC mark and only some 0.1degC over and above temperatures seen in 1880 and in 1940/43 notwithstanding all that CO2 emitted by man over the intervening years.
It is also interesting to have a look at HADCRUT for the Arctic (70 to 90 degN). Viz:
It will be seen that the Arctic today is not as warm as it was in the 1930s/1940s. In the 24 year period between 1922 to 1946 some 12 years (ie., 50% of the time), there was a positive anomaly of +4 degC (or more), whereas in the recent 24 years between 1992 and 2016, there are only 6 years (ie., 25% of the time) where the temperature anomaly is + 4degC (or more). Indeed, recently the positive anomalies have only scrapped to the +4 deg C level, whereas in the past they were generally higher being +5 degC, + 6degC and even + 7degC. No recent year has reached the + 7 degC anomaly seen in 1937/8
The temperature anomaly series do not withstand rigorous scientific study since they never compare like with like and are a constantly moving and altering feast, with stations coming and going, biases caused by high latitude station drop outs, increasing use of urban stations and drop out of rural stations, increasing use of airport stations (which airports have in any event undergone significant change), change of equipment from low sensitive slow response LIG thermometers in large volume enclosures, to high sensitive rapid response platinum resistance thermometers in small enclosures etc. etc
I suspect that if we were to carry out a point by point remeasurement of the best sited stations (CRN1) in the Northern Hemisphere retrofitted with the same type of LIG thermometers as used in the past, and use the same practice and procedure as used at each station in the past, so that on a point by point basis modern day collected RAW data could be compared directly with historic RAW data collected at that station in the 1930s/1940s with no adjustments whatsoever, we would see that there has been no warming over and above the temperatures observed at the station in the 1930s/1940s. This would tell us a lot since this comparison would cover the period when some 95% of all manmade CO2 emissions have taken place.
Our problem is poor quality data. What we require is good high quality data, and we should only work with high quality data. If not any signal to CO2 will inevitably be lost in the noise.

Reply to  David Middleton
September 25, 2017 9:16 am

The funny is only that this pattern here and elsewhere has already been explained several times and there are still fellow-readers who ask: is there a pattern here? Loss of memory in younger people also seems to be a sign of the times. Or is it over-stimulation via smartphone that you can not remember anything?

Reply to  David Middleton
September 25, 2017 1:03 pm

richard verney, not at all impressed by your hand drawn arrows claiming to be trends. At least download some data and fit some linear trends and show the results or don’t bother.

Reply to  David Middleton
September 25, 2017 1:37 pm

The trends illustrated by Richard Verney, which were the subject of the Phil Jones quote included in his comment, have appeared on WUWT several times. If you can’t be bothered to do some research for yourself, that’s your problem. So if you are not impresses, too bad.

Nick Stokes
Reply to  David Middleton
September 25, 2017 1:55 pm

“It is interesting to have a quick look at HADCRUT4 and the warming and the rate of change of warming,viz:”
This graph seems to go around for ever; it first appeared about 2010. It is not HADCRUT 4. And despite claims we don’t know who made it – the attribution is just to Jo Nova’s web site. And it disguises the fact that the warming since 1975, which is really a continuation of the earlier warming, has continued for a lot longer, and to much greater heights than shown. And shows no sign of stopping.

Reply to  David Middleton
September 25, 2017 3:28 pm

“richard verney September 25, 2017 at 9:03 am

The temperature anomaly series do not withstand rigorous scientific study since they never compare like with like and are a constantly moving and altering feast, with stations coming and going, biases caused by high latitude station drop outs, increasing use of urban stations and drop out of rural stations, increasing use of airport stations (which airports have in any event undergone significant change), change of equipment from low sensitive slow response LIG thermometers in large volume enclosures, to high sensitive rapid response platinum resistance thermometers in small enclosures etc. etc

Our problem is poor quality data. What we require is good high quality data, and we should only work with high quality data. If not any signal to CO2 will inevitably be lost in the noise.”


Reply to  David Middleton
September 25, 2017 6:38 pm

earth existed before about 1850
that is an article of faith. there is no test that can be used to prove that.

Reply to  David Middleton
September 26, 2017 9:08 am

There’s an old philosophical question.
How would you prove that God didn’t create the universe 1 second ago, with everything in place and everyone having full memories of their lives up to that point already in place.

Reply to  rbabcock
September 25, 2017 11:56 am

We’ve not been in a warming trend for decades. We were in a warm cycle from the PDO flip of 1977 to the El Nino of 1999, but global average temperature has been flat since then, or cooling, except for the El Nino of 2016.
Before that, as you note, we were in a cool cycle from the 1940s to 1977, and before that in a warm cycle. We’re recovering from the Little Ice Age Cold Period, which followed the Medieval Warm Period, which followed the Dark Ages CP, which followed the Roman WP, which followed the Greek Dark Ages CP, which followed the Minoan WP, which followed a CP, which followed the Egyptian WP, which followed a CP, which followed the Holocene Climatic Optimum.
Despite the many pages of the IPCC, there is no actual evidence of a detectable human influence on global climate. Locally, yes. Witness Las Vegas, for instance.

Reply to  Sixto
September 25, 2017 4:41 pm

Climate Guru Hansen said in 1999, that the 1930’s was 0.5C hotter than the year ,1998, and 2016, which makes the 1930’s the hottest years since that time, up to and including today.
That doesn’t show up in the surface temperature charts because they have all been manipulated to show 1998 as hotter than the 1930’s
Any surface temperature chart that does not show the 1930’s to be as hot or hotter than subsequent years (including 2016, which tied 1998 for temperature) means you are looking at a bogus, bastardized surface temperature chart. The Bastardizers are trying to fool you, and they do a pretty good job as even skeptics use these bogus charts to try to make their point.
If the 1930’s doesn’t show hotter than 1998 and 2016, then you are looking at garbage being passed off as science.

Reply to  Sixto
September 25, 2017 4:49 pm

Either that or they pretend that history started during the 70’s.

Reply to  Sixto
September 25, 2017 5:07 pm

Yup, and when the world ceased warming after the 1990s, as Hansen expected or hoped would not be the case, then no problem! Just cook the books.

Reply to  Sixto
September 25, 2017 9:37 pm


We were in a warm cycle from the PDO flip of 1977 to the El Nino of 1999, but global average temperature has been flat since then, or cooling, except for the El Nino of 2016.

All the global temperature data sets, both surface and satellite, show a warming trend between 2000 and 2015: http://www.ysbl.york.ac.uk/~cowtan/applets/trend/trend.html
I can’t find any that show cooling. What’s your source for that claim please?

Reply to  Sixto
September 25, 2017 10:26 pm

that warming rate is well below the IPCC per decade warming rate prediction. This one is Satellite data,
Only .125C per decade.

Reply to  Sixto
September 26, 2017 9:09 am

2015 was the run up to the recent super El Nino.

Reply to  rbabcock
September 25, 2017 9:05 pm

Power of suggestion. I haven’t noticed any difference where I have lived since the early 70s. Still get 9 months of rain and occasional snow. Still get 3 months of hot dry summers. Still grow the same seasonal crops. Still get 4 seasons. Haven’t noticed anything unusual. It’s uneventful if there is warming but no climate change where I am

September 25, 2017 6:57 am

As a lukewarmer (I feel that the climate change is real and that CO2 plays a minor role in it (sensitivity of 0.3 to 0.5C))
The evidence that would push me towards being more concerned would be a solid warming trend that can’t be attributed to any of the known climate cycles.
The evidence that would cause me to abandon my belief that CO2 plays a minor role would be evidence that natural cycles are sufficient to explain all of the warming. (Unfortunately we would need several hundred years of quality data to pull that off.)

Reply to  MarkW
September 25, 2017 12:27 pm

I must be a denier. I have seen no evidence (or even a proper hypothesis) which shows that CO2 has any effect on the global climate.

Reply to  Phillip Bratby
September 25, 2017 12:54 pm

This ^^^^^^^

Reply to  Phillip Bratby
September 25, 2017 4:50 pm

As stated above, the CO2 signal is too small to be discerned in the over all temperature record.
Despite your efforts to believe otherwise, this is not evidence that it is not there.

Reply to  Phillip Bratby
September 25, 2017 7:27 pm

But because it can’t be discerned, your belief that it is there is simply an article of CACA faith, not a scientific conclusion. Fairies and elves can’t be discerned either, but Sir Arthur Conan Doyle believed in them. John Knight, who posts here, believes that earth, plants, day and night were created before the sun, because the Bible tells him so.
OK, now I really am gone.
No hasta luego, porque no estaria un luego. Entonces, vayan ustedes con Dios.

Reply to  Phillip Bratby
September 26, 2017 9:11 am

While I admit that my beliefs can’t be proven from the data, the fact remains that CO2 does convert photons to heat. Both in the lab and the real world.
On the other hand your frequent claims that it can’t exist because the signal is less than the noise in the climate system is equally fatuous.

john harmsworth
Reply to  MarkW
September 25, 2017 12:39 pm

I would say I am pretty close to this view. I think most of the warming we have seen since the 60’s, when I was a kid, has been due to natural causes and probably related to whatever caused the LIA. That period saw a growth of glaciers and very well recorded low temperatures in the Northern Hemisphere at least. This warming has been very good for mankind and slow enough that wildlife has been quite able to adapt. A warmer climate also generally means a wetter climate which combines with higher CO2 to be very beneficial for crops and other plant life. Even the Sahara is greening!
There is no disaster unfolding or imminent!
At this point there is no evidence that CO2 has any substantial effect on planetary temperatures and I see politics and grossly substandard and even phony, contrived science written all over this cause.
The biggest problem I have with climate science is actually the scientific aspects of it. As a long time science buff I am extremely disappointed in what I see as a major corruption of a scientific field by political opportunists like Al Gore and many others, who see in it a means to attack Capitalism.
I see lots of problems with Capitalism myself, but these people seek to tear it down with no clue as to what to put in its place. God knows, Marxism and Socialism and every other ism that has been tried have been murderous failures.
If Capitalism needs to be superseded it has to be a better idea, not recycled garbage disguised as Environmentalism. The Left has run up against a bankruptcy of ideas and clings to this phony crisis only as a path to power-the only thing they still exist for.
What would change my mind?
Honest data that indicates an acceleration of warming which cannot be explained by natural causes. Or, a better physical understanding of oceanic processes that relate to climate. Or, a recognition of the LIA and a coherent explanation of its cause and how that relates to present climate. Or, just some decent science! The work of Michael Mann is especially egregious in its deceptions, but most other work I see in the field is equally as flawed and politically directed, just not always so deliberate and aggressively false. The field is dominated by third rate people who are not just doing bad work but deliberately pedalling garbage science. The dissection and trashing of Mann’s “Hockey Stick” crap by McIntyre and Mickitrick should have been the death of Mann’s career. Instead the cabal of falsifiers was so endemic in the field that they managed to close around him and protect the rottenest apple in the whole rotten barrel. Very disappointing for science and very destructive to the entire world.
When people like Degrasse Tyson come out in support of the mainstream, and then make it obvious they really have no knowledge of the field, they do a great disservice to science. One can only conclude that they would rather protect their media status than show respect for proper science.
This entire fiasco just shows how easily people of weak moral fibre can be bought off.

Reply to  MarkW
September 25, 2017 12:42 pm

What about a solid warming trend that can be attributed to people fudging the raw temperature data?

Reply to  jorgekafkazar
September 26, 2017 3:40 am

Jorge – do you mean like this?
Tony Heller posted this sequence – all “global” surface temperatures – see the cooling of ~1940-1975 disappear?comment image

Reply to  MarkW
September 26, 2017 8:36 am

The evidence that would push me towards
we have long term paleo records of CO2 and temperature going back at least 600k years. they all show the same thing. When CO2 is high, temperatures drop. When CO2 is low, temperatures rise.
this evidence show that if anything, GHG sensitivity to CO2 is NEGATIVE. It does not in any way support the notion that CO2 sensitivity is > 0.

September 25, 2017 6:59 am

I am a lukewarmer, but now trending away from the alarmist side to the ho hum side. I cannot get excited about warming as small as 1.5C and possibly 0.7C. Ho hum…
Nothing short of a persistent (log) rise in satellite and balloon temperatures to follow CO2 rise would impress me. The ground and ocean temperature sets are worthless imo. I have zero trust in adjusted and homoginized data.

Reply to  sailboarder
September 25, 2017 11:43 am


September 25, 2017 7:09 am

Heh. German political scientists Walter Hallstein and Richard Löwenthal coined a term for it. Finlandization. Art of bowing to the East without mooning the West during the cold war.

September 25, 2017 7:10 am

Once again, those involved in the argument over CO2 emissions all seem the think “no change” will occur without our errecting windmills, solar panels, etc, when, in fact, simple economics is forcing
far more significant emission reductions than anything that the trillions spent so far have accomplished.
These people seem to be just about the only people on the planet who haven’t noticed the obvious
transition from gas to electric power going on in the transportation sector, a huge potential change in emissions as soon as the grid reduces same. How extensive is this transformation? Well, several automakers will no longer build gas-only vehicles after he next few years, some (BMW,
Mercedes-Benz, Volvo) will build an eletric version of every car they sell, etc. I count well over 40 electric models coming to dealer showrooms over the next several years.
Less well known are the revolutionary advances in nuclear power, mostly by the adbent of practical molten salt reactors, which cost a fraction of the money and time to build and operate compared to the typical LWR reactors, and which are as safe as anyone could possibly wish.

Tom Judd
Reply to  arthur4563
September 25, 2017 8:09 am

Building the electric vehicles and selling them are two different things. Thus far the only thing driving (excuse the pun) electric vehicles is the fairly overt threat of compulsion and the only things enabling their sales are substantial tax rebates and carbon credits. When the dismal resale value of these highly limited and pricey vehicles becomes more well known the sales aspect will become that much harder.

Reply to  Tom Judd
September 25, 2017 12:45 pm

‘When the dismal resale value of these highly limited and pricey vehicles becomes more well known…”
Hmm. First I’ve heard of this. Got some data you can share with us? How bad is it?

I Came I Saw I Left
Reply to  arthur4563
September 25, 2017 11:16 am

When you say “will build an electric version of every car they sell” what that translates into is mostly hybrids, which is essentially trendy and irrelevant. They are still ICEs. I looked at a gas-only car today that gets over 40 mpg hwy. Hybrids get what – 50 mpg? That 10 extra mpg is not worth the extra cost of a hybrid that will incur the additional cost of replacing the engine every 100,000 miles, or so (if not sooner), because of battery replacement .

Reply to  I Came I Saw I Left
September 25, 2017 1:33 pm


Reply to  I Came I Saw I Left
September 25, 2017 4:51 pm

I drive an ICE that gets better than 50mpg highway.

john harmsworth
Reply to  arthur4563
September 25, 2017 12:43 pm

What a load of hot air!

george e. smith
Reply to  arthur4563
September 25, 2017 3:38 pm

So where do we have one of these molten salt reactors supplying major league grid power on a 24/7/365 basis ??
I’m not aware of any of them operating in California, let alone enough of them to influence our energy supply.

Reply to  arthur4563
September 26, 2017 8:45 am

transition from gas to electric power
the power grid cannot support anything more than a few percent electric vehicles. we will need to increase the power grid by close to a factor of 10 to allow all electric vehicles. this will take a huge scientific breakthrough or it will simply not happen due to costs.
most people are not aware that the electricity used by a house is about 1 gallon of gasoline equivalent per day. even if we doubled energy production, you cannot move a car very far on 1 gallon of gasoline per day per household. now factor in truck traffic, and what is required to keep a modern economy moving.

September 25, 2017 7:11 am

Climate 101.
The accepted global temperature record is a complete fiction which even if it were true, may have limited relevance. CO2 is not the main driver of the greenhouse effect, water vapour is. There are enormous holes in the knowledge of the climate and models yet Ridley et al will argue about climate sensitivity to 2 decimal places.
Lukewarmers like the GWPF are a fifth column that make real opposition look ridiculous. They do a LOT more harm than good. They look like a valid opposition but they aren’t, they’re enablers of loony alarmism who give them credibility they don’t deserve.
Freeman Dyson thinks climate forecasts are absurd.

john harmsworth
Reply to  David Middleton
September 25, 2017 12:46 pm

With a few billion more spent on this non-science, they could probably adjust that last decimal place by one number! Meanwhile the actual world make utter nonsense of their work. (But they’ll still get paid)

Reply to  paisleyhistory
September 25, 2017 8:42 am

paisleyhistory…you wrote: “Lukewarmers like the GWPF are a fifth column that make real opposition look ridiculous. They do a LOT more harm than good. They look like a valid opposition but they aren’t, they’re enablers of loony alarmism who give them credibility they don’t deserve.”
I am not sure how being opposed to ‘loony alarmism’ enables ‘loony alarmism’. But this is not about enabling or disabling anyone. ‘Lukewarmism’ is the only stance on climate that actually comes directly from the science of climate. To assert that the CO2 concentration has no impact on atmospheric temperature does not adhere to the science. To assert that doubling the CO2 concentration from pre-industrial levels will create a climate crisis, does not adhere to the science either.
I believe my stand is close to Mr. Middleton’s: increasing CO2 is having an impact, but it is certainly smaller than natural variability and may be too small to ever be discernable. I also believe that the current warming, no matter the reason, is a wonderful thing for the majority of the living world, with perhaps a bit of an inconvenience for humans living at or below sea level if it continous (which I give just a 40% chance). The world should be rejoicing that we are returning much needed CO2 to the atmosphere.
Nothing in my stance enables the catastrophists. I am getting the impression that you believe that admitting that CO2 has some impact, is enabling them, but I believe that arguing that CO2 has NO impact, is far more enabling. The warmists may not care about the science, and may only be interested in their agenda, but it is the science that will ultimately undermine their evil plan, not directly attacking their evil plan.

Reply to  jclarke341
September 25, 2017 1:17 pm

With respect is your position a bit of a cop-out? You say:
‘increasing CO2 is having an impact, but it is certainly smaller than natural variability and may be too small to ever be discernable.’
This is the climate equivalent of having your cake and eating it. If any CO2-caused ‘warming’ really is too small to ever be discernable’ surely that’s acknowledgement that you can’t discern any – and by definition there’s zero threat from warming so small is can’t be discerned?

Jean Paul Zodeaux
Reply to  jclarke341
September 25, 2017 8:36 pm

“This is the climate equivalent of having your cake and eating it.”
Eating your cake and having it too. Claiming that something is both indiscernible and discernible is the equivalent of eating your cake and having it too. Having a cake and eating it too is standard practice with cakes, just not so common in its idiomatic usage. The notion that I can’t have my cake and eat it too is absurd and meaningless. What is reflective of the real world is that I cannot eat my cake and have it to. That’s just the way the world works.

Reply to  paisleyhistory
September 25, 2017 8:43 am

Here is an exchange with Dyson
E-mail 4/7/15
Dr Norman Page
Professor Dyson
Saw your Vancouver Sun interview.
I agree that CO2 is beneficial. This will be even more so in future because it is more likely than not that the earth has already entered a long term cooling trend following the recent temperature peak in the quasi-millennial solar driven periodicity .
The climate models on which the entire Catastrophic Global Warming delusion rests are built without regard to the natural 60 and more importantly 1000 year periodicities so obvious in the temperature record. The modelers approach is simply a scientific disaster and lacks even average commonsense .It is exactly like taking the temperature trend from say Feb – July and projecting it ahead linearly for 20 years or so. They back tune their models for less than 100 years when the relevant time scale is millennial. This is scientific malfeasance on a grand scale. The temperature projections of the IPCC – UK Met office models and all the impact studies which derive from them have no solid foundation in empirical science being derived from inherently useless and specifically structurally flawed models. They provide no basis for the discussion of future climate trends and represent an enormous waste of time and money. As a foundation for Governmental climate and energy policy their forecasts are already seen to be grossly in error and are therefore worse than useless. A new forecasting paradigm needs to be adopted. For forecasts of the timing and extent of the coming cooling based on the natural solar activity cycles – most importantly the millennial cycle – and using the neutron count and 10Be record as the most useful proxy for solar activity check my blog-post at http://climatesense-norpag.blogspot.com/2014/07/climate-forecasting-methods-and-cooling.html
The most important factor in climate forecasting is where earth is in regard to the quasi- millennial natural solar activity cycle which has a period in the 960 – 1020 year range. For evidence of this cycle see Figs 5-9. From Fig 9 it is obvious that the earth is just approaching ,just at or just past a peak in the millennial cycle. I suggest that more likely than not the general trends from 1000- 2000 seen in Fig 9 will likely generally repeat from 2000-3000 with the depths of the next LIA at about 2650. The best proxy for solar activity is the neutron monitor count and 10 Be data. My view ,based on the Oulu neutron count – Fig 14 is that the solar activity millennial maximum peaked in Cycle 22 in about 1991. There is a varying lag between the change in the in solar activity and the change in the different temperature metrics. There is a 12 year delay between the activity peak and the probable millennial cyclic temperature peak seen in the RSS data in 2003. http://www.woodfortrees.org/plot/rss/from:1980.1/plot/rss/from:1980.1/to:2003.6/trend/plot/rss/from:2003.6/trend
There has been a cooling temperature trend since then (Usually interpreted as a “pause”) There is likely to be a steepening of the cooling trend in 2017- 2018 corresponding to the very important Ap index break below all recent base values in 2005-6. Fig 13.
The Polar excursions of the last few winters in North America are harbingers of even more extreme winters to come more frequently in the near future.
I would be very happy to discuss this with you by E-mail or phone .It is important that you use your position and visibility to influence United States government policy and also change the perceptions of the MSM and U.S public in this matter. If my forecast cooling actually occurs the policy of CO2 emission reduction will add to the increasing stress on global food production caused by a cooling and generally more arid climate.
Best Regards
Norman Page
E-Mail 4/9/15
Dear Norman Page,
Thank you for your message and for the blog. That all makes sense.
I wish I knew how to get important people to listen to you. But there is
not much that I can do. I have zero credibility as an expert on climate.
I am just a theoretical physicist, 91 years old and obviously out of touch
with the real world. I do what I can, writing reviews and giving talks,
but important people are not listening to me. They will listen when the
glaciers start growing in Kentucky, but I will not be around then. With
all good wishes, yours ever, Freeman Dyson.
Email 4/9/15
Professor Dyson Would you have any objection to my posting our email exchange on my blog?
> Best Regards Norman Page
E-Mail 4/9/15
Yes, you are welcome to post this exchange any way you like. Thank you
for asking. Yours, Freeman Dyson.

Reply to  Dr Norman Page
September 26, 2017 6:54 am

Thank you for posting this exchange Dr. Page.
Dr. Dyson is a gentleman for whom who I have the greatest respect.
At the risk of disagreeing with him, he is not “just a theoretical physicist”, albeit he is “91 years old” and is certainly not “out of touch with the real world”.”
He is a man of great intellect and integrity who speaks the truth for the benefit of all humanity, despite the risks of doing so in this toxic environment of global warming extremism.

Ron Long
September 25, 2017 7:12 am

The position of a geologist (I believe, from registered comments herein and my own interaction with fellow geologists, especially those familiar with sequence stratigraphy) is that the variation observed to date does not come anywhere near to exceeding the natural variation, ie, there is no actual signal detectable against the nosiey background. Whether or not there is some anthropogenic effect is not discernable, but if there is it is so small that it is irrelevant. Lukewarm then becomesa term of no scientific utility. Please do not take any of my comment as an endorsement of pollution.

Jimmy Haigh
Reply to  Ron Long
September 25, 2017 7:26 am

As a geologist familiar with sequence stratigraphy I wholeheartedly agree.

John F. Hultquist
Reply to  David Middleton
September 25, 2017 8:08 am

You need a fourth:
4) Radiatively active gases such as water vapor and carbon dioxide do play a role in air temperature but the CO2 increase is of negligible impact so human impact by this manner is also negligible.

Ron Long
Reply to  David Middleton
September 25, 2017 8:08 am

David, while I find you to be a rational geologist I think the statement of “three major categories:” is an opinion. The question is this: What is the net effect of anthropogenic CO2 in the atmosphere, considering forcings and feedbacks? Neither you nor any other scientist can answer this as the total earth environment is so complex it is essentially chaotic. So we are left to look at useful, repetitive, signals, and these are shown to us by sequence stratigraphy. This says nothing anthropogenic is detectable in the total earth environment.

Reply to  David Middleton
September 25, 2017 8:28 am

“So, we are responsible for at least some of the warming over the past 150 years.”
The real question is, is that “some” either discernable or measureable?

Reply to  David Middleton
September 25, 2017 9:39 am

I would say that the impact of CO2 won’t be discernible until we have a much, much greater handle on the many natural variabilities.
With a couple hundred years of good quality data, we may be able to get a good enough handle on the size and timing of the various natural cycles that we will be able to tease out the CO2 signal from the mess.

Clyde Spencer
Reply to  David Middleton
September 25, 2017 11:01 am

You said, “Maybe I need to devise a numerical scale.” Make sure it is logarithmic, like the Richter Scale.

Reply to  David Middleton
September 25, 2017 11:20 am

True Mark. And add to that that we are still not, to this day, collecting ‘good quality data’. At least I assume our climate data isn’t good quality, since they keep needing to adjust it.
Which brings me to what it would take for me to turn from Lukewarmer to alarmed. The Alarmists would need to go 6 full years without needing to adjust the temperature record.

Reply to  David Middleton
September 25, 2017 12:08 pm

The effect of increased CO2 in the atmosphere is not as in models, which imply highly positive feedbacks. But most likely, in the actual, complex climate system, net feedbacks are negative, so the GHE of more CO2 is negligible at best.
Rather than lying in IPCC’s range of 1.5 to 4.5 degrees C per doubling of CO2, the actual figure, in so far as ECS exists at all, is 0.0 to 2.0 degrees C, ie net negative to very slightly positive, from the lab value of 1.2 degrees C.

Reply to  David Middleton
September 25, 2017 12:52 pm

Your assessment then would imply a range something like 0.0 to 1.5 degrees C, with the possibility of even a cooling effect, ie -0.5 to 1.5 degrees C. I’d second that estimate.

Reply to  David Middleton
September 25, 2017 1:04 pm

While a narrow range, I’d zero in on that, too.
IMO it only stands to reason that net feedback effects should be at least slightly negative. The models ignore or downplay the negative feedback effects of water vapor, eg evaporative cooling and possibly clouds, while concentrating on its radiative effect.
I’m not sure that increased water vapor is even in evidence as a result of more CO2. Nor is man-made warming from the GHE evident at the one place it ought to be seen most starkly, ie the South Pole. No warming there at all in a good, long record.

john harmsworth
Reply to  David Middleton
September 25, 2017 1:41 pm

The heat loss from the planet during a typical nightside utterly dwarfs any CO2 effect. That only leaves daytime as a potential warming factor via heat retention due to CO2.
There are almost no trends recognizable in daytime highs anywhere in the world, so that effect is not visible. The only place where daytime highs might be setting records with any frequency is in the Arctic. Since we have very poor records of this area it is difficult to say. Also, Arctic temperatures are greatly effected by the ice condition, varying from a marine climate to the cold, dry desert that comes when the ice is at maximum extent.
At present we have low ice extent and the warmer, marine climate prevails North of 60.
The ocean temperatures have been reduced by the cooling effect of the open water and now the ice is growing again.
This will lead to a maximum ice extent and much colder Arctic temperatures.
As the Arctic region is responsible for much of the observed warming of the period from 1980 to 2000, and that has come to an end, we now have 18 years of no atmospheric temperature increase.
The next phase is maximum ice extent and lower temperatures in the North, which will translate into lower temperatures worldwide.
This is the nature of the 60+ year cycle. The pseudo-scientists who inhabit the climate mainstream could have found this if they were actually looking for cause and effect. They decided on a cause before they pretended to look. They continue to feast off pretending to look.
I consider many of them to be criminals.

Reply to  David Middleton
September 25, 2017 4:56 pm

You need to include a “No evidence of a net gain in heat in the Earth’s atmosphere via CO2” catagory.
That’s better than total rejection (because their is no evidence it might not happen in the future), and it is a little more skeptical than the Lukewarmer position, which assumes some warming (without evidence).
I’m a “Show me the Money” kind of skeptic.
You wouldn’t think that would be hard to do for the 97% who push CAGW. But to date, no evidence, one way or the other.
We don’t know what CO2 is actually doing to the atmosphere, and anyone who says they do, are wrong.

Reply to  David Middleton
September 25, 2017 9:17 pm

David Middleton
Do you have a proof that humans are responsible for at least half of the rise from 280-400 ppm CO2 ?
At least half of the rise from 280-400 ppm CO2 would mean humans are responsible for major portion of the increase in CO2 during the last 150 years.
You qualify for the third category instead of second category !
3.Blind embrace of the CAGW religion.

Reply to  David Middleton
September 26, 2017 2:56 am

What is absent is the evidence that CO2 drives global temperature. It was clearly warmer in earlier periods in history before the rascals adjusted it away.
James Lovelock following Climategate
“If you look back on climate history it sometimes took anything up to 1,000 years before a change in one of the variables kicked in and had an effect. And during those 1,000 years the temperature could have gone in the other direction to what you thought it should have done. What right have the scientists with their models to say that in 2100 the temperature will have risen by 5C?”

Reply to  David Middleton
September 26, 2017 9:49 am

David Middleton wrote: “I tend to think that the true TCR is 0.5-1.0 C”
Thank you David – I tend to think climate sensitivity to CO2 (“ECS”) is between 0C and 0.5C. I dislike the term “luke-warmist” because it contains the odious term “warmist”. 🙂
From a political standpoint, our positions are similar – IF humankind is causing some global warming, it is NOT catastrophic (and is probably beneficial, imo).
Furthermore, increases in atmospheric CO2, whatever the cause, are clearly beneficial to humanity and the environment. CO2 is not alarmingly high in the atmosphere, it is alarmingly low – for the continued survival of terrestrial carbon-based life on Earth.
BUT from a scientific standpoint I have some concerns:
I proved in January 2008 (published on icecap.us) that CO2 lags temperature at all measured time scales, from ~~300 to 800 years in the ice core record to ~9 months in the modern data record, on a shorter time cycle. The proof is that dCO2/dt changes ~contemporaneously with global temperature, and its integral atmospheric CO2 lags temperature by about 9 months. Here is an approximation: http://www.woodfortrees.org/plot/esrl-co2/from:1979/mean:12/derivative/plot/uah5/from:1979/scale:0.22/offset:0.14
If ECS was significant, CO2 would not lag temperature at all measured time scales and this close relationship would not be apparent in the data record.
My conclusion does NOT mean that current temperature change is the only or even the primary driver of increasing CO2 – other major drivers of increasing CO2 could include fossil fuel combustion, deforestation, deep ocean exsolution of CO2, etc.
Humlum et al published a conclusion similar to mine in 2013, but the climate science community is only now starting to openly discuss this subject – I think it is important, far too important to be ignored.
Best regards, Allan

Jim Ross
Reply to  David Middleton
September 26, 2017 12:24 pm

You say “The change in the 13C ratio is consistent with the volume of CO2 that humans have released from geologic sequestration.” Consistent with (in terms of direction of change,which is the usual argument, not “volume”)… then yes, atmospheric 13C ratio is going down and this is “consistent with” the incremental CO2 having a 13C ratio lower than the current atmospheric value. Is that what you are saying? if so, no dispute. If you want to say that the decline in 13C RATIO is aligned with what we would expect if it was caused by burning fossil fuels alone then I have to disagree. Not only do the data tell us clearly that the 13C ratio of the incremental CO2 is -13 per mil (as opposed to fossil fuels at -26 to -28 per mil), the latest Keeling paper (discussed here quite recently) actually recognises that the models do not match the data.
The discussion of the latest Keeling paper is here:https://wattsupwiththat.com/2017/09/12/study-plants-are-globally-getting-more-efficient-thanks-to-rising-carbon-dioxide/

Jim Ross
Reply to  David Middleton
September 26, 2017 1:09 pm

Thank you for your prompt response. What you need to look at is a plot of d13C against 1/CO2 (I showed an example on the previous thread). If the incremental CO2 has a constant d13C content (on average), the plot will be a straight line. It is.
A quote from the Keeling et al (2017) paper:
“Using updated records, we show that no plausible combination of sources and sinks of CO2 from fossil, fuel, land, and oceans can explain the observed 13C-Suess effect unless … (insert new, novel, extra- complexity excuse)”. It is incredibly simple to explain the observed decline of atmospheric d13C … it is that the incremental CO2 has, on average, a d13C content of circa -13 per mil. The issue here is explaining WHY it is -13 and not -28. The models used by Keeing et al are not able to explain this any longer because the models are based on assumptions that would lead to a change in d13C content (of the incremental CO2) over time, which does not appear to be happening. They therefore introduce a new variable, previously assumed to be constant, that can be used to ensure a match. Speculation, not science.

Jim Ross
Reply to  David Middleton
September 26, 2017 1:29 pm

Sorry, David, I forgot answer your final question. I am a bit reluctant to stray into areas well beyond my expertise, but I can show evidence that the incremenental CO2 has had a d13C content of circa -13 per mil since 1850 or earlier (but not tonight!). This does not tell us definitively what the source is, but it is interesting that it appears to have been about the same for such a long time (relatively speaking).

Jim Ross
Reply to  David Middleton
September 26, 2017 1:38 pm

David, the ice core data are remarkably consistent. I will post some plots tomorrow, but would greatly appreciate your independent “peer” review. I believe my view on the recent d13C content being -13 per mil is not in itself controversial, but is somewhat “hidden” in the literature and the models used to explain it are (as I noted) are getting more and more complex. I can provide references when I have time.

Jim Ross
Reply to  David Middleton
September 27, 2017 6:51 am

I am sure you are familiar with much of the background, but I can provide more detail if you would like. The data shown below are monthly “seasonally adjusted” from Scripps Institute of Oceanography, which means that the annual cycle has been removed. In the case of the South Pole, this is a very minor adjustment but provides better resolution of the longer term trends. The data source (downloaded on 20170501) is:
First, monthly atmospheric data plotted against time (δ13C data only available since 1977):
Second, δ13C plotted against 1/CO2:
The intercept of the linear trend line (-13.02 per mil) reflects the average content over the time period. If the incremental CO2 had a constant δ13C content it would be a simple linear relationship, but it is not a fixed value over the shorter term because it decreases significantly (becomes more negative) during an El Niño and increases with a La Niña. Still, it does support the view that in the longer term it has been the same value on average. The underlying mathematical basis for the relationship between δ13C and 1/CO2 is sometimes referred to as the Keeling equation, with the graph itself being referred to as the Keeling plot. See here for more details:
I have just noticed that the above reference shows the intercept for the Law Dome ice core data to be -13.1 per mil (see Figure 1) so I hardly need to bother with the next section!
For a more recent version of ice and fern data from Law Dome and South Pole, I used the Supplemental Information from the following paper:
Adding these data to the above plot gives:
The atmospheric data (in blue) are a copy of the previous plot and the trend line for the ice and fern data is based on that data alone, so the two lines are independent of each other. Although these ice and fern data must be subject to greater uncertainty than the atmospheric measurements, the similarity of intercepts is remarkable.
One final plot is one that has been shown on WUWT many times, but I do not recall any references to the choice of scales:
The left scale is linear in δ13C but, to get alignment with the CO2 data, the author has quite rightly used a right-hand scale that is linear in the reciprocal of CO2 which reflects a constant δ13C value for the incremental CO2! Further, we can compute that value simply by comparing the two scales: taking 1/CO2 values of .0035 and .0029 (right scale) and reading off the equivalent δ13C values (outer left scale) of -6.47 and -7.56 respectively gives a constant δ13C value for the incremental CO2 since 1750-1800 of -12.8 per mil. Close enough to -13, I think you’ll agree.
As noted before, the observation that the δ13C of the incremental CO2 is around -13 per mil is not controversial in itself and is an input to the climate models. The following paper illustrates a possible explanation on Figure 5.
Note that the gradient of the black vector is -38/3 (see text below figure), i.e. -12.7 per mil, and the primary adjustment to get to that value requires a major flux of 13C through ocean disequilibrium (difference between δ13C going in and δ13C coming out). Not impossible, but how likely is this multi-variable model to satisfy the consistency of the long term trend seen in the data. Which brings us back to the Keeling et al (2017) paper mentioned in my earlier comment where their complicated model was unable to match the δ13C observations until they invented a new variable.
In summary …
The reasons that I feel uncomfortable with the “settled science” view are (i) that there seems to be a reluctance to openly discuss and explain the facts regarding δ13C and (ii) the models are based on parameters that are almost certainly changing with time (e.g. the δ13C content of fossil fuels) and are getting more and more complicated with additional variables being introduced (as per the Keeling et al paper referenced in my earlier comment), in stark contrast to an apparently very simple and stable relationship shown by the data.

Jim Ross
Reply to  David Middleton
September 28, 2017 2:11 am

A small correction to my comment above that “the δ13C of the incremental CO2 is around -13 per mil is not controversial in itself and is an input to the climate models” is not exactly what I meant to say. Some “static” models (based on an annual balance of CO2 and δ13C) use this fact as an input constraint (e.g. Randerson et al, 2002, referenced above), whereas more complex time-variant models (e.g. Keeling et al, 2017, also referenced above) may generate a δ13C profile as an output … and then find that it does not match the observations.
My main point, however, is that there seems to be a tendency by some settled science proponents to intentionally mask the true facts by using phrases like “consistent with” when the reality is that the data do not actually match what is implied by that statement. Some “lukewarmers” who have not studied a particular aspect in depth may be tricked into thinking such an issue has been “proved”.

September 25, 2017 7:15 am

Not a lukewarmer.
Would lean more towards AGW hypotheses on the date that the Pro-AGW people make their own case, purely by Science, devoid of all influence by talking heads, journalists, communicators, pollsters and the rest of the social riff raff like economists, lawyers and bureaucrats who seek to make a living from the derivatives of other peoples’ Science.
If the Science is good and pure, present the Science with purity, let the scientific process run its usual course of hypothesis testing, then publish only when the work is done so well that proper, formal error estimates put on it allow determination of whether it is significant and can be acted on with a high degree of confidence.
So far we have had endless episodes of Flying Circus Science.
Now let us have the few percent of that Science that might pass those tests be identified and the rest scrapped.
The concept of lukewarmer has no place in good pure Science which is devoidd of emotion and personal belief. Geoff

September 25, 2017 7:18 am

The theory that CO2 warms the atmosphere is unproven because the feedback is unknown. And more than half the instrumental era data show it is false : before the 1950s where data show stable CO2 but increasing temperature and from the 1950s to the 1970s where data show increasing CO2 but there was a global cooling hysteria.
So no, lukewarmism is not well-grounded in science and is not legitimate.

Reply to  Frederic
September 25, 2017 7:34 am

And we do have the real problem of “adjusted” surface temperature claims. There is so much infill, done by a non-blind process, that the expectations of the researcher have a free run. This situation is like N-rays or counting human chromosomes at best.

Steve Case
Reply to  Tom Halla
September 25, 2017 7:56 am

In the what we know, don’t know and know we don’t know departments, feed backs and “Corrections” are big players. Are feed backs positive or negative? Are the “Corrections” legitimate or subject to bias?
The corrections obviously follow a pattern that would suggest bias. That we know. Too many people think they are legitimate.
We should know that we don’t know the sign of feed backs. Too many people think they know it’s positive.

Gunga Din
Reply to  Tom Halla
September 25, 2017 1:48 pm

There is no “control” for the experiment required to just what Man’s CO2 is doing to the planet.
The closest we had was the past temperature records which Hansen has fiddled with.
Call up current records of past temperatures online if you want but they are not what they used to be.

Reply to  David Middleton
September 25, 2017 8:29 am

I would describe myself as a lukewarmer, as in Matt Ridley’s description.
And agree that natural variability has a larger impact than the human component, even (or especially) in the Arctic, where the amount of sea ice loss has happened MUCH FASTER than predicted.
Arctic species have had to adjust to much larger and faster changes than have occurred to date (or predicted for the near future) and they would not have survived as species if they had not had the capability to successfully adapt.
Susan Crockford, zoologist

richard verney
Reply to  David Middleton
September 25, 2017 9:29 am

That’s simply a function of natural variability being far larger than the human impact.

This is a logical fail.
If natural variation is larger than human impact, it is impossible to determine whether there is any human impact at all.
I have often made the point that Climate Sensitivity to CO2 can only be determined by actual observation of Earth’s atmosphere and empirical data obtained therefrom, and we will never be able to extract the signal to CO2 (if any at all) until such time as we know and understand everything there is to know and understand about natural variation, its constituent components, and the upper and lower bounds of each and every one of the constituent components of natural variation. It is only then that we will be in a position to eek out the signal from the noise of natural variability.
The real problem we face is the poor quality of our data sets, and the problem caused by scientists not wanting to collect and use high quality data, but rather to seek to make do with poor quality data and making adjustments thereto with the hope that a silk purse can be made from a sow’s ear. This approach will not work as the error bars/uncertainties are too great.
I think that we can, at this stage, say something about Climate Sensitivity, and that is if our data sets are good with low error bars since it is not possible to extract the signal to CO2 from these data sets, Climate Sensitivity to CO2 (if any at all) must be small. If on the other hand our data sets are poor with wide error margins, then the possibility exists that Climate Sensitivity to CO2 (if any at all) could be as large as the error bounds of our data sets.

Reply to  David Middleton
September 25, 2017 9:44 am

richard, that is not correct. We can detect small signals in the presence of large signals. In engineering we do it all the time. What is needed is a solid knowledge of all the signals in a system.
At present, we do not understand the large (natural) signals sufficiently. As a result, the CO2 signal is smaller than the error bars on the natural signals. This is what makes it undetectable at this time.

richard verney
Reply to  David Middleton
September 25, 2017 12:13 pm

Actually, we would only need to nail down a climate sensitivity value.

How do you nail down climate sensitivity if you cannot observe it, ie., if you cannot eek the signal out from the noise?
What is the reason why no standard text book that lists the properties of CO2, states that one of the properties of CO2 is that per mole of CO2 causes X degC of warming?

richard verney
Reply to  David Middleton
September 25, 2017 12:54 pm

The problem is this.
Have a look at the above plot, and one will note that the temperatures in 1878 to 1879 changed by 1 degC, ie., from an anomaly of -0.6degC to +0.4 degC.
Whilst we do not know how much CO2 increased between 1878 and 1879, our best guestimate would be only a small fraction of a ppm which could not have driven much of a temperature rise. This means that natural variation can be in the order of 1 degC. Indeed, we see this type pf warming with El Nino events, and we have no idea what drives El Nino (but it is not CO2).
Given that natural variability is so large, until we get a proper handle on natural variability we will never be able to identify this event as something other than natural variability.
The signal is completely lost in the noise of natural variability.

Reply to  David Middleton
September 25, 2017 2:44 pm

I didn’t say it would be easy. The radiative forcing bit can be reasonably nailed down. However, in order to translate that into temperature change, there would have to be more than 1,000 years of precise instrumental data.

I’ve done this based on the seasonal cycle. I know how much sun is at toa, and what an atm-less surface would have. And I know how much temps change at that exact same place. We get a defined change in forcing daily, and we have millions of records.
My process only works outside the tropics, and this is a daily change in temp, divide by 24 to get the instantaneous value in Degree F per 1W/m^2
These are by latitude bands for land stations. All of the raw data and code is available in SourceForge

Reply to  David Middleton
September 26, 2017 12:27 am

But do you not see the problem that arises when you think of believe a matter is correct, when there is no way to show it is.
It does not advance the science when you adopt and publicise a stance like lukewarmer based on belief.
There can be no progress about global warming big picture until a way is found to separate natural from anthro. All that can result is backward progress countered by valid rebuttal. Which, for which we thank you, is precisely what you have been doing, thankfully with impact. Geoff

Reply to  Frederic
September 25, 2017 9:41 am

Feedbacks either reduce or amplify the impact of CO2. They can’t negate it altogether.
All of the science to date indicates that the climate is regulated by multiple strong negative feedbacks.

richard verney
Reply to  MarkW
September 25, 2017 12:09 pm

This depends whether you define a feedback as a feedback to CO2, or a feedback to warming.
What is there to prevent a doubling of CO2 causing a warming of 0.3 degrees, and a rise in temperature of 0,3 degrees to create more cloudiness resulting in a reduction of temperature of 0.3 degC such that each effectively cancel the other out, resulting in no net change.
That would mean that in Earth’s system, the climate sensitivity to CO2 would be zero.

Reply to  MarkW
September 25, 2017 1:25 pm

“They can’t negate it altogether.”
Actually, they can, if there is an integrating element in the feedback loop. See “PID control”.

Reply to  MarkW
September 25, 2017 4:57 pm

Richard, there is no such thing as a feedback to CO2, there is only feedback to warming.
If warming caused an increase in cloudiness, which then caused the temperature to drop back to what the temperature was prior to the warming, then the cloudiness would also drop back to what it was.
For there to be an sustained increase in cloudiness in this scenario, there must also be a sustained increase in temperature.

Reply to  MarkW
September 25, 2017 4:59 pm

Forest, if the feedback caused more cooling than the initial warming, then the feedback would disappear since it was caused by the warming in the first place.
For an integrating element to work, you need an external source of energy.

Reply to  MarkW
September 25, 2017 7:05 pm

Another way to put it is that the energy that drives the feedback comes from the signal. The feedback can’t have more energy than the signal that is driving it.

Reply to  MarkW
September 26, 2017 9:38 am

Integration requires only non-dissipation. Nothing is ever totally non-dissipative in this entropy dominated universe, but it can be as close to it as makes no practical difference.

Reply to  MarkW
September 26, 2017 10:12 am

As Richard so accurately points out, and as you acknowledge, warming/cooling effects are not direct feedbacks to CO2. But, just because these aren’t, doesn’t mean that CO2 itself doesn’t have a feedback mechanism. In this case, I suggest that plant life would be the appropriate analogous feedback mechanism to consider. And given that there are different uptake rates (plant growth) from release rates (plant decay) it’s entirely possible (or, at least plausible) that a CO2 feedback could result in a end point (defined simply as the point in time when you took the measurement, since there’s no real ending) lower than your initial start point. I think that’s one of the fundamental aspects of non-linear systems. Even if we take that our climate isn’t perfectly chaotic, in that it seems to be strongly damped and bounded, it’s still non-linear and can surprise us with results that don’t follow from our simplistic linear thought processes.

September 25, 2017 7:20 am

As a lukewarmer myself, I estimate human contribution to global warming as about one third, based on comparisons of the effects of last warming push (1975-2003) to previous ones. This assumes natural warming has continued at the same rate. As we cannot estimate natural variability during this time, we don’t know if it is a little more or a little less.
I would become alarmed if the rates of change increased significantly over the next couple of decades. I would think I might be wrong if the rates of change don’t decrease over the next couple of decades compared to the 1975-2003 period.
Nothing will make me think that human emissions don’t have an effect on climate, since the evidence for that already has been produced.
This is my view of future temperatures by 2025:
If I am way off then I don’t understand it. If I am spot on it could still be luck.

D. J. Hawkins
Reply to  David Middleton
September 25, 2017 8:04 am

As King Charlemagne sings in Pippin:
“It’s smarter to be lucky
Than it’s lucky to be smart.”

Clyde Spencer
Reply to  David Middleton
September 25, 2017 11:04 am

Napoleon would have considered you a good candidate for promotion.

Reply to  David Middleton
September 25, 2017 9:55 am

It’s Ed Hawkins’. I just update it.

Reply to  Javier
September 25, 2017 8:23 am

Javier, in 2025 we will be on CMIP11 and HadCRUT9 so you will need to adjust your “Observations” line down some pre 2015 and up post 2015.

Bill Illis
Reply to  Javier
September 25, 2017 8:31 am

Those CMIP5 RCP4.5 numbers are NOT accurate with respect to the 1961-1990 mean.
The 2016 RCP4.5 average, for example, is +0.85C in the 1961-1990 base period.
In fact, even the Hadcrut4 numbers are not right with respect to the 1961-1990 base period.
That is the issue with so many of these graphs from the warmists. They mix up base periods to show an inaccurate but appealing to their audience view.
These are the accurate numbers for RCP4.5 with respect to 1961-1990.
Hadcrut4 here.

Reply to  Bill Illis
September 25, 2017 10:39 am

I’ll check that, thanks.

Reply to  Bill Illis
September 25, 2017 2:52 pm

Hi Bill,
I checked the data and you are correct. Ed Hawkins figure is wrong. The CMIP data has a different baseline, and in the figure it is compressed, looking more similar to the observations than it really is. I will make a new figure with the correct data.
From now on I won’t trust Ed Hawkins.

Reply to  David Middleton
September 25, 2017 3:58 pm

Maybe, but the mistakes always go in the same direction. If they make a mistake in the opposite direction they quickly realize.
I’ll try to have a correct figure by tomorrow, here, with the climate explorer data, in case you want to use it.

Reply to  David Middleton
September 25, 2017 5:01 pm

No problem. Actually it was less work than I thought. Here you have:comment image
It is obvious that the models, even with RCP4.5, believe we are stuck in a permanent very strong El Niño that is getting worse with time. I guess that’s what the people that programmed the models thought was going to happen.

Reply to  Bill Illis
September 25, 2017 5:19 pm

Bill Illis,
Thank you for stressing this large incompatibility of graphs showing differences between CMIP and observed.
Steve McIntyre did several pieces on this on Climate Audit. Nic Lewis also.
One piece is at https://climateaudit.org/2016/04/19/gavin-schmidt-and-reference-period-trickery/
The other matter with large uncertainty is the observed temperatures after about 2000. Graphs showing temperatures using the Karl adjustments have different conclusions to others, such as satellite temperatures. Only one can be correct. Which is it? We should not tolerate loose science where pro AGW people look at Karlised and sceptics look at AUH, then go their separate ways with opinions. One will be wrong.

Reply to  Javier
September 25, 2017 8:40 am

I’ll be convinced the globe is warming when it unequivocally gets warmer than the Eemian(last interglacial. At best the ice core records show that the current interglacial isn’t cooling as fast as the Eemian did.

Bob Weber
Reply to  Javier
September 25, 2017 9:34 am

Try not to take this personally. Lukewarmism is applied both ways: for the cause and the effects – leaving the public mystified. All climate change is 100% natural.
>> Mankind has no large scale enduring influence on temperatures. None. <<
"Lukewarmism' is bad word usage leaving too many unanswered questions swept under the rug for the sake of conformity. Lukewarmism is going along with absolutely phony science – it is a 'go along' consensus groupthink construct. It is warmism-lite; lukewarmists utilize the same groupthink herding/blocking tactics as the warmists.
Lukewarmists will eventually be identified by the public as wrong wrt the human-caused climate connection, as it is now a matter of peer-reviewed science that solar activity causes warming and cooling, and that the sun caused the 20th century warming, the post 1976 warming, and the 2015-2016 ENSO.
CO2 does not control temperatures, it’s the other way around.
Contrary to AGW theory, rising CO2 did not warm the ocean or land during the 30 years of cooling after 1945. Lukewarmists have the same intractable problem as warmists in using manmade CO2 emission theology to explain the three different rates of warming under increasing CO2 over decadal scales.
The sun alone causes warming, cooling, and extreme events, not CO2!
So Matt Ridley – lukewarmism is wrong on causation. All climate change is natural. 100% natural.
CO2 warmism has technically already bit the dust so why do skeptics keep it alive?
Were the recent hurricanes 33% manmade too?

Reply to  Bob Weber
September 25, 2017 9:48 am

Lukewarmists do not claim that CO2 controls the climate. That’s the alarmist position.
Lukewarmists acknowledge that CO2 has an impact on climate, but it is one of many such influences and far from the most important one.

Bob Weber
Reply to  Bob Weber
September 25, 2017 9:55 am

“Lukewarmists do not claim that CO2 controls the climate. That’s the alarmist position.”
When someone claims to be a lukewarmist and assigns 33% of warming to mankind, then it is clear lukewarmers DO attribute CO2 as a temperature controller, albeit not 100% but still a major controller of temps and therefore of climate.
See the duplicity?

richard verney
Reply to  Bob Weber
September 25, 2017 1:07 pm

The warming since 1850 has only been in the neighborhood of 1 C</blockquote.
Have a look at the (old) HADCRUT4 plot. Apart from the recent strong El Nino (2015/16), temperatures are only about 0.1 degC above that observed in 1880! ie., around an anomaly of +0.5degc compared to the 1880 anomaly of + 0.4degC.
If the current forecasts for a La Nina at the end of this year/early 2018 are correct and a La Nina develops, then by April/May 2018, it is likely that we will see that current temperature anomalies will again be only about 0.1degc above those observed in 1880!

Reply to  Bob Weber
September 25, 2017 5:01 pm

cool, there is no duplicity, just you trying to pull a fast one with the labels.

Reply to  Javier
September 25, 2017 9:48 am

Except for the fact that what you have graphed as “observed” bares little resemblance to reality.
Who knows where that maladjusted sequence of non-data will end up !!

Reply to  Javier
September 25, 2017 12:15 pm

HadCRU is a pack of lies.
There is no actual evidence that human activities, which both warm and cool, have had any measurable effect on global average temperature or any other planetwide climatic phenomenon, with the possible exception of cleaning the air since the ’70s, which China and India are now dirtying again.
Urbanization, irrigation and other human activities have affected localities and regions, but these activities haven’t yet added up to a detectable global effect, in part because what we do cuts both ways. We can’t even know the sign of any net human effect.

Reply to  Sixto
September 25, 2017 1:18 pm

Sixto, you are welcome to believe whatever you want. I have researched the issue with the same care I put on past climatology, reading hundreds of scientific articles on the issue, and checking the data. I am convinced that the effect of human emissions on climate is clear, but it is not overriding natural variability.

john harmsworth
Reply to  Sixto
September 25, 2017 2:29 pm

I agree with Sixto on this basis:
Evidence does not exist to show warming caused by humans
The warming we have seen is not outside past natural variance limits
No indication that this recent warming trend, which stopped around 2000, isn’t already over.
No reason to think it is not just a continuation of the trend out of the LIA
No explanation for the LIA, just persistent attempts to cover it up, which is not science ( certainly no indication that CO2 or lack thereof,had anything to do with it)

Reply to  Sixto
September 25, 2017 4:37 pm

Please state the evidence that you have found for a human fingerprint on global climate since c. AD 1950, or whatever point at which you think our influence became detectable.
It doesn’t matter how many pages IPCC reports have or how many papers you’ve read. I have yet to find convincing evidence for the alleged human fingerprint. I’ve been looking since the 1980s and still haven’t found it. Maybe I haven’t read the papers which you have, so I’d appreciate knowing what has convinced you that a human influence is detectable.

Reply to  Sixto
September 25, 2017 5:10 pm

How do you separate and increase in radiative forcing from more H2O in a warmer world from a possible effect of man-made GHGs?
How do you show that whatever manmade warming there might be isn’t from cleaner air rather than more CO2?
I repeat. There is no dispositive evidence whatsoever that man-made CO2 has had any measurable effect on “climate”. How then to justify dismantling industrial civilization?

Reply to  Sixto
September 25, 2017 5:11 pm

“I am convinced that the effect of human emissions on climate is clear,”
Would you mind pointing out to me how you reach this conclusion?

Reply to  Sixto
September 25, 2017 5:39 pm

It is hard to write in a comment what has been distilled from scores of articles and data, and at the same time be convincing to people that don’t want to be convinced. Anthropogenic warming is somehow of a different nature than natural warming. It essentially affects minimum temperatures more than maximum temperatures. It seems to affect night temperatures more than day temperatures. It appears to affect winter temperatures more than summer temperatures. It appears to decrease the rate of cooling more than increase the rate of warming. It appears to be more global while natural change is more regional.
And the most sensitive aspect of anthropogenic warming are glaciers. Experts agree quite unanimously that globally glaciers have not been this reduced for thousands of years. About 5000 years ago appears to be the time when glaciers were this short. And that is the reason many things buried in ice thousands of years ago are appearing now. Like Ötzi, the ice man from Tyrol, that is ~ 5200 years old. Some people believe this means our temperatures are like 5000 years ago. On the contrary I think glaciers are specially sensitive to CO2. The air above glaciers is very cold and very dry. The lower amount of water vapor makes it more sensitive to the increases in CO2. Despite higher winter precipitation and no appreciable changes in snow cover, the mass balance of glaciers is very negative.
Real skeptics don’t subscribe to any particular belief. They just trust the evidence. We have lots of evidence that our emissions are affecting the planet. Mostly in a good way by increasing the photosynthesis and decreasing water loss by plants, increasing forest biomass, increasing carbon sinks. That they affect also our climate is mostly a given. The warming is only partly caused by our emissions, and has some good aspects, as the higher temperatures are mostly beneficial, and there is a reduction of many extreme weather manifestations. It also has some bad aspects as everything in life. Heat waves are to become more frequent with higher temperatures, and high precipitation events also, as a warmer climate is a more humid climate.
When you see somebody embracing every positive aspect of CO2 and rejecting every negative aspect, he is not a skeptic. He is just a different type of believer.
A figure recently published by the UK Met Office that I modified to show a rule of thumb estimation of anthropogenic warming:

Reply to  Javier
September 25, 2017 6:25 pm

It essentially affects minimum temperatures more than maximum temperatures. It seems to affect night temperatures more than day temperatures. It appears to affect winter temperatures more than summer temperatures. It appears to decrease the rate of cooling more than increase the rate of warming. It appears to be more global while natural change is more regional.

You’re mixing up root cause. Min T follows dew points, dew points are following the ocean cycles.
RH dropped after the AMO positive cycle started In 2000, that was the step.
And land surfaces have been drying the air since.comment imagecomment image
And you can see water vapor reducing the cooling rate in net radition signal in this 3 day series of mostly clear skiescomment image
But it’s interesting that temps stabilize, net radiation drops by 60%, yet optical window still about -60W/m^2comment image

Reply to  Sixto
September 25, 2017 5:53 pm

I’d be glad to be convinced. There just isn’t any dispositive evidence. You see what you want to see.
Your example of glaciers doesn’t wash. What we actually see in glaciers is that those which have indeed retreated are where they were in previous naturally occurring warm cycles. For example, those Swiss passes which are only open during warm cycles show artifacts from Oetzi’a time at the end of the Holocene CO, from the Minoan, Roman and Medieval WPs. Perhaps you’re unaware that the ice in which Oetzi was found had moved downhill, so his remains have nothing whatsoever to say about the relative warmth of his time and now. The Holocene CO was demonstrably warmer than now.
Why should glaciers be especially sensitive to CO2? No evidence supports that article of faith.
When and if the Current WP ever shows three 50 year intervals warmer than the three 50 years intervals still warmer than any such interval in the Current WP, then maybe we can talk and try to tease out any human influence. But so far the Current WP has been cooler than the Medieval WP, as it was cooler than the Roman and the Roman was cooler than the Minoan. Hence, no detectable human influence.
Thanks very much for presenting what you think is evidence of man-made global warming due to CO2, but to me it’s not convincing and actually not even evidence.

Reply to  Sixto
September 25, 2017 6:02 pm

No I am not.
Javier presents no evidence. Just observations which he interprets as evidence.
Retreating glaciers reveal forests 1000, 2000 and 3000 years old. Less rarely the 5000 years which he finds to be evidence for a human fingerprint in the current warming.
IMO the preponderance of evidence shows that the Current Warming has so far been cooler than the previous warming cycles. Hence, no human fingerprint from higher CO2.
Science doesn’t do “proof”, although colloquially that term is sometimes used. It does confirmation and falsification. There is no evidence confirming the hypothesis that man-made CO2 has warmed the planet globally. And the hypothesis is easily shown false by every possible line of evidence.

Reply to  Sixto
September 25, 2017 6:14 pm

As I mentioned previously, allegedly greater radiative forcing (a dubious claim) is not exclusively consistent with more CO2. Better or at least competing explanations exist, as I pointed out.
For example, Gore claimed that retreating ice on Kilimanjaro was evidence of “global warming”. But there had been no local warming and deforestation was a superior explanation for that observation.
Similarly, Javier supposes that an alleged (by Warmunistas) exceptional net glacial retreat offers some kind of “evidence” of man-made global warming. But all the evidence in the world shows that supposition not to be the case. There is no evidence that temperatures now are higher than in prior warming cycles, nor any physical basis for the unsupported assertion that glaciers are particularly responsive to CO2. Were that the case, then the land ice which matters most, the EAIS, would not be gaining mass.

Reply to  Sixto
September 25, 2017 6:19 pm

My response is lost in cyberspace. This happens so often, that I’m probably going to quit commenting here.
I hope it does eventually show up, but even if it doesn’t, I’ll add that if glaciers were indeed super-sensitive to CO2, then they should all be retreating, which of course they aren’t. Major glaciers and every continent are advancing.
The same applies to the mass of the land ice formation which matter by far the most, ie the East Antarctic Ice Sheet.

Reply to  Sixto
September 25, 2017 6:21 pm

The evidence you are NOT looking for is obviously in scientific articles.
1. J. Oerlemans. Holocene glacier fluctuations: is the current rate of retreat exceptional? Annals of Glaciology, Volume 31, Number 1, January 2000, pp. 39-44(6)
“Integrations for a 10 000 year period, driven by random forcing of a realistic strength, show that the current retreat cannot be explained from natural variability in glacier length and must be due to external forcing.
2. Johannes Koch, John J Clague and Gerald Osborn: Alpine glaciers and permanent ice and snow patches in western Canada approach their smallest sizes since the mid-Holocene, consistent with global trends. The Holocene 2014 24: 1639
“Glacier retreat in western Canada and other regions is exposing subfossil tree stumps, soils and plant detritus that, until recently, were beneath tens to hundreds of metres of ice. In addition, human artefacts and caribou dung are emerging from permanent snow patches many thousands of years after they were entombed. Dating of these materials indicates that many of these glaciers and snow patches are smaller today than at any time in the past several thousand years.”
“The global scope and magnitude of glacier retreat likely exceed the natural variability of the climate system and cannot be explained by natural forcing alone. This departure is best explained by the ascendancy of another forcing factor – the increase in carbon dioxide and other greenhouse gases in the atmosphere.”
3. Goehring, B. M. et al. 2012. Holocene dynamics of the Rhone Glacier, Switzerland, deduced from ice flow models and cosmogenic nuclides. Earth and Planetary Science Letters 351–352, 27–35.
“After 5 ka, the Rhone Glacier was larger than today, but smaller than its LIA maximum extent. The present extent of the Rhone Glacier therefore likely represents its smallest since the middle Holocene and potential climate warming will lead to further rapid retreat of the Rhone Glacier.”
4. B. K. Reichert, L. Bengtsson and J. Oerlemans: Recent Glacier Retreat Exceeds Internal Variability. Journal of Climate 15 (2002) 3069.
“Preindustrial fluctuations of the glaciers as far as observed or reconstructed, including their advance during the Little Ice Age, can be explained by internal variability in the climate system as represented by a GCM. However, fluctuations comparable to the present-day glacier retreat exceed any variation simulated by the GCM control experiments and must be caused by external forcing, with anthropogenic forcing being a likely candidate.”
5. O. Solomina, W. Haeberli, C. Kull, G. Wiles Historical and Holocene glacier–climate variations: General concepts and overview. Global and Planetary Change 60 (2008) 1–9
“The finding of the Oetztal ice man in the uppermost part of a small glacier in the Austrian Alps clearly illustrates that Alpine glacier volumes (not lengths!) have become smaller now than during at least the past about 5000 years.”
6. Bakke, J., Lie, Ø., Dahl, S.O., Nesje, A., Bjune, A.E., 2008. Strength and spatial patterns of the Holocene wintertime westerlies in the NE Atlantic region. Global and Planetary Change 60, 28–41
“The retreat of maritime glaciers along western Scandinavia over the last century is unprecedented in the entire Neoglacial period spanning the last 5200 yrs.”
A) Koch & Clague 2006 meta-study of global glacier extent showing that current retreat exceeds the global range and minimum extent trend since mid-Holocene (Trend lines added). Notice how it shows glaciers now shorter than Medieval Warm Period and Roman Warm Period.
Koch, J., & Clague, J.J. 2006. Are insolation and sunspot activity the primary drivers of Holocene glacier fluctuations? PAGES News, Vol. 14 No 3 pp 20-21.
B) Thompson et al., 1995 study of the Huascarán glacier. Ice-core of the glacier with the temperature proxy showing that current glacier temperature is unprecedented for thousands of years and anomalous within trend.
Thompson, L.G. et al. 1995. Late Glacial Stage and Holocene Tropical Ice Core Records from Huascaran, Peru. Science vol. 269, 46-50.
Organic remains entombed in ice at mid-Holocene and freed by present global warming.

Reply to  Sixto
September 25, 2017 6:24 pm

My answer had too many links I think. Hopefully it will appear some time in the future.

Reply to  Sixto
September 25, 2017 6:29 pm

Worse is hard to imagine. But even when I copy and repost, many comments never show up. For long ones, it’s frustrating.
I have other things to do, and can’t afford to waste time, especially when so few people are liable to read my comments even when they do show up.
Plus, it’s disturbing that so much creationist cant is allowed here. It only reinforces the arguments of my acquaintances who equate CACA skepticism with creationism as equally anti-scientific.

Reply to  Sixto
September 25, 2017 6:30 pm

Javier September 25, 2017 at 6:24 pm
I know that too many links is a no-no, but those do usually appear after moderation. What bugs me is how many comments without any offending material simply disappear, never to reappear.

Reply to  Sixto
September 25, 2017 6:35 pm

micro6500 September 25, 2017 at 6:25 pm
Correct. Slightly warmer winters and nights is exactly what happened during prior warming cycles, with also perhaps some slightly higher summer day maxes. So how was the late 20th century warming any different from the early 20th century warming and the late 19th century warming, coming out of the LIA?

Reply to  Sixto
September 25, 2017 6:52 pm

I’ve been squelched for disrespecting “people of faith”, ie those who try to defend the Bible as science. I’ve seen others leave this blog because of its promotion of creationism.
I’m glad that you don’t get moderated, but I have been. Repeatedly. And other Christians who understand that the Bible isn’t science, but have been accused of being atheists because we know that fact.

Reply to  Sixto
September 25, 2017 7:04 pm

Yet again my comment has disappeared in cyberspace, without mention of moderation.
I’m outa here.
(I have looked through the Spam and Trash folders, NONE of your missing comments are there,could be a problem at your end?) MOD

Reply to  Sixto
September 25, 2017 7:08 pm

My understanding was that Oetzi’s body was in a naturally formed hollow, and as a result the flow of the glacier went over him. He was found pretty much where he died. If he had been caught up in the glacier itself, he would have been expelled after just a few hundred years.

Reply to  Sixto
September 25, 2017 7:10 pm

Posting a lot of posts in a short period of time seems to increase the chances of a post disappearing.

Dan Sage
Reply to  Sixto
September 25, 2017 7:48 pm

Mark W, that was my understanding also about Oetzi’s body.

Reply to  Dan Sage
September 26, 2017 8:28 am

I suspect that if that were not the case, the body would not have been in such pristine condition, and the associated artifacts would have not been so close by.

Reply to  Sixto
September 26, 2017 7:42 am

MarkW, the position where Ötzi lied was exposed 5000 years ago, and became exposed again now. If it had been exposed for any significant period of time in between Ötzi would have disappeared. Take a look at the bibliography provided if you want to know about Holocene glacier changes.
The figures that didn’t show are:comment imagecomment image

Reply to  Sixto
September 26, 2017 9:17 am

Javier, I was responding to Sixto’s claim that Oetzi’s body had been caught up in the glacial flow and had been found downhill from where he died.

Reply to  Javier
September 25, 2017 1:53 pm

I don’t know how the calculate the error, but if we can put little faith on the temperature values, much less on the error.

Reply to  Javier
September 25, 2017 2:56 pm

Hi Forrest,
The models never converge. It is little known, but if instead of anomalies, absolute temperatures are used, the models are all over the place, as they don’t agree on the temperature of the planet. They are aligned by anomaly at their multidecadal baseline. In this case 1961-1990, but there is no point at which they converge.

john harmsworth
Reply to  Javier
September 25, 2017 2:11 pm

What happens to this trend if its extended back to 1930? Back to 1650? This is just the tail end of a longer trend that absolutely has nothing to do with CO2 levels, at least before 1950. As such, I cannot ascribe any of it to CO2. It is only hypothesis. Perhaps only conjecture.

September 25, 2017 7:21 am

Whenever anyone, whatever technical background he or she has or does not have, says, “Accept the Science,” I stop reading. Science is not something to be accepted. Science is comprehended or not comprehended.
As a mechanical engineer who has dug into atmospheric radiation at length, I have learned that CO2 is already saturated less than three meters from the surface, and all this absorbed infrared radiation is immediately thermalized. So, the significant warming occurs only at the Top of Atmosphere, where 400 ppm has raised the altitude at which the atmosphere can radiate freely to space. How far was it raised, and how much more heat does the atmosphere contain since it is now radiating to space at a slightly lower temperature, and what did this do to the lapse rate? NO ONE CAN CALCULATE THIS.
Thus, all attempts to define Climate Sensitivity are based on the assumption that all warming since 1850 has been caused by CO2. Since this is a baseless assumption, no one has ever correctly calculated Climate Sensitivity.

Ian W
Reply to  Michael Moon
September 25, 2017 7:58 am

It does appear that there should be a small team of engineers validating the claims made by academic scientists, who, contrary to normal science, seem eager to prove rather than falsify their hypotheses.

Reply to  David Middleton
September 25, 2017 9:05 am

There is no way to learn whether it is 0% or 100%. We don’t really know why the temperature is what it is, now, much less what it will be in 100 years. In this area one man’s opinion is as good as another’s. Destroying prosperity seems like a poor option in this ambiguous environment.

richard verney
Reply to  David Middleton
September 25, 2017 9:36 am

Sorry to say that when I read your comment it appears that there is a lot of thinking where the word is being used as guessing/believing.
Whilst what you say may be reasonable, it may even be correct, but it is not science. There is nothing that displaces the null hypothesis that all observed change (if any change has been observed) is of natural origin.

Reply to  David Middleton
September 25, 2017 9:50 am

Michael, the natural factor is unknown, not unknowable.

richard verney
Reply to  David Middleton
September 25, 2017 12:33 pm

CO2 is a radiative gas, but that does not mean that it has any warming effect on a water world that is all but opaque to DWLWIR, and in Earth’s convective atmosphere.
Whether in Earth’s system, CO2 cause any warming, can only be determeined by observation, and to date no warming signal has been observed. That is why the IPCC does not state what the ECS (or TCR) is for CO2, and why it puts forward a speculative range. It is the reason why no standard text book that lists the properties of CO2, states that CO2 per mole results in X degC of warming. No one has made any measurement, so it is an unknown quantity, meaning that it might be zero.
You probably know that the Martian atmosphere has an order of magnitude more CO2 molecules than that in Earth’s atmosphere (if I recall correctly it has about 14 times as many CO2 molecules on a numerical basis). The CO2 molecules are more tightly spaced to one another in the Martian atmosphere (because Mars is a far smaller sphere), and therefore the prospect that LWIR emitted from the Martian surface being captured by a CO2 molecule in the Martian atmosphere and then a photon being re-radiated from that CO2 molecule and subsequently captured by another molecule of CO2 in the Martian atmosphere is far higher than the incident in Earth;s atmosphere, and yet Mars has no measurable radiative GHE. Why is that?
Even NASA concedes the reason why Mars has no measurable GHE is because the Martian Atmosphere lacks mass/lacks density/lacks pressure. NASA do not claim the reason why Mars has no measurable GHE is because the Martian atmosphere lacks molecules of so called GHGs.

Steve Keppel-Jones
Reply to  David Middleton
September 25, 2017 1:13 pm

“Destroying prosperity seems like a poor option in this ambiguous environment.
Fixed that for you, Michael Moon 🙂
Or, “Destroying prosperity seems like a poor option in this ambiguous environment except to progressive watermelons” also seems about right…

Reply to  David Middleton
September 25, 2017 5:05 pm

CO2 is well mixed, water vapor is mostly in the lower atmosphere and even then concentrated around the tropics.
In the areas where there is lots of water vapor in the air, CO2 has little to no impact.
In the areas with little water vapor in the air, it has more of an impact.

Reply to  David Middleton
September 25, 2017 5:12 pm

That should be true, but isn’t. The one region on earth where CO2 should outshine H2O is the South Pole. But it doesn’t, or at least hasn’t despite decades of the best possible observations.

Reply to  David Middleton
September 25, 2017 7:13 pm

Sixto, while the stations we do have in the Antarctic are top notch, there are about 2 orders of magnitude too few of them to support the claim that we have excellent data regarding what is happening down there.
Secondly, you still have the problem of CO2 not being the only thing that influences temperature.
You keep trying to prove that just because the CO2 signal is lower than the natural signal, that this proves there is no CO2 signal.

Reply to  David Middleton
September 26, 2017 7:54 am

“The radiative forcing effect of CO2 has been measured. It more or less matches the theortical value.”
What now? CO2’s “radiative forcing effect” is to raise the altitude at which the atmosphere can freely radiate to space. How does one measure that? As I explained, CO2 absorbs IR from the ground and thermalizes it within a few feet of the ground. At TOA, CO2 absorbs and re-radiates IR, making an opaque layer to 15-micron IR, which breaks up at some altitude. The higher this altitude goes, the lower the temperature at which the atmosphere radiates freely to space goes. Radiative heat transfer is of course determined by the temperature difference, which when radiating to space at Absolute Zero is the temperature of the gas radiating.
The CERES satellites would need to have a spectrograph capable of a line-by-line analysis of IR emitted by the atmosphere to be able to begin to measure this, which they do not.

Bob boder
September 25, 2017 7:24 am

Lukewarmer that thinks the small amount of warming caused by Anthropogenic CO2 is mostly positive and the atmospheric CO2 increase itself is clearly positive for mankind and the earth bio environment as a whole. BAGW Beneficial Anthropogenic Global warming. As I say over and over there is no C in AGW.

Reply to  Bob boder
September 25, 2017 11:47 am

BAGW…good description. We have to dispel the notion that CO2 is a pollutant. Otherwise soda drinks will be next on their hit list. Or by their reasoning then they should be, just to show how absurd some of the CAGW meme is becoming.

Bob boder
Reply to  Earthling2
September 26, 2017 7:27 am

They clearly want to reduce the number of humans on this planet into the millions to save it, so my guess is they already have come to that conclusion what’s 6 or 7 Billion people when you’re talking about saving the polar bears from having to change their diet a little.

Bob boder
Reply to  Earthling2
September 26, 2017 7:28 am

or should that be Chance the Gump?

Jimmy Haigh
September 25, 2017 7:24 am

Fence sitters.

D. J. Hawkins
Reply to  David Middleton
September 25, 2017 8:08 am

Yes. I suppose that I have to put myself in the Lukewarmer camp, since the increase in atmospheric CO2 appears to have an anthropogenic component, and the effect of additional CO2 is non-zero. I agree, I’m a “never-minder” when it comes down to cases, leaning to “yeah!” for a greening earth.

Reply to  Jimmy Haigh
September 25, 2017 8:27 am

That’s simply inaccurate, Lukewarmers like Ridley are extremely vocal about the Alarmists and the damage they are causing:
That is not sitting on the fence, is saying that we are doing a great deal of harm and the poor arebearing the brunt. What are you doing exactly?

Reply to  Jimmy Haigh
September 25, 2017 9:50 am

False dichotomy.
There is no reason why “We’re all gonna die” and “CO2 has no impact” should be the only options.

john harmsworth
Reply to  MarkW
September 25, 2017 2:39 pm

Except the actual evidence does not indicate any impact! Only some limited correlation.

Reply to  MarkW
September 25, 2017 7:14 pm

Not correct by a long shot. All we can say with any certainty is that the CO2 signal is less than the very noisy natural change signal. This is not proof that there is no CO2 signal, no matter how much you may wish it to be true.

Reply to  MarkW
September 26, 2017 12:35 am

Critics do not have to show there is no CO2 signal.
Global warming advocates have to show there is one.
They have failed to do this.
Normally that would be game set and match. Natural wins.
But the game rules get changed when the topic is green house guesses. Geoff

Reply to  MarkW
September 26, 2017 9:19 am

Warmists need to show that there is a CO2 signal and that it is large enough to worry about.
My only issue is with the religious belief that it is impossible for CO2 to have any impact on climate.

September 25, 2017 7:26 am

I am a complete laymen but I actually think lukewarmers do not help in the climate debate. If the global warming theory had not been espoused I would challenge anyone to understand whether the weather or climate had actually changed in the last 60 years. Certainly I don’t believe that the increase in CO2 is directly corelatable to temperature . I would argue that in the real world the only influence on temperatures are natural , whether that be sunspots, natural cycles or whatever. The only contribution that man has made to the temperature has been the obvious and clear amendments to historical and current data that has been done to suit the political narrative. It is clear this unexplained, arbitrary and suspicious manipulation of data represents at least 50% of the rise and perhaps as much as 100%. It is only a matter of time before a whistleblower exposes this deliberate and insidious fraud.
I think that rather than Lukewarmers rather than becoming warmists as the fraud becomes more evident they will become more passionate full blown skeptics. But even if lukewarmers don’t change the one area I do agree with them is that attempts to change the future climate, through taxes, or blowing up coal fired power plants or blighting the landscape with windmills or solar panels are doomed to fail and won’t impact on future temperatures.

The Reverend Badger
Reply to  David Middleton
September 25, 2017 1:08 pm

Did they all calculate the SAME value? Can we have a list with figures against names? (Just for amusement you understand, not going to run a sweepstake just yet).

john harmsworth
Reply to  David Middleton
September 25, 2017 2:46 pm

David, that is just more of “believe these smart people”. This site consistently proves that science is not about belief. It is about questioning. I’m not going to agree with you because other smart people do, and I’m disappointed that you would suggest it.

Reply to  David Middleton
September 25, 2017 5:21 pm

“Craig Idso, Roy Spencer, Richard Lindzen and Judith Curry have all calculated climate sensitivities to CO2 that are above 0 C.”
Yeah, but these *estimates* keep going lower and lower every time they look at them. How low can they go? Zero is a possiblity, wouldn’t you agree?

Reply to  David Middleton
September 25, 2017 7:15 pm

Zero can only be possible if the laws of physics get over turned.

john harmsworth
Reply to  Zigmaster
September 25, 2017 2:44 pm

Agreed! I can’t tell today’s weather from the 1970’s and I challenge anyone to say different anywhere in the world. Zero noticeable change in 40 years is a pretty damn poor catastrophe and precious little indication that anything is exceeding the potential of a system we barely (if at all) understand. Politics cum religion dressed up as science.

Reply to  Zigmaster
September 25, 2017 5:19 pm

“I would argue that in the real world the only influence on temperatures are natural , whether that be sunspots, natural cycles or whatever.”
That is the correct attitude for this subject. Heating and cooling of the atmosphere are from Mother Nature until proven otherwise.

Reply to  TA
September 25, 2017 7:15 pm

That’s as ridiculous a position to take as is the claim that CO2 is 100% responsible for the changes.

Reply to  TA
September 26, 2017 5:36 pm

“That’s as ridiculous a position to take as is the claim that CO2 is 100% responsible for the changes.”
It’s ridiculous to say it’s all Mother Nature until proven otherwise? That position doesn’t eliminate the possiblity that CO2 has some effect, all it says is until you have some evidence CO2 *does* add net heat to the atmosphere, you should go with Mother Nature as the cause.
There is NO evidence that human-caused CO2 is adding any net heat to the Earth’s atmosphere, so that leaves Mother Nature as the driver.

September 25, 2017 7:30 am

I’m a lukewarmer. For example, I think evidence shows we are growing more food with more CO2 in the air, and warmer temps in places like Russia, which just had record harvests. Positive effects should not be ignored when striking a balance. Many deserts are getting a bit greener.
Here is what would cause me to move toward alarmism:
1. Evidence that cyclones (hurricanes in N America) are getting larger in area, are more likely to be class 4 or 5, and drop more rain than in the past, to the point where hurricanes become considerably more economically damaging than in the past. This applies to cyclones world wide.
2. Evidence that very damaging (economically) weather extremes are becoming more common. Things like 20 inch rainfalls in 2/3 days in places that almost never used to get them. Or having such events occur fairly frequently in places where they had previously been rare.
3. Evidence that sea level rise is accelerating.
Of these 3, I think acceleration of sea level rise is least likely, I think it will remain close to about a foot a century, possibly even less. But I could be wrong, obviously.

Reply to  John
September 25, 2017 8:28 am

Obviously, none of those is evidence of climate change. Literally none. They are “symptoms” of climate change, but could be symptoms of something else.
I can spin scenarios where the trends for each of those phenomena would be higher or lower sans climate change. For example, as the Antarctic is what is known as an “artic desert”. Very little precipitation. As the air warms, even slightly, we could see more snowfall in Antarctica. Given this is the largest mass of land bound ice on the planet, this could reduce sea level rise.
So sea levels could rise…or fall with warming.
Damaging weather extremes? our record is spotty, and also there are more of us, with more infrastructure to damage, then ever before. Therefore economic measures of weather extremes are meaningless.
Storms form due to the difference in temperature between two areas (that is how “work” is created). Given climate change predicts the poles will warm faster than the tropics, this would reduce the temperature differential, reducing the size, and power of storms. So more storms = global cooling.
So, no, none of those phenomena definitively prove anything.

September 25, 2017 7:36 am

Ron Long has said it all. The climate is changing and it behooves us that windmills and solar panels are going to prevent climate change because the climate is going to change regardless (as that is what it does). All the citizens of earth (not just the rich countries) deserve cheap and reliable energy, cheap and reliable clean water. Give them both these things instead of devoting vast, copious, egregious sums of money to silly schemes that do nothing. Frack the gas, dig the coal and do it responsibly with minimal pollution but mostly do it for all those much less fortunate citizens of the planet to raise their living standards.

Reply to  ricksanchez769
September 25, 2017 9:53 am

Lomberg calculated that for the amount of money we spend each year trying to avoid a trivial amount of warming, we could provide clean water to every person on the planet.

john harmsworth
Reply to  ricksanchez769
September 25, 2017 2:49 pm

I think this sums up how most of us feel about the issue. Fantastic waste of resources for negative return in human terms, and hardest on the poor.

September 25, 2017 7:38 am

The 2016 El Niño should spike toward the top of the 2σ range, not toward the model mean.

Excellent point. I am looking forward to reading your next post.
Just a nick pick, though. Should it be “models mean” instead?

September 25, 2017 7:39 am

Sort of like AA: My name is Roger and I am a lukewarmer.
I would be inclined to alarm if the match between observed temperatures and model projections trends to a match over the next ten years especially because I worry that the temperature trend will be down.
Even in that case though, I don’t see any possible solution to the alleged problem simply because replacing fossil fuels is so expensive that the cure is worse than the disease. I think fossil fuels are the best thing that ever happened to mankind so even if there are problems with its use using fossil fuels we can afford to adapt to the problems.

Reply to  David Middleton
September 25, 2017 7:16 pm

A lot of things crossed my mid. Unfortunately a lot more decided to stay there.

Rick Pfizenmayer
September 25, 2017 7:45 am

Wouldn’t “Climate Realist” be a better description?

September 25, 2017 7:46 am

The gas pressure, volume, mass and temperature are connected. pV=nRT. Alarmists don’t need anything more than to show gas composition having a meaningful role in it.
In the meanwhile the effect of parts per million variations in the atmospheric composition on temperature is equivalent to homeopathy. Even without e.g. sudden changes in the volume none seems to be able to explain. https://science.nasa.gov/science-news/science-at-nasa/2010/15jul_thermosphere.

The Reverend Badger
Reply to  jaakkokateenkorva
September 25, 2017 1:16 pm

Thanks for the inspiration. I hereby lay claim to the new word;
————————- THERMEOPATHY ————————–
25th September 2017 21:12hrs UK
The Reverend Badger.
THERMEOPATHY – the scientifically nonsensical claim that small variations in trace gases in a planetary atmosphere can have a significant effect on surface temperature of the planet.

john harmsworth
Reply to  The Reverend Badger
September 25, 2017 2:51 pm

Beautiful, gentlemen, beautiful!

Tom Judd
September 25, 2017 8:11 am

Is Climate ‘Lukewarmism’ Legitimate?
Hell yes!

richard verney
September 25, 2017 8:18 am

Essentially, catastrophic alarmism is based upon the RCP8.5 pathway scenario, but observational warming is closer to the RCP 2.5 pathway scenario,
The author states:

Actual emissions are tracking closer to RCP 6.0. When a realistic transient climate response is applied to RCP 6.0 emissions, the warming tracks RCP 4.5…

Whilst the first figure supports that claim, it is so only because of the very recent warming associated with the strong El Nino of 2015/16, and it is material to bear in mind that the ENSO cycle has not yet completed and should a La Nina develop (as forecasts presently suggest for late 2017/early 2018), the temperature anomaly will then fall back so that temperatures/warming will once again be tracking the RCP 2.5 pathway scenario, as they were tracking in 2013/14 prior to the recent strong El Nino and when the pause was still current and being discussed in the literature.

richard verney
Reply to  David Middleton
September 25, 2017 12:37 pm

That I would agree with.

john harmsworth
Reply to  David Middleton
September 25, 2017 2:57 pm

So David, what is your boundary for giving up utterly on the fact that CO2 causes warming

September 25, 2017 8:19 am

Typical babbling nonsense from a science illiterate — how could we ever simply toss out the 9,200 peer reviewed papers in the last IPCC report they ask. Well, Google Scholar brings up 365,000 papers when searching for ‘Steady State Universe’, what does this suggest to them I wonder?