# New paper finds transient climate sensitivity to doubling of CO2 is about 1°C

A new paper published in Ecological Modelling finds climate sensitivity to doubled CO2 concentrations is significantly lower than estimates from the IPCC and climate models which “utilize uncertain historical data and make various assumptions about forcings.” The author instead uses a ‘minimal model’ with the fewest possible assumptions and least data uncertainty to derive a transient climate sensitivity of only 1.093C:

“A minimal model was used that has the fewest possible assumptions and the least data uncertainty. Using only the historical surface temperature record, the periodic temperature oscillations often associated with the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation were estimated and subtracted from the surface temperature data, leaving a linear warming trend identified as an anthropogenic signal. This estimated rate of warming was related to the fraction of a log CO2 doubling from 1959 to 2013 to give an estimated transient sensitivity of 1.093 °C (0.96–1.23 °C 95% confidence limits) and equilibrium climate sensitivity of 1.99 °C (1.75–2.23 °C). It is argued that higher estimates derived from climate models are incorrect because they disagree with empirical estimates.”

Otto et al find equilibrium climate sensitivity [over the next several centuries] is only ~1.3 times greater than transient climate sensitivity, thus the estimate of 1.093C transient sensitivity could be associated with as little as 1.4C equilibrium sensitivity, less than half of the implied IPCC central estimate in AR5 of ~3.3C.

Moreover, this paper does not assume any solar forcing or solar amplification mechanisms. The integral of solar activity plus ocean oscillations explain ~95% of global temperature change over the past 400 years. Including potential solar forcing into the ‘minimal model’ could substantially reduce estimated climate sensitivity to CO2 to a much greater extent.

• Empirical estimates of climate sensitivity are highly uncertain.
• Anthropogenic warming was estimated by signal decomposition.
• Warming and forcing were equated in the time domain to obtain sensitivity.
• Estimated sensitivity is 1.093 °C (transient) and 1.99 °C (equilibrium).
• Empirical study sensitivity estimates fall below those based on GCMs [Global Circulation Models].

## Abstract

Climate sensitivity summarizes the net effect of a change in forcing on Earth’s surface temperature. Estimates based on energy balance calculations give generally lower values for sensitivity (< 2 °C per doubling of forcing) than those based on general circulation models, but utilize uncertain historical data and make various assumptions about forcings. A minimal model was used that has the fewest possible assumptions and the least data uncertainty. Using only the historical surface temperature record, the periodic temperature oscillations often associated with the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation were estimated and subtracted from the surface temperature data, leaving a linear warming trend identified as an anthropogenic signal. This estimated rate of warming was related to the fraction of a log CO2 doubling from 1959 to 2013 to give an estimated transient sensitivity of 1.093 °C (0.96–1.23 °C 95% confidence limits) and equilibrium climate sensitivity of 1.99 °C (1.75–2.23 °C). It is argued that higher estimates derived from climate models are incorrect because they disagree with empirical estimates.

## 216 thoughts on “New paper finds transient climate sensitivity to doubling of CO2 is about 1°C”

1. Isn’t 1c around what would be expected from CO2 warming + no feedbacks?
Hilarious 🙂

2. Very close to Arrhenius’s final estimate. If the current calculation is correct, then it seems climate science took about 100 years to arrive back to where it started. 😉

3. johnmarshall says:

Past atmospheric CO2 content is very poorly covered. When measurements were taken they were mostly not believed. All studies seem to take the Calender 1948 paper as gospel but is it? No because of all readings available to him then he put a ceiling of 285ppmv as maximum. unfortunately 50% of readings then exceeded 285ppmv some by more than twice. This is not science but biased reporting.

4. justsomeguy31167 says:

They show no evidence that the new model with the higher figures is correct and improved. After the “step change” we have much more data thus it is more likely the correct number.

5. Greg Goodman says:

“leaving a linear warming trend identified as an anthropogenic signal. ”
While attempting to account for natural variability is good step, I don’t see the justification for assuming the resulting “trend” is AGW.
firstly the world has been warming for several 100 years, clearly there is a long term process independent of AGW.
Secondly, CO2 effect is not calculated to be linear.

6. Using only the historical surface temperature record, the periodic temperature oscillations often associated with the Pacific Decadal Oscillation and Atlantic
Multidecadal Oscillation were estimated and subtracted from the surface temperature

subtracted PDO ? wrong to do that.
Calling on Mr. Tisdale !:

7. Greg Goodman says:

This is just another attempt a ‘accelerated cosine warming’ :
http://climategrog.wordpress.com/?attachment_id=209
There are roughly two and a half cycles in the sample all they are doing is calling the difference of fitting a (inappropriate) linear model to 2 and half cycles to that of the recent rise.
http://climategrog.wordpress.com/?attachment_id=987
The second graph reproduced here is a joke. Having removed the fitted cyclic variability they then _selectively_ fit a linear ‘trend’ to 1950-2010. What about the rest of the data ??
There is huge deviation of this fitted trend to early part of the “residual” line that is dropping a fast as fitted trend is rising. That means there is a non-AGW variability that has still not been removed before selectively fitting a supposed AGW signal to the data.
Even with those huge errors in their method they arrive at a value half of IPCC claims.
I suppose it’s progress of a sort, inch by inch they are giving ground but it’s going to take decades before they finally admit CO2 sensitivity is sod_all +/- 50% .
I think Lindzen & Choi 2011 is probably the most accurate assessment yet and it is the outlier.
They were so far off anyone else’s work that I originally dismissed their result. I suspect a lot of people , even being object, may have the same reaction but the more I actually do calculations and look at the evidence, the more I’m convinced that they are correct.
http://climategrog.wordpress.com/?attachment_id=884

8. This paper jives with my comment about the last one. If 1950 to present presents the hockey stick, but does NOT contain the lengthy “periodic pauses” which were found to be present throughout the record then the models overestimate man-made warming significantly. This paper finds the same thing.

9. Greg Goodman says:

If they were to take the linear trend from 1880-1940 ( ie peak to peak of the harmonic components they have selected ) it may make more sense. They could compare that to 1940-2000 slope.
1840-1950 is just one and half cycles of “cosine warming”.

10. Alan Watt, Climate Denialist Level 7 says:

This is rather refreshing:

It is argued that higher estimates derived from climate models are incorrect because they disagree with empirical estimates.

11. Katherine says:

Since the temperatures have been higher before, how can anyone conclude that the current warming isn’t just a natural return to higher temperatures as part of the recovery from the LIA?

12. in 2002 we wrote:
“Without these speculated positive feedbacks, even a doubling of CO2 concentration would lead to a theoretical warming of only approximately 1º C.”
http://www.apega.ca/Members/Publications/peggs/WEB11_02/kyoto_pt.htm
BUT:
1. There are negative feedbacks, ECS, if it exists at all , is much less than 1C. Say ~~0.2C.
2. BUT CO2 LAGS temperature at all measured time scales, so perhaps we should not be talking about ECS (temperature sensitivity to atmospheric CO2), but rather the sensitivity of CO2 to temperature.
http://icecap.us/index.php/go/joes-blog/carbon_dioxide_in_not_the_primary_cause_of_global_warming_the_future_can_no
P,S, Greg Goodman – good comments here and on another thread. Good man. 🙂

13. Craig Loehle, it appears you removed the multidecadal cycles from global surface temperatures using a statistical model, not AMO and PDO data. Is that correct?

14. This might get snipped, but I’ll take a chance.
On 60/20 year sharmonic cycles employed.
Climate related indices are mish-mash of frequencies, a selection I used here (some time ago for another purpose) doesn’t have any noticeable presence of a 60 year component, while the 20 year one is likely to be the solar magnetic field (Hale) cycle of ~22 years, which shows a very strong presence. Another bunch is concentrated about the luni-solar period of about 18 years.

15. Russ R. says:

Just a reminder, while there is a “consensus” that warming is happening and humans are a cause, there is absolutely NO CONSENSUS on the value of climate sensitivity.
In the IPCC’s own words (AR5 SPM, Note 16): “No best estimate for equilibrium climate sensitivity can now be given because of a lack of agreement on values across assessed lines of evidence and studies”
“Lack of Agreement” is exactly the opposite of “Consensus”.

16. Russ R. says:

MY THEORY (critiques welcomed):
One potential source of disagreement between empirical, paleo, and GCM estimates for Climate Sensitivity (and Transient Climate Response) could be the recent unexpected behaviour of Antarctic sea ice.
Models (and common sense) suggest that as the planet warms, sea ice should recede. We’ve seen that in the Arctic, but the Antarctic has, for no apparent reason, done the opposite. I don’t know of any models that predicted an increase in southern sea ice, nor of any paleo instances of this occuring.
This recent unexpected behaviour would have the effect of changing the sign of ice albedo (IA) feedback, at least in the southern hemisphere, from positive to negative. and probably from positive to neutral for the planet as a whole.
The lower feedback in the southern hemisphere could explain the slower rate of warming observed there, and the overall lower warming observed recently, including the lower estimates of Climate Sensitivity (and TCR) derived from empirical methods.

17. tty says:

I have never been able to understand what ”equilibrium sensitivity” really is. It is supposed to be the effect of the injection of a quantity of CO2 into the atmosphere after the temperature change has reached equilibrium with the oceans. However this equilibration can’t be complete until there has been a complete turnover of the deep ocean waters through the thermohaline circulation, which takes on the order of 1000 years, and by that time all, or almost all, the CO2 will be gone from the atmosphere, into the biosphere, into the ocean waters, into carbonate minerals or into (inert) organic bottom deposits in lakes and oceans.
This decline of the CO2 level is universally modelled as an exponential decay that leaves a substantial proportion of the CO2 in the atmosphere indefinitely. I once asked a very eminent climate scientist how this could be true, since it implied that CO2 levels could only increase and never decrease over geologic times, while we know that on the whole the opposite is true. He told me that the model was only meant to be used over relatively short timespans, perhaps up to a couple of centuries.
So the equilibrium sensitivity is calculated by using a formula that explicitly is known not to be applicable to calculating the equilibrium sensitivity. I suppose that is about par for the course in ‘climate science’.
By the way: no I won’t tell the name of the scientist. He is already in enough trouble for occasionally deviating from the party line.

18. rgbatduke says:

The second graph reproduced here is a joke. Having removed the fitted cyclic variability they then _selectively_ fit a linear ‘trend’ to 1950-2010. What about the rest of the data ??

…saving me from having to make similar comments. Such as, what about running the data back to (say) 12,000 BCE? 500,000 BCE? 5,000,000 BCE? Not to establish the correspondence with CO_2, as we don’t have accurate global CO_2 estimates for more than the last 30+ years, perhaps even 60 years, but certainly not for 150 years (and well in to that stretch we learn more from proxies and might as well shoot for the longer time stretches). To establish a) the natural variability of the climate and b) to demonstrate trivially that there is no visible cyclic variability to remove in the general temperature record. There is no viable physical model that explains the cycles they are fitting that has the slightest predictivity across the geological or proxy-derived temperature record, and in a nonlinear chaotic system such as climate, the decadal oscillations are probably quasiparticle structure, that appears, disappears, and spontaneously alters in any sort of chaotic sequence.
This is just a more complex form of numerology of the sort that is regularly argued on WUWT pages. 1000 year cycles. 60 year cycles. 100,000 year cycles. 26,000 year cycles. Jupiter, Saturn, the Moon. ENSO. PDO. AMO. NAO. The solar cycle. We cannot build a credible deterministic or explanatory model for the climate because it is an insanely difficult computational problem, so we are reduced to numerology in one or two dimensions to explain a fractal, chaotic phenomenon with an enormous dimensionality.
I sometimes weep for my species. Oh wait! The clouds outside look just like a giant whale at this very moment! Whales are lucky! I’m gonna go buy some lottery tickets.
What could go wrong?
rgb

19. Reblogged this on Centinel2012 and commented:
This matches very closely with several other recent papers that show CO2 sensitivity at 1.o degree C or less!

20. Bob Weber says:

This is making a lot of sense – listen up!
“Moreover, this paper does not assume any solar forcing or solar amplification mechanisms. The integral of solar activity plus ocean oscillations explain ~95% of global temperature change over the past 400 years. Including potential solar forcing into the ‘minimal model’ could substantially reduce estimated climate sensitivity to CO2 to a much greater extent.”

21. Jim Cripwell says:

1. It is impractical to measure climate sensitivity at the present time. Therefore ALL numeric values quoted are nothing more than guesses, and have no place in science, physics.
2. No-one, and I mean no-one has measured a CO2 signal in any modern temperature/time graph. So it follows that there is significant data suggesting that the true value of climate sensitivity, however defined, is indistinguishable from zero.
All estimates of climate sensitivity have no place in true physics. Anyone who deems to call him/herself a physicist should shout it from the rooftops that ALL and ANY numeric values of climate sensitivity which ANYONE quotes are utterly and completely meaningless.

22. urederra says:

transient climate sensitivity of only 1.093C:

Three significant figures, LOL.
They should talk to Mosher’s friends at Antarctica to use this algorithm instead of the Bootstrap one. These computer modelling algorithms are much better than the one used to count white pixels. Apparently the error of Bootstrap algorithm could be of the size of Alaska, maybe.

23. Latitude says:

They needed a computer to draw a straight line??

24. Bruce Cobb says:

“Using only the historical surface temperature record, the periodic temperature oscillations often associated with the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation were estimated and subtracted from the surface temperature data, leaving a linear warming trend identified as an anthropogenic signal.”
It seems they jumped to an unwarranted conclusion. Firstly, as we all know, there is a warm bias in the temperature record, to the tune of as much as 50%. Secondly, and as they mentioned, no solar forcing was included since that is still a grey area. Thirdly, and the knockout blow is the fact that the warming stopped some 17 years or more ago, and we appear to be cooling now.
Even though this is a vast improvement over ipcc pseudoscience, it is still nonetheless pseudoscience. It still claims to see an anthropogenic signal, but it’s just a ghost, just not as scary a ghost as the ipcc’s.

25. edcaryl says:

rgb,
Exactly!

26. Early CO2 peak concentrations (pre 1950) are almost certainly understated because of smoothing during ice closure and CO2 loss during sampling. Surface instrumnet warming is clearly overstated. Thus this study would tell us only that climate sensitivity to CO2 doubling is close to zero if the input data is corrected.

27. Well, at least “about 1 degree” is better than “over 2 degrees”.
/grin

28. AJB says:

rgbatduke says: July 23, 2014 at 5:28 am
What could go wrong? Frequency 🙂

29. richard verney says:

If the pause continues for another few years, there will almost certainly not be an AR6.
As I commented some years ago, as the pause lengthens, there will be an ever increasing number of papers showing ever decreasing climate sensitivity figure.
The range for climate sensitivity has not been narrowed in 35 years notwithstanding billions of dollars thrown on this ‘science’ and as Russ R. says: July 23, 2014 at 5:17 am, there is now no consensus amongst the ‘leading’ climate scientists on this, which after all is the most important issue of all. The lack of consensus is because many of the leading climate scientists recognise that natural variation has been underassessed and observational data now coming in, suggests that climate sensitivity must be below 2.2. They know that if the pause continues (and many are openly saying that there may be no return to warming for a decade or so), that ‘best guestimates’ will lower that figure to less than 1.7, may be even less than 1.5.
If the pause continues, it will not be long before the majority of new papers are showing a range of say 1.3 to 1.8, then 1.2 to 1.7, eventually coming in with ranges of 0.8 to 1.3.
If that happens, AR6 will have to admit that the climate models got it wrong (most will by then have been invalidated having fallen outside the 95% level) and that best estimates for climate sensitivity is not a scarry figure. So I do not expect to see an AR6, especially as some Governments are already getting cold feet, and many Governments have yet to see the backlash that will arise from the needlessly hiked energy costs that are just coming home to roost.
Climate sensitivity is not a theoretical construct, but is the real world response to CO2 in the atmosphere as it plays out in the climate system of planet earth. This can only be ascetained by observational data.
But claims that we can assess climate sensitivity are unscientific. I do not accept that one can even begin to assess climate sensitivity from observational data, until you are in a position to eliminate in its entirety natural variation, and that would require us to fully understand what natural variation is, what it consists of, each and every constituent forcing, their upper and lower bounds, and how it plays out over the years etc.
Presently, there is no hard data that confirms that there is any climate sensitivity to CO2, if there is a signal it is lost in the noise. I am with Gregg, that it is likely once everything has panned out that CO2 sensitivity is sod_all +/- 50% How long it will take ‘them’ to admit that, is more debatable and will no doubt be influenced by whether we see a period of cooling over the coming years and decade. Cooling of just 0.1 to 0.15 degC would quickly tilt the table.
Of course, I do not know how long the pause will continue, and when there is a change whether this will be up or down, but if it is down, I consider it likely that the stack of cards will quickly fall.

30. Don Easterbrook says:

“leaving a linear warming trend identified as an anthropogenic signal. ”
Looking at the geologic record of climate oscillations over the past 15,000 years, it is readily apparently that natural oscillations completely dwarf any CO2 effect. Warming of 20 F in less than a century occurs several times and warming of 5-10 F repeats many times, all at very low atmospheric CO2. At present we really don’t know the proximate cause of these multiple, very abrupt, high intensity periods of warming (and cooling). Obviously, CO2 is not a factor in these climatic warming episodes, so how can we ascribe something ‘left over’ in models that don’t include a solar component? The GISP2 Greenland record shows that temperatures in Greenland were 2.5-5.5 F warmer for almost all of the past 10,000 years–certainly not driven by CO2.
Until we have a better understanding of what really drives these abrupt, intense climate changes, as well as longer term changes, how can we assign any value to CO2 sensitivity?

31. tokyoboy says:

“urederra says: July 23, 2014 at 5:50 am re: transient climate sensitivity of only 1.093C:
Three significant figures, LOL.”
That’s FOUR significant figures, IMHO.

32. KevinM says:

Meanwhile, almost 20 years ago…
November 16 1995
Dr. MICHAELS. I should say l am Associate Professor of Environmental
Sciences, and at 4:00 o’clock today , I will be given my promotion
seminar, so hopefully that will cgange in a very short period.
Controversy surrounding the issue of global warming is a classic
example of what I think is the normal and creative scientific tension
that exists between those who formulate models or hypotheses and
those who evaluate such models with observed data.
Unfortunately, this issue has evolved in a highly politicized climate.
For the last decade, a community of scientists, often referred
to as a small minority, has argued that, based upon the data on
climate change, the modeled warming was too large, and therefore
any intrusive policy would not be based upon reliable models of
global warming.
This view has been cast in a very negative political light, which
has had a chilling effect on scienti?c free speech.
At the same time, testimony has repeatedly been given in front
of this Congress that the modeled and observed temperatures were
broadly consistent. This view has been amply rewarded. Nonetheless,
these two views have never been reoonciled scienti?cally.
The early suite of models produced an average warming of about 4
degrees celsius for doubling carbon dioxide, and the data suggested
a much lower number, about 1 to 1.5 degrees of additional warming.
The most important development in the last two years is that it
is now acknow edged that the community that argued for the lower
numbers appears more likely to be correct. Moreover, it is apparent
that the climate model that was most heavily cited by the United
Nations in a special 1992 supplementary report on climate change
which was prepared specifically to provide technical backing for the
framework convention on climate change, it is now known that that
model was known to be making large errors in the forecast of current
temperature at the time of the adoption of the framework convention.
And yet this never entered into the debate surrounding that
issue.
These observations strongly suggest that the scientific review
process that bases these international agreements has been highly
flawed, or there may have simply been omissions in communicating
to responsible individuals how large the errors in these calculations
were.

33. Mike Jowsey says:

rgbatduke says:
July 23, 2014 at 5:28 am
Thank you doctor! Laughter is the best medicine.

34. If I “bold face” selected verbiage in the following quoted commentary, to wit:
————
Abstract
Climate sensitivity summarizes thenet effect of a change in forcing on Earth’s surface temperature.
Estimates based on energy balance calculations give generally lower values for sensitivity (< 2 °C per doubling of forcing) ………..
…….. than those based on general circulation models, but utilize uncertain historical data and make various assumptions about forcings.
A minimal model was used that has the fewest possible assumptions and the least data uncertainty.
Using only the historical surface temperature record, the periodic temperature oscillations often associated with the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation were estimated and subtracted from the surface temperature data, leaving a linear warming trend identified as an anthropogenic signal.
This estimated rate of warming was related to the fraction of a log CO2 doubling from 1959 to 2013 to give an estimated transient sensitivity of 1.093 °C (0.96–1.23 °C 95% confidence limits) and equilibrium climate sensitivity of 1.99 °C (1.75–2.23 °C).
It is argued that higher estimates derived from climate models are incorrect because they disagree with empirical estimates.

=====================
Then me thinks the above is little more than “neo-science fiction” criticizing itself.

35. Bob Weber says:

Richard V, there will not be an increase in temps beyond this solar “mini-max”. Once the Sun is definitely into the downhill slide towards solar minimum, cooling will become obvious, even to the most diehard warmist. Of course Al Gore & Co will be the last ones to notice, as the warmists do not pay attention to reality whatsoever.

36. richard verney says:

Jim Cripwell says:
July 23, 2014 at 5:49 am
/////////////
Your comment was not up when I prepared my comment. The last post up was rgb’s usual useful insight.
You are absolutely spot on. I had started using the fra** word to describe such claims, but then decided better of usiing such inflamable language, and decided to make my comment (But claims that we can assess climate sensitivity are unscientific) more neutral..
I do not see how claims about assessing climate sensitivity can be conducted with a straight face. It is a farce, pure and simple. It is not physics, it is not science, well at least not of the type that I was taught.

37. KevinM says:

“The early suite of models produced an average warming of about 4
degrees celsius for doubling carbon dioxide, and the data suggested
a much lower number, about 1 to 1.5 degrees of additional warming.”
That’s testimony to congress in 1995. What has changed?

38. ehhhhh….this paper is also wrong.
There is no man made warming.
If it is there it is so small that man cannot even measure it.
Note the graph on the bottom of the third table, obtained from a random sample.
http://blogs.24.com/henryp/files/2013/02/henryspooltableNEWa.pdf
(minima is supposed to rise when there is more GHG)
Must be natural
Cannot be not-natural.
If there were any man made global warming the graph should show less Rsquared something less than 1.
Oh happy day….

39. Eric Worrall says:
“Isn’t 1c around what would be expected from CO2 warming + no feedbacks?”
No, it is what is expected assuming net zero feedbacks. Big theoretical difference.
Considering how completely inaccurate positive feedback assumptions have been,
it is almost intellectually imperative that only empirical data be used.

40. steveta_uk says:

rgbatduke says:
July 23, 2014 at 5:28 am

This is just a more complex form of numerology of the sort that is regularly argued on WUWT pages. 1000 year cycles. 60 year cycles. 100,000 year cycles. 26,000 year cycles. Jupiter, Saturn, the Moon. ENSO. PDO. AMO. NAO.

You missed out LMAO and LMFAO.

41. Gamecock says:

richard verney says:
July 23, 2014 at 6:17 am
Climate sensitivity is not a theoretical construct, but is the real world response to CO2 in the atmosphere as it plays out in the climate system of planet earth. This can only be ascetained by observational data.
================
How can you say it is a “real world response” and then tell us, “Presently, there is no hard data that confirms that there is any climate sensitivity to CO2, if there is a signal it is lost in the noise.” What moves it from “theoretical” to “real” in your mind?

42. mjc says:

“urederra says:
July 23, 2014 at 5:50 am
Apparently the error of Bootstrap algorithm could be of the size of Alaska, maybe.”
I thought the area in question was only 200,000 sq km…or about the size of Nebraska.
But…wouldn’t a sensitivity of around 1 C per doubling mean that we’d need to hit 600-700 ppm CO2 to see much of anything?

43. Pamela Gray says:

The models went off the rail with their water vapor fudge factor. That factor is based on two sources of additional water vapor being added to the atmosphere: 1) evaporation from a warming ocean due to additional heating from downwelling longwave infrared radiation, and 2) evaporation from land surfaces (IE soil, etc) from extra warming due to the same anthropogenic process. Both of these processes do indeed take place. The ocean surface does in fact add water vapor to the atmosphere via evaporation. And land surface send moisture into the air as well. But what amount of watts does it take to do that to each kind of surface and does the very tiny amount of watts in just the anthropogenic portion of CO2 cause a measurable increase in this noisy otherwise natural process?
The physics behind this anthropogenic evaporation adding to natural atmospheric water vapor cannot be demonstrated under lab conditions sufficient to simulate anthropogenic additions to ocean and land surface evaporation. So it became a fudge factor in order to get the models to match the segment of the temperature series used to tune the damned things. On top of that, they had to add aerosols to tone it down, as if Earth actually provides a steady stream of aerosols in a nice neat package.
The error is in the models and it is such a glaring 1st grade error I remain gobsmacked that it continues to rule grant applications, research journals and political policy discussions.

44. Coach Springer says:

After 160 + years of the industrial revolution, we’ve doubled CO2 how many times?

45. mjc says:

“Coach Springer says:
July 23, 2014 at 6:48 am
After 160 + years of the industrial revolution, we’ve doubled CO2 how many times?”
What is ‘never’?

46. richard verney says:

Bob Weber says:
July 23, 2014 at 6:29 am
///////////////
You might be right.
I am one of those people who can see some similarity between solar activity and temps, but not necessarily full correlation, and, of course, correlation does not mean causation. The processes involved in how changes in solar activity may affect Earth’s climate are not well known and understood. I see no empirical observational data that shows that CO2 drives temperatures, and my gut (that unscientific barometer) tells me that the sun is likely to be a more significant player than CO2.
Predicting the future is always difficult. We do not know whether the sun will enter a prolonged period of quiet activity (although I would not be surprised to see that happen based upon available data), still less what that will do, and why, on planet Earth. The next decade or so could be interesting, and it is likely that we will learn a lot. If we do see a quiet sun, although many questions will be raised, it is likely to settle some of the debate.
Whilst the science brings me to tears, my biggest gripe is the political response to all of this. It is complete madness, since for the main part, the policies to do nothing to reduce gloabl emssions of CO2, and are accordingly entirely futile even if you consider CO2 emissions to be a problem.
Sooner or later the truth will come out, and the science will sooner or later reveal the truth (whatever that will be even if it is that AGW is real and is to some extent problematic). But it is the mad mad politically driven response which is inflicting real damage to the people, their life styles, their jobs and the economy, as well has holding back development and a decent life for those living in the developing world and 3rd world. These pople are owed better.
I do not like the cold, but I do hope to see some cooling merely to get some sanity back in what to do in an ever changing world, ie., adaption over mitigation. lets spend our money on doing something good, rather than wasting it on futile gestures.

47. JimS says:

Don Easterbrook makes the most sense, when he writes:
“Looking at the geologic record of climate oscillations over the past 15,000 years, it is readily apparently that natural oscillations completely dwarf any CO2 effect. Warming of 20 F in less than a century occurs several times and warming of 5-10 F repeats many times, all at very low atmospheric CO2. At present we really don’t know the proximate cause of these multiple, very abrupt, high intensity periods of warming (and cooling). Obviously, CO2 is not a factor in these climatic warming episodes, so how can we ascribe something ‘left over’ in models that don’t include a solar component? The GISP2 Greenland record shows that temperatures in Greenland were 2.5-5.5 F warmer for almost all of the past 10,000 years–certainly not driven by CO2.
“Until we have a better understanding of what really drives these abrupt, intense climate changes, as well as longer term changes, how can we assign any value to CO2 sensitivity?”

48. Craig Loehle says:

It does not appear that most commenters have actually read the paper–email me cloehle at ncasi dot org if you want a reprint.
As to bias in the instrumental data, I discuss that this would lower my estimate of sensitivity. As to going back 15,000 years–I do not claim that my model captures such long cycles, but only that it captures the bulk (not every detail) of the cycles of the period analyzed (150 yrs). My result agrees with most of the empirical sensitivity estimates. As to the whole process of estimating sensitivity being “unscientific” I do fear that there is a risk but the question is too important to do nothing–science is an iterative process and can’t wait until all factors can be perfectly accounted for. As to the validity of subtracting the natural cycles–if natural cycles gave part of the warming in the 1980s-1990s and part of the pause, why can we not subtract the natural cycles to see what is left over? To Tisdale’s question–no I did not use the PDO index directly but long-term data indicating a 60 yr cycle exists. If you don’t believe in cycles at all, then you are free to ignore this paper.

49. Greg Goodman says:

Vuc’ says: http://i.telegraph.co.uk/multimedia/archive/02983/gods-face0_2983566k.jpg
I didn’t notice the file name first time round. Cool pic. Looks like a renaissance painting 😉
“God” = Jehovah = Jove = Jupiter. ( aka , Zeus. )
Chief honcho or various pantheon’s and god of sky and thunder ( aka ‘climate’).
===
Now taking a more modern approach to astronomy, a few numbers ( best values, should be accurate to 9 or 10 sig.figs ):
pSaros= 18.0310284658705
pApsides=8.85259137577002
days_per_year = 365.25636
print 2/(1/pApsides+1/pSaros)
pApSaros=11.8749876715626
That is very, very close to Jupiter’s sideral orbital period. (fixed stars).
pJ= 4332.589 / days_per_year # = 11.861775658061

Now looking at how long these cycles take to drift in phase and come back into phase:
print 2/(1/pJ-1/pApSaros) = 21322 years
http://en.wikipedia.org/wiki/Apsidal_precession
“These two forms of ‘precession’ combine so that it takes over 21,600 years for the ellipse to revolve once relative to the vernal equinox” [Note this is the Earth’s apsides (perihelion/aphelion) now, not the the lunar perigee cycle. ]
Now I think that calculation shows that Jupiter is the primary cause of the precession of the terrestrial and lunar apsides ( which as the the most massive planet by far, would not be too unexpected ).
Lunar distance from perigee to apogee varies by about 15%, that is 45% in variation in tidal force. Jupiter is what is driving that eccentricity and how it’s line of action varies through time.
So while the tidal force of Jupiter is too weak to have a direct effect it does have an effect on Earth systems via the moon.
By Jove !!

50. Richard M says:

1) I suspect 1950 is used because that is when the IPCC states humans started to have a major impact. Hence, anything before that time would not be relevant.
2) It looks to me like this is an attempt to put a ceiling on the possible warming, not to claim they have the complete answer. This is extremely valuable in dealing with alarmists. The alarmists are still pushing 3-4C increases by 2100. If that is 1-2C (including the warming that has already occurred) then they are left with nothing on which they can base their demands for emission reductions.
3) This is almost identical to a computation I did a couple of months using the RSS satellite data as a source (TCR = .96C).
4) The fact that solar is probably some part of this number should not be a big concern at this time. First, we need to get some reality back into the situation. Only then will others be open to looking any deeper. I think this paper is a good step in that direction. It takes the “C” out of CAGW.

51. “(…) leaving a linear warming trend identified as an anthropogenic signal.”
Exactly. The AGW hypothesis in a nutshell. Assume as a premise that more atmospheric CO2 will lead to global warming. Find a warming signal. Assume it’s because of more atmospheric CO2. The argument has come full circle.
This is truly all they’ve got! And they just don’t see it themselves …
“Using only the historical surface temperature record, the periodic temperature oscillations often associated with the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation were estimated and subtracted from the surface temperature data (…)”
Hmm. A couple of pretty important details apparently passed them by. 1) The PDO is not a periodic TEMPERATURE oscillation. And 2) the AMO represents North Atlantic SSTa DETRENDED.

52. Latitude says:

Craig Loehle says:
July 23, 2014 at 6:54 am
====
Thanks Craig..

53. NONE of the general global temperature rise since the 50s (actually confined to the 25-year period 1976-2001) is because of any increase in atmospheric CO2. There is no such thing as a ‘climate sensitivity’ to CO2.

54. Cheshirered says:

richard verney says:
July 23, 2014 at 6:17 am
“Presently, there is no hard data that confirms that there is any climate sensitivity to CO2, if there is a signal it is lost in the noise.”
Thanks RV. Is there any worthwhile evidence to challenge this? Face it, CO2-driven ‘CS’ is 9/8 of bugger all. ‘Lost in the noise’ is exactly right.
‘Experts’ are faffing around pretending tiny, miniscule margins in CO2 concentrations are significant to temps on a planet-scale level. Ancient history all the way up to the current 17 year pause / humiliation shows that is outright rubbish. The only thing preventing legions of beneficiaries from acknowledging as such is their pride, hubris and pay cheque.

55. Jim Cripwell says:

richard verney, you write “I do not see how claims about assessing climate sensitivity can be conducted with a straight face. It is a farce, pure and simple. It is not physics, it is not science, well at least not of the type that I was taught.”
We agree. However, the claims of proper values of CS from estimates have been around so long that few people, including Craig Loehle, any longer bother to stop to wonder whether they are, in fact, writing complete nonsense, which they are.
I have been fighting this battle for several years, particularly on Climate Etc. With zero success. The idea that estimates are the equivalent of measurements is now so ingrained in the “science” of CAGW that it is almost impossible to remove it. I hope you will help me try. I feel like a lone voice, crying in the wilderness, particularly when the likes of Steven Mosher claim that there is no categorical difference between estimates and measurements..
It would be fantastic if Craig were to read our comments, and endorse what I/we are saying. I can live in hope, even if I die of despair.

56. evanmjones says:

Isn’t 1c around what would be expected from CO2 warming + no feedbacks?
Yup. The basic lukewarmer position.

57. Matt Skaggs says:

Dr. Brown wrote:
“This is just a more complex form of numerology[…]”
Dr. Brown, would you not agree that if the historical data is too sparse to be meaningfully analyzed in the frequency domain, then it is too sparse to conclude that multidecadal warming is NOT cyclic?
Dr. Loehle wrote:
“As to the whole process of estimating sensitivity being “unscientific” I do fear that there is a risk but the question is too important to do nothing–science is an iterative process and can’t wait until all factors can be perfectly accounted for.”
FWIW, that sounds exactly right to me.

58. ferdberple says:

It appears that the author is assuming:
1. that there are 60/20 year climate cycles, that persisted from 1850 to present
2. that the 1850 to 1950 period warmed due to natural causes
3. that any increase in warming post 1950, above the 1850-1950 rate is anthropogenic.
With these assumptions the author is able to get a reasonably good fit to observed temperature. However, it could well be that this fit is simply an accident. If not, then the model should have predictive value going forward.
It would be instructive to show what the model shows outside the 1850-2010 time frame.

59. Mike Jonas says:

They don’t know what the ocean oscillations do, so they don’t know how to subtract them from the observed temperature. Sure, they can see temperatures going up and down over 100 or so years, but they don’t know how much is ocean oscillation and how much is something else. On top of that, they assume that the cycles are identical (just look at tides or seasons or the solar cycle to see how absurd that idea is). But they go ahead and do the subtraction anyway. Then they assume that what’s left is all caused by CO2. Then they report the result to 3 decimal places (1.093). It’s a joke. But it’s no laughing matter that this is the depth to which a supposed branch of science has sunk.

60. Greg Goodman says:

Allan MacRae says:
“BUT:
1. There are negative feedbacks, ECS, if it exists at all , is much less than 1C. Say ~~0.2C.

P,S, Greg Goodman – good comments here and on another thread. Good man. 🙂

Thanks.
What is more, volcanic forcing is now _scaled down_ to hide the presence of the strong, topical, negative feedbacks.
Back in 1992 Lacis et al ( which included Hansen ) in a boringly, methodical paper derived an AOD scaling of 33 to convert to W/m^2
A few years later they reduced that to 21 to improve agreement with model output.
http://climategrog.wordpress.com/?attachment_id=884

61. mpainter says:

That scientists can still give serious regard to “climate sensitivity” when the last 17 years shows none shows how theory becomes fact and fact becomes ignored in this world of climate science.
When one considers that the late warming trend circa 1977-97 was due to increased insolation, not CO2, this “climate sensitivity business becomes farcical.

62. ferdberple says:
July 23, 2014 at 7:23 am
It appears that the author is assuming:
1. that there are 60/20 year climate cycles, that persisted from 1850 to present
2. that the 1850 to 1950 period warmed due to natural causes
3. that any increase in warming post 1950, above the 1850-1950 rate is anthropogenic.

There are thus four free parameters in this curve fitting exercise. “With four parameters I can fit an elephant” said John von Neumann. [“and with five, I can make him wiggle his trunk”].

63. Pamela Gray says:

The temperature rise, likely in whole, is I think due to discharge/recharge of heat stored in oceans. There is tremendous lag involved in discharge and recharge and is significantly driven via cloud patterns and oscillations related to shifts in large scale climate regimes. This means that in somewhat chaotic fashion, we can experience heat discharge over fairly long periods of time, leading to step increases in global temperatures. We can also experience, during that same time, a lack of recharge sufficient to sustain that rise in the long haul, eventually leading to a temperature pause followed by a fairly long period of declining temperatures. If the clouds enter into a clear sky regime, we can once again look forward to a recharged ocean and the long step wise period of increasing beneficial warmth.
What is unlikely to happen is a long period of stable global temperature where the stored energy is kept at a fairly constant level through periodic and fairly equal discharge/recharge events. My sense is that the normal course of events is somewhat biblical, IE periods of plenty interspersed with periods of suffering.
So I continue to wait for models that demonstrate how atmospheric systems lead to these herky jerky discharge/recharge events of life-giving heat wholly natural in process.

64. phlogiston says:

There’s a typo in the title itself, it should read:
New paper finds transient doubling sensitivity of CO2 to temperature change is about 1°C

65. Greg Goodman says:

“2) It looks to me like this is an attempt to put a ceiling on the possible warming, not to claim they have the complete answer. This is extremely valuable in dealing with alarmists. The alarmists are still pushing 3-4C increases by 2100. If that is 1-2C (including the warming that has already occurred) then they are left with nothing on which they can base their demands for emission reductions.”
Yes, I agree. Getting this published is a step in the right direction. But like I said at this pace it will take 10y to before anyone apart from Lindzen gets anywhere a realistic value.
However, I think we’ve reached a ‘tipping point’ now, hopefully things will accelerate and the AGW myth will “collapse” as quickly as Thwaite’s glacier is about to do 😉

66. Jim Clarke says:

These comments remind me of the quote attributed to Winston Churchhill – “Democracy is the worst form of government, except for all the others.”
This paper may still be full of guesses and assumptions that may turn out to be false, but it has less of them than the models and theories used by the IPCC and the warmest community. It realistically indicates a climate sensitivity to a doubling of CO2 of about 1 degree C, which certainly fits the observations better than those other models.
We are a contentious lot, and are prone to nit-picking. That is good for science, but not for policy discussion. I would rather show support for a paper that is at least more accurate AND would argue that CO2 is beneficial; with no requirement for regulation, than dis the paper as being ‘still wrong’.
Once the backwards notion that we must ‘reduce our carbon emissions to save the planet’ is dead and buried, I don’t care how much quibbling takes place over the science. We can argue over hundredths of a degree, minute albedo changes, magnetic field fluxes and ocean cycles until the cows come home, but let’s support the good science that undermines the regulation insanity, even if it is not yet perfect!
This paper may be the worst, except for all those papers that support the warmest agenda.

67. Greg Goodman says:

LS: “There are thus four free parameters in this curve fitting exercise.”
two harmonics ( 3+3 ) plus two linear ( 2+1 ) = 9
How many parameters does it take to model the movement of Focault’s pendulum in a museum in Paris?
Is global temperature variation more or less complicated than a pendulum?
Von Newman’s comment is intended as a caution , not an all purpose smart remark.

68. durango12 says:

Yes, ~ 1 deg for doubling is what it will turn out to be. It is actually fairly obvious if you look at the data objectively.

69. Greg Goodman says:
July 23, 2014 at 7:50 am
Von Newman’s comment is intended as a caution , not an all purpose smart remark.
So was mine, so was mine

70. The equation that incorporates the equilibrium climate sensitivity as its proportionality constant conveys no information to a policy maker about the outcomes from his or her policy decisions. This conclusion follows from the lack of observability of the equilibrium temperature and the definition of the “mutual information” as the measure of the intersection between observables. Also, The existence of an anthropogenic signal violates the prohibition on superluminal speeds in the theory of relativity, superluminal speeds being required for this signal to carry information to a policy maker about the outcomes from his or her policy decisions.

71. I sometimes weep for my species.
No need to.
Science: Few aggravated photons kicked out by a few agitated electrons, when reach human retina extort their revenge on more electrons, making the ‘fatty lump’ sitting in the said ‘species’ sculls, construct what some may refer to as a reality.
Then they build most complex electronic observing, calculating and displaying devices, again using more agitating electrons to observe and evaluate this so called reality.
Pseudoscience: in a relaxed and hustle free manner bypasses all tiresome intermediate stages and lets the ‘fatty lamp’ do what is meant to do.
One way or the other, any difference is entirely subjective.

72. Mike Maguire says:

This paper makes good sense to me.

73. It seems to me that the link that says
“Otto et al find equilibrium climate sensitivity [over the next several centuries] is only ~1.3 times greater than transient climate sensitivity,”
is not accurate, but should instead say
“Otto et al find equilibrium climate sensitivity [over the next several centuries] is only ~1.3 times that of transient climate sensitivity, ”
1.3 times greater means it is larger by 1.3 times the original amount, which doesn’t appear to be what is meant.

74. Frank says:

Eric Worrall says: July 23, 2014 at 3:51 am
Isn’t 1c around what would be expected from CO2 warming + no feedbacks? Hilarious 🙂
Don’t we live on a planet with significant feedbacks? In the regions that obviously are in rapid equilibrium with liquid water (cloudy skies and the boundary layer over the ocean), don’t we expect the amount of water vapor in the atmosphere to rise with temperature? We know lapse rate feedback will counter some of the water vapor feedback. Don’t you know that observations of outgoing LWR from space (especially in clear skies) show that seasonal global warming results in less emission of LWR from the TOA than expected for a climate with no feedbacks?

75. This does not hold water since CO2 always follows the temperature. So the amounts of CO2 in the atmosphere are governed by the temperature.
In addition past history clearly shows ice ages have occurred when co2 concentrations were much higher then today. Other big factors must be in play.

76. Bruce Cobb says:

durango12 says:
July 23, 2014 at 7:53 am
Yes, ~ 1 deg for doubling is what it will turn out to be. It is actually fairly obvious if you look at the data objectively.
No – It is doubtful we will ever know what the climate’s sensitivity to CO2 is, and we most certainly don’t now. There is nothing “obvious” about it at all, and “the data” is both incomplete as well as skewed.

77. Craig Loehle,
Valuable contribution to the dialog on climate sensitivity.
Your calm / measured communication of rigorous applied reasoning is wonderful.
John

78. Bruce Cobb says:

Jim Clarke says:
July 23, 2014 at 7:41 am
We are a contentious lot, and are prone to nit-picking. That is good for science, but not for policy discussion. I would rather show support for a paper that is at least more accurate AND would argue that CO2 is beneficial; with no requirement for regulation, than dis the paper as being ‘still wrong’.
I’m not aware of any policy discussion, and anyway, the ends don’t justify the means. “Support” in this case means that it’s a step in the right direction. But it’s still wrong. That is telling the truth, and that is what skeptics/climate realists do.

79. It amazes me how historical climatic data from solar variability to past temperature changes as Don Easterbrook correctly points out are ALWAYS ignored by AGW enthusiast.
They make up the data or cast data aside from solar variability to historical temperature trends /co2 concentrations to meet their needs.
If the data does not agree it is ether ignored or wrong. They must keep the hoax alive and mislead the public who in general are clueless in this area.

80. Greg Goodman says:

Loehle 2014: “A three-component model was fit to the Hadley global land and
ocean data for the period 1850–1950 (101 years) because IPCC has
stated that human effects on climate are only evident (detectable)
after 1950. The fit over the period was good (Fig. 1a). ”
“CO2 forcing alone. It is known from theory that CO2 should saturate
such that the CO2 forcing is proportional to the log of concentra-
tion. The log of an exponentially rising function (as CO2 is) is of
course a straight line, so the linear anthropogenic warming signal
detected by Loehle and Scafetta (2011) is in line with theory and
can be viewed as essentially capturing the CO2 signal. ”
ie of the form , which is indeed linear:
CO2(x)=log(280+k*exp(x-1950))
My earlier criticism, which applies to all IPCC type thinking as well as the present paper is that this still leaves notable decline at the end of 19th, ie there is still significant, non AGW variability in the record. Thus assuming late 20th rise is totally AGW is unfounded.
That is despite Hadley bias “corrections” removing 2/3 of the late 19th century cooling, inserting a post WWII cooling and generally making the SST part of the record more conformative to the IPCC story.
It seems the present paper is a middle of the road, intentionally simplistic, attempt to pull things in the right direction. It adopts most of the IPCC position and data ‘corrections’, so is not too controversial.
It got published, which is a useful step.

81. phlogiston says:
July 23, 2014 at 7:39 am
There’s a typo in the title itself, it should read:
New paper finds transient doubling sensitivity of CO2 to temperature change is about 1°C

Well that’s a smarta answer but of course is totally untrue as one would expect. Actually for sea-water and CO2 the “doubling sensitivity of CO2 to temperature change is about” 16°C.

82. sleepingbear dunes says:

rgbatduke and Don Easterbrook always give the discussion a needed inoculation of common sense. I feel better for it.

83. “A minimal model was used that has the fewest possible assumptions and the least data uncertainty. Using only the historical surface temperature record, the periodic temperature oscillations often associated with the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation were estimated and subtracted from the surface temperature data, leaving a linear warming trend identified as an anthropogenic signal. This estimated rate of warming was related to the fraction of a log CO2 doubling from 1959 to 2013 to give an estimated transient sensitivity of 1.093 °C (0.96–1.23 °C 95% confidence limits) and equilibrium climate sensitivity of 1.99 °C (1.75–2.23 °C). It is argued that higher estimates derived from climate models are incorrect because they disagree with empirical estimates.”
Typical – using incomplete ,inaccurate data and expecting a good result . Another model output another waste if time.

84. Salvatore Del Prete says:
July 23, 2014 at 8:33 am
This does not hold water since CO2 always follows the temperature. So the amounts of CO2 in the atmosphere are governed by the temperature.
In addition past history clearly shows ice ages have occurred when co2 concentrations were much higher then today. Other big factors must be in play.

Not while the earth has been in its current configuration, e.g. no isthmus of Panama. In fact over the last 800,000 years there’s no evidence of 300ppm being exceeded.

85. Steven Mosher says:

Goodman
“firstly the world has been warming for several 100 years, clearly there is a long term process independent of AGW.”
Clearly?
hardly.
I love when good skeptics stop examining all their beliefs. the assertions they make are clearly funny.

86. Tetragrammaton says:

But…but…but while the notion of transient climate sensitivity may be perfectly reasonable, the idea that it’s a universal constant number is almost certainly flawed. If one looks sideways at some of the recent papers written by the “old guard” climate science team, there seems to be a sub rosa acknowledgment that variable water-vapor content – particularly as regards cloud formation – has not been well integrated into their thinking, and hardly at all into their models. (See A.Lacis et al 2013, for example).
Maybe, they sometimes seem to be saying (although they never actually say it) , the actual value of transient climate sensitivity varies from as high as 3 or 4 to as low as -1. So it’s +1 in winter in dry air over the poles, 3 at night in temperate latitudes, -1 in the afternoon in the tropics, and so forth. Averaged out over a year, in may come close to the Cripwell assumption of zero. But then the next year may have a sufficiently different set of weather patterns that it comes to something else. And the year after that, there may be cosmic ray fluxes which cause more water-vapor nucleation and more clouds and hence more reflection of em radiation. As Professor Brown so aptly points out, it’s really, really complex.
So maybe the effects of CO2 as a greenhouse gas need to be described by a whole array of subsets of radiative physics, geared to particular micro circumstances of temperature, humidity, pressure, cosmic rays, etc. This will take a long time to figure out. In fact, it would be interesting for someone – preferably well-versed in the history and philosophy of science – to trace the evolution of “climate science” from Arrhenius to the current “consensus” mess, and then deduce how long it will take for all these “subsets” to be figured out. Another eighty years, perhaps?

87. Bart says:

Greg Goodman says:
July 23, 2014 at 4:26 am
“I suppose it’s progress of a sort, inch by inch they are giving ground but it’s going to take decades before they finally admit CO2 sensitivity is sod_all +/- 50% .”
+1

88. Steven Mosher says:

Dr. Loehle,
Thanks for doing this I always appreciate your work.
The other day I was reviewing another paper that estimated Sensitivity and it looked to me like it would be a cool idea to make the calculation into an online tool where people could play with numbers to see how that changed the estimate.
The sooner more people realize that working on the problem of estimating TCR or ECS is the most powerful step that skeptics can make, the sooner the charge of “denialist” will be seen as ridiculous.
But I fear that some skeptics will refuse to enter the debate. The science debate is
1. What are the best methods to bound our ignorance about sensitivity
2. what do those methods show.
3. what additional observations do we need to constrain the problem further.
Skeptics who address those issues are in the debate.
Nic Lewis and you are part of the debate because you address the question rather than
dismissing it.
You are part of the debate because you publish papers.
Some days i wonder where this debate would be if more energy and effort were put in by skeptics on the key question.. on actually addressing the issue on the debate table rather than dismissing it.
Instead they waste energy and time on peripheral issues.
Thanks for being part of the solution.

• Anthony Watts says:

That was a lucid and useful comment by Steve Mosher. It would be great if he could make all of his comments of this caliber.

89. Don Easterbrook says:

“Using only the historical surface temperature record, the periodic temperature oscillations often associated with the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation were estimated and subtracted from the surface temperature data, leaving a linear warming trend identified as an anthropogenic signal.”
“Moreover, this paper does not assume any solar forcing or solar amplification mechanisms. The integral of solar activity plus ocean oscillations explain ~95% of global temperature change over the past 400 years. Including potential solar forcing into the ‘minimal model’ could substantially reduce estimated climate sensitivity to CO2 to a much greater extent.”
I worry about any calculation that assumes ALL factors have been accounted for EXCEPT CO2 so what is left over MUST be CO2. Since no solar effects were assumed, isn’t what must be left after subtracting PDO/AMO cycles = solar + CO2? Subtracting PDO/AMO cycles doesn’t necessarily automatically include all solar factors. Some would argue that PDO/AMO cycles are not driven by solar variation and thus do not include a solar factor.
Natural climate changes in the geologic past have been huge compared to what we see now and what CO2 might be capable of, so how can we be sure that a small blip (like warming from 1978-2000) isn’t just natural? And what about climatic cooling from 1945-1977 and 2000-2014 during continuing rise of CO2? Does this not show that natural factors totally overwhelm any CO2 effects?

90. Greg Goodman says:
July 23, 2014 at 4:04 am
firstly the world has been warming for several 100 years, clearly there is a long term process independent of AGW.
If it has, it is not due to solar activity which does not show any trend the past 300 years:
http://www.leif.org/research/New-Group-Numbers.png

91. Leif Svalgaard says: July 23, 2014 at 7:37 am
…………
It was a great loss that von Neumann died in his early 50is, but on the other hand fortunate that a young student (Michael Minovitch) working during his summer vacation at the JPL probably never heard of the Neumann’s advice to Freeman Dyson.

92. vukcevic says:
July 23, 2014 at 9:51 am
on the other hand fortunate that a young student (Michael Minovitch) working during his summer vacation at the JPL probably never heard of the Neumann’s advice to Freeman Dyson.
Wouldn’t have mattered if he had or not.

93. Jim Cripwell says:

Steven Mosher writes “1. What are the best methods to bound our ignorance about sensitivity”
There is only ONE way to bound our ignorance. And that is to actually MEASURE CS. Since this is impractical at this time, the situation will remain the same. Intelligent people guess numeric values, all of which are meaningless.
Until we start applying the fundamental principles of The Scientific Method to this problem, we are merely spinning our wheels, and making absolutely no progress at all.
All these sorts of estimations do is give some sort of vague idea of what the MAXIMUM value of CS might be.

94. Latitude says:

1. What are the best methods to bound our ignorance about sensitivity
2. what do those methods show.
3. what additional observations do we need to constrain the problem further.
================
1. (a) based on a temp history that is so wonky it changes every time there’s a new run…(b) and constantly producing new science that says all of the old science was wrong
2. (a) and (b) both showed that we are constantly being lied to and the science is not settled
3. see (a) and (b)

95. If they used published temp series (which is what they look like), it’s still too high.
If you make the time series based on max temps (instead of average), there is no trend.

96. milodonharlani says:

No surprise to most here, but would be if it shows up in next IPCC report.

97. MichelE says:

The simple extrapolation in this paper tends to underestimate the TCR, as emissions of the past are supposed to have delayed effects.

98. george e. smith says:

So it’s only accurate to four significant digits.
When will they gat a better estimate we can trust ??

99. george e. smith says:

“””””…..1. What are the best methods to bound our ignorance about sensitivity
2. what do those methods show.
3. what additional observations do we need to constrain the problem further……”””””
#1 Why not measure it ??
#2 We don’t know its value.
#3 Need more observations of CS.

100. Here is the email:
Sent By: populartechnology
On: Feb 02/15/14 11:34 PM
Subject: No one noticed the new Loehle (2014) low climate sensitivity paper on the list?
A minimal model for estimating climate sensitivity
(Ecological Modelling, Volume 276, pp. 80-84, March 2014)
– Craig Loehle
Abstract: Climate sensitivity summarizes the net effect of a change in forcing on Earth’s surface temperature. Estimates based on energy balance calculations give generally lower values for sensitivity (<2 °C per doubling of forcing) than those based on general circulation models, but utilize uncertain historical data and make various assumptions about forcings. A minimal model was used that has the fewest possible assumptions and the least data uncertainty. Using only the historical surface temperature record, the periodic temperature oscillations often associated with the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation were estimated and subtracted from the surface temperature data, leaving a linear warming trend identified as an anthropogenic signal. This estimated rate of warming was related to the fraction of a log CO 2 doubling from 1959 to 2013 to give an estimated transient sensitivity of 1.093 °C (0.96–1.23 °C 95% confidence limits) and equilibrium climate sensitivity of 1.99 °C (1.75–2.23 °C). It is argued that higher estimates derived from climate models are incorrect because they disagree with empirical estimates.
REPLY: My daily email traffic is often overwhelming, and if I have to spend more time on my actual business and life than WUWT that day, some things might not make it to publication, or get lost in the traffic. Don’t feel slighted/ignored because I can’t read, respond to, or act on every email – Anthony

101. Robert W Turner says:

Plotting the vast number of CSs to CO2 over time would be interesting and quite possibly amusing. A statistical analysis of the estimates coupled with some creativity could lead to endless fun.

102. rgbatduke says:

You missed out LMAO and LMFAO

Um, where, exactly, are those decadal cycles to be found? Not that your “A” isn’t a potent source of methane, a well-known GHG…;-)

So it’s only accurate to four significant digits.
When will they get a better estimate we can trust ??

Sigh. No, it’s $1.093 \pm 0.2$ C. And proof that at least these climate researchers would lose points in my physics labs or any exams that required students to have a clue about significant figures in an answer.
But hey, at least they gave a — very likely completely unjustified — error estimate. Unjustified because in order for them to make an assessment of “95% confidence” they have to start by having a believable assumption for the distribution of error and the probability that the functional form that they are fitting is extrapolatable.
And that’s the rub, as Greg and I pointed out above. How can one assign “95% confidence” to any number extracted by assuming that reality is a sinusoid plus a linear trend, fitting that trend pre-1959 (only), then subtracting the extrapolated fit from the post-1959 data, fitting a linear trend to it, and assuming that this is the anthropogenic component of the post-1959 warming?
Try running the same trick backwards — to explain the proxy data prior to (say) 1850. Whooeee, doesn’t much work, does it, even over very short stretches into the past. Try running it back to (say) 1500 CE, and it becomes laugable. There is no physics-based explanation of the curve they are fitting, and if there were the physics would have to change radically and in unknown ways to work back to 1500, as then it would have to explain the Little Ice Age, and we can’t. Go back to 1000 CE and it is worse. Go back to 7,000 BCE (9,000 years ago) and their fit function is so far off from the linear trend alone that it predicts a profound ice age, not the Holocene Optimum 1-2 C warmer than today. So we know, beyond any doubt, that this model is utterly incorrect even a tiny distance outside of the fit interval. We know that our estimates of global average surface temperature are not precise to within 1 C anywhere. We pretend that the global average surface temperature anomaly is, when we know better, and ignore the fact that even if we know the “anomaly” relative to some baseline in the recent (35 year) past, our remote past anomaly knowledge is based on truly horrendous data extrapolations from increasingly imprecise and inconsistent data and therefore has enormous error bars, error bars so broad that they don’t really constrain any model very much, and error bars that are never drawn into any graph of the temperature anomaly lest the notion that we are certain of the warming be laughed out of the house.
So the improperly presented answer is has 95% confidence intervals based on Bayesian assumptions of the extrapolability of the model form fit and the assignability of the cause of the post-1959 surplus, assumptions that have a 2% probability (being generous) of being correct.
Right.
rgb

• rgbatduke commented
rgb, I really like your comments, I bet your classes are a joy (even if I’d get demerits for too many significant figures)!

103. Jim Cripwell says:

george e smith writes “#1 Why not measure it ??”
It is impractical to MEASURE climate sensitivity. It always was, and it will be into the indefinite future. That is why NO ONE, and I mean NO ONE has the slightest idea what its numeric value is.
Until it is recognized that I am writing the ONLY truth that matters on this issue, billions of dollars will go on being wasted trying to solve a problem that does not, and never did, exist,

• Jim Cripwell commented

It is impractical to MEASURE climate sensitivity. It always was, and it will be into the indefinite future.

Well, I don’t know about that, but we do have to stop throwing the data we have that might lend insight in the trash. Every day, the Sun comes up, warms the ground, and then it sets, and the temp drops. Every day! Even better, Extratropic the ratio of day to night changes, every day. One could take and graph how temp evolve through the year, look to see if the slope is changing. Oh wait, I’ve already done this:
http://wattsupwiththat.files.wordpress.com/2013/05/clip_image028.jpg

That is why NO-ONE, and I mean NO-ONE has the slightest idea what it”s numeric value is.

It’s very small. If you base it on actual surface temp measurements, and don’t throw the good bits away.

104. Bart says:

Steven Mosher says:
July 23, 2014 at 9:43 am
“The science debate is…”
Thus the elders of the Church admonished Galileo: If you will just concentrate on the number and placement of the epicycles, you will be part of the “debate”.
You want to be part of the “debate”, doncha’? All the cool kids are doing it.

105. Resourceguy says:

Let’s see what the AMO has to say about in a few weeks with another monthly number.

106. Jim Cripwell says:

Mi Cro writes “Well, I don’t know about that”
OK. HOW do you MEASURE climate sensitivity? No fiddling. Give me the nitty gritty of HOW you measure climate sensitivity.

• Jim Cripwell commented on

OK. HOW do you MEASURE climate sensitivity? No fiddling. Give me the nitty gritty of HOW you measure climate sensitivity.

You have to measure the change in rate of cooling at night as the length of day changes, then compare that year over year as Co2 changes. But, you have to understand what other things can change this, it is changing ( http://wattsupwiththat.files.wordpress.com/2013/05/clip_image028_thumb.jpg?w=963&h=725 ), but getting past this is beyond my ability (at least at this time) and available time.

107. Jim Clarke said
with no requirement for regulation, than dis {sic} the paper as being ‘still wrong’.
Henry says
What do you want us to do? Deny our own results?
http://blogs.24.com/henryp/2013/02/21/henrys-pool-tables-on-global-warmingcooling/
There is no man made warming. None whatsoever. There simply is no room for it in my equation.
Live with it.
Steven Mosher & company including our host [most probably] all have an interest to keep “the debate” going, even if they know there is no AGW,
as if there were not hundreds of other interesting debates we could have, scientific or otherwise.
{they only have to change the rules}

108. Bill Illis says:

The following charts are the historic CO2 sensitivity over the last 10,000 years, 200,000 years, 5 million years, 25 million years, 50 million years and 750 million years.
I’ve matched the timelines of the detailed global temperature estimates from dO18 isotopes with all the CO2 estimates which are available from reliable methods.
So, 2500 empirical datapoints pointing to +/- 40C CO2 sensitivity or randomness or something else is going on other than CO2.
http://s28.postimg.org/eucaualr1/CO2_sensitivity_last_10_Kys.png
http://s13.postimg.org/65wbml0p3/CO2_sensitivity_last_200_Kys.png
http://s10.postimg.org/4u651ipix/CO2_sensitivity_last_5_Mys.png
http://s23.postimg.org/3jnbzr9cb/CO2_sensitivity_last_25_Mys.png
http://s17.postimg.org/s2rwfp95r/CO2_sensitivity_last_50_Mys.png
http://s28.postimg.org/lovsbgt5p/CO2_sensitivity_last_750_Mys.png

109. Steven Mosher says:

“OK. HOW do you MEASURE climate sensitivity? No fiddling. Give me the nitty gritty of HOW you measure climate sensitivity.”
Simple.
Climate sensitivity ( Not sensitivity due to doubling) is defined as
lambda = Change in Temperature/ Change in forcing
climate sensitivity to doubling c02 is RELATED to this but not the same thing,
lambda = delta Temp / delta Watts
It is easy to measure. You just measure delta T and you measure delta W.
Then it gets more complicated, because you realize that the value can change as a function of time. then there are uncertainties.
Take temperature. we can clearly measure it, but when we look at longer time scales and global extent our measurements become more uncertain. we call these estimates. they are derived
from measurements and are more uncertain. but its knowledge nonetheless
Take forcing. here too we can measure it ( like TSI), but over long periods of time what we end up with are estimates with wide error bounds. but its knowledge nonetheless
for example looking at the past 150 years we could say
that temperature change might be as high as 1C and as low at .5C
and we say that changing in forcing could be between 1 and 3 Watts
Those are just example numbers to give you the idea,
So the real science debate that people can join is this
1. What is the real temperature change?
2. what is the real change in forcing and how much of it is human caused.
If you want to join the debate, then that is where the action is.
That is why Parliment calls Nic Lewis to discuss sensitivity and why they dont call you.
he joined the debate. you debate the debate.
The first approach is winning. Joining the debate works.
debating the debate? doesnt work.
So while some skeptics join the debate and get published and influence the IPCC (nic lewis) other skeptics debate the debate, never make a contribution to science, and waste their time on blogs, pounding a tiny drum that nobody hears.
personally, I’ll spend my time being productive. That means answering the change in temperature question as best I can.

110. Steven Mosher says:

Mi Cro says:
July 23, 2014 at 10:23 am
If they used published temp series (which is what they look like), it’s still too high.
If you make the time series based on max temps (instead of average), there is no trend.
########################
If you want to join the debate. Publish your work .
posting on the internet doesnt count.
looking at your work.. I can say it not publishable. sorry.

• Steven Mosher commented

If you want to join the debate. Publish your work .
posting on the internet doesnt count.
looking at your work.. I can say it not publishable. sorry.

No need to be sorry, I know it’s not. But I also know (well suspect) even if I put all of the bows and ribbons on it to get it published, a reviewer like you would reject it.
I also know that I lack abilities that would be required to get it to that point, as well as the free time to learn everything I need to know.
But, the data is good, and it is telling. And what BEST does is “wrong”, but so is what the rest of you are doing, so don’t feel bad.
Also I asked you the other day about the difference between publishing in a blog that is viewed and debated by very large numbers (and available to any scientist how is willing) and publishing in PLOS, but you didn’t answer.

111. Steven Mosher says:

Latitude
“Latitude says:
July 23, 2014 at 10:22 am
1. What are the best methods to bound our ignorance about sensitivity
2. what do those methods show.
3. what additional observations do we need to constrain the problem further.
================
1. (a) based on a temp history that is so wonky it changes every time there’s a new run…(b) and constantly producing new science that says all of the old science was wrong
False. the changes in the temp history are tiny and dont effect the end result in any material way.
Again, you can waste your time doing blog comments or actually do some work.
there is a reason why Steve Mc, Nic lewis, Anthony W, And Loehle get a hearing from folks.
they do work.
you are wasting your time because you are not changing minds.
Nic Lewis.. he is doing something. Craig Lohle? doing something.
Imagine if you devoted your intelligence to doing work rather than merely commenting.

112. Latitude says:

So the real science debate that people can join is this
1. What is the real temperature change?
2. what is the real change in forcing and how much of it is human caused.
====
1. what is the real temperature reconstruction/history?
2. (see #1)

113. Sun Spot says:

@Steven Mosher says:July 23, 2014 at 9:43 am, re: “Instead they waste energy and time on peripheral issues.”
Mosher, you mean peripheral issues like policy’s based on crap science that is costing us a fortune. I suggest you try to imagine a little harder as to why these peripheral issues are important !

114. Mike Maguire says:

While it’s clear that nobody knows anything for sure it seems hard to imagine that increasing CO2(being a greenhouse gas) is not having some effect on the temperature of the earth.
The planet has gone from 280 ppm to 400 ppm since the Industrial Revolution.
It’s also hard to imagine that humans burning fossil fuels have not been responsible for some or even most of that increase.
Those that state that CO2 followed temperature in the past are probably correct but humans were not around in the past to add the CO2 first, so we have a different problem to solve this time, which is determining what happens to global temperatures when CO2 goes up first.
There has likely been some natural warming, which could have contributed to some of the increase in CO2 but the problem is still the same:
When CO2 goes up X amount, how much warming does it cause?
As time marches on, we get more points to plot on a graph of CO2 vs global temperature. Natural cycles can be seen effecting temperatures related to the oceans and sun and at least to my eyes, are pretty obvious(like those related to the PDO/AMO).
Knowing this, we should be able to at least estimate how much of a contribution other known factors effecting temperatures are/were making and use this to whittle down natural/other influences left with time.
As a result, we should be able to gradually get closer to having just the effect of CO2 on temperature.
If there is no effect, as some speculate, then that will come out only after we discover what natural cycle caused all the unaccounted for warming.`
Until then, we have to use the known science and facts, that includes CO2 being a greenhouse gas and large human emissions of it.
Modest warming so far has been beneficial and additional modest warming, if it were to occur would be mostly beneficial. Global cooling always creates greater hardship to life on this planet.
It blows my mind that the massive positive contributions of CO2 in the known law of photosynthesis take a back seat to modest, beneficial warming(that has been twisted and spun into catastrophic outcomes)
Sunshine +H2O +CO2 = Sugars(food) + O2
Increase the CO2 and you get more food and O2.
Explosive vegetative health, plant growth and world food production/crop yields have resulted.

115. Latitude says:

you are wasting your time because you are not changing minds.
====
And I’m so humbled you took the time to reply to them anyway………….
“False. the changes in the temp history are tiny and dont effect the end result in any material way.”
…that is the biggest load of BS, which one are you referring to….the one that has temp increasing?…the one that has temps flat?….or the one that show temps decreasing?..or the one that gets changed every time there’s a new run?

116. Steven Mosher says:
July 23, 2014 at 12:09 pm
So the real science debate that people can join is this
1. What is the real temperature change?
2. what is the real change in forcing and how much of it is human caused.
If you want to join the debate, then that is where the action is.

Newsflash, you are not the arbiter of what the “real science” debate is.

That is why Parliment calls Nic Lewis to discuss sensitivity and why they dont call you. he joined the debate. you debate the debate.

So why did they call Donna Laframboise who has not published anything?

The first approach is winning. Joining the debate works.
debating the debate? doesnt work.
So while some skeptics join the debate and get published and influence the IPCC (nic lewis) other skeptics debate the debate, never make a contribution to science, and waste their time on blogs, pounding a tiny drum that nobody hears.

Right, because the skeptical influence in the Republican party that took control of the U.S. House of Representatives in 2010 and the repeal of a the carbon tax in Australia was all due to published science.

117. Jim Cripwell says:

Mike Maguire, you write “When CO2 goes up X amount, how much warming does it cause?”
I keep on telling you. No-one, and I mean NO-ONE has the slightest idea, because no one can measure climate sensitivity.

118. What can be concluded from THIS ?
Tropics, the North Temperate and the South Temperate zones have 3 different CO2 sensitivities.
Surprising to find the South TZ much warmer than the North one, while Antarctic is much, much colder than the Arctic

119. Jim Cripwell says:

Mi Cro, you write “but getting past this is beyond my ability (at least at this time) and available time.”
In other words, you haven’t the slightest idea. Why don’t you just agree with me that climate sensitivity CANNOT be measured?

• Jim Cripwell commented

In other words, you haven’t the slightest idea. Why don’t you just agree with me that climate sensitivity CANNOT be measured?

I know this is your White Whale, but there’s a difference between whether I think I can solve all of the issues in measuring it, vs whether I think it can be measured, which I do.

120. Latitude says:

Why don’t you just agree with me that climate sensitivity CANNOT be measured?
====
Jim, I will agree with you 100%……
We can’t even define climate sensitivity….you would have to do that first
..and measured against what?

121. Jim Cripwell says:

Seven Mosher, you write ” You just measure delta T”
How? How do you ensure that any measured Delta T was actually caused by a change in Delta watts? And the change was not caused by some other factor?

122. Berényi Péter says:

Transient Climate Sensitivity (TCR) is defined as the temperature increase at the end of a 70 year period, if CO2 concentration increased 1%/annum, so by the end it doubled (1.01^70 ~ 2).
Now, we do have empirical data for CO2 concentration of the past 55 years. It clearly shows average annual increase was substantially less than that, at about 0.427%. If this rate is extrapolated for the next 70 years, with a TCR of 1.093°C, it implies a further 0.467°C warming by the year 2084, which is 0.067°C/decade.
It is already less than alarming, so no policy whatsoever is needed to curb carbon dioxide emissions.
And that in case we are able to keep up exponential growth of energy generation from carboniferous geofuels for seven more decades, an unlikely scenario. It is far more likely we are forced to switch the bulk of plants to fifth or seventh or whatever generation nuclear, because one ton of ordinary granite, the default stuff continents are made of contains as much useful energy as fifty tons of coal plus 133 tons of atmospheric oxygen.
There is a huge difference between nuclear and nuclear. Instead of the 0.5% fuel efficiency of our current Cold War Plutonium factories we can go for a nearly 100% fuel efficiency, with a hundred times shorter average half life of radioactive isotopes left in waste. Ten thousand times less waste to store in the long run for the same energy output is not much. Also, we need not use high pressure reactor cores, ones at atmospheric pressure are entirely feasible. What is more, once turned off, they would not need active cooling, which increases their safety tremendously.
I can’t see energy shortage ever for the rest of the lifetime of the solar system.

123. Jim Cripwell says:

Latitude, you write “Jim, I will agree with you 100%”
Thanks. Now it would be nice to hear from Craig Loehle.

124. Alan Robertson says:

Steven Mosher,
I appreciate that you’ve taken a new approach, today and aren’t speaking in your typical cryptic quasi- aphorisms. However, you’ve told others that if they aren’t a publishing scientist, then there is no room for their voices in the debate. As a result, your posts today constitute a long- winded logical fallacy. For whatever kernel of truth you’ve expressed, more reasons exist to find fault with and work against the dictates inherent in your opinion.
Regards,
Alan

125. Jim Cripwell says:
July 23, 2014 at 11:12 am
george e smith writes “#1 Why not measure it ??”
It is impractical to MEASURE climate sensitivity. It always was, and it will be into the indefinite future. …

I was unaware that we even have a good, working definition of “climate sensitivity”, much less the ability to measure it. (whatever “it” is)

126. The majority of the warming post Maunder is due to an increase in solar activity which can be verified by looking at the historical data.
Presently the sun has gone from a very active state up to 2005 to a very quiet state post 2005. This will have climate implications.

127. Craig Loehle says:

Jim Cripwell: I do agree that it is difficult to estimate or compute (not measure) climate sensitivity–but there are ways to get at it. There are many approaches. My paper here merely demonstrates that if you simplify the problem you get a result that is in line with other empirical values (see my paper) and much lower than results based on climate models. I think that result is pretty robust.

128. REPLY: My daily email traffic is often overwhelming, and if I have to spend more time on my actual business and life than WUWT that day, some things might not make it to publication, or get lost in the traffic. Don’t feel slighted/ignored because I can’t read, respond to, or act on every email – Anthony

This is all a big waste of time.
REPLY: OK, then go waste time somewhere else if you feel that way. – Anthony

129. Greg says:

Steven Mosher says:
July 23, 2014 at 9:20 am
Goodman
“firstly the world has been warming for several 100 years, clearly there is a long term process independent of AGW.”
Clearly?
hardly.
I love when good skeptics stop examining all their beliefs. the assertions they make are clearly funny.
====
So if you can stop examining your beliefs for a minute and explain to me why global temps were dropping in the _residual_ and before AGW?
I don’t think there is any disagreement that it was colder in 1660 then 1900 ( before AGW ) , so what exactly are you objecting to in my statement ?
So far your ASSERTION that there is something wrong with what I said amounts to one word:
“Clearly? hardly.” [ the ‘clearly’ was mine ]
I love it when warmists try to refute a logical argument with a one word assertion and then accuse me of assertion. It’s really funny.

130. sleepingbear dunes says:

Mosher
I read your overly simplistic instructions on how to get climate sensitivity and then I read the comments by rgbatduke, Don Easterbrook and Dr Norman Page, then I realize you are telling us how to fly a balsa wood toy glider and they are explaining what is required to build & fly a 747. Not in the same league.

131. george e. smith says:

“””””…..Steven Mosher says:
July 23, 2014 at 12:09 pm
“OK. HOW do you MEASURE climate sensitivity? No fiddling. Give me the nitty gritty of HOW you measure climate sensitivity.”
Simple.
Climate sensitivity ( Not sensitivity due to doubling) is defined as
lambda = Change in Temperature/ Change in forcing……””””””
OK, I’ll bite. Just what “Temperature” (measured) is used in this calculation; who measures it, and how ?
And what is the “change in “forcing”, ” that is used in this equation, and where and how is it measured ??
So I’ve heard at least three definitions of climate sensitivity.
First one I recall reading was : “Increase in mean global surface Temperature, for a(ny) doubling of the atmospheric CO2 abundance.
After all, it is change in CO2 that is alleged to give rise to the strictly logarithmic dependence on CO2 abundance, that falls out of the Beer-Lambert Law (they claim). I thought that definition was the claim to fame of the late Stephen Schneider, of Stanford.
Then I heard it was the change in lower troposphere Temperature, rather than surface. The surface is surely the source of the LWIR radiant emissions, due to Temperature. The lower troposphere, being gaseous does not emit any LWIR radiant emissions, as a result of its Temperature (so they also say).
Then it was some LWIR radiant “forcing” in W/m^2 that was supposed to be used instead of CO2, and through some mystery, still retain a logarithmic relation to the Temperature change (any temp change).
Now last time I checked , Temperature and radiant emittance (W/m^2) are supposed to be related by a fourth power law; so how did that become a logarithmic relationship. And since “forcing” is supposed to be a small delta, then the fourth power law, degenerates to a linear one; which also is not logarithmic.
So yes I am mystified; so what are the SI units of “Forcing” and CS ??

132. Reg Nelson says:

Steven Mosher says:
If you want to join the debate. Publish your work .
posting on the internet doesnt count.
***************************************
So if I write a paper and publish it in a pay-for-play Indian journal, like BEST did, I’m allowed to enter the debate? Can I also announce my results a year before the paper is peer reviewed and go on a PR tour.

• Reg, That’s just harsh! lol

133. Bart says:

Steven Mosher says:
July 23, 2014 at 12:09 pm
“So while some skeptics join the debate and get published and influence the IPCC…”
Who cares about incremental influence on a corrupt organization focused on a potty hypothesis which has already been discredited to those with any intelligence? The IPCC isn’t going to change its tune until it can no longer carry it in the face of the mounting contradictory evidence, and there is nothing that anyone outside the organization can do to change that.
I do not care to debate epicycles. Nobody whose time is valuable should.
“[P]ersonally, I’ll spend my time being productive. That means answering the change in temperature question as best I can.
Just because you are engaged in an activity does not mean it is a productive activity. Indeed, if you are consuming resources which could better be spent elsewhere, you are decidedly unproductive.

134. Bob Bolder says:

Now the greens down in Venezuela at a UN conference are calling for the end of capitalism as a response to global warming.
It is getting, i think, obvious to almost everyone that there is no catastrophic feedback even the most ardent CAGW groupies are starting to realize it. They will now start to go totally loony and try to create as much havoc as they can to effect “social change” before they move on to something else.
We may quibble about how much CO2 contributes to Climate Change if at all, but as I have explained before the science, while interesting to us, was never that important to the people in the CAGW movement its just a propaganda tool nothing more. I don’t know if they will let it go or not but only time will tell.

135. Joe Born says:

sleepingbear dunes: “Not in the same league.”
It’s the Obama syndrome. Although to many of us it was blindingly clear right from the start that he was an empty suit, many otherwise apparently intelligent people paid attention to everything he said for seemingly the longest time.
My theory is there’s a huge variation in peoples’ relative responses to style and substance.. It’s fascinating. We students of human nature never run out of things to learn.

136. Greg Goodman says:

Mosh says:
Climate sensitivity ( Not sensitivity due to doubling) is defined as
lambda = Change in Temperature/ Change in forcing
climate sensitivity to doubling c02 is RELATED to this but not the same thing,
lambda = delta Temp / delta Watts”
Well for someone who sets out to “Start with the definition” you have not defined anything.
What “change” ? What is a “delta” if it’s not a change? Temp of what, land, ocean; what depth? Any attempt to relate a power term to temperature implies a heat capacity. SHC of land is about half that of ocean surface. To work out ocean HC you need to define what depth you are considering. Are you talking about a change in average temp or average change in temperature anomaly?
To relate a power term ( change or ‘delta’ rad ) to an energy term ( temp ) you need to be talking about the final equilbrium state, otherwise if it’s instantaneous, you should be comparing dT/dt to rad. or worse a mix of the two.
So if you nave an instantaneous delta Rad at a certain time how do you “measure” the delta T that it produces, separately from the, as yet unfinished temperature changes that are a result of more recent delta Rad.?
These concepts only have meaning inside a model, they are not measurable in a real system.
Of course you could try, as so many less able climatologists have done, to fit a linear regression to a dT / dRad scatter plot. First thing is, that is not a legitimate use of least squares regression and will give you the wrong answer leading to a too high figure for CS, secondly it is not even the correct ratio if you do manage to fit it since it’s an unknown mixture of the in-phase response ( that you are looking for and ) and the orthogonal ( dT/dt ) one that you don’t want. This was pointed out in Spencer and Braswell 2011 and other work by Spencer.
Thats without even considering the way the volcanic forcing has been ‘corrected’ to make climate models work:
http://climategrog.wordpress.com/?attachment_id=884

137. Bob Bolder says:

Steve Mosher says
Steve you need to grow up a little. The people that you are yelling at and that you don’t seem to think matter are the same people who put the pressure on your “ones in power” to listen to people like Anthony. They are the common people who may not have the opportunity to be academics but none the less are very capable of reading something and realizing it is bull, something frankly a lot experts can’t do because the get lost in the minutia of the subject. Many of these people are very good and find flaws in things and noticing fallacy. Those “ones in power” theoretically work for the same people you are ranting at and frankly my friend i don’t feel reading what you write that you are in any position to look down on anyone.
The “ones in power” don’t give a damn about what is right or wrong, good or bad, they only care how they can use it to keep them selves in power. Its the people here who actually care who are the ones who matter.

138. richard verney says:

vukcevic says:
July 23, 2014 at 9:51 am
Leif Svalgaard says: July 23, 2014 at 7:37 am
…………
It was a great loss that von Neumann died in his early 50is, but on the other hand fortunate that a young student (Michael Minovitch) working during his summer vacation at the JPL probably never heard of the Neumann’s advice to Freeman Dyson.
//////////////
You are right. There are some great minds out there.
Only last month, I watched a good BBC programme (they do make them occassionally) on Voyager. It was probably a repeat, celebrating that Voyager is now in inter stellar space. It was good to revisit some of the highlights of that grand tour.

139. richard verney says:

Phil. says:
July 23, 2014 at 9:15 am
Salvatore Del Prete says:
July 23, 2014 at 8:33 am
“….”
Not while the earth has been in its current configuration, e.g. no isthmus of Panama. In fact over the last 800,000 years there’s no evidence of 300ppm being exceeded.
///////////////////////
And yet we know that the Holocene Optimum was many degrees warmer than today (probably with an ice free Arctic),
We also know that the Minoan, Roman and Viking Warm Period (at least in the Northern Hemishere; there being no reliable data for the Southern Hemisphere so we do not know what the SH was like, but we know of no process whereby it would be significantly out of step with the NH) were some 1 to 2 degrees warmer than today, with Greenland and Northern Europe more generally (since we are finding similar archaeological evidence in Norway from glacier retreat) must have been 3 to 5 degrees warmer than today to enable farming settlements to exist where there are still glaciers today, and all this was achieved with CO2 not exceeding 300ppm!!
Natural Variation (whatever that encompasses) quite obviously has a large band, and can drive temperatures far higher than we observe today, and for that reason alone, we cannot rule out Natural Variation as being wholly responsible for the temperature trends measured these past 150 or so years..

140. Eliza says:

This is nonsense we dont even know if thre is ANY real worl atmospheric C02 +sensitivity y might be -negative for all we know. (Negative feed backs) Most of those graphs shown at the 9ICCC show C02 at 1000’s ppm during ice ages. This is again feeding the warmist trolls theory, but go ahead it really does not matter any more

141. richard verney says:

Bill Illis says:
July 23, 2014 at 12:07 pm
The following charts are the historic CO2 sensitivity over the last 10,000 years, 200,000 years, 5 million years, 25 million years, 50 million years and 750 million years.
//////////////////
Your charts are interesting, and onviously much work has gone into them, but they are not “the historic C02 sensitivity”.
As you note there is huge variability. Further
1). It is not known why the past temperatures were warm and to what extent this was due to natural variability rather than CO2; and
2). Whether the CO2 measured was a response to the then current temperatures, as opposed to the driver of those temperatures.
Until one can identify natural variation, and fully eliminate it from the observational data, one does not get a CO2/temp signal.
Even when you get such signal, you need to ascertain which is the horse, and which is the cart. There is considerable evidence that suggests that CO2 lags temperature at all time scales, and, if this is right, it is therefore the cart.

142. swifty says:

I find it difficult to see why noone has taken the opportunity to do an experiment using a 1 to several km long cylinder isolated in a vacuum and measure infra red spectral transmision at various CO2 concentrations as a function of distance instead of just lab measurements done over the cm scale. You would think the idea had occured to someone. Then just maybe we could talk data instead of squabbling. Guess I will have to do it myself?

143. pete says:

So Mosher, how exactly do we measure delta T? As soon as you start gridding you are no longer measuring, you are modeling.
How do we measure forcing?
How do we then attribute changes to T (assuming we can measure it) to changes in forcing (assuming we can measure it) with any certainty? At best we simply note they have coincided.
I’m not sure you have actually thought any of this through despite your attitude.
The illustrious rgb has it 100% correct.

144. Mike Jonas says:

Well at least the lousy paper has triggered an entertaining dialogue.
If you want to join the debate. Publish your work . posting on the internet doesnt count.“.
This blog comment was, of course, part of the debate, and it was posted on the internet.
Now, about the paper: some here like the paper because it counterbalances the AGW rubbish. That’s understandable, but it’s a political view not science-based. Some here like the paper because they think it gets the right result. That’s not science-based either. Wrong result = bad science. Right result for wrong reason = bad science. It’s a dreadful paper that should never have reached an editor let alone get past an editor and reviewers.

145. There are thus four free parameters in this curve fitting exercise.
============
I have no problem with curve fitting, so long as it has predictive ability. That is how a whole lot of science was discovered. A whole lot.
Curve fitting isn’t automatically wrong. It is almost always wrong, but not automatically. Sometimes someone hits upon the right combination, and the formula for the curve then becomes science.
I’m not saying this author is correct. Most likely not. However, we cannot simply dismiss curve fitting unless and until it has been tested outside the range of known data.

Just a note that the PDO was never integrated into the models because it wants discovered when the models were first formulated in the early 1990s. It changes everything.

147. Mervyn says:

It’s incredible that scientists cannot agree on the climate sensitivity to the doubling of the atmospheric concentration of carbon dioxide.
Perhaps everyone needs to get back to basics by referring to “The Infrared Handbook” published by the Office of Naval Research, a department of the US Navy.

148. rgbatduke says:

What “change” ? What is a “delta” if it’s not a change? Temp of what, land, ocean; what depth? Any attempt to relate a power term to temperature implies a heat capacity. SHC of land is about half that of ocean surface. To work out ocean HC you need to define what depth you are considering. Are you talking about a change in average temp or average change in temperature anomaly?

You are being far too kind even with these questions. One of the reasons that they cannot get climate models to work — one of many — is that they cannot specify initial conditions in the model sufficiently precisely, in part because nobody knows what the current “state” of the Earth is, in part because they would have to specify it to sub-centimeter resolution (the Kolmogorov scale for the dynamics is a few millimeters). Then, they know perfectly well that they are getting cloud dynamics wrong, in part because at their best grid resolution things like thunderstorms are literally invisible. And we could go on for hours simply tabulating our ignorance or the unverified approximations that are supposedly bandaids concealing it.
Then, as you note, there is “forcing”. We could speak for a while about lat/long gridding schemes mapped onto a sphere. Kriging and other means of data infilling might be worthy of volumes of specification and speculation, given the paltry number of observations we have to reconstruct a temperature record of the entire planet, to depth in both atmosphere and ocean, over hundreds of years (before taking over with proxies that commit logical and statistical fallacies almost from the start). And the beauty of it all is — it is impossible to be falsified! You can build any model you want, get any result you want, and nobody can prove you wrong! As long as you toe the party line, you can get published. If not, well, we’ve seen how the in-crowd applies pressure to get you fired (tenure or not) or marginalized. Build a model find something it gets right, declare success!
Of course, we can’t even measure a lot of the things the models are supposed to predict particularly accurately, and there are thumbs on all scales (in every sense of the word). Inconvenient facts are “re-examined” and shown to be false. MWP? Never happened. LIA? Sorry, the temperature then was actually rather flat. Never mind historical evidence, geological evidence, and the prevailing beliefs — bristlecone pines have the final word, by the time a hand-coded PCA scheme gets done with the data.
Climate science — with halfway decent data — is only around 30, maybe 40, years old. With less than halfway decent (but still global and electronically gathered) data perhaps another 30. Before that is the dark ages, open for exegesis and hermeneutics galore. Miracles abound. Thermometers aren’t to be trusted, and some of the trees have a lean and hungry look about them as well.
rgb

149. Latitude says:

rgbatduke says:
July 23, 2014 at 6:47 pm
Of course, we can’t even measure a lot of the things the models are supposed to predict particularly accurately…………..
===================
Sunday, July 20, 2014
New paper unexpectedly finds diverging trends in global temperature & radiative imbalance from greenhouse gases
Unsettled science:
A new paper published in Geophysical Research Letters finds that the radiative imbalance from greenhouse gases at the top of the atmosphere has increased over the past 27 years while the rate of global warming has unexpectedly decreased or ‘paused’ over the past 15+ years.
This finding contradicts expectations from AGW theory of increased ‘heat trapping’ from increased greenhouse gases. However, the finding is consistent with radiosonde observations showing that outgoing longwave radiation to space from greenhouse gases has unexpectedly increased rather than decreased over the past 62 years, inconsistent with more heat being “trapped” in the mid-upper troposphere.
http://hockeyschtick.blogspot.ca/2014/07/new-paper-unexpectedly-finds-diverging.html
I think they found Trenberth’s missing heat………..

150. Richard M says:

Leif Svalgaard says:
July 23, 2014 at 9:46 am
Greg Goodman says:
July 23, 2014 at 4:04 am
firstly the world has been warming for several 100 years, clearly there is a long term process independent of AGW.
If it has, it is not due to solar activity which does not show any trend the past 300 years:
http://www.leif.org/research/New-Group-Numbers.png

151. Richard M says:
July 23, 2014 at 7:33 pm
“If it has, it is not due to solar activity which does not show any trend the past 300 years:
http://www.leif.org/research/New-Group-Numbers.png

Good question. There is a puzzle here. We know that cosmic rays were still modulated during the Maunder Minimum, we know that there was significant solar magnetism even during the deepest part of the MM, we do not know why there were no visible sunspots, so there is, at this time, no good answer. If there was a change, it must have been rather abrupt, rather than a ‘trend’ over centuries. In addition, there are good arguments that the MM was not significantly different from what happens at every solar minimum, in particular the recent one: http://www.leif.org/EOS/2011GL046658.pdf

152. kim says:

My understanding is that the Maunder spots were ‘large, sparse, and primarily Southern Hemispheric.’ I think that Livingston and Penn explain ‘large’ and ‘sparse’ but not ‘primarily Southern Hemispheric’. I also suspect that ‘primarily Southern Hemispheric’ is a large clue to the climate effects of the sun on the earth.
=====================

153. swifty says
(proposes experiment)
Guess I will have to do it myself?
henry says
it is not as easy as you think.
CO2 absorbs and traps some LW IR
but it also absorbs and deflects some SW IR and even some UV [this is how we can detect it nowadays on other planets]
This is why I said that the closed box experiments [alone/only] are no good.
I explained this here
and you should try and understand all the basics first, before you design an experiment.
Anyway, my best guess is that the LW IR entrapment balances out against the cooling due to deflection to space since I could not detect any non-natural descend in the speed of minimum temps.

154. Leif Svalgaard says:
July 23, 2014 at 7:55 pm
There is a puzzle here. We know that cosmic rays were still modulated during the Maunder Minimum,…
It might be that the Earth’s magnetic field was responsible for GCR modulation during the Maunder minimum,
The earth has number of spectral components, strongest at 21 and somewhat weaker at 16,34 and 46 years, see comment:
the above numbers would give an average modulating signal at about 29 years. Hiroko Miyahara found that the MM’s GCR data show modulation magnetic cycle of about 28 years, as you can see here

155. richard verney says:

Leif Svalgaard says:
July 23, 2014 at 7:55 pm
///////////////////
Whilst not entirely germane to your point, but the interection between solar and earth, is not limited solely to how active the sun may or may not be, but rather how much much solar energy gets through to the surface of the earth, and changes in patterns of the receipt of that energy (eg., more being received over the ocean). Indeed, subtle changes in the patterns of the wavelength received could even be significant since the absorption of solar by the oceans is wavelength dependent in the sense that whilst the total energy absorbed may be the same (irrespective of wavelength), there could be subtle changes to the depth at which that energy is being absorbed (eg., at 50 cm, at 1m, at 5m, at 10 m, etc and so on), and this could impact on SST on a multi decadal time scale.
We also know that the Earth’s magnetic field has been weakening for some time, and not uniformally at that. There is the South Atlantic anomaly, which is weakening at a substantially faster rate (may be 5 to 10 times as quickly).
See generally the section on secular variation http://en.wikipedia.org/wiki/Earth%27s_magnetic_field,
and the recent data coming in from the swarm satellites. http://news.msn.com/science-technology/earths-magnetic-field-is-weakening-10-times-faster-now
and the South Atlantic anomaly: http://en.wikipedia.org/wiki/South_Atlantic_Anomaly
Now I am sorry to post, without knowing the detailed data on this, but has there been subtle changes in the amount of solar being received in the area of the South Atlantic anomaly? It coincides with an important part of the global conveyor belt and hence the heat transportation system, http://en.wikipedia.org/wiki/File:Corrientes-oceanicas.gif so changes here could have wider impact.
I do not know whether there are studies on it, and without data the point I raise is speculative, but I consider that one problem that arises whenever there is a discussion regarding solar, is that we do not know precisely what we are meant to be looking for, since we do not know whether there are some subtles, which presently we do not know about, in the planet’s relationship, and therefore do not understand what is going on, and why that is the case.

156. GabrielHBay says:

And so time marches on, and relentlesslessly, study by study, we come closer to that seemingly inevitable point when CS will be concocted as being zero +- something. No-one seems to mention the dreadful inconvenient ultimate conclusion that if CS == 0, AGE, at least as far as CO2 is concerned, is nonexistent? If that were to be concluded, does that mean the unthinkable, i.e. that all the lukewarmers here will have to become Sla***s or start arguing for higher CS? What a prospect! What entertainment awaits! Meanwhile we watch all the dancing with angels on pinheads pretending to not notice the looming shadow of the elephant…

157. John Finn says:

Mervyn says:
July 23, 2014 at 6:46 pm
It’s incredible that scientists cannot agree on the climate sensitivity to the doubling of the atmospheric concentration of carbon dioxide.

They actually do agree on the mean global temperature response to a doubling of CO2 (all other factors remaining the same). It’s about 1 deg C. This figure, based on multiple lines of evidence, was cited in the 1979 Charney Report. Garth Paltridge and Richard Lindzen both contributed to this report and both accept the ~1 deg C per 2xCO2 sensitivity figure.
The major disagreement relates to feedback – mainly from increased water vapour. “Sceptical” scientists such as Lindzen, Paltridge, Roy Spencer and Jack Barrett believe that any feedback effect is small and may even be negative. The AGW mainstream scientists believe that there is a strong feed back effect. To be fair, evidence from the LGM does offer them some support. However, recent observations (i.e. the temperature records) tend to suggest that the ‘baseline’ CO2 sensitivity figure is not far off the mark.
I haven’t read Craig’s paper yet, but it seems to confirm that the mean temperature is indeed increasing at a rate which is consistent with the base sensitivity.

158. John Finn says:
“Sceptical” scientists such as Lindzen, Paltridge, Roy Spencer and Jack Barrett believe that any feedback effect is small and may even be negative.
Why the quote marks around ‘skeptical’, John?
The only honest scientist is a skeptic, first and foremost. Alarmist scientists like Mann are not skeptics.
Furthermore: Lindzen is right, based on how the real world has responded. The small warming effect of rising CO2 is swamped by negative forcings. Thus, there has been no global warming for many years.
I believe what Planet Earth is telling us. What do you believe?

159. John Finn says:

Why the quote marks around ‘skeptical’, John?

The perception of “scepticism” or “skepticism” tends to be a bit varied on this blog. Lindzen et al are not necessarily sceptical of AGW but they are sceptical of CAGW (i.e. Catastrophic AGW).

I believe what Planet Earth is telling us. What do you believe?

My opinion now is the same as it has been for the past 10 years, i.e. that doubling the concentration of CO2 in the atmosphere will result in a mean global temperature rise of a shade over 1 deg C. This, very roughly, equates to an average trend of less than 0.1 deg per decade so I fully expect periods when the temperature increase due to CO2 is offset by natural variability.

160. richard verney says:

Further to the point made by GabrielHBay says: at July 24, 2014 at 12:25 am, whenever the issue of Climate Sensitivity is raised, one should not over look the fact that the only proper observational assessment of Climate Sensitivity is the one performed by Miskolczi (see his paper http://ruby.fgcu.edu/courses/twimberley/EnviroPhilo/SemiTransparentAtmospheres.pdf and http://www.friendsofscience.org/assets/documents/E&E_21_4_2010_08-miskolczi.pdf)
Miskolczi found Climate Senistivty (at current rates of CO2 of say 340ppm+) to be approximately ZERO.
As far as I know, it has never been established that this finding is wrong. It has been pointed out (by many) that some of the data on which his study and finding was based has issues . But heck, we are dealing with Climate Science, and there is not a single data set that does not have issues. You have to work with the data warts and all, but be aware that because it has warts and all, there are always uncertainties, and possibly wide error margins.
It is because all the data sets have issues, that no significant advancement in our understanding has taken place these past 35, or so years.

161. Bruce Cobb says:

John Finn says:
July 24, 2014 at 2:35 am
My opinion now is the same as it has been for the past 10 years, i.e. that doubling the concentration of CO2 in the atmosphere will result in a mean global temperature rise of a shade over 1 deg C. This, very roughly, equates to an average trend of less than 0.1 deg per decade so I fully expect periods when the temperature increase due to CO2 is offset by natural variability.
Such is the power and idiocy of a Belief system. Pretty awesome.

162. catweazle666 says:

Ah, climate science!
Cherry-pick a chunk of an obviously harmonic function, extrapolate the linear regression to death, and pluck a number out of a hat – not forgetting to incorporate a nice chunk of False Precision Syndrome. 1.093 °C ? FFS!
I’m just glad these people don’t design airplanes, or even hamster exercise wheels come to that.
But I’m only an engineer, so what would I know?

163. sleepingbear dunes says:

Some good stuff above. Leif says there is a puzzle here which perks up my ears and Latitude links Geophysical Research Letters findings about radiative imbalance at the top of the atmosphere. Good way to start the day.
I hope to hear more about GRL findings since it appears to be very significant. Am I interpreting it right?

164. John Finn says:

Bruce Cobb says:
July 24, 2014 at 4:01 am
John Finn says:
July 24, 2014 at 2:35 am
My opinion now is the same as it has been for the past 10 years, i.e. that doubling the concentration of CO2 in the atmosphere will result in a mean global temperature rise of a shade over 1 deg C. This, very roughly, equates to an average trend of less than 0.1 deg per decade so I fully expect periods when the temperature increase due to CO2 is offset by natural variability.
Such is the power and idiocy of a Belief system. Pretty awesome.

When I first began reading into the science behind AGW I was firmly convinced that the effect of CO2 was negligible. It’s clear to me now that this cannot possibly be the case. CO2 determines the altitude at which outgoing LW radiation is emitted to space. It, therefore, must influence the energy balance at TOA.
This is nothing to do with a “belief system” but an acceptance of basic physics. Richard Lindzen, Roy Spencer, Jack Barrett, Garth Paltridge et al also accept this same basic physics. If you’re going to start labelling those who “believe” the realities of the “greenhouse” effect as idiots. I’d suggest you become considerably more informed than you currently are.

• John Finn says:

CO2 determines the altitude at which outgoing LW radiation is emitted to space. It, therefore, must influence the energy balance at TOA.

I have no issue with this, but would suggest you find an IR Thermometer and point it straight up on a clear day.

165. Bruce Cobb says:

John Finn says:
July 24, 2014 at 5:39 am
This is nothing to do with a “belief system” but an acceptance of basic physics. Richard Lindzen, Roy Spencer, Jack Barrett, Garth Paltridge et al also accept this same basic physics. If you’re going to start labelling those who “believe” the realities of the “greenhouse” effect as idiots. I’d suggest you become considerably more informed than you currently are.
Right, we’ve seen your type of arguments here many times before. True to form, you mouth “basic physics” and “the realities of the greenhouse effects” in kneejerk fashion, as if they had anything to do with what is actually happening with our climate. I suggest you read up yourself. There are many resources available right here, as well as books. But I know you you won’t, because that would challenge your idiotic Warmist Belief system.

166. Bruce Cobb says:

If only the climate system would get on board with what it “must” do. Seems it has a mind of its own, more’s the pity.

167. Pamela Gray says:

Here are my opinions on this topic.
Well informed skeptics cannot deny the existence of atmospheric CO2’s ability to absorb and reemit longwave infrared radiation which is then transformed into heat not readily absorbed and used by land and ocean surface material as heat energy. However, to get our knickers in a twist over CO2 as the boogie man of warming is laughable. Water vapor is King, Queen, Rook, Bishop, Knight, and even the lowly pawn of greenhouse gasses. CO2 is nothing more than the dust that often collects on an unused chess board. Anthropogenic CO2 is the germ in the dust planted there by an opponent’s occasional sneeze.
Further, to say that greenhouse gasses are the end all be all of this chess game we call global warming is also laughable. The giant drivers on this Earth directly responsible for warming/cooling trends has little to do with greenhouse gas (in fact greenhouse gas POINTS to the drivers). Oceans absorb massive amounts of shortwave infrared, store it as heat, and emit longwave infrared. Land surfaces do too but land quickly uses SW IR instead of storing it. Oceanic and atmospheric teleconnections are the two players and sources of the temperature trends, plain and simple, either coughing up longwave infrared radiation heat into the atmosphere or absorbing shortwave infrared radiation which is then stored as heat. When the oceans cough up more warmth we warm up (and cloud up). When they spend more time absorbing solar SW infrared we cool off (and dry out).

168. Henry says
I have to agree with Bruce here.
John Finn, you are only denying what you know to be true, probably because your life [‘s work] depends on it.
Pam is right. There is no way that a change of 0.01% in the atmosphere (water vapor:0.5%) can do anything much to nature (i.e the sun). That is what made me investigate all of this for myself.
We [sceptics] know that even WUWT is trying to keep mainstream by [just] claiming there is a pause [in warming].They are only being able to keep up with this so-called “pause” by lengthening the time period which cancels the time when we still had warming.
Truth is there is no pause. Truth is that it has been cooling.
Most datasets show it is cooling from 2002.
My own 3 data sets show it it is cooling from at least 2000. Note the last graph on the bottom of the minima table.
http://blogs.24.com/henryp/2013/02/21/henrys-pool-tables-on-global-warmingcooling/
If there were any warming due to more GHG it should show up [as a factor in Rsquared on a random sample] especially on minima.
There is no AGW. It is cooling naturally. Just go or live with it.
Hopefully the wheel will turn up again
Chances are / history shows that somehow we could miss the actual [electrical?] switch
I have it that it should come around 2016, otherwise I donot know where we will end up
Keep praying that it will switch back to warming again.

169. I like Pamela Gray’s description of CO2. That puts it in perspective.
CO2 [“carbon”] is simply a non-issue. On net balance CO2 is harmless, and beneficial to the biosphere. There is no identifiable downside to adding more CO2 to the atmosphere. At both current and projected amounts, more is better. A slightly warmer world is good. A colder world is bad.
But the alarmist crowd cannot admit that, because then their entire argument — and the life work of many of them — becomes completely irrelevant. That’s gotta leave a mark.
So climate alarmists continue to sound their false alarm. Too bad for them that the planet does not agree. Even worse for them, the public is coming around to the skeptics’ view.

170. dbstealey says
At both current and projected amounts, more is better. A slightly warmer world is good
@dbstealey
Like an ostrich, you too are just putting your head in the ground, ignoring the damage that could befall all of us if global cooling continues {as it will}. You honestly do not have not a clue [about the relevant science] if you think that putting more CO2 in the air will make it warmer on earth.

171. HenryP,
I don’t call you an ostrich just because we have different views. I also don’t understand how your comment relates to mine. I wrote: a colder world is bad. What is your objection to that?

• HenryP commented

do you have an opinion as to when it will start warming again?

Once the Arctic starts to ice over again. As open arctic waters is the global cooling system.

• HenryP commented

I wonder how it is that you know why?

Open Arctic water radiates far more energy to space than it take in, and far more than an icy Arctic.
iirc you think this cause more precipitation/snow altering the albedo, which seems reasonable, but if I had to pick, I’d say that is a feedback to the already open water.

172. HenryP says:
There is no AGW. There never was.
That is only an assertion. Just as I routinely point out that there is no measurable, testable scientific evidence to support AGW, likewise there is no such evidence that decisively refutes AGW.
It is my understanding that AGW exists, but it is too small to measure. That view is shared by various people such as Prof Richard Lindzen and Anthony Watts. To assert that “there is no AGW” oversteps current scientific knowledge.
I am still waiting for a definitive measurement of AGW. So far, no one has been able to provide one. But that does not mean there is, or is not, AGW. Radiative physics provides a rational argument that CO2 causes some minor global warming. But the question has not been decisively settled either way.
~ the ostrich

173. dbstealey says
likewise there is no such evidence that decisively refutes AGW.
henry says
but there is. I found it myself.
On the bottom of my last table.
http://blogs.24.com/henryp/files/2013/02/henryspooltableNEWa.pdf
There is no room for any AGW in my equation. Natural warming and cooling is 100% natural.
Check the worry in my eyes if nobody put it in a paper

174. John Finn says:

HenryP says:
July 24, 2014 at 8:39 am
Henry says
I have to agree with Bruce here.
John Finn, you are only denying what you know to be true, probably because your life [‘s work] depends on it.
Pam is right. There is no way that a change of 0.01% in the atmosphere

Dear Henry
Try this little experiment. Take a container and fill it with a litre of water. Note that you can see the bottom of the container because the water is transparent to visible radiation. Now add a few drops of milk to the water and stir. Now you will be unable to see the bottom of the container because the milk has increased the opacity to light of the water. The concentration of milk required to do this is less than 500 ppmv.
Alternatively, you could try a slightly riskier experiment and simply add 400 ppmv of arsenic oxide to your tea or coffee (suggestion provided by Craig Bohren)

John Finn, you are only denying what you know to be true, probably because your life [‘s work] depends on it.

I am retired and you are making a fool of yourself.

175. John Finn says:

HenryP says:
July 24, 2014 at 8:39 am
Truth is there is no pause. Truth is that it has been cooling.
Most datasets show it is cooling from 2002.

No they don’t. There may be slightly negative trends in some of the datasets but the trends are NOT significant. This again supports the low sensitivity hypothesis since we have low solar activity and cooler PDO anomalies – yet mean global temperatures are essentially flat (i.e. NO warming but NO cooling either).
Incidentally your own dataset sample of stations is garbage. Too many of your stations are concentrated in small regions, e.g. 33% of your SH stations are in South Africa. South Africa represents only about 2% of total SH land mass.

176. @Mi Cro
There is a cycle which we know to be true as the Gleissberg
87-88 years
e.g.
http://www.nonlin-processes-geophys.net/17/585/2010/npg-17-585-2010.html
[from various investigations] I have been able to establish where we are in that cycle,
comparatively speaking, i.e. we are now ca. 1925
we know from eye witness reports that in 1923 it was still melting ice up there
If all goes well, and all planets arrive in time, global warming should start up again in 2038
You can figure the rest out for yourself
(1935-1950 was very cold)

177. John Finn says
1) There may be slightly negative trends in some of the datasets but the trends are NOT significant
2)Incidentally your own dataset sample of stations is garbage. Too many of your stations are concentrated in small regions, e.g. 33% of your SH stations are in South Africa. South Africa represents only about 2% of total SH land mass.
Henry says
1) Some? 4 global data sets against how many you have that goes the other way?
2) I explained the sampling technique at the beginning of the tables =longitude does not matter as we are looking at the change in K/annum
Get with it John, or stay in retirement.

178. HenryP,
Let’s just disagree, because I see nothing that decisively *refutes* AGW.
I have long said that AGW is too small to measure. And it is; no one has ever posted any measurements quantifying the fraction of a degree of global warming caused exclusively by the rise in anthropogenic CO2. Therefore, AGW remains a conjecture — only the first step in the hierarchy: Conjecture, Hypothesis, Theory, Law.
AGW is not a hypothesis, because a hypothesis must be able to make repeated, accurate predictions [that does not necessarily make all hypotheses valid; the Greeks epicycles accurately predicted the movement of planets, but that hypothesis was falsified by Kepler]. AGW has never made repeated, accurate predictions. For example, no climate model was able to predict the current halt to global warming for almost twenty years.
On the other hand, I do not see where your tables demonstrate conclusively that AGW cannot exist. I’ll stop now, because I am getting too close to agreeing with John Finn. ☺
~ the ostrich

179. @dbstealey
there is no noise in the data
everything is according to [a natural] plan
live with it
[perhaps you have a problem with the idea that everything goes according to a plan]

180. John Finn says:

Pamela Gray says:
July 24, 2014 at 8:01 am
Water vapor is King, Queen, Rook, Bishop, Knight, and even the lowly pawn of greenhouse gasses.

Water Vapour has very little influence in the higher, drier colder layers of the troposphere. Here CO2 is the only player (see emission spectra at the link below). As CO2 accumulates in these colder layers emission from the gas is reduced (as calculated by the S-B equation). This means there will be an imbalance, i.e. there will be more energy entering the system from the sun than there is energy leaving the earth’s climate system. To restore the energy imbalance the surface and lower atmosphere must warm.
http://climateaudit.org/2008/01/08/sir-john-houghton-on-the-enhanced-greenhouse-effect/
Scroll down to the upwelling spectrum graph (Fig 3) and note the CO2 funnel at the colder layers. Now read Steve McIntyre’s comments below the graph.
The large notch or “funnel” in the spectrum is due to “high cold” emissions from tropopause CO2 in the main CO2 band. CO2 emissions (from the perspective of someone in space) are the coldest. (Sometimes you hear people say that there’s just a “little bit” of CO2 and therefore it can’t make any difference: but, obviously, there’s enough CO2 for it to be very prominent in these highly relevant spectra, so this particular argument is a total non-starter as far as I’m concerned. )
Without CO2 there would be a lot less water vapour. The warmists are right about that.

• John Finn commented

As CO2 accumulates in these colder layers emission from the gas is reduced (as calculated by the S-B equation). This means there will be an imbalance, i.e. there will be more energy entering the system from the sun than there is energy leaving the earth’s climate system. To restore the energy imbalance the surface and lower atmosphere must warm.

None of this matters, what matters to the surface is the surface it radiates to, and that surface is very cold, find yourself a IR thermometer and measure straight up under clear skies. It’s pretty cold when it’s hot and humid (only ~60F colder on a mid 90’s muggy day, and tonight when it’s clear and cold out (~50F) it’s going to be close to -40F)

Without CO2 there would be a lot less water vapour. The warmists are right about that.

Except there no sign of an increasing trend in surface precipitation or humidity.

181. Henry says:
You honestly do not have not a clue…
And:
…perhaps you have a problem with the idea that everything goes according to a plan…
Henry, the ‘problem’ I have is being attacked by you, simply because we do not agree 100%.
Also, Henry, you wrote earlier:
There is no man made warming. If it is there it is so small that man cannot even measure it.
That’s exactly what I have been saying: AGW is too small to measure. That does not mean that AGW exists, or doesn’t exist. It means that if it exists, AGW is too small to measure. I am nothing if not consistent.
~the ostrich

182. richardscourtney says:

Greg Goodman:
At July 23, 2014 at 4:26 am you write

I think Lindzen & Choi 2011 is probably the most accurate assessment yet and it is the outlier.
They were so far off anyone else’s work that I originally dismissed their result. I suspect a lot of people , even being object, may have the same reaction but the more I actually do calculations and look at the evidence, the more I’m convinced that they are correct.

No. Lindzen & Choi were not “far off” from Idso.
In 1998 Idso had used a variety of methods which each provided a similar value for climate sensitivity to that later obtained in 2011 by Lindzen & Choi. Idso’s excellent paper can be read here
http://www.warwickhughes.com/papers/Idso_CR_1998.pdf
The common factor of the determinations of Idso with that of Lindzen & Choi is that they measured effects in the real world instead of constructing complex models.
Richard

183. John Finn says:

HenryP says:
Henry says
1) Some? 4 global data sets against how many you have that goes the other way?

UAH and GISS have do not have negative trends. In any case NONE of the trends are statistically significant. They are not even close to significance. In other words there is NO cooling.

2) I explained the sampling technique at the beginning of the tables =longitude does not matter as we are looking at the change in K/annum

It does matter. Tell us how you calculate the SH averages.

184. DavidR says:

“A new paper published in Ecological Modelling finds climate sensitivity to doubled CO2 concentrations is significantly lower than estimates from the IPCC and climate models…”
______________________
As the abstract of the paper states, the rate of 1.093 °C per decade is the ‘transient sensitivity’ or transient climate response (TCR). Equilibrium climate sensitivity (ECS) is given as 1.99°C. IPCC AR5 assesses ECS as likely to be 1.5°C to 4.5°C.
Therefore, contrary to the above comment, ECS given in this paper is within the ‘likely’ range as assessed by the latest IPCC report.

185. Steve Keohane says:

Mi Cro says:July 24, 2014 at 1:37 pm
John Finn commented
[…] ” Without CO2 there would be a lot less water vapour. The warmists are right about that.”
Except there no sign of an increasing trend in surface precipitation or humidity.

I agree and might go a further to say the RH trend is negative.
http://i61.tinypic.com/2wp16vt.jpg

186. richard verney says:

I am surprised by the debate between dbstealey and Henry P since this appears to be bluster about nothing.
Whilst my views are not important, I am more in the dbstealey camp, save that I accept AGW exists only to the extent that changes in land use affect climate on micro regional basis, eg., urbanisation, de-forestation, damming, large scale irrigation/farming practices.
As regards CO2 driven AGW, the jury is out; there is no convincing evidence that proves it, or disproves the existence of it.
I also have a slightly different view on its strength. What we can say, is the signal from CO2 driven AGW, if any, is so small that it cannot be detected by our best available and most sophisticated measuring devices. What does that mean? It means:
1. CO2 driven AGW may exist; or
2. CO2 driven AGW may not exist;
3. If the accuracy and precision of our measuring devices is small, the signal to CO2 driven AGW, if it exists is small at most (if it was large it would have been detected).
4. If the accuracy and precision of our measuring devices is large, the signal to CO2 driven AGW, if it exists may be large (of course in this scenario it could also be small).
So do we need to be concerned? There is only one scenario where there might be reason for some concern, and that is where the accuracy and precision of our measuring devices is large. In this scenario, we just do not know whether there is or is not a problem (and that is assuming that one is of the veiw that a relatively rapidly warming world is a problem – which in itself is another moot issue).
So it all boils down to, how large are the error bands in our best available measuring devices?
The warmists claim they are small, personally, I do not see the evidence for that, especially given the short time scale of the satellite data and ARGO buoy data.

187. richard verney says:

Further to my last post, one should not overlook the strong evidence that CO2 lags temperature on all timescales, and therefore CO2 is a response, not a driver.
That fact, if true, does not mean that CO2 cannot be a driver, but it does make it very much more difficult to detect an anthropogenic CO2 driven temperature response and signal.

188. @John Finn
Let me show you my results for Alaska.
http://oi40.tinypic.com/2ql5zq8.jpg
10 stations showed an average downward trend of -0.055K/annum since 1998.
That is almost one whole degree down since 1998.
However, I only used one of these 10 stations in my sample. It is because I figured out the correct sampling procedure. The problem with most other data sets is that they are not properly balanced.
a) The amount of weather stations taken from the NH must be equal to the amount weather stations taken from the SH
b) The sample must balance by latitude (as close to zero as possible)
c)The sample must also balance 70/30 in or at sea/ inland
d) longitude does not matter, as in the end we are looking at the change in average yearly temps. which includes the effect of seasonal shifts and irradiation + earth rotates once every 24 hours. So balancing on longitude is not required.
e) all continents included (unfortunately I could not get reliable daily data going back 38 years from Antarctica,so there always is this question mark about that, knowing that you never can get a “perfect” sample
f) I made a special provision for months with missing data, not to put in a long term average, as usual in stats, but to rather take the average of that particular month’s preceding year and year after. This is because we are studying the changing weather patterns over time.
As an example here you can see the annual average temperatures for New York JFK:
http://www.tutiempo.net/clima/New_York_Kennedy_International_Airport/744860.htm
You can copy and paste the results of the first 4 columns in excel.
Note that in this particular case you will have to go into the months of the years 2002 and 2005 to see in which months data are missing and from there apply the correction as indicated by me + determine the average temperature for 2002 and 2005 from all twelve months of the year.
So, John, what I am saying is that most other data sets are garbage, because they are in imbalance, mostly the NH stations are over-represented. You can clearly see from my tables that that leads to a skewed picture, i.e. more warming. Only my data set is properly balanced. But, as always, every person is entitled to cherish and hoard their own garbage.
Note that the proposed mechanism for AGW implies that more GHG would cause a delay in radiation being able to escape from earth, which then causes a delay in cooling, from earth to space, resulting in a warming effect. It followed naturally, that if more carbon dioxide (CO2) or more water (H2O) or more other GHG’s were to be blamed for extra warming we should see minimum temperatures (minima) rising faster, pushing up the average temperature (means) on earth. I found / you will find that if we take the speed of warming over the longest period (i.e. from 1973/1974) for which we have very reliable records, we find the results of the speed of warming, maxima : means: minima at 0.034 : 0.012 : 0.004 in degrees C/annum. That is ca. 8:3:1. So it was maxima pushing up minima and means and not the other way around. Anyone can duplicate this experiment and check this trend in their own backyard or at the weather station nearest to you. In addition, I find the following trends in minimum temperature records over time: 0.004K/annum (from 1974), 0.007K/annum (from 1980), 0.004K/annum (from 1990) and -0.009K/annum (from 2000). Putting these values out against the time periods indicated, i.e. 40, 34, 24 and 14 years respectively, you get the acceleration/deceleration of warming. I was astonished to find on a random sample of 54 stations, balanced as per procedure HenryP, an absolute perfect curve, a quadratic function, with Rsquare=1. That means 100% correlation. If there were any man made warming at all, one would expect to see some chaos in that curve…..(i.e. somewhat less than 100% correlation). Note that the theory of AGW implies rising minimum temperatures, pushing up the mean average temperature. See graph at just below the minima table!
There simply is no man made global warming. If it exists it is so small as to be immeasurable and it is inconsequential to what nature dishes out.

• HenryP commented
So, while you balance out based on selection of stations, I didn’t want to be accused of picking the station I wanted, so I broke the world up into smaller chunks, Continents, latitude bands, Bands 60 longitude degrees long, and the blocks (because they could be assembled into all of these with some work).
You’re free to download and use any of it, if you’d like, follow the url in my name.

189. ferdberple says:

74
Idso: A skeptic’s view of potential climate change
In addition, Ramanathan & Collins (1991), by the
use of their own natural experiments, have shown how
the warming-induced production of high-level clouds
over the equatorial oceans totally nullifies the green-
house effect of water vapor there, with high clouds
dramatically increasing from close to 0% coverage at
sea surface temperatures of 26°C to fully 30% cover-
age at 29°C (Kiehl 1994).
this sounds very much like what Willis has been saying in his articles in WUWT. that there is a dramatic increase in cloud cover in the tropics as temperatures climb past a certain threshold, that prevents warming past 30C.

190. @Micro
thanks.
You can chop it up like that, and [I think] that takes care of the 70/30 @sea/inland problem, but you must just make sure that your no. of nh stations = no. of sh stations and that total latitude (of all stations) balances out close to zero.
Longitude does not matter [in your sample] if you want to study a change in irradiation/temperature.
I see that the link to my tables in my comment to John Finn did not work
here it is
http://blogs.24.com/henryp/files/2013/02/henryspooltableNEWa.pdf
@dbstealey
you are sitting on the fence, and you like it there.
It is OK, for me, if you are comfortable there, and happy,
but to me it is not the same as being truthful and obedient to the Truth.

191. mpainter says:

DBStealy:I do not understand why AGW would not qualify as a hypothesis. It puts warming attributable to increasing atm CO2 and predicts increasing temperatures with increasing CO2. This has not happened and thus the Hypothesis stands refuted by the data, it seems.

192. richard verney says:

mpainter says:
July 25, 2014 at 9:55 am
///////////////
Because, that alone does not establish that CO2 is the driver of temperatures..
It would be possible that something, other than CO2, could be driving temperatures up. As a consequence of the warmer temperatures (which were not driven up by CO2), more CO2 is out gassed thereby increasing the concentration of CO2 in the atmosphere.. So you can have correlation, but correlation is not causation.
AGW is presently just conjecture. Of course, that does not mean that it does not exist, and is not real. It may be real.
As you say, the fact that temperatures are not increasing runs contrary to the ‘theory’ (conjecture), but the problem is the accuracy of the data sets, and whether there is an AGW signal in those data sets, albeit weaker than the error bands of the data sets that we are using.
See more generally my recent posts above.

193. richard verney says:

HenryP says:
July 25, 2014 at 7:02 am
/////////
Henry
I like all the work that you have done with the compilation of your tables. I consider that you are right to look at both maxima and minima seperately. I hate averages, since it disguises the detail, and the devil lies in the detail. It has always surprised me that there is not much more detailed analysis of max/min temperatures seperately, analysis of seasonal data etc etc.
I myself do not consider a few tenths of a degree to be climate change. So what are we saying that is climate change, eg., generally the nights are a little bit warmer, Spring starts a couple of days earlier, Autumn starts a couple of days later, winters are less harsh, high latitues are warmer but the tropics are not etc. etc. If one is discussing climate change, I would expect to see a detailed analysis iofthe ways in which climate (not temperature) is changing. Strange that we do not see that kind of approach, but then again, ikt would demonstarte that climate is local/regional, not global and would be more difficult to run ‘we are all in it together’ argument..
That said, for reasons detailed in my post at 3:50 am, I think that you are overplaying your hand. If for no other reason than the real issue, is energy imbalance, and looking at temperatures (other than sea temperature) is not measuring the required metric, and that dbstealey is right to not go quite as far as you go. But it appears to me that the difference between you is so small, so there appears nothing in substance in the argument and the allegations of fence sitting.
At some stage the science will come out, and people will be able to firm up their views. Presently, the data sets are so poor, with wide error bands, and not fit for the purpose that they are being put, people are over extrapolating the data etc such that, in my opinion, no fiirm conclusion can rightly be reached, at this stage. Time will tell whether you are right.
Continue your good work. I check you pool table from time to time, and no doubt many others do as well.

194. @Richard
Thanks. The drop in global temp. is now about -0.2K since 2000 according to my own data set (means).
It does not look like a lot, agreed. My wife also still laughs at me worrying about it.
However, clearly the graphs are still pointing to more that is coming up. We are cooling from the top latitudes down,
e.g. like I said
However, a small change may add up to more, e.g. -0.2K means more cloud formation at lower latitudes, and less clouds at the higher latitudes (droughts) ,then more clouds at lower latitudes mean more cooling, etc. etc. We spiral down.
All of this while everybody is scrambling to explain the pause, using useless data sets that are not [even] properly balanced.
My results in the tables have revealed to me where we we are in the 87 year Gleissberg cycle,
http://www.nonlin-processes-geophys.net/17/585/2010/npg-17-585-2010.html
[I am not yet sure from my own results where we are in the De Vries cycle]
According to my various calculations, comparatively speaking, we are now in ca. 1925.
Note that the Dust Bowl drought 1932-1939 was one of the worst environmental disasters of the Twentieth Century anywhere in the world. Three million people left their farms on the Great Plains during the drought and half a million migrated to other states, almost all to the West. http://www.ldeo.columbia.edu/res/div/ocp/drought/dust_storms.shtml
I find that as we are moving back, up, from the deep end of the 87 year sine wave, there will be standstill in the change of the speed of cooling, neither accelerating nor decelerating, on the bottom of the wave; therefore naturally, there will also be a lull in pressure difference at that > [40 latitude], where the Dust Bowl drought took place, meaning: less weather (read: rain). As stated before, according to my calculations, this will start around 2020 or 2021…..i.e. 1927=2016 (projected, by myself and the planets…)> add 5 years and we are in 2021.
Danger from global cooling is documented and provable. It looks we have only ca. 7 “fat” years left……
WHAT MUST WE DO?
We urgently need to develop and encourage more agriculture at lower latitudes, like in Africa and/or South America. This is where we can expect to find warmth and more rain during a global cooling period.
We need to warn the farmers living at the higher latitudes (>40) who already suffered poor crops due to the droughts that things are not going to get better there for the next few decades. It will only get worse as time goes by.
We also have to provide more protection against more precipitation at certain places of lower latitudes (FLOODS!), <[30] latitude, especially around the equator.

195. MPainter says:
I do not understand why AGW would not qualify as a hypothesis. It puts warming attributable to increasing atm CO2 and predicts increasing temperatures with increasing CO2. This has not happened and thus the Hypothesis stands refuted by the data, it seems.
That is my point. To be elevated from a conjecture to a hypothesis, the CO2=AGW claim must be able to make repeated, accurate predictions. CO2=AGW does not. For example, as CO2 continues to rise, global T does not follow, which was predicted incessantly by the alarmist crowd [until global warming stopped].
Next, if you want to call AGW a hypothesis, that’s OK. But a conjecture is not wrong per se. A conjecture is the starting point of the scientific method [Conjecture, Hypothesis, Theory, Law]. For myself, until/unless I have testable measurements quantifying the fraction of a degree of global warming attributable to human CO2 emissions, I will consider AGW to be a conjecture.; an unproven supposition.
Some folks, like the ‘Slayers’, claim that the Greenhouse Effect doesn’t exist, and there are those who say it is all due to the Sun. There are others who say it is all due to natural cycles. At this point, we just do not know. But I personally don’t see any evidence that anthropogenic CO2 causes any measurable global warming, because there are no such measurements. Many people have been searching for AGW measurements for more than 30 years, but with no success at all.
I certainly don’t know what drives global climate changes. But I want to know. If the answer turns out to be CO2, then I will accept that — so long as it is proven with testrable measurements. Because the goal is scientific knowledge, not being part of a ‘consensus’.