Thursday, December 19, 2013

Observations show IPCC exaggerates anthropogenic global warming by a factor of 7

A compilation of at least 30 published studies based upon satellite and ocean observations demonstrate climate sensitivity to a doubling of CO2 levels after all feedbacks is only about 0.5 C, which is ~7 times less than the 3.2C claimed by the IPCC AR5 modelled mean estimate.

Note: If the current rate of increase of 2 ppm/yr continues, CO2 concentrations would require about 200 years to double. These climate sensitivity estimates also assume the temperature increase was solely due to greenhouse gases and do not include natural influences from solar amplification, global brightening, ocean oscillations, etc. which can alone account for 95% of climate change over the past 400 years.

30 published peer-reviewed studies and 5 unpublished low estimates of climate sensitivity [updated]:

Lindzen & Choi [2011]: 0.7 C

Spencer & Braswell: 0.62 C

Bjornbom: 0.67 C

Eschenbach: 0.2 C 

Levitus 2012 = 0.39 C

Douglass & Knox [2012]: 0.16 * 1.3 = 0.21 C

Lindzen & Giannitsis: 0.67 C

Douglass et al [2005]: .22 * 1.3 = 0.29 C

Bogdanov: .41*1.3 = 0.53 C

Chylek: .385*1.3 = 0.50 C

Monckton: .12 * 3.7 * 1.3 = 0.58 C

Paltridge: .1 - .3 (based on NCEP trends, figure 10) (ave .2)*1.3 = 0.26 C

Schwartz: 0.3 * 1.3 = 0.39 C


Bengtsson: 2C with lower bound 1.167C

The Hockey Schtick: 0.28C [to doubling of man-made CO2 emissions]

The Hockey Schtick [alternate method]: 0.25C [to doubling of CO2 levels]

Harde: 0.43C

Norden: 0.8 C

Lewis & Curry: 1.3C Transient Climate Sensitivity, 1.6C Equilibrium Climate Sensitivity

Irvine: 1.3C

Cederlöf: 0.32C mean, [0.23C to 0.32C range]

McLean: CO2 played little if any role in post-1950 warming, i.e. sensitivity << 1C

Skeie: 1.8C

LaTour: -0.12C

Brown: 2.62*log(2) = 0.79C

Schwartz: 2C [mean estimate]

All very similar [except Bengtsson at 2C, and Lewis & Curry at 1.6C, Skeie at 1.8C, Schwartz at 2C, but still significantly lower than IPCC AR5 mid-range modeled estimate of 3.2C] and averaging out to about 0.5 C climate sensitivity to a doubling of CO2 levels

Note: Equilibrium climate sensitivity [ECS] at the top of the atmosphere [TOA] has been determined from the above analyses assuming ECS is 130% of transient climate sensitivity [TCS] per Otto et al. 

UPDATE: Thanks to a comment below from 

Kenneth RichardSeptember 22, 2014 at 9:27 PM

Here are a few more not included on the list: ---> +0.00 C ---> +0.02 C ---> +0.4 C ---> +0.51 C ----> +0.96 C ----> +1.1 C ----> +1.3 C ---> +1.35 C ---> +1.6 C



  2. Hockey schtick,
    I would be interested in your opinion on this critique of the Paltridge et al paper

  3. another low sensitivity estimate:

  4. Why is Bentgsson listed here at 0.54C but on an earlier page,, listed at 2C with a lower bound of 1.167C?

    1. Ah, good point, you are correct & this post corrected

  5. Here are a few more not included on the list. ---> +0.00 C ---> +0.02 C ---> +0.4 C ---> +0.51 C ----> +0.96 C ----> +1.1 C ----> +1.3 C ---> +1.35 C ---> +1.6 C

  6. Human sensitivity is .0004C/ppm. If "doubling" is considered to be 700 ppm then it would be 420 ppm (120+300) x .0004 = .168C. Pretty much with Willis.

  7. The Hockey Stick alternate method to compute climate sensitivity

    Warmists including Andy Lacis and Gavin Schmidt claim that “Prior to the increase in anthropogenic CO2, the atmospheric CO2 concentration was about 280 ppm. This would contribute a radiative forcing of about 30Wm-2, so about 20% of the overall [33K] greenhouse effect.”

    Taking this assumption at face value, in 1850 CO2 was responsible for about 6.44C warming above 255K equilibrium temperature [32.2C * 0.2], and CO2 responsible for about 6.6C warming now [33C * 0.2], since the globe has only warmed 0.7 to 0.8C since 1850. Thus, a ~43% increase in CO2 allegedly responsible for 0.16C warming, about 12 times less than claimed.

    0.16C/ln(1.43) = .45

    .45*ln(2) = .311 W/m2

    .311 W/m2/[3C/3.7W/m2] = 0.25 C warming per doubling of CO2 levels

  8. Paper finds ECS 1.8 °C

  9. Otto et al finds ECS based on 1970-2009 of 1.9C

  10. Climate sensitivity ~1.6C

    p 23

  11. From my comment at ATTP's blog

    ATTP says "We’re confident that 3.7Wm-2 will produce 1 degree of warming. Anthropogenic forcings are about 2Wm-2 today, so are associated with around 0.5 – 0.6 degrees of warming. If you’ve read some of the comments, you’ll note that the greenhouse effect is consistent with an ECS of 3 degrees. Hence, it is maybe a little surprising that we’ve only warmed by around 0.9 degrees. However, we haven’t reached equilibrium, so it’s not inconsistent.”

    Per Otto et al, ECS is only about 1.3*TCR, thus as stated above, “in 1850 CO2 was responsible for about 6.44C warming above 255K equilibrium temperature [32.2C * 0.2], and CO2 responsible for about 6.6C warming now [33C * 0.2]. Thus, a ~43% increase in CO2 allegedly responsible for 0.16C warming, about a order of magnitude less than claimed.” from which can be derived using the conventional assumptions that TCR is 0.25C to a doubling of CO2 levels, and per Otto et al, ECS would thus be about ~ 1.3*0.25 = 0.325C

    ATTP says “We’re confident that 3.7Wm-2 will produce 1 degree of warming.”

    Assuming this is true, for the 33K GHE, 33*3.7W/m2 = 122.1 W/m2 total greenhouse forcing, of which you said 30W/m2 is from CO2, so 30/122.1 = 25% of the 33K GHE from CO2 alone, even more than the 20% stated above. Using 25% instead of 20% in the above calculation has the effect of reducing TCR to 0.19C to a doubling of CO2 levels, and per Otto et al, ECS would thus be about ~ 1.3*0.19 = 0.25C

  12. There is no valid physics which can be used to prove that there is any sensitivity at all to carbon dioxide other than a total cooling effect less than 01. degree. Below is my email today (15 October) to Australian politicians headed ...

    Proposed High Court Challenge - Empirical evidence proves Greenhouse conjecture WRONG - CO2 cools.‏

    Dear PM and other Politicians, Climate Council and Alan Jones

    As I have previously written, the Australian Government has failed to pay due diligence in studying what is a completely false claim that carbon dioxide supposedly warms Earth's surface. In that the Dept of Environment has not investigated the very valid physics which I present, nor even asked any physicist to contact me or discuss the matter, I propose soon to place a display advertisement in "The Australian" newspaper calling for funding from large companies who will be adversely affected by carbon trading in order to pursue legal advice pertaining to a possible High Court challenge against the Government. In the meantime I would suggest you heed this brief outline and perhaps read my book, copies of which have been sent to some of you. I write based on very extensive research over recent years and experience in physics dating from the 1960's when I won a university scholarship and got my first degree in such. I suggest an enquiry should be initiated and I am happy to attend gratis.

    The physics in my book "Why It's Not Carbon Dioxide After All" and my peer-reviewed paper "Radiated Energy and the Second Law of Thermodynamics" has been proven correct by empirical evidence. See my site:

    As Judith Curry wrote on her blog today “Climate models diminish the importance of actually reasoning about diverse types of evidence.”

    Real world temperature data proves beyond doubt that the most prevalent greenhouse gas, water vapor, causes mean daily maximum and minimum temperatures to be lower because its radiating properties work against the gravitationally-induced temperature gradient in the troposphere. This lowers the gradient and thus lowers the supporting temperature by about 10 to 12 degrees, as is confirmed by empirical evidence. Further evidence from other planets reinforces what I say. Because of this it is blatantly obvious to all those who are not gullible and understand thermodynamics that the greenhouse conjecture is totally false and carbon dioxide, like water vapor, actually cools, but only very slightly, perhaps less than 0.1 degree.

  13. (continued)

    Climate models disregard the gravitationally induced temperature gradient and assume it doesn't exist, despite the science first presented by the brilliant 19th century physicist, Josef Loschmidt who was first to estimate the size of air molecules. The models also assume that the radiation from the cold atmosphere delivers nearly twice as much thermal energy to the surface as does the Sun. It doesn't, and that's why you don't feel it at night. They also disregard the obvious fact that nearly all the Sun's radiation passes down into the first 20 metres or so of the ocean, where it's colder. There can be no heat transfer from such colder depths in the ocean thermocline back up to the thin surface layer in the non-polar regions, and so that energy only eventually warms the polar surfaces. So the calculations which use all the radiation from the Sun and the atmosphere, added together and used in the Stefan-Boltzmann equation to "explain" the surface temperature are completely false. What does happen is explained in my book, and the mechanism therein can be used to calculate the temperature on Venus and even at the base of the nominal troposphere of Uranus, where it's hotter than Earth's surface even though the planet is 30 times further from the Sun. That temperature has nothing to do with direct radiation from the Sun.

    All climate follows natural cycles which are very evident in the inverted plot of the scalar sum of the angular momentum of the Sun and all the planets. In that plot (calculated from planetary orbits) we can predict slight cooling till 2028, then 30 years of warming (by about half a degree) and then 500 years of long-term cooling with superimposed 60 year cycles. This plot (below) has been on my website for three years.

    The above is fact. Give it your earnest consideration and feel free to discuss it with me on 02 98.........


    Doug Cotton

    PS In 7 months since my book was published there is still no claim made for the $5,000 reward to prove the content substantially wrong.