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Professor Lindzen’s ‘Mea Culpa’ – Backs Away from Greenhouse Gas Theory

Written by John O'Sullivan

World leading climate expert Richard Lindzen admits existence of compelling evidence discrediting mainstream greenhouse gas theory (GHE) of man-made global warming; apologizes for emphasis on carbon dioxide. The focus on CO2 since the 1980’s was due to politics, not science.

In a step back from consensus thinking Professor Lindzen declares, “leading figures in atmospheric physics from the mid-1950’s to at least the early 1980’s, clearly did not emphasize greenhouse warming.”

Dr Lindzen joins the growing ranks of prominent scientists prepared to defy the crumbling mainstream “settled science” that wrongly characterizes earth as a ‘greenhouse.’

The ‘greenhouse gas’ scare story was successfully sold to the public and centers around carbon dioxide – a benign trace gas essential to plant growth. In the 1980’s it became the dominant factor in a concocted dangerous ‘climate forcing’ (CO2 sensitivity) metric conceived in the mind of former top NASA climate scientist, Dr James Hansen.

Hansen succeeded in orchestrating a pseudo-scientific narrative that this trace gas had been widely accepted to be the climate’s control knob for over a century. But as another decade passes without dramatic rises in temperature, despite CO2 levels still rising,  Hansen’s back story – along with his ‘CO2 sensitivity’ metric –  is being recognized as a fiction.Professor Richard Lindzen, who has published more than 200 scientific papers and books makes his  mea culpa in co2coalition.org’s  ‘Global warming: The science in three nut shells’. The telling evidence Lindzen points to is shown below.

Lindzen, the Alfred P. Sloan Professor of Meteorology at the Massachusetts Institute of Technology (MIT), writes:

“Figure 4.1 [above] is the cover page of an important volume from 1955. The portrait is of John von Neumann. As the head of the Institute for Advanced Study in Princeton, he formed the first group to undertake the numerical prediction of weather…. Only one article dealt with radiative transfer, and it did not focus on the greenhouse effect, though increasing CO2 was briefly mentioned. The contributors were the leading figures in atmospheric physics from the mid-1950’s at least the early 1980’s, and they clearly did not emphasize greenhouse warming.”

John von Neumann stressed the core mechanism of climate to be “hydrodynamical theory” (p. 10). Back then the water cycle, convection and conduction rather than radiation and CO2 were the talking points among the scientific elite. Inexplicably, there exists nothing in the modern scientific literature since that era showing any scientific reason why the climate science community en masse switched focus to the now discredited CO2 forcing hypothesis.

Lindzen concedes:

“…climate is a remarkably complex system that cannot be reduced to a CO2 knob, something you turn up or down like your house thermostat, to control global temperature.”

Indeed Canadian professor Dr Tim Ball, another popular international climate expert, noted:

“The concept of climate sensitivity was first derived, as with so much done on climate, to overcome a perception problem not a scientific one. Who did the actual calculations of climate sensitivity is not documented to my knowledge. The earliest paper I have is the 1984 paper by James Hansen and Takahashi referenced in this paper.”

Like Richard Lindzen (77), 79-year-old climatologist Tim Ball is a time-served veteran in the climate wars. Both researchers are keenly aware that until the 1980’s, when global warming came to the fore, it was global cooling that was the big talking point. The historic scientific evidence is compelling that the leading scientific institutions worked with governments to address the global cooling (not CO2) threat.

Negative evidence comes from American Meteorological Association, UK’s Met Office and CIA. It supports a wholly different narrative than the one sold to the public for a generation. It suggests carbon dioxide and the once-abandoned greenhouse effect was likely hyped from the late 1970’s for political reasons rather than scientific.

Professor Lindzen is highly regarded among skeptics and pioneered his own climate ‘Iris theory’ about changes in cloud cover.

Lindzen’s  “iris hypothesis” (Lindzen et al., 2001) tells us that, firstly, in a warmer climate, enhanced precipitation efficiency will lead to less cloud being detrained into the troposphere from convection. Secondly, we see with less cloud cover, more infrared radiation can escape to space. This thereby creates a strong climate-stabilizing negative cloud feedback that prevents significant warming from any increase from supposed ‘greenhouse gases.’

Staunch defenders of the greenhouse gas theory have tried to discredit Lindzen work but as Dr Judith Curry writes, they seem to have failed.

On that basis it seems logically consistent for him to walk back from the consensus theory that carbon dioxide and a radiation-focused mechanism dominate our climate system.

Making a direct attack on the accepted (and concocted) historical narrative Lindzen explains:

“A standard part of these narratives is that the greenhouse effect has been known since the work of John Tyndall in the nineteenth century, with additional references to Svante Arrhenius and Guy Stewart Callendar. The clear implication is that the zero-dimensional approach had always been accepted as the fundamental approach to climate, and, more importantly, to climate change. This is, however, far from true.”

Since around 2010 more researchers have found more emphasis should have been placed by climate science on the impacts of the water cycle. It is argued that evaporation, condensation, convection and conduction are more dominant forces than radiation.

Such scientists have struggled to get their theories published in mainstream journals and have chosen to  promote their findings in less conventional forums such as Principia Scientific International (PSI). Scientists at PSI were among the first to welcome Henrik Svensmark’s idea that cosmic ray impacts clouds, as confirmed in a groundbreaking experiment at CERN.

It is also probably worth noting that during the ‘60’s and ‘70’s when global cooling was the focus of climate alarm, the popular climate model was the Budyko-Sellers model that emphasized the role of equator-to-pole heat transport in enabling the possibility of an ice-covered earth. Back then very few scientists linked CO2 with climate change. NOWHERE in the Budyko-Sellers model is any importance (or even mention!) given to carbon dioxide or the GHE.

There are other important documents from the 1950’s to the 1970’s that are compelling proof that the greenhouse gas theory was DISMISSED as a possible theory of climate. Among them was a key CIA report:  ‘A Study of Climatological Research as it Pertains to Intelligence Problems’ (August 1974).The CIA climate report did not make mention AT ALL of any greenhouse gas effect because it wasn’t regarded as credible.

We know the GHE was not regarded as credible from at least 1950. This is thanks to the work of one of the foremost climate scientist of his day,C.E.P. Brookes. Brookes was head of Britain’s prestigious Meteorological Office. Brookes said this about the GHE:

“it was never widely accepted and was abandoned when it was found that all the long-wave radiation [that would be] absorbed by CO2 is [already] absorbed by water vapor.”[1]

Therefore, it is little wonder than Lindzen now writes:

“ [we] have focused on the greenhouse picture despite the fact that this is probably not the major factor in climate change. That is to say, we have accepted the basic premise of the first [dominant] narrative. Mea culpa.”

Lindzen explains that the radiative CO2 narratives of greenhouse warming, “leads to a view of climate sensitivity that bears little resemblance to past climate change.” Lindzen now joins esteemed fellow American climate professor, Fred Singer (92), who announced his step away from the GHE mainstream  in 2015 when he announced:

“I should note that I am somewhat out of step here with my fellow skeptics. Few of them would agree with me that the climate sensitivity (CS) is indeed close to zero. I will have to publish the analyses to prove my point and try to convince them. Of course, nothing, no set of facts, will ever convince the confirmed climate alarmists.”

It is no coincidence that it is mainly the retired scientist, or those near retirement – after long and successful careers – who are proving the most willing to speak out against the consensus obsession on CO2.


[1]  C.E.P Brooks, “Geological and Historical Aspects of Climatic Change.” In Compendium of Meteorology, edited by Thomas F. Malone, pp. 1004-18 (at 1016). Boston: American Meteorological Association (1951).

Comments (6)

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    Lindzen is making a joke when he says “mea culpa”. He has always been amongst the very strongest, if not the strongest, well qualified and knowledgable opponent of the dangerous CO2 warming dogma. His joke means that he has allowed himself to be lured into wasting his time thinking about many ways of refuting and debunking the dogma, instead of doing other more useful things, such as studying more interesting and useful aspects of meteorology and climatology. He has been amongst the most effective truly scientific and adequately informed refuters and debunkers of the dogma. It is not sensible to interpret his joke as him recently backing away from the mainstream. He has always, for decades, been away from the mainstream, just further away and more sceptical and less alarmist than some other sceptics.

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      Richard S Lindzen and Kerry A Emanuel produce 5 pages of scientific analysis of the greenhouse effect which is exactly the same as all of the rest of the hypotheses.

      “Next to water in all its phases, the important green￾house substances in the atmosphere include carbon dioxide, methane, nitrous oxide, ozone, and various chlorofluorocarbons (CFCs).”

      “Incoming solar radiation is absorbed at the surface, which, in the absence of an atmosphere, would have an equilibrium tempera￾ture Te. Infrared radiation emitted by the surface is absorbed by the atmosphere, whose temperature is Ta. The atmosphere in turn radiates infrared radiation both upward to space and downward to the surface. Ta = Ts = 21/4T”

      “At the top of the atmosphere, the total outgoing radiative flux, given by oTa4 , must balance the net incoming so￾lar flux of 240 Wm”2 , giving Ta = 255 kelvins. But the surface receives energy from both the sun and the atmosphere, and the thermal equilibrium of the surface re￾quires that aT\ = 240 Wm~2 + o-Ti = 480 Wm~2”

      “The model of the greenhouse effect illustrated by Figure 1 is obviously a gross oversimplification. To perform an accurate estimate of the greenhouse effect, we have to divide the atmosphere into many layers, each with its own temperature and each radiating only a fraction of what the Stefan-Boltzmann law gives (this fraction is called the emissivity). This fraction depends crucially on the amount of greenhouse gases and clouds in the layer, and it determines not only how much radiation the layer can emit but also what fraction of the radiation passing through it from other layers can be absorbed. We also have to take into account that the atmosphere is not completely transparent to sunlight; clouds and water vapor absorb some of the incoming solar radiation. When all these things are accounted for in sophisticated radiative transfer models, the equilibrium surface temperature works out to be about 350 kelvins or about 80°C.”

      “The greenhouse effect is so large that, in the absence of other processes, it would make the surface of the Earth very hot indeed.”

      And he claims to be a sceptic.

      How does he explain the maximum temperature on the Moon ?

  • Avatar

    Jim McGinn


    The biggest and longest standing lies in regard to the atmosphere have nohting to do with CO2 and have everything to do with H2O. Conservatives are on the wrong side of this issue:

    Sometimes people believe things that are nonsense because they have painted themselves into a corner with their assumptions and believing in nonsense is the only option that remains to save them from appearing to be complete fools. The most stupefying myth in all of meteorology is the myth that steam can persist in our atmosphere.
    The ‘Missing Link’ of Meteorology’s Theory of Storms

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    Ronald Chappell


    Of course the hydrodynamic cycle is key to the earth temperature control. Aside from the perhaps 16% of IR direct to space thru the 8-12 u window, there is no significant physics available to cool the earth other than the “greenhouse” gases, CO2 (~10 %) and Water (vapor, cloud, ice , the remaining ~74%) regardless of the difficulty of enumerating the complex random chaotic hydrodynamic cycle, there is no other gas of consequence to do the cooling to balance of the input power. It is then determined by default to be the NET AVERAGE coolant. It cannot be a net warming green house effect gas even if there is conjecture of its increase due to slight absolute humidity increase due to CO2 GH warming. The water cycle does the major cooling, How could anyone construe a slight increase , ~<1% to have a net warming effect when the WV does ~74% of the cooling.
    When the double CO2 density looses ~2 watts radiation effectiveness due to its reduced effective radiation altitude (Harvard HITRAN IR spectral radiation change), water must make up for this loss as the earth/atmosphere accumulates energy from the constant solar input to raise its temperature by 0.5 C.
    End of story; stable adjustment, no positive feedback is evident or possible. There is indeed no additional energy into the system (2x CO2 only) to evaporate additional water.
    In the case of Solar/CME additional energy into the system, additional water can be evaporated and thus a feedback effect +or- may ensue. As is evident from the above, this feedback is net negative since additional hydrodynamic activity is the only cooling agent of important magnitude.
    Lets hear no more of positive water vapor feedback and use of the electronic feedback amplifier equation to compute increases in temperature. This equation represents a system in which an input is amplified by a device which taps an independent (regulated to behave as infinite) power source and a physical mechanism to feed back some of this new energy back to the input. None of this is available in the atmosphere and does not in any way emulate, simulate or represent the atmospheric physics. It cannot 'tap' the surface energy to power this imagined amplification. The constant power available from the surface as received from the sun is the 'signal' to be amplified in this scenario. To "pull" any additional energy from the earth in the amplification scenario would cool the signal of every watt that the imagined amplifier is trying to add to the output. This sounds nonsensical as it is. It is a zero sum game and cannot exist.
    Thank you for your attention, all comments are of course welcome. A more complete write up is available upon request with email return address.

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    “Since around 2010 more researchers have found more emphasis should have been placed by climate science on the impacts of the water cycle. It is argued that evaporation, condensation, convection and conduction are more dominant forces than radiation.”

    However my take is….since around 2010 more politicians and their aides have found more emphasis WAS placed by climate science on the impacts of the emissions. Therefore the narrative of GGE and CO2 and EMISSIONS reigned on and hence all the exorbitant green alternatives and policy to lower emissions (whatever those are).

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    Joseph A Olson


    I witnessed the Lindzen-North debates at Houston Petroleum Club and at Rice University, confirming the rigged three sided climate debate, between Alarmist, Luke Warmists and the correct NO Warmists. I wrote….

    “No Loophole for Your Soul” at CanadaFreePress, January 2010

    Thankfully, the phantom ‘back radiation warming’ force is finally losing it’death grip.

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