How sensitive is the climate to greenhouse gases?

Nicholas Lewis gave a keynote lecture with the Title “How sensitive is the climate to greenhouse gases?” – Is it really necessary to reach zero emissions in 2050? At our “Ontgroeningsdag” event on 7 March 2019 in Amsterdam. Video follows.

177 thoughts on “How sensitive is the climate to greenhouse gases?

  1. Loss of arctic sea ice isnt a +ve feedback. At the angle sunlight strikes the arctic ocean at water is fairly reflective. Plus the loss of ice cap allows the ocean to lose heat. And in June the arctic is quite cloudy, so not much sunlight hits the surface anyway

      • Yep.

        Oh, but the albedo of ice is high so it must be that open water warms up (no, ‘heats up’) during the winter while arctic sea ice is a cooling feedback.

        • Ya know …. I actually think arctic sea ice is feedback that warms … I guess you could say, a negative feedback to cooling. As the ice grows, it insulates the ocean from losing heat. As it melts, it allows cooling. When I say cooling, I mean it allows heat transported from lower last to escape to the colder air above.

          As I’ve said before, compare the correlations of CO2, Solar, and SST with Atmospheric temperature, and you’ll find only one is a near perfect fit, … the correlation between SST and Atmospheric temperature. The so called climate scientist are looking in the wrong place. They shouldn’t be looking to see what warms the atmosphere, they need to be seeking to understand what controls SST. ….. which is the interface between the gigantic capacitor known as the ocean and the air above.

          • I think this is exactly right. It plays out as a cycle with open Arctic waters correlating with higher atmospheric temperatures in the |northern hemisphere while the Arctic ocean cools and more ice cover correlating with lower atmospheric temps in the |Northern Hemisphere while the Arctic ocean slowly builds up heat. The higher albedo delays the eventual tipping point to melting of the ice while the higher absorption during low ice conditions delays the eventual onset of ice expansion.
            We are now in the satellite era and able to see this for the first time. Unfortunately, a cartel of illegitimate pseudo scientists and Lefty politicians ( Gore) got out in front of this with a political agenda.

    • Doesn’t the addition of freshwater to the sea cause cooling? So there is some negative feedback from melting ice. Not sure how to quantify it or how much it is offset by albedo changes, but just saying.

      “Around 9,300 years ago, a glacial dam burst at the southeastern end of Lake Superior, provoking pervasive Northern Hemisphere cooling, followed by a minor meltwater pulse about 9,000 years ago”

      • That article contains many statements which are just not true. NASA, I am surprised.

        Who’s in charge of that organisation, anyway?

        • Remember the NASA Muslim Outreach Program? Who needs facts when there’s money to spend and minds to control?

          • Yes, one cannot say, pretending to know from first principles, that CO2 itself has a so-called Forcing of 4 W/M/squared. This is based on the assumption that all so-called warming, from 1850 or so, whether or not we have any sort of world-wide data concerning world-wide temperatures, which we do NOT, shows a forcing.

            Apparently he must say this to remain on the TEAM. His comments combine provable statements from first principles, with other comments which are NOT.

            Is it Oxford or Cambridge? Seem to remember that it is Cambridge. His professors would be ashamed if they passed him…

    • Would you care to explain how come that as of this week there is some 14.5 million Km2 of ice in the Arctic basin, with the Danish DMI indicating 5-8 ft thickness?
      That’s enough to cover all of Canada and 50% of the US in some 6 ft of ice.

      At the late September minimum last year, there was enough ice to cover some 75% of Australia.

      Loss, to paraphrase Einstein, is clearly relative.

  2. To all our anti-climate-craziness-warriors, like Nic and Anthony, keep it up, please. I have the will-power yo read and vocally support but not the energy to do what you all are doing. Want a prophecy?

    There will be titles and awards named after you guys in your fight against hysteria, as well as there should be negatitve awards named after the list of worst alarmists.

  3. The correct answer:
    Climate sensitivity to CO2 is unknown.

    No One Knows.

    Unfortunately. almost no one
    will accept “No One Knows”,
    so you have to give them
    some kind of number.

    The number could be an
    extrapolation of past
    global warming, and CO2 level
    growth, because there is no
    logical reason for wild guessing
    a future warming rate that is different
    from the past warming rate.

    I know the climate computer games have been
    forecasting a “different” future global
    warming rate for the past 30 years, and they
    have been wrong for the past 30 years,
    forecasting an average of triple the
    warming that actually happened.

    I’m excluding the Russian climate model
    from the average climate model,
    because it is obviously
    colluding with Donald Trump,
    and can’t be trusted !

    The average temperature,
    per UAH satellite data,
    ended 2018 at the same
    level as the 2003 peak.

    Maybe after 15 years
    of no temperature change,
    the obvious conclusion is
    the average temperature
    has NO sensitivity to
    greenhouse gases,
    or the sensitivity
    is too small to measure?

    Also, CO2 levels have been
    going up since 1940.

    We’ve had global cooling
    (1940 to 1975),
    and we’ve had global warming
    (1975 to 2003),
    and we’ve had no change
    (2003 through end of 2018).

    Which trend is the “right” one?

    The Vostok ice core studies
    tell us CO2 levels are the RESULT
    of ocean warming and cooling
    from natural causes.

    There’s very little evidence that CO2
    “controls” the climate.

    Even if ALL the warming since 1950
    is blamed on CO2, and only CO2,
    the rate of warming since 1950 has been
    mild and harmless — equivalent to
    a +1 degree C. TCS
    — and suggesting
    a worst case of +2 degrees C.
    of global warming
    in the next 200 years,
    if CO2 levels keep growing
    at +2ppm per year
    = ho hum.

    My climate science blog:

    • No one knows the climate sensitivity because it doesn’t exist. Sure; CO2 absorbs IR but it collides with N2 and O2 in pico seconds, much faster than it can reemit. Hot air rises. Convection is key to this whole thing. If that wasn’t true, then the released latent heat (before condensation from the 86.4W/m^2 from evapotranspiration ) would boil our oceans.

      Clouds vs no clouds represent temperature differences as much as 11C. The IR that hits the low lying clouds is reflected and that DWIR is much stronger than any DWIR that comes from re emission. Stronger in 3 ways. 1) Reflected IR is stronger than absorbed and reemitted IR and 2) The albedo effect from low hanging clouds is as much as 70- 90% 3) Average cloud cover ~ 60%. Average cloud cover in the arctic ~ 70% whereas over the South Pole it is ~ 3%. Over the period 1970 to 2001, Antarctica decreased in temperature and over the last 60 years of mesuring temperatures in the South Pole; there hasnt been any net warming.

      Since the atmospheric window only represents about 10 to 25 % of the total upward IR, then the rest is absorbed/reflected by either clouds, water vapour, or CO2. Clouds are responsible for 85% of the warming from DWIR.

  4. “How sensitive is the climate to greenhouse gases?”

    How ’bout ZERO!!!

    1) Atmosphere cools the earth.
    2) BB radiation from surface is not possible.
    3) GHG get no energy to loop.

    1 + 2 + 3 = 0

    • I think you’re right – zero. Based on emissivity and absorption of CO2 at a given partial pressure, it’s specific gravity, and it’s ‘mixing’ being a function or both spatial and temporal scale, I think it’s a big fat zero.

      The question that’s more reflective of our understanding of physical chemistry is: how sensitive are carbon-based molecules to temperature?

      • No the question is, “How sensitive are the egos of alarmistas to the realization that their physics might be wrong?”

        I’ve never bought into the idea that the gap in the spectrum represents any actual “blocking” or “slowing” or obstruction of radiation of any kind. It represents the nature of CO2 to absorb AND to emit in a particular range — like a particular rhythm that has a particular character that identifies it. How can it show JUST absorption, when there is proximate emission too? — how does the spectrum diagram separate the absorption from the concomitant emission?

        The speaker in the video lost my interest, when he treated that spectral gap the same as climate alarmists do. He doesn’t start out by going deep enough into the errors.

        • I’ve never bought into the idea that the gap in the spectrum represents any actual “blocking” or “slowing” or obstruction of radiation of any kind. It represents the nature of CO2 to absorb AND to emit in a particular range

          Quite. But the key point is that emission from the surface occurs at a higher rate than emission from higher in the atmosphere. This can be seen from the Stefan-Boltzmann equation which describes the relationship between Energy and Temperature. Basically, as more CO2 accumulates in the atmosphere the average height at which energy is emitted to space increases which means the rate of emission decreases which creates an imbalance between incoming solar radiation and outgoing LWIR radiation. The result is warming.

          • Less than hand waiving. It confuses energy and heat. Incoming does nit equal outgoing. They are different forms.

          • Nick Schroeder March 14, 2019 at 6:54 pm


            Handwavium nonsense.

            Prove it.

            Prove what? That the upper layers of the atmosphere are colder than the surface? That CO2 absorbs (and emits)? Or something else?

          • Macha March 14, 2019 at 11:07 pm

            Less than hand waiving. It confuses energy and heat. Incoming does nit equal outgoing. They are different forms.

            I haven’t confused anything. Explain what you mean by Incoming not being equal to outgoing? What do you mean by “different forms”? I was referring to energy. The fact that you have failed to elaborate suggests you’re the one who is confused.

          • Nick Schroeder
            March 15, 2019 at 8:11 am

            That CO2 absorbs (and emits)?

            You are kidding right? The IR absorption properties of CO2 have been known about since Tyndall’s experiments in the mid-19th century. I’m sure you must know this so I’m assuming you are angling for something deeper than basic lab experiments.

            Anyway my response to the next question might include material which covers the IR absorption issue. Note that my 2 sources are both noted AGW sceptics. The one you may be less familiar with is Jack Barrett who has written over 70 papers and authored 10 textbooks on various aspects of the chemistry and spectroscopy of small molecules. Jack (a) knows his stuff and (b) is definitely no fan of the IPCC (read his blog). The other is Steve McIntyre.

            and that 0.04% has enough mass to do squat.

            I find it mildly amusing that many of the people who claim that the “tiny” amount of CO2 in the atmosphere can’t affect earth’s temperature are quite happy to accept that this “tiny” amount is essential for plant growth. I’ll quote part of Jack Barrett’s response to this point


            Craig Bohren suggests such people try 380 ppmv of arsenic oxide in their tea! We would encourage a safer experiment. Take a jug containing a litre of water. The water is transparent to visible radiation. But then add a few drops of milk and stir. This is equivalent of diluting the milk by a factor of about 5000, i.e. the milk ‘concentration’ is 500 ppmv. Is there any visible effect?

            The “tiny” concentration of milk blocks the visible part of the spectrum – just as CO2 increases the opacity of the atmosphere.

            Steve McIntyre has a blog post from 2008


            It includes a graph displaying upwelling spectra from the Pacific at 15 km (Top of the Atmosphere).


            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. )

            Neither Jack nor Steve are afraid to get their hands dirty and tackle mainstream climate scientists head on but they both accept that the basic AGW theory is OK – as does Nic Lewis.

          • The large notch or “funnel” in the spectrum is due to “high cold” emissions from tropopause CO2 in the main CO2 band.

            It’s just not that simple! The association of the spectral “funnel” with “high cold” emissions is rendered murky by collisional transfer of CO2-absorbed energy to the “inert” constituents of the bulk of the atmosphere.

          • Quite. But the key point is that emission from the surface occurs at a higher rate than emission from higher in the atmosphere.

            Define “surface”. And then define ‘higher in the atmosphere”. The Earth/atmosphere system emits, and I am not of the understanding that there are any boundary layers that distinctively separate one layer of emission from another layer of emission, the way you describe it.

            In fact, to claim that a distinctive boundary layer, “higher in the atmosphere”, emits more slowly than the “surface” is just another way of saying that this supposedly higher boundary layer BLOCKS the faster rate of surface emission from participating in the whole Earth/atmosphere-system emission to space.

            All I see you doing is cleverly describing the word, “block”, in more words. The slow-emitting boundary layer is “blocking” the rate of the faster-emitting boundary layer.
            That claimed slow-emitting boundary layer is the greenhouse-glass artifact error, legitimized by a fancier description of it.

            This can be seen from the Stefan-Boltzmann equation which describes the relationship between Energy and Temperature. Basically, as more CO2 accumulates in the atmosphere the average height at which energy is emitted to space increases which means the rate of emission decreases which creates an imbalance between incoming solar radiation and outgoing LWIR radiation.

            What can be seen? The Stefan-Boltzman equation certainly does not establish that the claimed boundary layers with different emission rates exist — this claim of two layers has no physical basis for which the SB equation should even be invoked. Invoking SB, before proving the premise of separate emission layers is putting the cart before the horse, as I see it.

            CO2 does NOT somehow accumulate higher up in the atmosphere — it accumulates in the entire volume of the atmosphere, thereby increasing the total volumetric area over which emission occurs, both deep within this volume and higher in this volume. More molecules of CO2 exist within the whole thickness of Earth’s atmosphere and so more emission occurs within Earth’s atmosphere as a whole, as I see it, so the height of emission stays the same, near the center of mass of the whole atmosphere around which mass-center a greater number of CO2 molecules now exists, both above and below the center of mass (all emitting equally now in their larger total volumetric area).

            The result is warming.

            There is no proof of this that follows from the above.

          • I find it mildly amusing that many of the people who claim that the “tiny” amount of CO2 in the atmosphere can’t affect earth’s temperature are quite happy to accept that this “tiny” amount is essential for plant growth. I’ll quote part of Jack Barrett’s response to this point:

            I find it utterly hysterical that many people who claim that CO2 is like arsenic cannot realize the difference between the context of one chemical and its specific chemical constraints (with respect to percentage) and another. I find it sadly tragic that your mild amusement is due to a gross oversight, in this regard.

            Jack Barrett’s response is precisely the sort of chemical-contextual oversimplification that I am talking about. CO2 is NOT like arsenic — it cannot kill humans like arsenic can at its small percentage. All percentages are not created equal, and to equate one small percentage to another small percentage just because of the numerals alone is as intellectually shallow as one can imagine.

            CO2 does not affect the same human chemical pathways as arsenic. To make anywhere near the proper poison comparison in human beings, therefore, you would have to compare 60,000 parts per million CO2 (minimum, I’d say) to 380 parts per million arsenic oxide. Otherwise, you are implying that the human body is exactly like Earth’s atmosphere — clearly a totally absurd, totally false analogy.

            CO2, given its known chemical and physical properties (NOTE the context), cannot do what you and others like you claim. Comparing arsenic’s effect on the human body to CO2’s effect on the Earth, then, is basic false analogy 101.

            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.

            “High cold emissions”, as shown in the large notch, has nothing whatsoever to do with restricting the rate of radiation, as I understand it. Rather, it has to do with the fact that photons emitted AFTER absorption, do not emit in the same line that photons were absorbed, being at about a 45-degree angle (on average) with respect to the directional line at which photons were absorbed, thus creating the signature gap at the respective frequency.

            There is no absorption without concomitant emission. There is no blocking or retaining of the absorption. Rather, after absorption, there is an associated emission at a different angle, creating the signature of the CO2 molecule. I repeat, there is no blocking, or slowing down, or restriction, … just absorbing and re-angling during emission to create a unique signature, … as I am beginning to try to understand it.

            As for “basic AGW theory being OK”, that is your misconstrual, … far from the truth, of course.

    • Seriously, man, even if atmosphere did cool the Earth (the scenario has little to do with our reality) that doesn’t say a thing about what increasing water vapour and CO2 do.

      Your point 2 is a strawman, of course what goes out of Earth is not describeable as a perfect black body or BB from the surface. It’s grade school level to think so, and those who do so can and should be ignored.

      Your point 3 is a misunderstanding, though your convoluted long comments or terse comments like this don’t let the reader to understand and explain them to you.

      Usually I guess a law of thermodynamics is invoked to reject ‘backradiation’. Well the news is GHE does not imply a net energy flow from cooler CO2 to surface. So there is nothing to reject (but maybe amateur explanations of the phenomenon).

      • Unfortunately, “amateur explanations of the phenomenon” are what children are taught and what notable, supposedly respectable organizations put up front to amateur readers.

        No matter how you cut it, the first fundamental misunderstanding of a greenhouse is still an artifact in the most professional descriptions.

        The first step in correcting things is to lose that blasted name. Why keep it, if it clearly was wrong, to begin with, thus requiring mental gymnastics to try redefining it and then still retaining the artifact of this original misunderstanding?

    • Wait a minute, what about all those “Heat Trapping Clouds”. Shouldn’t “Heat Trapping Clouds” cover about a third the earth’s surface at all times? (sarc)

      • I have trouble telling them from “Heat Reflecting Clouds”. You know the ones! When they go over it gets cooler. I guess they’re just less common or something.

    • Nick, Matt, Robert: At 11:30 in this video, Lewis shows the spectrum of thermal infrared observed (black line) AND calculated (red line) leaving our planet. The calculated spectrum is generated using laboratory absorption coefficients and equations that govern the absorption and emission of radiation. See:

      From this, we conclude that – if nothing else changes – increasing amount of GHGs slow down the rate of radiative cooling to space. From conservation of energy, we recognize that this slowdown must result in warming. Warming will stop when outgoing radiation is again in balance with incoming.

    • Since the upper atmosphere is warmer, wouldn’t more “greenhouse” gases cool the lower atmosphere?

      What is the point of being a scientist, if you are too fearful of speaking out against things you know are wrong?

  5. By simply stabilizing emissions, which is a lot easier to do, the decrease in the airborne fraction of emissions will start decreasing atmospheric levels until an equilibrium is reached between Sources + Emissions = Sinks.

    People seem to forget that Nature not only efficiently removes half of what we put in the atmosphere, but it has not only been keeping up with our increase in emissions, but actually taking out a bigger part of them over time. Nature is really hungry for our CO2.

    We just need to sit down and watch, the demographic change in the world is going to decelerate our energy growth as it is already reducing energy per capita in Japan, Finland and Italy, the countries with a bigger old-age dependency ratio. Our emissions are going to stabilize naturally and we can help by being more efficient in our energy use.

      • Yep, and the reason is that nature evolved during much higher concentration then we have now. One of the clearest pieces of evidence that CO2 is not a boogeyman.

    • “we can help by being more efficient in our energy use.”
      Really, Javier??? A Greenie talking point?

      Hey, I got a Great Idea, never been thought of before. Lets’ make things more efficient!
      1) Commercial Aviation: Actually, Boeing Aerospace seems to have that one under control. Every new generation of aircraft is more efficient than the previous. Been this way since forever.
      2) Heavy Transport: Move long haul by rail instead of trucks whenever possible. Already been done.
      3) Make buildings more efficient: In the 1970s, following the “Oil Shocks”, there was a big push to make buildings “more efficient”. All we got for our trouble was “Sick Building Syndrome” (look it up). Turns out, limiting airflow caused moisture buildup and attendant mold and other problems. Lots of buildings became decidedly unhealthy places for some people.
      4) Move oil using pipelines instead of rail. Been thought of. Wait, who is opposed to this efficiency measure? Oh yes, the Greenies.

      Sorry, but these types of pat solutions and throwaway lines just irritate me.

      • You appear to be ignorant of the huge differences in energy use and energy consumption per unit of GDP between countries. It is clear that we can continue improving the energy efficiency of our economies as we have been doing over many decades. I couldn’t care less about your political rants.

        • The point is that humans will always seek to be more efficient. We don’t need any prompting from government or self righteous do-gooders.

          • “The point is that humans will always seek to be more efficient.”
            If by efficient you mean “cheapest”, I probably agree, but that doesn’t alway equate to environmental/sustainable responsibility. Sadly it is often the generation after, who pay for the sins of the generation before.

          • Simon,

            To date, it has been always been the generation(s) after, who reap the significant rewards from the positive developments of the previous generations.

            Simon, are you better off than your great great grandfather(s). Did they die of infection, pneumonia, starvation, rubella, burst appendix, malnutrition, etc? Did they have to put up with painful wisdom teeth? Did 10% of their kids die before their first birthday of ‘unknown’ problems? Did their wives die during childbirth or associated complications?

            Not meaning to imply that your ancestors improved society (and health & well being) but that someones ancestors’ did, and you are the beneficiary /recipient of the outcomes of their greedy ways.

          • DonM
            “Simon, are you better off than your great great grandfather(s). Did they die of infection, pneumonia, starvation, rubella, burst appendix, malnutrition, etc? Did they have to put up with painful wisdom teeth? ”
            We are talking abut different things. You are talking technology and the development of science and health. I have no argument with you on that.

        • Much of this so-called “efficiency gain” was a result of sending massive amounts of manufacturing offshore. It shows up in a horrible balance of trade deficit and subsequent unconscionable national borrowing to stimulate the economy. Borrowed money that flows out to the Chinese. This system will have an unfortunate ending.

          • The loss of importance of the secondary sector towards the increase of the tertiary sector of the economy is a global feature, not specific for the OECD countries.

    • History has show that the more efficient our energy use, the more energy we choose to use.

      • As we were growing in numbers. That will not be the case in the future if current demographic trends are maintained. Unless things change the human population of the planet will reach a maximum within the 21st century and then start decreasing. It will also age considerably, with all the world except Africa having >20% of the population at >60 years old by 2050. Unless this changes energy consumption will follow population trends.

      • Roy,
        I would argue you have the arrow of causality reversed.

        I would argue the more energy we use, the more incentive there is to be efficient.
        This arises from two reasons:
        1) Basic economics of structural supply and structural demand and price of the commodity.
        2) Necessity is the Mother of innovation/invention. IOW, as price increases the drive for innovation and the incentive to do so increases. Thus we get things like better insulation in homes, hybrid- cars (gas+battery to store excess energy, shutdown engine at stop lights etc) with regenerative-braking technology to capture otherwise lost kinetic energy, etc increases. Airlines pushing aircraft makers to better fuel efficient engines and airplanes etc.

        • The arrow goes both ways. It’s a well known phenomena that when gas prices go down, people drive more.

          • I agree the processes are coupled in feedback.

            But to degree demand for fuel is inelastic in economic terms. That means as prices more up there will demands for efficiency gains, more hybrids, developments of new technologies. Those technologies don’t away when prices come down, but people are inclined to forego purchases of more expensive hybrids. More Americans are opting to drive SUV’s everyday for a multitude of reasons, and continued low gas prices helps sustain that market choice. But smaller crossover SUVs are also becoming more popular and simultaneously more fuel efficient.
            That has nothing to do with efficiency directly. Driving a pickup truck more increases the demand for a more fuel efficient Ford F-150 made with aluminum.

      • Intuitively this seems true, but how is energy efficiency measured?

        Regardless of definitions, for all continuing systems, energy flow always is at it’s most efficient level, given all the controlling conditions and the history of the system’s development. When conditions change to impede flow, the system adjusts channels to maximize flow efficiency.

    • The Socialists are way ahead of you on this issue, Javier. They will destroy the economy altogether and we will be following oxen around a field and eating insects if we can find them.

  6. I almost quit after the third graph.

    NL must be blind.

    The 1910 to 1940 warming, prior to our added CO2 of any quantity, is the same as the latest warm burst.

    NL has zero credibility if he says he accepts the 95% likely human caused meme.

    What a disappointment.

    • At 5:25 “The warming is human caused. If you want to get published, you have to go along with that.”
      A moment before, he mentions coming out of the LIA, but it is only lip service.
      1) He accept that all warming from 1880 is human caused, even though it is (or was) agreed that prior to the end of WWII, there was not enough of a human effect to make a difference. (Goal Post moving, anybody?)
      2) He uses HADCRUT and GISS, two utterly hacked data sets. The whole cooling from 1940-1975 has been obliterated from both as shown by archived plot and data sets from the 1970s. The truth is that these records are so badly hacked that you cannot tell what happened for the entire 20th century.

      • Agreed Tony. NL needs to identify all those temperature measuring ships that covered each 40 sq miles of the seven seas each day, from 1850 until our buoy system deployment. As Phil Jones said in his emails: “we just made it up”.

        Now of course, the climateers now use their models to make things up, and of course that causes the past oceans to be cooled(CO2 driven). Pretending natural variation has ceased is a fundamental error!

        I used to respect NL, now? Forget it, he is an amateur. His work would not pass my peer review.

    • Yes when NL accepted the CAGW meme as given I could not be bothered with the rest.

      The fact that at phase change the Plank sensitivity (coefficient) of water is zero means that the purported greenhouse effect is negated. QED.
      Engineers are aware of this when they design their steam engines and that is why these engines are so successful in generating our electricity.

      Hint: Think of the Rankine Cycle.

    • Actually, if you read the Lewis and Curry papers, they say something quite different. NL perhaps did not fully explain it in his talk.
      They accept the IPCC attribution position for he sake of argument and analysis. Nic and Jusoth know full well that the 1920-1945 warming is not attributable to AGW.
      BUT, by assuming it was they accomplish two very useful things:
      1. Washes out the attribution issue from their sensitivity estimates.
      2. Means that their observational energy budget method must be the maximum estimate; the ‘true’ estimate (pdf) MUST be lower.

      When the Maximum possible (a) proves the models wrong and (b) says there is no immediate problem, then I say it is a very usedul simplifying assumption.

      • “They accept the IPCC attribution position for he sake of argument and analysis”

        Fair enough. NL thusly dropped the ball in his video.

      • Except it isn’t the maximum possible. I’ve seen a lot of claims that we would be cooling now if it wasn’t for the CO2. That’s how they get around that problem. The current solar forcing has decreased and volcanoes at the end of the 20th century would have caused cooling. All ocean cycles are considered to have no effect.

        You can’t win by playing their game.

      • If sensitivity is high, then anthroCO2 is combatting an impressive natural cooling, an effort which we can’t sustain.

        However, I’m pretty sure sensitivity is low, perhaps very low. Meanwhile the biome needs all the CO2 it can get, and the whole of society needs the cheapest energy it can get, which now and well into the future is fossil fuels.

        But ‘Atomkraft, ya bitte’ should be in our future. When will the ever learn? When will they ever learn?

  7. Since there are only 4 carbon dioxide molecules per 10,000 of the atmosphere and typically at least 25 times as many water vapour molecules, it’s impossible to see how any atmospheric effect of carbon dioxide from IR absorption and re-emission could not be either zero or so small as to be unquantifiable.

    • In my electrical engineering courses I was taught that when on feedback was less than 1/10 of another feed back that the larger became prominent and controlling. Thus the smaller one could be ignored. Therefore CO2 can be ignored. But wait, …. There is no way to keep water vapor out of the atmosphere thus no way to milk the system,

  8. “There is no point in my view disputing it”. Then well, let me add a view.

    The chart he presents at the 10 to 14 minute mark or so show satelite measured emissions over the sahara desert. Regrettably we are not being told if these are average emissions or if they have been taken during hot day times.

    Anyhow, emissions in the atmospheric window are as high as if the surface had 320K. This is a non sensical statement btw., as emissions not just depend on temperature bust also on specific emissivity. For the sake of argument let us assume that surface emissivity is assumed to be 1, because this fallacy is the one foundation for the whole GHE story.

    320K or 47°C are quite hot, even in the sahara desert. And it is specifically the sahara desert where surface emissivity is very low, less than 0.8(!), as you can see here..

    So even if the desert had 320K and all that radiation was going unhindered through the ATM, far less, only about 80%, should reach the instruments of the satellite. Which brings up the question why we have excess radiation in the ATM (even compared to the MODTRAN Model) and where is it coming from?

    Could it be, that the radiation missing where GHGs are very opaque is still escaping at wavelengths where the atmosphere is transparent? Could it be that Kirchhoff’s law does not fully apply, as pressure and temperature change through the atmosphere and thus modulate the radiative properties of assumed GHGs? Just an idea, but anyone looking at this chart should try to answer why we have excess radiation in the ATM.

    • I am equally puzzled about those numbers.

      I have never been to the Sahara, but I’ve spent time in the Kalahari, Namib and Nevada deserts and they all have these features in common: (1) the air is very dry, and (2) even when it’s very hot in the daytime, it gets very cold, very quickly after the sun goes down (exactly as epitomized by the old saying that “more people freeze to death in the desert than die of heat stroke”).

      My simplistic (or is it?) conclusion from these two observations is that there isn’t a whole lot of greenhouse effect in desert areas, because there’s so little water vapour in the air.

      So why is Nic showing radiative heat flux over the Sahara? Why not over an ocean? or a tropical rain forest? or a temperate forest? or a boreal forest? or mixed use farming country? Is it because absorption of OLR is dominated by water vapour in those areas? Wouldn’t be so dramatic, perhaps?

      Nic Lewis is a lukewarmer, and it hurts to see someone so obviously bright, accept, without question, HADCRUT historical temperatures that have been adjusted and re-adjusted so that the 1945-1975 cooling has almost disappeared. He also shows no curiosity about the palaeo-temperature records. But, that said, he uses mainstream climate data and mainstream climate assumptions (“it’s all down to CO2”) to show that alarmist projections are wrong. So good for him.

      • It gets far more complicated if you add another perspective. That graph is including the effect of clouds..

        Note that those moist areas at the equator are emitting over 100W/m2 (~200W/m2 vs. ~300W/m2) less than the dry areas north and south of it.

        One could argue this was due to the relative abundance of vapor. However the desert air is not that dry in absolute terms, with a relative humidity of about 30%, while those moist areas show like 60-70% relative humidity, both at similar average temperatures. The point is, that doubling vapor can not drop emissions by a 100W/m2, not even close to anything in this magnitude.

        Obviously clouds are almost entirely responsible for this drop in emissions. But even the desert does not have a 0% cloud cover, and the moist areas by far do not have a 100% cloud cover. Realistically we could assume a 10% cloud cover over the desert, and 60% over moist areas for instance. Then a delta of 50% in cloud cover would mean a 100W/m2 in more or less emissions, or by about a third. And based on the assumption of 50% delta (60%-10%), any cloud cover would drop emissions by even 2/3s.

        Now this is very simplified and just meant to show the basic idea. If one takes a much closer look at weather data, this is not just confirmed but enhanced. An opaque cloud cover will effectively drop emissions by about 85%. Average global cloud cover will thus have a positive forcing of about 80-100W/m2, which is more than the albedo effect of clouds.

        So eventually, the “GHE”, if we still want to call it that way, is not caused by GHGs, but by clouds.

      • Desert temperature fluctuations from day to night have nothing to do with greenhouse effect from humidity or lack thereof. Moist air has greater enthalpy which keeps temperatures higher after sundown. Drier air does not have that enthalpy so it cools faster. Additionally, clouds reflect sunlight from above to keep temperatures lower during the day.
        Greenhouse effect is another matter altogether.

  9. As Nic Lewis accepts the temperature record from HADCRUT, I tend to regard his findings of TCS as a maximum. The “records” in HADCRUT and GISS are fairly well known to run warm, so the TCS derived from them is exaggerated.

  10. Somebody, please, tell Nic Lewis to take elocution lessons! I’d love to hear this lecture, but I can’t understand him. To be sure, I’m hard of hearing, but I can understand most speakers by using headphones and/or hearing aids. With Lewis, I fail almost completely. The way he speaks is amazing. I don’t think I’ve ever heard anything like it.

    • Frog
      His English accent doesn’t help, especially for those of us attuned to an American-English accent. It is the old joke about two peoples being separated by a common language.

      • Clyde
        Maybe the English accent doesn’t help, but if so, this would be very minor. I’ve had trouble with lower-class English accents, but I’m not sure I’ve ever had trouble with others.

  11. NL is instructing us on CO2 molecule physics? Move over Dr.Happer?

    NL says the models calculate the OLR curve quite accurately. I looked at his slide and saw a major discrepancy. I see that water vapor is getting thermalized by the activated CO2 molecules, and they are dissipating more heat than is predicted by the calculated curve.

    • NL describes the “trough” in the absorption band at 15 um at 12:34 into his lecture. He states that this is a broad band and it will get wider as CO2 increases. It is my understanding that CO2 per se absorbs at very specific and relatively narrow bands. And I don’t understand why those bands would widen with a bit more CO2, nor do I think his attribution of all the absorption in this region to CO2 is correct. Is this what you mean by thermalized?

      • Thermalization is the fact that an IR excited CO2 molecule virtually never gets to radiate that energy, as before it can it loses its energy to thousands of collisions with other atmosphere molecules.

        In return, a CO2 molecule can gain energy from collisions, and radiate that energy through an IR photon.

        Look for Dr Happer’s lectures, he says” He says “the inadequacies of the Voigt profile for far-wings of the CO2 band have already been demonstrated experimentally many times”

        Dr Spencer also has a nice write up:

        • “Far-wings” and “shoulders,” as well as “pressure broadening,” these are the buzz-words they use to imply that more CO2 gives more heating of the atmosphere.

          The truth of the matter is, CO2 is already opaque to surface OLR at an altitude less than 10 meters, essentially all 15-micron radiation is already absorbed and thermalized. More CO2 just lowers this altitude by a millimeter or two.

          At the TOA more CO2 increases the altitude at which the atmosphere freely radiates to space, thus lowering the temperature at which the atmosphere radiates to space, thus retaining some additional heat in the atmosphere. NO ONE has calculated the magnitude of this effect, and maybe no one can.

          • AC Osborn,

            The atmospheric temperature at the TOA are close to the temperature correlating to the 15 micron absorption spectra of CO2. Thus, higher CO2 concentration raises the altitude at which CO2 is OPAQUE to those Outgoing Long Wave Infrared rays.

            Does that clear it up for you?

        • Not buzz-words. They are real phenomena, though rather weak, which is why more CO2 has very little effect on temperature. There is also doppler broadening, also quite weak.

          And there is another phenomenon almost never mentioned. In the middle of the CO2 band emission takes place above the tropopause where temperature rises with altitude, so there more CO2 actually has a net cooling effect.

          • I have pointed many times to the presentation in the 2013 AGU meeting by NASA that clearly demonstrates more CO2 more & faster cooling at the TOA.
            I really do not understand this “At the TOA more CO2 increases the altitude at which the atmosphere freely radiates to space, thus lowering the temperature at which the atmosphere radiates to space, thus retaining some additional heat in the atmosphere.”
            based on the satellite results from that presentation.
            So the latest Satellite data says that the Atmosphere has shrunk quite a lot due to the quiet Sun, do those same people think that due to the lowering of the radiating level it will now be cooler?

    • Nic Lewis quite clearly indicates this is the “Sahara Desert” atmosphere of extremely low H2O vapor.

      That said in his defense on this particular slide, it is the atmosphere above the oceans and in the moist tropics, with their much higher levels of TPW, that drives our climate. So water vapor is the dominant GHG.

      • That is true but was not NL’s point. His point was that the Modtran radiative transfer model nicely matches what TOA observes. Proving that CO2 is a geenhouse gas (ghg) and that the water vapor feedback (even over the Sahara desert) is positive.
        Your separate point that Water vapor is the most important ghg is true, but not the point he was making.

        • ” Proving that CO2 is a geenhouse gas (ghg) and that the water vapor feedback (even over the Sahara desert) is positive”

          ?? how?

          The graph I saw was not nicely matched everywhere.

        • Water vapour is a +ve feedback for sure, but is water in all its phases a net +ve feedback?

  12. Can someone PLEASE explain to me WHY as I look at charts of the Global Temperature and Atmospheric CO2 over Geologic Time for the last 500 – 600 Million years that presently the Global Temperature is at a minimum and very close to the lowest temperature over those 600 Million years? Further the periods of the Global temperature being at or close to 10 – 12 degrees C over those 600 million years is LESS than 80 Million years. The remainder of the time the Global Temperature was close to 25 Degrees C and shows NO, NONE, Zero correlation to CO2 Levels. Thes convinces me that the NORMAL Global temperature is closer to 25 degrees C and NOT 12 Degrees C. This shows me that Global temperature is closely related to CO2 if at all. And probably not at all.
    Nearly a Billion years of 25 degrees C and Nearly 90% of that time at that 25 degrees C. Yet, here we are, leaving an ice age and it is only logical to assume that after a Ice Age ends the Globe will warm up, and will not warm up instantly. However the Enviro Whackos Illogically blame this Natural warming on CO2.

    • Because the global temperature 600 million years ago has zero impact on humans. The current climate is what we are used to and it doesn’t matter of the Earth was sizzling hot long ago, or freezing cold. It’s not relevant to today. If you tell me, “But it shows how variable the climate system is naturally”, well, humans don’t care about temperature changes on the time scale of millions of years. They care about a few years, decades, or maybe a couple hundred years into the future.

      • Roy Spencer, the significance of the temperatures and CO2 levels 500 million years ago is that the “sensitivity” coefficient must have been similar since the radiative mechanism is unchanged. If the changes in the distribution of land and ocean can significantly effect this magical coefficient then we have much bigger problems than Al Gore’s fleet of SUVs and corporate jets.

        • Robert – the problem is that 500 million years ago, we were in the Cambrian period. The atmospheric composition was very different than it is now. In particular, there was very little oxygen. Also, the continents as we know them today had not formed. The Earth revolved more quickly.

          • The continents existed, but were somewhat smaller and very differently configured. And there was certainly a fair amount of oxygen in the atmosphere, since largish active animals existed. Earth rotated faster, yes, but not dramatically faster.

            And the sun was significantly weaker.

        • The significance of the temperatures and CO2 levels 500 million years ago is that our ancestors, of whatever form they had, survived those times and propagated, becoming a part of a continuous sequence of living things that continues uninterrupted even today.

      • Hmm.. Roy, you ignored his question.

        “Can someone PLEASE explain to me WHY as I look at charts of the Global Temperature and Atmospheric CO2 over Geologic Time for the last 500 – 600 Million years that presently the Global Temperature is at a minimum and very close to the lowest temperature over those 600 Million years?”

        • I do not have it exact, but here is a general scheme. You can look it up for better detail.
          Obviously, the placement of the continents has a huge effect on ocean currents. Specifically, heat transport from the tropics to the poles. Central America had not yet formed, and Africa was well clear of Europe. So there was a clear path in equatorial regions all around the planet. Antarctica was in the southern temperate zone, so no ice cap. This would have had a profound effect on heat flow and planetary climate in general. Remember 600 million years is a long time even for continental drift, so you are looking at huge changes in the planet. The current ice age started 2-3 million years ago with the closing of the pathway between the Pacific and Atlantic oceans by Central America. Compared to your 600 million years ago, that is just 0.5% of the time. Nonetheless, in a glaciation 80-90% of the time, and things cool off.

          • Actually the current glacial epoch started 35 million years ago with the Oi-1 glaciation in Antarctica once the circumpolar southern ocean isolated Antarctica. Antarctica has never been ice-free since then, except locally along the coast.

            And about the same time the first major mountain glaciers grew in the Arctic, though major lowland glaciation only started in the Pliocene.

        • Because we know what caused temperature changes millenia ago and that is not the case now.
          To whit, an orbital cycle conducive with greater absorbed solar SW over higher northern landmasses, with CO2 levels following rising SSTs as +ve feedback.
          CO2 is a GHG, and therefore will attenuate the Earth’s ability to cool as a driver when added to the atmosphere without the milankovitch forcing.
          And it’s “very close to the lowest temperature” because said orbital cycle was in cooling phase at the onset of the industrial revolution.
          It is also the case that atmospheric CO2 levels are at their highest in 15-20 million years ….

      • Roy Spencer
        “humans don’t care about temperature changes on the time scale of millions of years. They care about a few years, decades, or maybe a couple hundred years into the future.”

        Bingo! The planet has been warmer and cooler than today. So what? It’s what happens while “we” are here that matters.

        • Well, we survived the glaciation. We’ll survive easily with +2C or +3C, if it comes to it. It appears as if +1C has had almost no negative impact based on how climates of 1750 can’t be regarded as perfectly warm.

          My own trust in activist scientists has melted as there has not really been so much warming during the past 2 decades. What has more happened is that the past has been estimated colder and colder, all the time. So that is supposed to make current climate worse?

        • Classic, history started in 1970 type answer, what humans care about is NOT SCIENCE!
          It is FEAR MONGERING.

    • Can someone PLEASE explain to me WHY as I look at charts of the Global Temperature and Atmospheric CO2 over Geologic Time for the last 500 – 600 Million years that presently the Global Temperature is at a minimum and very close to the lowest temperature over those 600 Million years?

      Nobody knows. Several hypotheses about why Ice Ages take place. The present one (Late Cenozoic Ice Age) has been made cooler by the position of Antarctica over one of the poles, by the closure of the Panamanian gateway, and by the rise of the Himalaya.

    • PART of the difference could be different geology- a larger portion of continents were covered by inland seas, moderating climates. In addition , I suspect periods of mountain building would tend to make the world cooler. Having given all those caveats, I went to The April 25, 2009 “Reference Frame”,

      Lubos Motl didn’t allow for a fainter Sun in the past. See equation 1 here:

      ppm <-c (4500, 4200, 4500, 2200, 800, 900, 1750, 1950, 1700, 500, 280,400)
      temp <-c(21, 16, 17, 20, 14, 16, 17, 16.5, 18, 18, 14, 14.5)

      Adjust for faint sun Gough formula L= 1/(1-0.4( 1 – t/t0) where t0 is 4.57 billion years. With current temp about 14.5 C
      temp adj factor
      adj<-c( 1.0498,1.0446,1.04043,1.03779,1.03244,1.02687,1.0225,1.01773,1.012855,1.005722,1.00202,1)

      I set temp= temp/adj to get revised temperatures with sun cancelled out.

      After adjusting for the faint young Sun, the Earth is STILL cooler than the average for past periods, and a doubling of CO2 would STILL result in a warming of only 0.772 degrees.

      Of course, the calculations don't take into consideration the fact that CURRENTLY the Earth is in an ice age, and SHOULD be colder than average for reasons OTHER than background CO2. ALSO, the calculations ASSUME CO2 is the controlling factor. In fact, there were definitely OTHER factors affecting BOTH climate and CO2 in past periods.

      By the way, the p value I got was 0.078, not statistically significant.

      • After giving it some thought, I realized I needed a few corrections.

        ppm <-c (4500, 4200, 4500, 2200, 800, 900, 1750, 1950, 1700, 500, 280,400)
        temp <-c(21, 16, 17, 20, 14, 16, 17, 16.5, 18, 18, 14, 14.5)
        temp=temp + 273 #adjust for absdolute temp
        #Adjust for faint sun Gough formula L= 1/(1-0.4( 1 – t/t0) where t0 is 4.57 billion years. With current temp about 14.5 C

        adj<-c( 1.012314,1.010788,1.009982,1.009316,1.008014,1.006652,1.005569,1.004403,1.003198,1.001427,1.000050,1) #adjustment factor for faint young sun
        #Now, calculate the base-two logarithms of the CO2 concentrations:

        log2ppm<-c(4.0064263, 3.9068906, 4.0064263, 2.9740048, 1.5145732, 1.6844982, 2.6438562, 2.7999754, 2.602036, 0.83650127, 0.0,0.51457)


        After rerunning the program, I get a 1.7268 degree warming for each doubling of CO2.
        Wee p value of 0.00216, but but with summed series, , bogus p values are common. As before, the correlation ASSUMES CO2 controls temperature, when in reality the CO2 was a feedback factor.
        fitted(m) shows the Earth should now be at 15.5 C, so it's cooler than predicted. Possibly because of the fact we're in an ice age- possibly controlled by ocean circulation- North and South America were joined about the time the ice age fluctuations started.

  13. Moderator : feel free to suppress this comment, or better, the one I posted in the comments section of “Emails reveal how children become pawns of climate alarmism” since they share the same arguments.

    1) “greenhouse” gases are the only way for the atmosphere to lose heat into space :
    – by definition, in the atmosphere only “greenhouse” gases absorb (and hence emit) in the infrared region,
    – the atmosphere can lose thermal heat into space only by thermal radiation (neither conduction nor convection exists in the vacuum) and according to atmospheric temperatures, this thermal radiation takes place in the infrared region,

    Hence, “greenhouse” gases infrared emission is the only way for the atmosphere to lose heat into space,

    2) Heat balance of “greenhouse” gases (Data are from [Kiehl and Trenberth 1997]) :
    – on the one hand, thanks to “greenhouse” gases infrared emission (see 1)), the atmosphere radiates 165 W/m² into space,
    – on the other hand, “greenhouse” gases absorbs 26 W/m² from the Earth’surface thermal radiation.

    Hence, the net radiative balance of “greenhouse” gases is to cool the atmosphere, even if in this process, they absorb (and emit backward) some of the Earth’s surface thermal radiation.

    [Kiehl and Trenberth 1997] :

    • This is like saying the walls, windows, and doors of your house are the only ways for your house to lose heat in the winter. It’s true, yet those surfaces are what help the inside of your house stay warm.

      • Roy,

        Q = U A dT, the insulated envelope, is what makes the inside warmer than the outside as well as cooler inside than out. The atmosphere is a second year HVAC problem.

        Heat leaves the surface by several transfer methods: conduction, convection, advection (motion), latent and radiation. The non-radiative participants mean the surface cannot radiate as a BB.

        I demonstrated this quite clearly with two classical experiments. For a surface to radiate BB requires a vacuum, i.e. a non-participating contiguous media.

        Surface Emissivity = radiation / (cond + conv + advec + latent + rad) In the case of a K-T diagram: emissivity = 63 /(17 + 80 + 63) = 0.16

        U is a combination of all of the heat transfer processes.

        At 0.04% of the mass the thermal conductivity, U, contribution of GHGs is negligible.

        • “Heat leaves the surface by several transfer methods: conduction, convection, advection (motion), latent and radiation. The non-radiative participants mean the surface cannot radiate as a BB.

          This needs to be said over and over.

        • Better put those experiments on YuTube, Nick. Sounds like it should be right up there with Bill Nye stuff. Really U A dt? A forced convection approximation applied to radiative heat transfer that is proportional to T^4. Just not gonna be demonstrable.

      • Dr Roy Spencer,

        as I understand it, your point seems to be that the atmosphere (like the walls, doors and windows of my house) helps Earth’s surface stay warm.

        This is not what I’m trying to contradict. The fact that the atmosphere helps the surface stay warm or not is not my point.

        Furthermore, the “Surface, atmosphere, vacuum inside, walls, winter” analogy do not stand since :
        – walls lose heat by conduction, convection, radiation, while atmosphere lose heat into space only by radiation,
        – walls help inside stay warm because they stop heat transfer by convection while atmosphere contribute to heat transfer by convection.

        The best analogy would be “Surface, atmosphere, vacuum inside, spacelab walls, vacuum” :
        – but can we say that the spacelab walls help the inside stay warm ? Not really … especially when the Sun shine. The fact is that the main issue with space lab is to cool it down not to warm it :

        Back to my goal.

        My goal is to answer the question :
        – do greenhouse gases warm the atmosphere or do they cool it ?

        The short answer :
        – Kiehl and Trenberth’s diagram shows that greenhouse gases cool the atmosphere more than they warm it since greenhouse gases emit more into space (165 W/m²) than they absorb from the Earth’s surface (26 W/m²).

        The long answer using a reductio ad absurdum argument :
        Suppose that greenhouse gases suddenly lost their ability to absorb / emit in the infrared spectrum :
        – 26 W/m² would be directly lost into space by the Earth’s surface,
        – but the atmosphere would not be able to lose 165 W/m² into space (neither convection nor conduction in the vacuum, hence no way to lose heat into space without radiative heat transfer),
        – in these conditions, the only way for the atmosphere to lose heat would be to transfer it to the Earth’s surface losing it by conduction and convection. To do this, it would have to be warmer than the surface (second law of Thermodynamics) and hence, to increase its mean temperature.
        – this heat transfer would take place (and hence the atmosphere temperature would have to increase), because if not, Earth+Atmosphere system would never reach radiative equilibrium with incoming sun radiant emittance.
        – The Earth’s surface temperature would then increase and hence would emit more radiative heat.
        – Another way to contribute to radiative equilibrium would be to induce more evaporation, convection and clouds formation in order to increase atmospheric albedo. But even is this case, Earth’s surface would have to increase its temperature (and as seen above, this would be possible only with a warmer atmosphere).
        – In summary : if greenhouse gases lost their ability to absorb / emit, the atmosphere AND the Earth’s surface temperatures would increase.

        Conclusion :
        – Greenhouse gases radiative effect is to cool the atmosphere and the Earth’s surface.

        Best regards,
        Marc Bardinet

        • Petit,
          Greenhouse gas theory says the atmosphere warms the earth.
          That is demonstrably false.
          Space is hot not cold, i.e. 394 K, 121 C, 250 F.
          Without an atmosphere/0.3 albedo earth would be much like the moon, 0.12 albedo, blazing hot on the lit side, bitter cold on the dark. See Nikolov & Kramm.
          GHG LWIR does nothing!!!
          The earth surface is warmer than ToA because of Q = U A dT.

          • Nick,

            thank you for your complementary information.

            To clarify my point :

            My aim is to disprove the greenhouse gases theory using data, observations and basic physics that alarmists agree with.

            My aim is also to construct an argumentation that can be understood by the layman.

            This is why, for instance :
            – I mostly use Kiehl and Trenberth’s diagram,
            – I do not counter (perhaps should I) the (wrong) assumption that Earth’s surface radiates like a black body (indeed : why surface would have to radiate if evaporation, conduction, convection are already doing a significant part of the cooling ?),
            – I do not expose the fact that radiative fluxes ARE NOT radiative heat transfer (I just take the net balance of surface upward minus atmospheric+clouds backward radiative fluxes).

            Hope this helps clarifying my point !

    • “Hence, “greenhouse” gases infrared emission is the only way for the atmosphere to lose heat into space”

      Not true.

      On a clear day, the earths surface radiates directly to space, short wave reflection and LWIR.

      “Hence, the net radiative balance of “greenhouse” gases is to cool the atmosphere”

      There can be a changed temperature profile in the Stratosphere. Not so much in the Troposphere. The first 10 meters on a quiet day might be warmer, but that disappears with any wind mixing. A changed Stratosphere (cooler) might cause less circumpolar winds. The temperature effects of CO2 might be so small as to never be measurable beyond natural variation.

      • “On a clear day, the earths surface radiates directly to space, short wave reflection and LWIR.”
        Shown by the simple observation that it gets much cooler on CLEAR nights than on cloudy nights. Have seen heavy frost on the grass with an accurate thermometer showing 34 – 37 degrees F – before sunrise while walking dog.

        • Q = U A dT

          dT gets smaller and the surface cooler because ISR, Q, decreases. U is higher because there are no cloudy curtains.

          Frost happens from evaporative cooling when the wet bulb/dew point drop below 32 F.

    • Petit,

      The following is a real “snip” magnet. Tell me how I’m wrong. No whining about how I don’t listen. Bring science.

      By reflecting away 30% of the incoming solar energy the atmosphere/albedo make the earth cooler than it would be without the atmosphere.

      Greenhouse theory has it wrong.

      The non-radiative processes of a contiguous participating media, i.e. atmospheric molecules, render ideal black body LWIR from the surface impossible. The 396 W/m^2 upwelling from the surface is a “what if” calculation without physical reality. (TFK_bams09)

      Greenhouse theory has it wrong.

      Without the 396 W/m^2 upwelling there is no 333 W/m^2 GHG energy loop to “warm” the earth.

      Greenhouse theory has it wrong.

      These three points are what matter, all the rest is irrelevant noise.

      • Nick, your numbers are from a trenberth type chart. 396 is the energy in the IR photons from ground upward to sky. 333 is the energy in the IR photons from sky downward. To simplify as much as possible, the SB equation is
        q= factor x (Thot^4 – Tcold^4)…..
        396 = factor x Thot^4.
        And 333 = factor x Tcold^4, the second “cold” half of the SB equation
        Just basic radiative heat transfer. The 333 is not a “loop”.

        • And I should add, the net heat from ground to cooler sky is thus 63 W/sqM, which is about 1/3 of sunlight absorbed by the ground, Compared to evaporation of 78 and convection of about 22, depending on which Trenberth’s version you use. Net IR, evaporation and convection from the ground add up to the 168 or so absorbed by the ground. Trenberth’s are daily/annual averages. Sunny midday, and cloudless midnight are hugely different.

          • I forgot my basic point. Which is:
            “Nick has it wrong, Greenhouse theory has it right!!!”

        • This simplified net S-B radiation is handwavium nonsense.

          Instead of cherry picking S-B terms use the entire equation including both areas and emissivity.

          1) atmosphere cools the earth.
          2) 396 W/m^2 is a calculation, i.e. not real & no it isn’t measured.
          3) No 2) means no 3)

          The Instruments & Measurements

          But wait, you say, upwelling LWIR power flux is actually measured.

          Well, no it’s not.

          IR instruments, e.g. pyrheliometers, radiometers, etc. don’t directly measure power flux. They measure a relative temperature compared to heated/chilled/calibration/reference thermistors or thermopiles and INFER a power flux using that comparative temperature and ASSUMING an emissivity of 1.0. The Apogee instrument instruction book actually warns the owner/operator about this potential error noting that ground/surface emissivity can be less than 1.0.

          That this warning went unheeded explains why SURFRAD upwelling LWIR with an assumed and uncorrected emissivity of 1.0 measures TWICE as much upwelling LWIR as incoming ISR, a rather egregious breach of energy conservation.

          This also explains why USCRN data shows that the IR (SUR_TEMP) parallels the 1.5 m air temperature, (T_HR_AVG) and not the actual ground (SOIL_TEMP_5). The actual ground is warmer than the air temperature with few exceptions, contradicting the RGHE notion that the air warms the ground.

          • You are denying thousands of experimentally confirmed results as “handwavium”. Yes the 396 is calculated from another parameter, just like ordinary thermometers measure the liquid level in a tube, and the temperature is inferred by volume calculations. Your Gish gallop of irrelevant information does not change the fact that “Nick has it wrong, GHG theory is correct”

        • This is the complete S-B radiation energy equation in kJ/h for hot system/surface 1:
          S-B σ = 5.67E-8 W/m^2-K^4 & W=3.6 kJ/h
          Q1, kJ/h = (σ * ε1 * A1 + T1^4) * 3.6 kJ/Wh
          This is the complete S-B radiation energy equation in kJ/h for cold system/surface 2:
          Q2, kJ/h = (σ * ε2 * A2 + T2^4) * 3.6 kJ/Wh
          This is the difference between the two:
          (Q1 – Q2), kJ/h = (σ * ε1 * A1 + T1^4) * 3.6 kJ/h – (σ * ε2 * A2 + T2^4) * 3.6 kJ/Wh

          The difference is not some kind of “net,” but the work required to create and maintain this energy imbalance between these two system/surfaces, i.e. a refrigerator.

          System 1 = work + system 2
          (σ * ε1 * A1 + T1^4) * 3.6 kJ/Wh = Work, kJ/h + (σ * ε2 * A2 + T2^4) * 3.6 kJ/Wh

          The 396 W/m^2 upwelling is a theoretical calculated S-B power flux for any surface at 289 K, 16 C. It’s not real.
          The 333 W/m^2 net downwelling from the troposphere would have a S-B temperature of 276.8 K or 3.8 C.
          Actual measured tropospheric temperature at 11 km is -60 C, 213 K, 117 W/m^2.
          333 W/m^2 is obviously bogus:
          1) it’s based on that 289 K theoretical calculation and is likewise not real
          2) radiation requires a defined surface and the 333 does not have one,
          3) it’s wrong.

          • “Work”….wow….now you are incredibly wrong assuming you are talking about work in the thermodynamic sense. Glad to see you got into reading the SB equation and got a bit of a handle on emissivity. Ground about .95. For atmospheric emissivity see my note to Michael Moon a couple of comments below. Now just admit there will be less Q to outer space if the sky has a temperature, and you will discover the GHE!!

    • “1) “greenhouse” gases are the only way for the atmosphere to lose heat into space :”

      Not so. 99% of atmospheric gases (nitrogen, oxygen) radiate IR. I know some people will tell me that it’s not much, but when I ask what are the IR fluxes of nitrogen, oxygen and CO2 (pure gases), no one can say. The values I have are 0.001, 0.018 and 0.134, respectively, but I’m not certain.

        • This is correct. All matter above Absolute Zero radiates all the time in all directions. The entire Atmosphere radiates to space, except those very few molecules at the edge of the atmosphere hundreds of kilometers up which are no warmer than the Cosmic Microwave Background at 2.7 K, which is degrees Kelvin if someone does not know that.

          • The emissivity of N2 and O2 are so low that they essentially radiate nothing. They are however, transparent to IR. Which is different than “radiating”. N2 and CO2 in the atmosphere radiate nothing. Instead let all IR pass through transparently for a few meters until the photon hits one of the 4 in 10,000 molecules that are CO2, or at low altitudes, the photons hit mostly water vapour. Those greenhouse gas molecules absorb the IR photon, and then spit it out again….
            From outer space, if you had an infrared thermometer pointed down, and no H2O or CO2 in the atmosphere, your thermometer would read the ground temperature. But in reality, there is water vapour, CO2, and clouds in the way, so your downward pointed satellite mounted IR thermometer reads the temperature of clouds tops, upper troposphere, etc, colder than the ground, a lot warmer than outer space. Play with Stefan Boltzmann equation from there to help understand the “greenhouse effect”.
            If you get that far, effective sky emissivity from

          • This is not true for gases at atmospheric temperatures :
            – they can’t, even approximately, be considered as black or grey bodies since their radiative properties vary too strongly and rapidly across the spectrum.

            I also did this wrong assumption myself, applying the BB model I was taught to about everything without taking account of the application domain.

            The cinetic energy involved in collisions at atmospheric temperatures is too weak to allow any radiation from N2 (which radiates wavelengths < 1,5µm) and O2. At these temperatures, only CO2, H2O and O3 are to be taken account of in thermal radiation.

            See for instance Modest 2003, Radiative heat transfer – Chapter : Radiative properties of molecular gases.

          • “From outer space, if you had an infrared thermometer pointed down, and no H2O or CO2 in the atmosphere, your thermometer would read the ground temperature”

            That is a limitation of the technology. Thermoelectric transducers cannot measure IR from non-dipole gases. Raman spectroscopy is required, and it can and does pick up IR from O2 and N2.

          • Dmackenzie

            “The emissivity of N2 and O2 are so low that they essentially radiate nothing.”

            So if I remove the CO2 and turn off the sun the atmosphere won’t cool except through convection to the surface and radiation from there?

            If that’s the case then CO2 is a tremendous radiator because the atmosphere cools pretty damn fast at night.

          • Bob Boder, if you remove the greenhouse gases and turn off the Sun, the Earth would cool off pretty fast because its heat would radiate to outer space through the transparent O2 and N2 atmosphere. Then the atmosphere would cool down by contact with the cold ground. If you somehow made the surface of the Earth comletely reflective, it would take a long time for the N2 and O2 no GHG atmosphere to cool down because the emissivity of N2 and CO2 is essentially zero.

      • Yes, N2 have indeed multiple absorption lines in the near infrared (just above 1 µm), but when I compute (with the relative band radiance from 0 to 1,5 µm for a black body at 289 K (the Earth’s surface) with respect to its total radiance, the result is 3e-9/125.9 = 2,4e-11.

        That’s why I neglect O2 and N2 and Argon (which has also line bans between 1 and 1,4 µm).

        • I’m not interested in what oxygen and nitrogen absorb from the earth (if that’s what you mean), but what they radiate according to their temperature. Perhaps I don’t clearly understand what you mean…

          • Their temperature (hence their mean cinetic energy = (3/2) k T) is to low for them to radiate in the atmosphere.

            If I’m not wrong, for N2 to radiate a photon with wavelenght l = 1.4µm in a collision, the temperature has to verify :

            hc/l = hc/3kl >= 3000K.

            O2, N2, Argon can then be neglected as “greenhouse” gases in the atmosphere, which temperatures are far lower than 3000K in the first 100km.

            Nevertheless, should we have to take account of them, by definition, they would integrate the “greenhouse” gases class. This is why I did not mention which gases are greenhouse gases but rather gave their definition.

          • Something went wrong with the formula.

            I meant :

            hc/l = 2*(3/2) k Tmin

            hence :

            T >= hc/3kl

            hence :

            T >= 3000K

      • Icisil,
        To correct a misinterpretation, N2 and O2 are TRANSPARENT to IR. This is different. If Earth’s atmosphere was only N2 and O2, your upward pointed IR thermometer would read -270 C, the temperature of outer space. Because the atmosphere has greenhouse gases in it that are the same temperature as the O2 and N2, those greenhouse gases radiate at the temperature of the atmosphere. Therefore the “sky” is a lot warmer than outer space, and clouds are even warmer yet at around 0 C at temperate latitudes, again as read on your upward pointing IR thermometer. Buy a cheap one, try it out on cloudy days, daytime sky, nighttime sky.

        • Thermoelectric transducers cannot measure O2 and N2 IR, but raman spectroscopy can, at the emission spectra of 2338 cm-1 and 1556 cm-1 (respectively) that are predicted by quantum mechanics.

          • Icisil,
            Uh huh, because there is so little emission, the bands being so few and narrow you can’t really say there is an effective emissivity. Emissivity being meant to be a multiplier times the continuous black body curve to do “gray body” calculations, and not really for calculation of emission in “bands”.

        • DMacKenzie

          Your statement proves that CO2 cools the atmosphere is doesn’t warm it. And I don’t even know if that’s true or not but your argument clearly contradicts the point you are trying to make, I would suggest going back to the drawing board or just stop posting.

          • Wow, you got THAT from my comments? Let me clarify, CO2 and H2O in the atmosphere causes the ground to be warmer than would an atmosphere without any CO2 and H2O. Simply because they introduce a layer with a radiating temperature that is intermediate between the ground and outer space.
            CO2 and H2O absorb and re-radiate IR. You might want to have the picture in mind that they radiate at the temperature of the N2 and O2 that they are mixed with. But gases radiate a quite fixed wavelengths, unlike the continuous curves of a black body or gray body. N2 and O2 themselves radiate so little that you can assume it is zero. But they are transparent and let IR pass from ground to outer space unhindered. It’s not that difficult.

          • @DMacKenzie

            But gases radiate at quite fixed wavelengths, unlike the continuous curves of a black body or gray body.

            I have never understood that statement in the context of the Earth’s disputed Energy Balance. If the Sun is a great big ball of gas (mostly hydrogen), and “gasses radiate at quite fixed wavelengths”, then why do Climate Scientists start their calculations evoking Stefan–Boltzmann with “Backbody Radiation” coming from the Sun?

    • ” Petit_Barde March 14, 2019 at 10:35 am “.
      The actual “Green House” Gases are Nitrogen & Oxygen.
      Because they get just as hot as the CO2, but cannot radiate the heat to space, CO2 cools the atmosphere and thus the surface.

      • AC, your interpretation is interestingly “not even wrong”, read my foregoing comments to Icisil, Bob Boder, Michael Moon, and Nick Schroeder who are confused on differing points regarding radiative heat transfer.
        Sort of yes, CO2 cools the atmosphere by radiating heat to outer space, but at the same time it radiates back to the ground. And it follows the equation
        q= factor x (Thot^4 – Tcold^4). Whether Thot is the ground and Tcold is the sky, or Thot is the sky and Tcold is outer space.

        • Kenzie Kenji,

          I am not confused. Professor Wang was not confused. All Matter Above Absolute Zero Radiates, at a frequency determined by its temperature. It is because of charged particles bouncing off each other and vibrating.

          Back to school for you…

          • Michael Moon,
            …so little emission that it is essentially zero…. is what I said. Professor Wang probably didn’t get around to gas radiative IR emission. Go ahead, search the internet for the emissivity of N2 and O2. Let me know what you find for them and CO2 as well. Compare some radiant heat calcs with those emissivities…

    • “[G]reenhouse” gases are the only way for the atmosphere to lose heat into space

      One of many shibboleths that undergird “climate science” is the notion that only LWIR from GHGs is important. In fact, ALL matter above zero Kelvin radiates energy somewhere in the EM spectrum. The “inert” bulk of the atmosphere is no exception and is known to radiate in the FAR infrared.

      Other commenters have already called attention to the gross inadequacy of the blackbody depiction of heat transfer from the surface in the face of various nonradiative mechanisms involved. What physical oceanographers have known for nearly half a century is that, under a wide range of measured conditions, heat transfer by evaporation from the ocean surface exceeds all other mechanisms COMBINED. Kiel and Trenberth’s cartoon depiction solely of “evapotranspiration” is an egregious misrepresentation of geophysical reality.

  14. Enjoyable presentation. It brings to mind several questions

    1) NL uses Hadcrut3 for the temperature record from the 1800s. Hadcrut3 is an adjusted record. I would like to know what his ECS and TCR are using unadjusted temperature records. My guess is that a majority of his calculated ECS and TRC comes from adjustments.

    2) TSI is a poor measure to use in looking at the potential effects of solar activity on the earth’s climate. The modern solar maximum sticks out like a sore thumb in the sunspot record, though TSI doesn’t change much.

    3) We know that oceans play a huge role in warming and cooling the atmosphere. If you look at unadjusted temperature records for the US and arctic ice extent, it seems clear that the AMO and other ocean currents play a large role in temperature. The satellite temperature record corresponds to a warm phase of the AMO. If the AMO rolls over into a cool phase and we see a temperature decline as we see in the unadjusted records of the US land temperatures, the satellite record will look very different in a decade or so.

  15. Mathematically, determining climate sensitivity to CO2 emissions is critically important, but politically it’s irrelevant to determining appropriate goals and strategies for managing climate risk.

    There will always be calls to increase taxes, enact wealth transfers, and to build out solar and wind power. Updated estimates for climate sensitivity will update the models, but we will never be found to be doing enough. Climate sensitivity is just one of several factors determining where the goalposts are set.

  16. Excellent presentation on what Nick is working on and his view of the issue. It helps filling the background for his on line-comments. Important points about his starting point; 1, all the warming is assumed to be due to CO2 2. the start point for the warming is 1850 and the total warming is 1.8-2.0°C. If so we are already more than half way there. I would ask if he has looked at balloon radiosonde data which I am given to understand show a reduction in high altitude water vapor over time, indicating a negative water vapor feedback rather than a positive one. In any case keep up the good work, much appreciated.

  17. I disagree, the mistake is to say he accepts the warmist position that CO2 will cause warming but that the figure will be less. The sceptical position has to be that this position is wrong and that is what accounts for the difference between predicted and measured variables.

  18. Nic Lewis’s problem with his ECS, just like the IPCC’s, is he still doesn’t know what the the natural vs GHG warming relative contributions are to the total warming 1870-present.

    The total warming could just as validly be 90% natural and anthro-GHG @ 10%. Using the adjusted HADCRUT tells us nothing but what the adjustments have been. And when the synthetic adjustments (Adjusted – Raw) vs CO2 rise are plotted as Tony Heller has done, the curtain is pulled back, and the scam is revealed.

  19. Title is:
    50 thoughts on “How sensitive is the climate to greenhouse gases?”

    that would be plural “gases”

    I’m coming up on Time mark 15:00 I want to see if he tells us what the climate sensitivity of methane is.

  20. “Nic Lewis disputes necessity for zero emissions in 2050 …’.
    Not only unnecessary but impossible.

  21. 2050 seems to have been adopted as the cult’s ‘new beginning’, the arrival of a carbon-free utopia.
    To the young 2050 seems far in the future but it’s only thirty years away.
    Thirty years ago the world didn’t look a lot different to how it looks today.
    There have been advances in computer power and their penetration into everyday life, medical advances and the like and certainly some places like Beijing and Dubai look a lot different but there are still Boing 747s flying, physical hardware advances have been generally are marginal.
    The cult members have no idea of scale, the very idea of zero emissions by 2050 is preposterous.

  22. I am hearing impaired so if anyone has a link to a version of this video which has closed captioning I would appreciate the information. I can understand a lot of what is said but I always miss many key words.
    Thank you

  23. There is an extension for Chrome Browser that will make Close Caption text of Youtube and Netflix.
    Substital – Have not used it may be worth a try.

  24. “How sensitive is the climate to greenhouse gases?”

    Poor old climate science. The question itself does not bear close examination.

    What is “the climate”?
    Perhaps some running 30 year arithmetic mean of an ill-defined physical parameter based on some arbitrary choice of idiosyncratic temperature measurements? And in a system where in the real world there will never even be a steady state, much less something ever approaching an equilibrium?:

    When one can’t even define the question meaningfully, all answers are moot. But the high priests computer modellers of integrated weather are probably quite happy with that state of affairs as long as the funding stream continues spurting hot.

  25. Nick Lewis forgot a few factors worth mentioning in support of his conclusions on policy:
    1. The warming observed has been mostly at upper latitudes, during their respective winter months. Most of the people don’t live there.
    2. The planet is greening at a rate not seen previously by mankind. I missed where he accounts for that.
    3. No mention of the fact that the peak temperatures occurred due to El Ninos, and global temperatures paused when the ENSO cycled otherwise. Mention of decadal ocean oscillations was also omitted.

    • I will retract the ocean oscillation statement because he did discuss the absorption of heat by the oceans, just not the release of heat by same.

      Henry’s law of gas absorption might have also been discussed relative to ocean sinking of GHGs.

  26. 1.) Lewis might actually believe the recent AGW temperature data that he shows in his Climate Model Spaghetti Graph (no warming pause…but there has been a 20 year pause according to satellite and balloon records)…but he would employ THEIR data even if he didn’t believe it in order to avoid “denier” status (by a few microns). In this exercise he’s able to defend a significantly lower Carbon Sensitivity while using their fudged data.
    2.) Lewis mentions positive water vapor feedback (with increasing temperature – warmer air CAN hold more moisture) without mentioning that atmospheric water content is measurable and is not increasing. And consequently, there is no hot spot “fingerprint” of AGW in the tropical mid-troposphere.
    3.) Lewis mentions the costs of warming as if there are a bunch of obvious climate associated costs. There isn’t any data showing net rising costs from climate change as we recover from the devastating LIA. Enumerating the benefits would be easy.

    I’m pointing out here some of what it takes to remain respectable enough in Science today to still get published.

    This is what happens when our institutions break down and truth and facts no longer hold the power that they should.

    This has the same smell as the abuse of power exercised by the Church in Europe over most of the last millennium. Hopefully circumstances will shortly allow for a Science Reformation. I hope we don’t have to suffer millions of casualties during this Inquisition.

  27. Isn’t the use of the word “greenhouse” in terms of warming wrong with regards to CO2?

  28. The “airborne fraction” and “transient climate response to cumulative emissions” are not supported by empirical evidence and that in turn means that carbon budgets are not supported by empirical evidence either.

    Airborne fraction: (2 links)

    Transient Climate Response to Cumulative Emissions (2 links)

    Carbon Budgets (1 link)

  29. I love it. At ~5:30, he admits that you have to go along with the “assessment” that humans cause ’50 to Over 100%’ of the warming to be PUBLISHED. In the next breathe, he dismisses that you need evidence to prove that warming is due to other causes. If you can’t determine what is ‘other’, how the hell do you know what is ‘manmade’. In a few seconds, you see that you must agree to baseless facts just to get a seat at the table.

  30. How about aerosols cooling he earth.
    After Pinatubo 1991 the cooling was obvious for more than a year.
    It released 20 M tons SO2 to the air.

    And how about warming by reducing the release of SO2?
    Since 1980 the reduction of SO2 is from 145M to 100 M tons to 2010.

    It could explain the solar Brightening , in Sweden we have 17% more sun/less cloud and a energy budget going from 900 KWh/m2 and year to 1000 KWh/m2 and year.
    What else could have given us more sun?

  31. Nic Lewis,
    By just looking at temperature data in last 150 years, how do you know how much warming is man-made vs. natural? You have to look at TOA radiative flux changes before you can blame CO2 for temperature changes. Lindzen and Spencer studied this independently. They both found strong negative feedback. It means TCR less than 1 K per 2x CO2. Read their papers. IMO they are the most important papers on climate sensitivity.

  32. Nic Lewis explains that it’s possible that solar forcing is more influential than we currently understand but there isn’t enough evidence to quantify it. He’s correct on this. If he starts introducing guesswork into his analysis then it will not be taken seriously.

    Lindzen and Spencer could be right and TCR might be no more than 1K per 2xCO2. On the other hand, Nic Lewis estimate of 1.4 k could be right. If I had to put money on it I’d back Nic to be nearer the mark.

    • As he said … I’m not convinced. His whole presentation is about effects of CO2, yet there is no evidence that CO2 plays any significant role at all in the changes in atmospheric temperature. He seems to have bought into the GHG theory that GHGs are the control knobs of climate. There simply is no evidence of such. In contrast, the data are pretty convincing that it is the ocean SST that determines the atmospheric temp above, and there is NO EVIDENCE that CO2 warms the ocean SST.

      I was trying to poke holes in my thoughts and wandered over to wonder boy
      Gavin Schmidts site, where he had a post that talked about a study of skin temperature as a function of LW rad. As he notes, since they couldn’t do a real experiment on the subject, they took a proxy, skin temp on cloud vs clear, with the thought that cloudy days have more LW rad. They laughingly found a difference of some .002C change with a 100W/m2 increase in DWLW from clouds. I would ask, what about evaporation. We know it is evaporation that cools the skin layer, so a slight decrease in evaporation due to less SW warming as results of clouds, could just as easily be the culprit. Further, if a 100W/m2 DWLR change is seen from clouds, vs the 1.7W/m2 increase from a change in CO2 … errr .that doesn’t speak well of CO2s ability to do squat.

      IMO … Spencer and Lindzen, and Nic Lewis are wrong. the TCR is more towards ZERO … like maybe .3 or .4, or maybe even zero itself. I’ve still seen absolutely NO convincing evidence that CO2 is a big enough player in the Climate System to amount to squat.

    • Lewis is looking only at the effect (temperature change) and an inferred cause (atmospheric CO2) that does not correlate well with the effect (1910-1940 warming, 1940-1977 cooling, 2000-2015 pause)

      Lindzen and Spencer are looking at the effect and the proximate cause (radiative flux). IMO that is more scientific. Lewis, you studied physics at Cambridge, don’t you agree you should be looking at radiation physics not just poor correlations?

  33. As he said … I’m not convinced. His whole presentation is about effects of CO2, yet there is no evidence that CO2 plays any significant role at all in the changes in atmospheric temperature.

    So the emission spectrum graphs which clearly show a CO2 funnel centred at around 667 cm-1 don’t suggest some effect?

    Actually Nic Lewis’s presentation is more about showing that the models are running too hot. To do this he needs to use the same assumptions that the models use.

    IMO … Spencer and Lindzen, and Nic Lewis are wrong

    Right Spencer is wrong … Lindzen is wrong …. Lewis is wrong . To that list you’ll need to add several more noted sceptical scientists including Jack Barrett who has spent a lifetime studying the chemistry and spectroscopy of small molecules, Does it ever occur to you that you might be one that’s wrong.

  34. If the solar wind had not weakened from the mid 1990’s, the AMO and Arctic would not have warmed, low cloud cover would not have declined, surface wind speeds over the oceans would not have increased, and lower troposphere water would not have increased so. Though if you substitute oceanic negative feedbacks with CO2 forcing, you could go to week long conferences at splendid locations!

Comments are closed.