What it would take to persuade me that current climate policy makes sense
Guest post by Matt Ridley
I have written about climate change and energy policy for more than 25 years. I have come to the conclusion that current energy and climate policy is probably more dangerous, both economically and ecologically, than climate change itself. This is not the same as arguing that climate has not changed or that mankind is not partly responsible. That the climate has changed because of man-made carbon dioxide I fully accept. What I do not accept is that the change is or will be damaging, or that current policy would prevent it.
For the benefit of supporters of climate change policy who feel frustrated by the reluctance of people like me to accept their assurances, here is what they would need to do to change my mind.
1. I need persuading that the urban heat island effect has been fully purged from the surface temperature record. Satellites are showing less warming than the surface thermometers, and there is evidence that local warming of growing cities, and poor siting of thermometers, is still contaminating the global record. I also need to be convinced that the adjustments made by those who compile the global temperature records are justified. Since 2008 alone, NASA has added about 0.1C of warming to the trend by unexplained “adjustments” to old records. It is not reassuring that one of the main surface temperature records is produced by an extremist prepared to get himself arrested (James Hansen).
2. Despite these two contaminating factors, the temperature trend remains modest: not much more than 0.1 C per decade since 1979. So I would need persuading that water vapour will amplify CO2’s effect threefold in the future but has not done so yet. This is what the models assume despite evidence that clouds formed from water vapour are more likely to moderate than amplify any warming.
3. Nor am I convinced that sulphate aerosols and ocean heat uptake can explain the gap between model predictions and actual observations over the last 34 years. Both are now well understood and provide insufficient excuse for such an underperformance. Negative cloud feedback, leading to total feedbacks being modest, is the more plausible explanation.
4. The one trend that has been worse than expected – Arctic sea ice – is plausibly explained by black carbon (soot), not carbon dioxide. Soot from dirty diesel engines and coal-fired power stations is now reckoned to be a far greater factor in climate change than before; it is a short-lived pollutant, easily dealt with by local rather than global action. So you would need to persuade me that this finding, by explaining some recent climate change, does not further reduce the likely sensitivity of the atmosphere to carbon dioxide. Certainly, it “buys time”.
5. Even the Met Office admits that the failure of the models to predict the temperature standstill of the last 16 years is evidence that natural factors can match man-made ones. We now know there is nothing unprecedented about the level and rate of change of temperature today compared with Medieval, Roman, Holocene Optimum and other post-glacial periods, when carbon dioxide levels did not change significantly, but temperatures did. I would need persuading that natural factors cannot continue to match man-made ones.
6. Given that we know that the warming so far has increased global vegetation cover, increased precipitation, lengthened growing seasons, cause minimal ecological change and had no impact on extreme weather events, I need persuading that future warming will be fast enough and large enough to do net harm rather than net good. Unless water-vapour-supercharged, the models suggest a high probability of temperatures changing less than 2C, which almost everybody agrees will do net good.
7. Nor is it clear that ecosystems and people will fail to adapt, for there is clear evidence that adaptation has already vastly reduced damage from the existing climate – there has been a 98% reduction in the probability of death from drought, flood or storm since the 1920s, for example, and malaria retreated rapidly even as the temperature rose during the twentieth century.
8. So I cannot see why this relatively poor generation should bear the cost of damage that will not become apparent until the time of a far richer future generation, any more than people in 1900 should have borne sacrifices to make people today slightly richer. Or why today’s poor should subsidise, through their electricity bills, today’s rich who receive
subsidies for wind farms, which produce less than 0.5% of the country’s energy.
9. Indeed I will need persuading that dashing to renewables can cut emissions rather than make them worse; this is by no means certain given that the increased use of bioenergy, such as wood or corn ethanol, driven by climate policies, is indeed making them worse.11 Meanwhile shale gas use in the USA has led to a far greater cut in emissions than
any other technology, yet it is opposed every step of the way by climate alarmists.
10. Finally, you might make the argument that even a very small probability of a very large and dangerous change in the climate justifies drastic action. But I would reply that a very small probability of a very large and dangerous effect from the adoption of large-scale
renewable energy, reduced economic growth through carbon taxes or geo-engineering also justifies extreme caution. Pascal’s wager cuts both ways.
At the moment, it seems highly likely that the cure is worse than disease.
We are taking chemotherapy for a cold.
Full paper with graphs and references here
Related articles
- A climate of scepticism (wattsupwiththat.com)
- Matt Ridley responds with a “sleight of hand” (scienceblogs.com)
- Matt Ridley’s actual response (wattsupwiththat.com)
- The Lukewarmer’s Way
Greg House says (January 31, 2013 at 3:52 pm): “Gary, generally science and what a scientist said or did not say are 2 different things.”
Generally a scientist says exactly what the science (his experiment) supports, no more, no less. Surely you’re not saying Wood was unscientific? Or is this just your way of acknowledging that Wood himself did not share your conclusion? If so, this is progress, I suppose.
“Therefore twisting Wood’s comments on his experiment can not scientifically devalue his experiment.”
Um, Greg House claims much more than his hero Wood can claim, but I’m the one twisting his words??? Please note, Greg, that Wood himself “devalued his experiment” when he wrote “I do not pretend to have gone very deeply into the matter”. Greg, do you pretend he did?
“Second, ‘scarcely a difference of one degree’ is in fact close to zero and it is negligible, anyway in context of alleged 33 degrees warming by back radiation from ‘greenhouse gases’.”
So you acknowledge that the so-called “greenhouse effect” (SCGE) is real, and are just arguing about its magnitude? This is also progress, though you’re comparing apples (the “inside”) to oranges (the “outside”).
“Wood did not model a greenhouse…”
Um, he most certainly tried to. Quoting (not “twisting”) Wood, “As a matter of fact I am of the opinion that a greenhouse made of a glass transparent to waves of every possible length would show a temperature nearly, if not quite, as high as that observed in a glass house.” That’s what he was testing, and that’s what he modelled. Greg, if Wood didn’t model a greenhouse:
(1) What did he model, if anything (please justify your choice), and
(2) How can you apply his results to anything other than whatever he did model?
Note that he certainly didn’t model the atmosphere, which has no walls (black or otherwise), no cotton stuffing, no glass or salt cover, is much, much bigger than a real or model greenhouse, has much, much more convection than a real or model greenhouse, and about half of which at any one time receives no sunlight.
“By the way, thank you for referring to greenhouses this time, because there is a funny thing about how warmists have adjusted their “greenhouse effect” notion and claim now that it is not trapped/back radiation that warms a greenhouse, it is suppressed convection, but at the same time back radiation does warm earth surface outside greenhouses.”
Thank you for “twisting” both the “warmist” and CAGW skeptic views. Both actually agree that reduction of convection generally outweighs IR “trapping” in raising greenhouse temperature. Every one of the experiments we’ve checked (Wood, Pratt, Nahle, high tunnels) supports this. But did you ever ask yourself how these results apply to the whole earth/ocean/atmosphere, which is pretty much the opposite of a greenhouse? You said it yourself: the greenhouse is “inside”, the atmosphere is “outside”! Wood only modelled the “inside”.
“You see, Gary, you can start here or you can start there, any way warmism still looks very much like a hoax.”
It does, but not because of Wood’s poorly documented simplistic one-off daylight backyard experiment which, at best, is relevant only to greenhouses. 🙂
Out of sincere curiosity, Greg, if you ever became convinced that the SCGE actually raises Earth’s surface temperature roughly 30 degrees C compared to a hypothetical Earth without so-called “greenhouse” gasses, would you automatically become a “warmist”?
jae says (January 31, 2013 at 7:28 pm): “THEN WHY DOESN’T THE LAPSE RATE EQUATION (rate = g/Cp) DEPEND ON “BACKRADIATION”?????
Simple question, but still no answer after years of asking….”
Out of curiosity, why do you think (if I understand correctly) the adiabatic lapse rate equation should depend on any kind of radiation? Looking at the sea level solar spectrum
http://en.wikipedia.org/wiki/File:Solar_Spectrum.png
I see that several gasses (CO2, O2, H2O, O3) absorb at least some incoming solar radiation, yet your equation doesn’t include this “front” radiation. Do you think it should, or am I misunderstanding you?
davidmhoffer says:
January 31, 2013 at 6:25 pm
“dropping thread.”
——————————————————–
Off to find a fresh spherical chicken I expect…
Konrad:
Your post at January 31, 2013 at 6:25 pm suggests that davidmhoffer has dropped the thread because he is “off to find another spherical chicken”.
As an onlooker, I have a different conclusion; i.e.
his head is hurting from banging it against the ‘brick wall’ of willful ignorance and deliberate stupidity displayed by those who dispute the existence of the atmospheric GHE.
I never contributed to the head-banging because I know that ‘brick wall’ is buttressed by so much prejudice that – as this thread demonstrates – it cannot be breached by logic, evidence and reason.
Richard
richardscourtney says:
February 1, 2013 at 1:55 am
“…willful ignorance and deliberate stupidity displayed by those who dispute the existence of the atmospheric GHE.”
————————————————————————————————–
Richard,
I dispute the radiative GHE on the basis of empirical experiment, not on the basis of “willful ignorance and deliberate stupidity”.
There is a greenhouse effect on earth, caused by N2 and O2 being poor radiative gases. This effect is moderated by the radiative gases in our atmosphere, primarily H2O.
The failed hypothesis of the radiative GHE only looks plausible when you fail to model the atmosphere correctly. The “basic physics” of the “settled science” is in error. How many of the “Do nots” of modelling a moving atmosphere were used in supporting the claims of a radiative GHE?
– Do not model the “earth” as a combined land/ocean/gas “thingy”
– Do not model the atmosphere as a single body or layer
– Do not model the sun as a ¼ power constant source without diurnal cycle
– Do not model conductive flux to and from the surface and atmosphere based on surface Tav
– Do not model a static atmosphere without moving gases
– Do not model a moving atmosphere without Gravity
The history cannot be re-written in the age of the Internet. The evidence that the critical role of radiative gases in convective circulation was not correctly modelled in the radiative GHE calculations cannot be erased. When this is taken into account, the NET effect of radiative gases in our atmosphere is cooling.
Richard, I will ask you directly, Do radiative gases play a critical role in convective circulation below the tropopause? Is the answer –
A. No
B. yes
C. Bafflegab
D. Unicorn
Konrad.:
re your question to me at February 1, 2013 at 2:34 pm
Answer: B (yes) in two important ways.
Radiative gases warm non-radiative gases (N2 and O2) by collisional de-excitation and they warm the surface radiatively thus adding to the conductive warming of gases in contact with the surface. Warmed gas rises (i.e. convection).
Now, I don’t intend to waste time discussing whether basic radiative physics is correct when it is.
So, I also am “signing off” from this thread.
Richard
Davidmhoffer wrote on 1/29/2013 8:22 pm;
………. Did not quote here verbatim to save space.
Yes indeed the IR radiation does not slow down, but it is absorbed by the water vapor (remember
water vapor is the MOST powerful Greenhouse Gas) and thereafter the speed at which the energy flows (via conduction, convection) is indeed slowed.
And the SB law only predicts the distribution of energy versus wavelength, it says nothing about the speed at which energy flows through a complex system where conduction, convection and radiation are all happening to different degrees in parallel.
And yes indeed I learned all about the SB law in school and apply it every day to make verified predictions of how a real system responds to real world stimulus.
Cheers, Kevin.
richardscourtney says:
February 1, 2013 at 3:07 pm
Now, I don’t intend to waste time discussing whether basic radiative physics is correct when it is.
—
Well, Konrad has convinced me. The only thing basic about AGW radiative physics is that it’s basically wrong.
CO2 cools the surface by radiating at altitude what would otherwise be radiated from the surface. If there were no IR gases on earth the surface would be much warmer. Count me in as luke-cooler 🙂
Eric Barnes says (February 1, 2013 at 4:13 pm): “CO2 cools the surface by radiating at altitude what would otherwise be radiated from the surface. If there were no IR gases on earth the surface would be much warmer.”
At this point I don’t expect to change anyone’s mind, but I can’t help referring Eric to Willis Eschenbach’s excellent “Glass Planets” article on WUWT:
http://wattsupwiththat.com/2010/11/27/people-living-in-glass-planets/
The case of an Earth with no so-called “greenhouse” gasses in its atmosphere is very much like Willis’s Figure 2, except the transparent non-radiating shell is in contact with the surface and has the same temperature. Note that this doesn’t warm the surface.
The radiating shell in his Figure 4 does indeed “cool” the model planet, but it also “warms” the planet because it radiates both “out” and “in”. Note that the planet without a radiating shell (or with a non-radiating shell) only radiates “out”.
For a different look at a non-radiating atmosphere, I recommend Dr. Roy Spencer’s article here:
http://www.drroyspencer.com/2009/04/in-defense-of-the-greenhouse-effect/
Gary Hladik says:
February 1, 2013 at 10:45 pm
I don’t see how Willis’ example brings clarity to the question of whether IR active gases warm or cool the planet. It’s strays from the heart of the matter as I understand it.
Konrad’s example is to the point.
Consider Earth A without any IR gases compared to Earth B with all IR gas.
All Solar energy “must be radiated from the surface” of Earth A. Convection and conduction occur, but what goes up must come down and will heat the surface.
Earth B can effectively use convection and conduction *and* IR gas to radiate at height (away from the surface).
To me, that’s as clear as it get’s that IR active gases cool the surface of the planet (or any planet for that matter).
Konrad has said it before and I’ll repeat it. The true greenhouse gases are the NON-IR gases.
I’ll read Willis and Dr. Spencers posts again They aren’t doing much for me at the moment.
Eric Barnes says (February 2, 2013 at 12:55 pm): ‘All Solar energy “must be radiated from the surface” of Earth A. Convection and conduction occur, but what goes up must come down and will heat the surface.’
As Dr. Spencer writes, since the atmosphere doesn’t cool at the top (it doesn’t radiate), vertical convection ceases when the atmosphere is well mixed to the same temperature as the surface. The atmosphere, heated by conduction from the surface, can’t conductively heat the surface to a higher temperature. The surface radiates as in Willis’s Figure 2, whether the transparent non-radiating shell/atmosphere is in contact with the surface or not.
“Earth B can effectively use convection and conduction *and* IR gas to radiate at height (away from the surface).”
Correct, but remember the radiating atmosphere/shell radiates both “out” and “in”; the transparent shell/atmosphere doesn’t. In a manner of speaking, the surface gets a “rebate” on its radiated energy that it doesn’t get from the transparent shell/atmosphere.
Konrad’s insights also provides an explanation in my mind to another puzzle of the temperature record.
Even as surface temperatures have warmed, the number of all time highs have dropped (for long lived stations).
http://stevengoddard.wordpress.com/2012/08/10/a-simple-proof-that-the-1930s-were-hotter/
The greater concentration of CO2 in the thermosphere of today relative to the past means the surface is more effectively cooled now vs. then. Any indcident radiation on CO2 above the surface can be radiated directly to space or conducted to gases that are moved by convection to TOA and subsequently radiated to space (thus bypassing the surface).
Gary Hladik says:
February 2, 2013 at 1:27 pm
“As Dr. Spencer writes, since the atmosphere doesn’t cool at the top”.
He doesn’t say this, and it is factually incorrect at the TOA. If you’re talking about something else I can’t make it out.
I still fail to see how the model Willis describes has any bearing on whether IR gases warm or cool the earths surface.
Eric Barnes says (February 2, 2013 at 1:44 pm): “The greater concentration of CO2 in the thermosphere of today relative to the past means the surface is more effectively cooled now vs. then.”
Don’t forget, Eric, if CO2 is radiating more “out” of the system, it’s also radiating more “into” the system.
Gary Hladik says:
February 2, 2013 at 2:42 pm
Don’t forget, Eric, if CO2 is radiating more “out” of the system, it’s also radiating more “into” the system.
—
More to the surface than transparent N2 or O2? No.
Gary Hladik says:
February 1, 2013 at 10:45 pm
—————————————————————————————
Gary,
This statement “except the transparent non-radiating shell is in contact with the surface and has the same temperature. Note that this doesn’t warm the surface.” is entirely wrong.
Lets review the “do nots” of atmospheric modelling –
1. Do not model the “earth” as a combined land/ocean/gas “thingy”
2. Do not model the atmosphere as a single body or layer
3. Do not model the sun as a ¼ power constant source without diurnal cycle
4. Do not model conductive flux to and from the surface and atmosphere based on surface Tav
5. Do not model a static atmosphere without moving gases
6. Do not model a moving atmosphere without Gravity
To claim that a non-radiative atmosphere will have the same temperature as the surface you would need to committed the following “do nots”. 2,4,5 & 6.
While the surface under a non-radiative atmosphere may have a lower Tmin, the temperature of hot air rising into the atmosphere is set by Tmax Not Tmin or Tav. This simple empirical experiment you can build yourself –
http://i48.tinypic.com/124fry8.jpg http://tinypic.com/r/zmghtu/6 http://tinypic.com/r/15n0xuf/6
demonstrates this point very clearly. It also demonstrates the critical importance of cooling at altitude to convective circulation and atmospheric temperatures Box 2 always runs hotter, build the boxes big enough to minimise the slow effects of gas conduction and the temperature of Box 2 will rise close to surface Tmax.
I have comented previously on this thread about the mistake of modelling the atmosphere as a single layer or modelling an atmosphere without moving gases. You are making the same mistake. In an gas column in a gravity field, cooling at the base of the column is less effective than cooling at the top of the column. A lower Tmin under a non-radiative atmosphere will not lead to lower atmospheric temperatures. Gravity keeps cooler air at the surface during the night minimising conductive flux. Gravity keeps cooler air at the surface during the day maximising conductive flux.
Here is another simple empirical experiment that you can build and run yourself that demonstrates this –
http://i49.tinypic.com/akcv0g.jpg
What you see in the image are two small EPS foam tubes. Internal volume is 75 x 75mm by 200mm high.
Tube 1 has a top with cling film replacing the foam.
Tube 2 has a base with cling film replacing the foam.
Each tube has a battery pack and a small 5V computer fan blowing across the outside of the cling film.
Tube 1 has small legs on one side to tilt it to around 5 degrees off vertical. This helps convective flow start against the friction of the internal walls.
Tube 2 has 50mm legs to allow its fan to move air freely across the cling wrap
You will note that there are multiple thermometer probe entry points in each tube.
The experiment has been scaled to fit in a refrigerator. Over 200mm the speed of gas conduction is well out of scale to a real atmospheric column, but the imbalance in conductive energy flows between the two tubes is still very clear.
To conduct the experiment first equalise the internal temperature of each tube to room temperature by turning each tube cling film down and running the fans for 15 minutes. Use a thermometer probe position equal distance from the cling film for each tube.
Now orientate the tubes so tube 1 has cling film at the top and tube 2 has cling film at the base. Place them on a shelf in a refrigerator with the fans running and close the door with the thermometer outside. The fans ensure air in the refrigerator does not stagnate need the cling wrap cooling zones on each tube. If your refrigerator has wire shelves, place a plate under each tube.
Use the probe differential button on the thermometer to observe the temperature differential between the tubes develop as they cool from room temperature. Due to the small size of the tubes compared to the speed of gas conduction, maximum differential should be achieved in 2 minutes and decrease thereafter.
Remove the tubes from the refrigerator and allow them to equalise to room temperature again, move the thermometers to new positions and repeat the cooling run. Do this a number of times to build up a picture of the temperature differential at various distances from the cling wrap in each tube at the 2 minute mark.
With a room temperature of 25C and a refrigerator temperature of 7C here are some typical temperature differentials at the 2 minute mark
175mm from the cooling surface – tube 1 2.0C cooler than tube 2
100mm from the cooling surface – tube 1 1.3C cooler than tube 2
25mm from the cooling surface – tube 2 0.3C cooler than tube 1
Tube 1 with the cooling surface at the top cools faster. This is because cooling from the top of a gas column in a gravity field sets up a convective flow bringing the hottest gases in contact with cooling surface. This maximises temperature differential at the cooling interface and maximises conductive energy flow. In box 2 convection does not occur and gravity keeps the coolest gas in contact with the cooling interface. This minimises temperature differential at the cooling interface and minimises conductive energy flow.
The experiment gives clear results even when compromised by being scaled to fit in a domestic refrigerator. If you want truly dramatic results try insulated tubes 2m tall in a commercial cool room.
Now if instead you want the garbage AGW math to work you can do that too. You simply need to remove the factor not modelled in the AGW calculations, which of course is GRAVITY. Simply turn the boxes on their side when placing them in the refrigerator and they will cool at the same rate.
Gary, you will note that some other “lukewarmers” have shamelessly fled rather than debate. You can do as they have done, you can type, link and cut&paste or do your own work. I highly recommend that you drop the mouse and step slowly away from that keyboard. Do the empirical experiments. You will find –
– Without convective circulation below the tropopause our atmosphere heats.
– radiative gases are critical to convective circulation below the tropopause
– radiative gases cool our atmosphere at all concentrations above 0.0ppm
richardscourtney says:
February 1, 2013 at 3:07 pm
“Now, I don’t intend to waste time discussing whether basic radiative physics is correct when it is.
So, I also am “signing off” from this thread.”
————————————————————————————
[snip. That is a sure way to make sure no one ever disengages. — mod.]
In answering “B” Richard got the right answer, but his qualification was plain wrong. Radiative gases also play vital role in convective circulation by removing energy from the atmosphere. Te simple experiment you all can try –
– get a large glass container of hot water and mix a ¼ teaspoon of finely ground cinnamon into it.
– wait until Brownian motion slows till the suspended particles are barely moving.
– now suspend a beer can full of ice water in the top 50mm of the hot water to one side of the clear container.
– watch as convective circulation develops in the container.
This experiment demonstrates convection flow driven by the removal of energy from a fluid column in a gravity field. Radiative gases do this in our atmosphere.
To those still reading this thread I would advise that I do not side with the “slayers”, I base my scientific argument against the radiative GHE hypothesis on the basis of my own empirical experiments. I am not linking to or cutting and pasting the work of others. Despite intentional mis-characterisations, I do accept that radiative gases in our atmosphere intercept out going IR from the surface. I do accept that the atmosphere radiates IR back to the surface. I contend however that these gases in our atmosphere have a far more important role in radiating IR to space at altitude. Without this, convective circulation under the tropopause would stall and cease and our atmosphere would heat dramatically. Radiative gases therefore cool our atmosphere at all concentrations above 0.0ppm.
Readers will note the unseemly haste with which “Lukewarmers” Richard and David fled the thread. They barely lasted two rounds. A sorry display, but it illustrates an important point, FEAR.
Sceptics by all measures are more technically and scientifically educated then AWG believers. However few lukewarmers are willing to challenge the “basic Physics” of the “settled science”. The Knights of Consensus clearly failed to model gravity, or its effects in mobile gaseous atmosphere. Yet lukewarmers will not challenge. It is important to note here that there are more “sceptic” lukewarmers who claim to understand and accept the radiative GHE hypothesis than there are AGW believers who would claim the same. It is the FEAR of going against the herd or tribe that holds these sceptics in thrall. In the FEAR of seeming foolish, lukewarmers are exhibiting the ultimate in stupidity. This is how they planned to trap you and you fell for it. Lukewarmers do not want to admit that they do not understand the math used to support the radiative GHE hypothesis for FEAR of looking foolish. You do not need to understand the math, you only need to recognise that it has not been applied to discrete moving air masses and that it has not been applied iteratively.
What readers should understand is that the Knights of Consensus, Nick Stokes, Joel Shore, Jim D, and of course S.Mosher (who has shed his false tabard at JC), have known for years that the radiative GHE model they were defending was false. These guys are smarter than “Lukewarmers” such as Richard and David, they did not debate directly but used a proxy. In a thread at the Talkshop lasting over 600 comments the AGW position pitted against my argument lost and lost badly. They gave it all they had and lost.
The Knights of Consensus now have new standing orders. “Do not engage.” No matter.
For those quisling lukewamers, a quote from Frank Herberts “Dune” –
“I must not fear. Fear is the mind-killer. Fear is the little-death that brings total obliteration. I will face my fear. I will permit it to pass over me and through me. And when it has gone past I will turn the inner eye to see its path. Where the fear has gone there will be nothing. Only I will remain.”
Grow a spine sheeple!
[snip. That is a sure way to make sure no one ever disengages. — mod.]
I accept the [Snip], Anthony’s blog, Anthony’s rules. However in my limited defence I would say that while non conductive to further rational scientific debate….He deserved it! He sooooo deserved it…;)
Gary writes: “As Dr. Spencer writes, since the atmosphere doesn’t cool at the top”.
Eric writes: “He doesn’t say this, and it is factually incorrect at the TOA.
The top of a non-radiating atmosphere doesn’t cool because it has no way to do so. The top of a radiating atmosphere cools by–surprise!–radiation.
Gary writes: “Don’t forget, Eric, if CO2 is radiating more “out” of the system, it’s also radiating more “into” the system.”
Eric writes: “More to the surface than transparent N2 or O2? No.”
In a non-radiating atmosphere, nothing radiates to the surface. If you mean conduction, the surface conductively heats the atmosphere, which can’t then conductively heat the surface any hotter.
Eric Barnes says (February 2, 2013 at 2:35 pm): “He doesn’t say this, and it is factually incorrect at the TOA. If you’re talking about something else I can’t make it out.”
Dr. Spencer doesn’t say it in the article I referenced. Sorry. He says it in this article:
http://www.drroyspencer.com/2009/12/what-if-there-was-no-greenhouse-effect/
Konrad. says (February 2, 2013 at 8:10 pm): “I contend however that these gases in our atmosphere have a far more important role in radiating IR to space at altitude. Without this, convective circulation under the tropopause would stall and cease and our atmosphere would heat dramatically.”
What about the surface of the planet?
Gary Hladik says:
February 2, 2013 at 10:35 pm
Thanks Gary.
This statement …
“Only the surface and a shallow layer of air next to the surface would go through a day-night cycle of heating and cooling. The rest of the atmosphere would be at approximately the same temperature as the average surface temperature. And without a falloff of temperature with height in the atmosphere of at least 10 deg. C per kilometer, all atmospheric convection would stop.”
doens’t make any sense to me. There would be strong heating at surface on the day side of the planet at lower latitudes (all heating is at surface, so the temperature differential is higher than an IR gas world, hence, stronger convection) and progressively less as you moved to higher latitudes. It also seems like Dr. Spencer does not consider the lapse rate is defined by gravity? Heated air would still rise *and* cool as it exchanged KE for PE as it climbed the gravity well. Once the heated air had climbed and cooled it would descend and heat on the return bringing that energy back to the surface. It would seem to make sense that a strong movement of air from tropics to poles (at height) and (poles to tropics at surface) would develop.
Once again. All radiative heating and cooling from the non-IR system in total must occur at the surface. Non IR gases ensure that all energy in the system eventually goes there. An IR gas world can cool from a much larger area and so it makes sense that the surface temperature on average *drops*.
Thanks again for the link.
Eric Barnes says (February 3, 2013 at 7:16 am): “(all heating is at surface, so the temperature differential is higher than an IR gas world, hence, stronger convection)”
Don’t forget that the top of the non-radiating atmosphere has no way to cool, so the best that convection can do is establish a temperature gradient equal to, not greater than the lapse rate. You don’t get more convection, you eventually get less. Conduction eventually erases even that temperature gradient, except for a layer near the surface which perpetually warms and cools as the planet rotates.
Gary Hladik says:
February 2, 2013 at 10:48 pm
“What about the surface of the planet?” [under a non radiative atmosphere]
—————————————————————————————–
Gary,
a very good question. Here is a simple diagram showing energy flux for SW IR and conduction in a non-radiative atmosphere for day and night over a desert –
– http://tinypic.com/r/5m01ac/6
The reason for the difference in size of the purple arrows for conduction is explained by the insulated tubes experiment I posted earlier.
The land surface of a planet under a non radiative atmosphere would have a lower Tmin and lower Tav. This effect would be minimal over oceans as liquid water that is free to evaporatively cool does not have its cooling rate effected by DWIR. Over land this would result in severe temperature swings during a diurnal cycle in a few metres of air close to the surface. Night temperature inversion would be far more pronounced. Normally night temperature inversion is strongest on low wind nights and is broken up by “mechanical convection” on windier nights. However with deep vertical circulation in the atmosphere stalled, forces available to drive such wind would be limited. Wind may be limited to horizontal advection winds at dawn and dusk.
Essentially a non radiative atmosphere will run far hotter at most altitudes and most locations on the planet. Very close to the surface on land, extreme diurnal temperature swings would likely be experienced. This is currently what occurs in the driest desert regions under the current atmospheric conditions.
Gary, It should be noted that the diagrams I have posted only relate to a theoretical period shortly after the ability of the atmosphere to intercept or radiate IR was “switched off”. What would happen after that is far more extreme. Currently we have a troposphere which is cooled by radiative gases. Above this we have a stratosphere which is conductively cooled from below by the troposphere. This is evidenced by the lapse rate reversal. Above this is the thermosphere where extreme temperatures are the norm.
N2 and O2 do have a small ability to absorb electromagnetic radiation from UV to IR. Their ability to radiate this intercepted energy as IR is poor at low temperatures. Without radiative gases cooling the troposphere, the stratosphere and the upper regions of the atmospheric region formally known as the troposphere would slowly begin to superheat and expand. Much of the atmosphere could then be swept away by solar wind.
Radiative gases do not just keep the planet cool, they help the planet keep its atmosphere. Have a look around the solar system. Are there any planets or moons that have managed to retain an atmosphere without radiative gases?
What I am proposing may sound extreme after years of lies about radiative gases, but it is far more scientifically sound than the extreme claims of the AGW crowd. They are essentially claiming that adding radiative gases to the atmosphere will reduce its radiative cooling ability, an extraordinary claim. Extraordinary claims require extraordinary evidence. They have none. The “basic physics” of their “settled science” requires the atmosphere to be modelled as a single layer without gravity and moving gases. They have not just gotten the magnitude of the effect of radiative gases in our atmosphere wrong but critically they got the sign of the effect wrong. In light of this, the position of “Lukewarmer” is not a scientific position it is a political position.
Konrad. says (February 3, 2013 at 5:33 pm): “Here is a simple diagram showing energy flux for SW IR and conduction in a non-radiative atmosphere for day and night over a desert –
– http://tinypic.com/r/5m01ac/6
The reason for the difference in size of the purple arrows for conduction is explained by the insulated tubes experiment I posted earlier.”
I assume the two diagrams are not to scale, as the thermal conductivity of air at 40 degrees C is only about 12% greater than air at 0 degrees C.
http://www.engineeringtoolbox.com/air-properties-d_156.html
“The land surface of a planet under a non radiative atmosphere would have a lower Tmin and lower Tav. This effect would be minimal over oceans as liquid water that is free to evaporatively cool does not have its cooling rate effected by DWIR.”
I assume you’re saying this situation is only temporary, and would change even if the atmosphere weren’t stripped away, as otherwise you’re agreeing with your recently departed opponents.
“They are essentially claiming that adding radiative gases to the atmosphere will reduce its radiative cooling ability, an extraordinary claim.”
Why is it extraordinary? We agree that the addition essentially redirects some of the surface radiation back to the surface. The extraordinary claim is that the added energy won’t warm the surface. I think we’ve reversed the null hypothesis here. 🙂