Thursday, 31 December 2020

Can you believe in six impossible things before breakfast?

I've done a lot more Googling and reading up on ozone depletion theory since I stumbled across it a couple of weeks ago. It seems to be a very plausible and mercifully simple explanation why the troposphere (lower atmosphere) has warmed a bit and the upper atmosphere (stratosphere) has cooled a lot over the past forty years. It might be correct, it might be nonsense, but it does appear to be the most likely explanation and the most worthy of investigation and exploration.

Most of the hits you get if you search the terms 'ozone depletion' or 'stratosphere cooling' are Alarmist websites and blogs (for example Skeptical Science and Science of Doom), all of which greatly play down the effects of ozone depletion.

Nonetheless, stratospheric cooling is A Thing, and the Alarmists see themselves obliged to explain it in terms of CO2 and radiation (for no obvious reason).

Do your own reading up and make up your own mind, but IMHO, here are the six impossible, or at least mutually contradictory, things Alarmists have to believe before breakfast:

1. CO2 'traps' some of the infra red radiation (IR) emitted upwards by land, oceans and clouds in the troposphere

As a result, the troposphere warms. To believe this, you have to ignore the fact that radiation does not have a temperature and is not thermal energy. Radiation has to hit something first, cease to be radiation and be converted from radiation to thermal energy ('energy is not created or destroyed' etc). You also have to ignore the fact that the total IR emitted to space is equal to the total IR emitted by land, oceans and clouds (give or take a couple of per cent, depending which assumptions you make - nobody knows and it's impossible to prove or disprove either way).

And as a secondary result, there is less radiation going up into the stratosphere, so the stratosphere cools. To believe this, you have to ignore the fact that the stratosphere is warmed from above by UV-C and UV-B interacting with oxygen (O2) and ozone (O3). Accepted science is that the high energy UV radiation split molecules, so the energy is converted to chemical energy (endothermic reaction), and when O and O2 recombine to form O3, the chemical energy is converted to thermal energy (exothermic reaction). There appears to be little interchange of thermal energy (whether by convection or radiation) between troposphere and stratosphere. That is why the temperature falls to its lowest at the tropopause (the boundary layer between the two).

2. The effect of more CO2 is to push the 'effective emitting altitude' (henceforth abbreviated to EEA to save me typing it out in full every time) upwards

This is a more sophisticated Alarmist theory than simple 'trapping'. It dismisses the 'trapping' idea and says IR at certain frequencies can only escape to space if the CO2 above it is less than a certain threshold in terms of density. CO2 is a fairly constant proportion of the atmosphere all the way up (about 1/25 of one percent) but the density of the atmosphere goes down as you go higher, and so does CO2 density per unit volume. Only IR emitted (by CO2 itself, natch) at or above the EEA at which CO2 density (in terms of CO2 per unit volume) is at that certain threshold can get to space. So more CO2 means the EEA is at a higher altitude.

This theory seems to accept the gravito-thermal effect aka the lapse rate. It also assumes that temperature and hence IR emitted at the EEA is a constant, so mathematically, if the threshold is one-sixth of a km higher (so it goes up from 5km to 5.166r km, for example), the surface is warmer by one-sixth of 6.5 K/km = about 1 degree warmer.

OK, but going back to 1, if the EEA is the same temperature and is allowing the same amount of IR to pass through and up, then the same applies to the tropopause (about 10 - 12 km up on average). If the stratosphere is warmed from below (which isn't true anyway), the lowest layer of the stratosphere would remain the same temperature. Which it clearly isn't doing. And we have a problem with the initial assumption that IR emitted at the EEA or tropopause goes out into space (instead of warming the stratosphere above it).

3. More CO2 in the stratosphere means it can radiate more out into space

According to this theory, nothing except GHGs can emit radiation (well apart from land, oceans and clouds, obvs), and certainly not nitrogen or oxygen/ozone. So you could heat air up as warm as you wished, and an IR thermometer would not be able to read a temperature. So all that thermal energy would be 'trapped' in the stratosphere. Along comes some extra CO2, which absorbs the thermal energy, turns it into radiation and biffs it up and out into space, it being above the EEA.

Or maybe it biffs some down into the troposphere to warm it a bit more. Apart from the fact that the net transfer of energy by radiation only goes from warmer to colder, and how does this radiation battle its way down through the EEA, which is impassable for radiation from below?

Either way, there is a neat double think that CO2 can 'trap' more radiation in the atmosphere and also  emit more out into to space.

4. If 2 and 3 are true, then perhaps there are two EEA's?

Theory 2 is based on the fact the temperature falls as you go up through the tropopause. Push the EEA higher and that leads to surface warming. Perhaps Theory 3 is that there is a separate EEA for the stratosphere. If you push this higher, by reverse logic, everything below the new EEA cools down a bit?

5. The troposphere and stratosphere are in thermal equilibrium. Or not, as the case might be

If the temperature of the two layers tends to even out (by layers emitting radiation at each other), then we wouldn't see one warming and the other one cooling. So that blows a hole in Theory 1. Unless CO2 increases the lapse rate. Even though the main GHG, water vapour, reduces the lapse rate. On the other hand, Theory 2 assumes that there is a 'sort of' thermal equilibrium i.e. the temperature at the tropopause stays constant, but only a weak link, so below and above that altitude, each layer does its own independent thing. But if the stratosphere above does its own thing, is that not a tacit admission that it is warmed from above?

This obsession with radiation as the main form of energy transfer in the atmosphere is baffling anyway. Simple conduction and convection are far more important:
- To feel the temperature of a warm object (poorly child's forehead or hot water bottle), you have to actually touch it = conduction.
- Put your hand one inch to the side of a hot object (hot radiator, candle flame etc) = radiation; then put it one inch above that object = convection, which feels a lot warmer than one inch to the side.
- You have to get really hot, like a bonfire, for radiation to outweigh conduction, and even then, it's a lot hotter directly above it (convection + radiation) than to one side (radiation).
- The atmosphere is on the whole a lot cooler than a poorly child's forehead, so we can safely assume that the majority of thermal energy transfers are by conduction and convection.

6. CO2 has a 'fingerprint' which can be observed from space. Or not, as the case might be.

The Alarmists make great play of the fact that CO2 absorbs (and emits) IR at wavelength 16 microns (sometimes expressed as 667/cm or frequency a bit less than 10^13 Hz) and that if you measure terrestrial radiation with satellites, there is a noticeable gap at that wavelength. Theory 1 says that if there is more CO2, that missing bit will be larger. But if Theories 2 and 3 are correct, then the extra radiation emitted by CO2 in the stratosphere above the EEA (whichever one) ought to fill up that gap again.

As a final thought, let's imagine a counter-factual where CO2 levels are increasing (true) and the stratosphere were warming instead of cooling. Would the Alarmists shout 'slam dunk!' or would they accept it as evidence against their basic assumption that CO2 is to blame for everything? It's poor science to look for evidence to support 'your' theory or even 'a' theory. You have to remain open minded and look for evidence against as well as for, or accept that you were barking up the wrong tree.
Anyway, happy New Year's Eve to anybody who has read this far. I think I shall celebrate Indian New Year in half an hour (6.30 GMT) and then call it a night.


Lola said...

Nicely done. My view is that CO2 / MMGW is based on the same technique as in an earlier times the Medieval Catholic Church used its supposed superior interpretation of The Bible to sell indulgences and keep the proles under the the thumb and stumping up 'rents', or tithes as they were then called.
That is, it's a racket.

Bayard said...

The original and still the best....

Bayard said...

"It's poor science to look for evidence to support 'your' theory or even 'a' theory. You have to remain open minded and look for evidence against as well as for, or accept that you were barking up the wrong tree."

Er no, it's poor science to look for evidence to support a theory, full stop. The scientific method states that you should only look for evidence that disproves a theory. What "proves" a theory is the absence of disproof, not the presence of "proof". All the "proof" is, is further examples of the phenomena that the theory is explaining and, as such, are of no scientific relevance. That is why climate "scientists" aren't really scientists.

Mark Wadsworth said...

B, what about when Eddington and Einstein looked at the solar eclipse?

Do you count that as looking for evidence to support gravity bending theory or as looking for evidence to debunk it?

It's easy to show that light doesn't bend in gravity - you just do smaller scale experiments.

Mark Wadsworth said...

L, ta.

Bayard said...

Well the classic scientific method goes:

Here is a phenomenon.

This is my theory to explain that phenomenon.

Now I must test my theory: if my theory is correct, we should also observe this other phenonomenon and, if we don't observe this other phenomenon, then my theory will need to be amended.

By observing the eclipse, Einstein and Eddrington were able to test the theory of light being bent by gravity. No doubt they hoped that the test would not disprove the theory, but I hope they were good enough scientists not to think, that, if the theory passed the test, that it was in any way "proved".

Mark Wadsworth said...

B, agreed.

Problem with AGW is that they take anything to 'prove' their theory. Stratosphere cools = proved
Stratosphere warms = proved

But given the importance, we have to work on basis of "reasonably likely". Same as lead in petrol, we can never be 100.0000% sure that it causes brain damage. It might be millions of coincidences. In such a case, anything more than 90% likely is good enough reason to ban it.

Mark Wadsworth said...

... as it happens, with CO2 there is little or no correlation and the question of causation is open to doubt.

Ozone theory on the other hand, does look reasonably likely and is at least worthy of further testing.