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Utopia Talk / Politics / In which Sam continues his education
Seb
Member
Mon Nov 27 13:20:18
A quick recap: all threads in order from latest to earliest.

http://www...hread=81457&time=1511778230141

http://www.utopiaforums.com/boardthread?id=politics&thread=81418&time=1510366038823

http://www.utopiaforums.com/boardthread?id=politics&thread=81370&time=1509928219472

http://www.utopiaforums.com/boardthread?id=politics&thread=81315&time=1509928219472

http://www.utopiaforums.com/boardthread?id=politics&thread=81307&time=1509928219472

http://www.utopiaforums.com/boardthread?id=politics&thread=81256&time=1509928219472

http://www.utopiaforums.com/boardthread?id=politics&thread=81179&time=1509928219472

http://www.utopiaforums.com/boardthread?id=politics&thread=81150&time=1509928219472

http://www.utopiaforums.com/boardthread?id=politics&thread=81115&time=1509928219472

http://www.utopiaforums.com/boardthread?id=politics&thread=80996&time=1509928219472

__

Where have we got to?

Sam had conceded that actually any power spectrum change results in an entropy content change for a given radiation field with given power.

However, when he realised the dire implications of this - namely that he had been wrong all this time - he quickly realised this violated conservation of face (face being a core physical quantity) and promptly explained that if the power spectrum changed, but the radiations temperature changed, then all would be well.

When it was pointed out that temperature and power spectrum are the same thing (there only ever being a given power spectrum for a given temperature and power) and that non black body radiation can't be said to have a well defined temperature, Sam had a minor relapse and again tried to claim that you could sort of average all of this away, despite having been demonstrably shown this was not the case earlier in the thread.

Sam's journey continues...


Seb
Member
Mon Nov 27 13:22:31
Sam:

"I can define any power spectrum by its average. Plankian or non plankian."

You disproved this earlier yourself when you noted that the sum of two power fluxes of different temperatures cannot have the same entropy content if it has the average temperature.

The natural corollary of the following:

Take a spectrum that is the superposition of two planckian distributions

50w of BB radiation with T = 200k plus 50w of BB radiation with T = 300

Now take 50w of BB radiation with T = 100 plus 50W of BB radiation with T = 400

And finally 100w at T=250.

All have different entropies.

You cannot characterise by average.


obaminated
Member
Mon Nov 27 14:07:20
This is the most drawn out argument in the history of UP. Both SA and Seb should co'own the award for "someone on the internet is wrong and i will prove it to them!"
Sam Adams
Member
Mon Nov 27 14:08:04
"Sam had conceded that actually any power spectrum change results in an entropy content change for a given radiation field with given power. "

False. You left out temperature.

Sam Adams
Member
Mon Nov 27 14:09:15

"You cannot characterise by average. "

Certainly you can, although you do not get the entire picture with only average.
Sam Adams
Member
Mon Nov 27 14:11:38
Obaminated, fixing sebs mistakes is useful practice for the mind.

I would suggest you try it... but... lol.
Sam Adams
Member
Mon Nov 27 14:27:09
Try this seb.

"50w of BB radiation with T = 200k plus 50w of BB radiation with T = 300 "

Has the same entropy as 100w 240k.

The power and entropy remain constant while average radiating temp changes.

And an object can radiate the same power at different temps if its emissivity changes. Which it certainly does in global warming.
obaminated
Member
Mon Nov 27 14:53:45
Trying to mock me while continuing a 1000+ comment argument between two posters. Homie, i have better things to do. Clearly you two dont.
Seb
Member
Mon Nov 27 15:41:14
Sam:

No. In didn't leave out temperature. As has been explained to you again and again, temperature is just a characterisation of power spectrum

"Has the same entropy as 100w 240k"

So, you know, not the average.

"And an object can radiate the same power at different temps if its emissivity changes."

Ok, so ultimately what that comes down to saying is that you want to ascribe an effective temperature to the power spectrum - namely what planckian distribution would produce the same entropy as an arbitrary distribution, and I'll use that to define an effective temperature.

1. There's no guarantee that this effective temperature will produce consistent results (e.g. it will give you the wrong radiated power if you use Stefan Boltzmann)

2. This doesn't help you - you are still looking at an entropy difference because the "effective temperature" you have defined will be different before and after CO2 concentrations change. The difference in entropy change is still there.

3. Effectively, this is you admitting that the effective radiating level being defined as that given by Stefan Boltzmann is wrong.

You've successfully relabeled your problem. You've not solved it.

Whereas before you has S= 4/3 Q/T_1 before global warming, now you have S= 4/3 Q/T_2.

What you are trying to do is claim there is some way you can change the power spectrum but still end up with T_1 = T_2.

And it's obvious you can't, because for given power, each temperature BB Planck distribution has a unique entropy.
Seb
Member
Mon Nov 27 15:47:29
Sam:

"And an object can radiate the same power at different temps if its emissivity changes. Which it certainly does in global warming."

Corollary - the entropy content changes and the work done changes.

Because S= 4/3 Q/T. So if Q is constant, and emmissivity causes T to change, so must S, and consequently as S_incident is fixed, so must the amount of work being done.

You've been arguing against this point for ten threads, and even described the idea that changing the emmissivity would lead to different temperatures and thus different amounts of work being done as "magical".

I told you you'd learn the truth. Glad I've finally convinced you - having demonstrated everywhere else leads to madness, you've adopted the position I began with.
Sam Adams
Member
Tue Nov 28 15:01:52
"S= 4/3 Q/T"

You forgot to integrate over the entire spectrum. That is the entire point you are missing. You can change average t without changing q if the distribution also changes.
Pillz
Member
Tue Nov 28 16:34:10
So this has dethroned the circumcision threads from a few years ago?

Also stopped following week's ago. Who is winning?
obaminated
Member
Tue Nov 28 17:37:22
Appears Seb.
Sam Adams
Member
Tue Nov 28 17:47:40
Obaminated talking about science rofl.
Cherub Cow
Member
Tue Nov 28 20:02:49
[Pillz]: "Who is winning?"

I'm taking SA still. Seb keeps making accounting errors and making some sci-fi level "if" statements. Even so, I would need 10 more threads to be sure. ;)
murder
Member
Wed Nov 29 01:07:07

How did this argument begin? :o)
Seb
Member
Wed Nov 29 01:36:46
Sam:

No, your definition of the effective temperature is let's find the black body curve that has the same entropy content, and characterise the spectrum by an effective temperature.

In doing that you've already calculated the entropy in order to define this effective temperature.

What you are failing to understand is that the power spectrum collectively defines the entropy content. Temperature is merely a way to characterise the shape of the spectrum. It's not a free parameter that to can use to offset the a non BB spectrums entropy content.
Seb
Member
Wed Nov 29 02:52:37
Cherub:

Nothing sci-fi about thought experiments, and "if" is the only way you can address the incorrect result of one of Sam's proposals. E.g. "if x were true then y would follow, which is inconsistent with z"


The only accounting error I can see so far is Sam's, where he thought you could add fractions by summing the denominator
Seb
Member
Wed Nov 29 02:53:24
Murder:

Like most conversations I have with Sam - him being obnoxious and me being bored.
jergul
large member
Wed Nov 29 03:34:02
Seb
How bored? Temperature characterises parts of a power spectrum. It is not an independent variable.

This is obvious to anyone who understands what a power spectrum is.

I would like to re-engage on sammy conceding that the total mass of condensed water in the atmosphere is indeed increasing.

Phase changes and temperature changes in water answers where energy is going that does not change temperature in the atmosphere(and the amount is not trivial. 270 km2 net loss of Greenland ice per year sinks a lot of energy. To name one example).
Sam Adams
Member
Wed Nov 29 09:14:03
Ok seb, if we define effective radiating temp as the blackbody equivelent of the big entropy integral, then there is no change in entropy/effective temperature.

If we use actual temperature instead, then minor temp and or entropy changes occure... in this case temp.

Regardless of how we approximate it(because that integral is messy), the final result is the same... no magical extra work done. The planet is intercepting the same slice of sunlight(neglecting minor albedo changes), and thus once it settles into its new equilibrium, is clearly doing the same work as before.
jergul
large member
Wed Nov 29 09:33:05
Sammy
What is the temperature change for

1 kg water (s) -> 1 kg water (l) @ 0C?
1 kg water (l) -> 1 kg water (g) @ 15C?

Seb
Member
Wed Nov 29 11:55:54
Sam:

You are the one that suggested you could define an effective temperature for the radiation field by calculating back from the entropy.

Remember, you argued that while two heat flows of 50w each and temperatures of 200k and 300k respectively didn't have the same entropy content of 100w at 250k, you could say

(50/300 + 50/200) = 100/T_eff

So that T_eff = 240.

Note this isn't the same thing as the effective radiating temperature which is 255k and back calculated using Steffen Boltzman which assumes a B&B spectrum and gives the temperature the earth would be if it were a black body and radiating the total power the earth is radiating.

What this shows is the flaw in both attempts to define an effective temperature.

Anyway, the point is that the only way to calculate the effective temperature you described above is to first calculate the entropy of the power spectrum, then define the temperature a black body radiation field would have if it had the same power.

Which is fine, but pointless as it would still show an increased entropy change.

What you seem to want to do is somehow come up with a change in temperature that offsets any change in entropy due to the power spectrum. This cannot be done.

Temperature is merely a parameter that defines a particular plank curved frequency distribution. If you don't have a plank curve, then you can't use temperature and you have to use the full power spectrum to calculate the entropy.

Your attempts to approximate essentially ignore the entire region of the power spectrum where the physics of the greenhouse effect work.

I'm also surprised you are now once again claiming that changed entropy due to changed emmisivity is magical, when only yesterday you said:


"And an object can radiate the same power at different temps if its emissivity changes. Which it certainly does in global warming."

Which necessarily means the entropy content must change, which means more work potential.

You seem to be contradicting yourself again.
Seb
Member
Wed Nov 29 12:03:06
Sam:

One thing that may be confusing you. Just because the same power is being emitted does not mean that no extra work is being done.

The same power is emitted as being absorbed.

That power is doing work on the atmosphere driving weather. I could extract that work (bajillions of wind turbines) but unless i was storing the energy in a sink somewhere, it ends up as heat that is radiated.

The simple fact that Q_in = Q_out doesn't tell us that no work is being done.

What tells us if work is being done is the difference in the entropy content of the incident and radiated radiation.

And what we see is that there is a change in entropy content, and this is perfectly consistent and in fact a thermodynamic requirement for more work to be being done.
Sam Adams
Member
Wed Nov 29 12:50:32
"You are the one that suggested you could define an effective temperature for the radiation field by calculating back from the entropy."

An approximation which i concede is not the full picture, but accurate enough in the context of not noticeably strengthening hurricanes.



"The simple fact that Q_in = Q_out doesn't tell us that no work is being done. "

In combination with no change to Q-in it certainly shows no change to the work being done, once temperature is no longer changing.

If there was different amounts of work being done by the earths atmosphere, while Q-in was unchanged, then the atmospheres temperature would continue to change. That is unquestioned thermo law.
obaminated
Member
Wed Nov 29 13:52:18
Ah, im not talking science at all, just looks like seb wants to keep this going and is confident.
Sam Adams
Member
Wed Nov 29 13:59:00
Pickett was confident too.
jergul
large member
Wed Nov 29 14:10:39
Obam
He is actually trying to tutor Sammy.

Sammy
Phase transitions give an increase in entropy at constant temperatures.

Your understanding of thermo law is incorrect.
Sam Adams
Member
Wed Nov 29 14:19:25
Jergul, that is utterly and entirely irrelevent.
jergul
large member
Wed Nov 29 14:29:55
Your not understanding thermo law is entirely relevant.

Seb: "The simple fact that Q_in = Q_out doesn't tell us that no work is being done. "

Sammy: "In combination with no change to Q-in it certainly shows no change to the work being done, once temperature is no longer changing."

Utterly false!

Seb
Member
Thu Nov 30 02:33:00
Sam:

Your initial argument was that this was fundamentally a breach of thermodynamics.

You called it "magical".

Now you are saying it's correct.

Which is it?

You say that your approximation is "Good enough", but you have presented no quantifiable evidence or argument to support this claim.

So let's start with that then.

Roughly how much power in a storm system on average?

(I can pick some numbers, but suggest you should choose ones you are comfortable with).
Seb
Member
Thu Nov 30 02:53:39
Sam:

"In combination with no change to Q-in it certainly shows no change to the work being done, once temperature is no longer changing."

Really?

I don't think so.

Remember we are dealing with flows.

Before CO2 doubles, you have Q_in as black body radiation at 6000k, and Q_out=Q_in as non BB radiation with some other temp.

So there's clearly higher entropy radiation leaving earth showing trivially that work is continuously done on the earth, largely in the form of driving weather. But that work ends up as heat and is radiated. You can't deduce that work by looking at Q_in and Q_out, only by comparing their power spectra and entropy changes.

Then we double co2 and emissivity changes. The entropy of outbound radiation increases. The outflow of radiation drops. Huge ammounts of energy flow into sinks - namely melting ice, raising surface temp etc.

Raising surface temperature leads to greater humidity, as eventually convection and radiative transfer are sufficient that the earth comes back into power balance.

However, the power spectrum emitted, due to emmisivity changes, is higher entropy the it was before. If you want to use temperature terms, the radiation effective temperature (the temperature it would have if it were black body rad with the same Q and S) is lower than before. The incoming radiation has the same S as before.

Trivially we can see that the work done by radiation is higher than before.

That work ends up being radiated as heat. But what a first year thermo lecturer might describe as "lower grade" heat than previously.

Incidentally, this is why global warming paradoxically causes the top of the atmosphere to cool - it's purely heated by radiative transfer.
Seb
Member
Thu Nov 30 02:54:24
But hey, let's move on to quantification if your objection is now only one of scale.
Sam Adams
Member
Thu Nov 30 14:28:03
"However, the power spectrum emitted, due to emmisivity changes, is higher entropy the it was before. "

No. If that was the case, the temperature would keep rising, and never settle into equilibrium. You cant do extra work and not continue to raise temperatures. You need to combine your knowledge of entropy with basic power balance, or you will keep violating something.

"only by comparing their power spectra and entropy changes. "

Their power spectra and enropy are the result of the atmospheres final state. Not the other way around.

Any atmosphere will settle - fairly rapidly too - into a state such that work done on the planet by its star equals work done by the planet on deep space.
Seb
Member
Thu Nov 30 14:45:36
Sam:

Why do you think temperature would keep rising?

The fact work is done on a continual basis in order to drive hurricanes now doesn't seem to cause temperatures to rise without limit.

The total energy in the earths climate will increase during the transient response, and then level out. It will be higher than before: represented in higher humidity, wind speed etc. Etc.

To sustain this requires more work done on a continual basis.

Or to put it another way, if instead of adding co2, we instead removed all GHGs from the atmosphere, what do you think would happen?



Sam Adams
Member
Thu Nov 30 15:00:08
"The fact work is done on a continual basis in order to drive hurricanes now doesn't seem to cause temperatures to rise without limit."

Because the work done now matches the ouflow. If you want to do more work than the outflow, temps rise.

"wind speed"

No, at least not due to higher energy states. Wind is purely the result of energy transfer.

"To sustain this requires more work done on a continual basis"

Absolutely and completely wrong. To sustain that requires inflows to equal outflows.


"we instead removed all GHGs from the atmosphere, what do you think would happen? "

The planet would settle on a new lower temperature such that inflows equal ouflows. Neglecting albedo changes this would be the same entropy deltas as current. Of course the cooling direction is fucking deadly... albedo changes would be massive.
jergul
large member
Thu Nov 30 15:10:57
Sammy
"Any atmosphere will settle - fairly rapidly too - into a state such that work done on the planet by its star equals work done by the planet on deep space."

Utterly false!

It will take 500 years for the oceans to absorb the temperature increase themodynamically (shown in earlier threads)

However, deep water-surface circulation takes 1000 years to fully cycle under current ocean conditions.

In sum: The atmosphere will begin to cool down and continue to cool down for 1000 years after an in-out energy balance is reached.

"The planet would settle on a new lower temperature such that inflows equal ouflows. Neglecting albedo changes this would be the same entropy deltas as current. Of course the cooling direction is fucking deadly... albedo changes would be massive."

You can see that happen in one direction, but yet cannot see it happening in the other. Funny, that.
Sam Adams
Member
Thu Nov 30 15:12:35
To know a planets equilibrium entropy deltas you need to know its: orbital radius, star's solar output, and albedo (in the solar spectrum). That. Is. All.
Sam Adams
Member
Thu Nov 30 15:14:55
"but yet cannot see it happening in the other."

Because we have nearly reached the warm side end of planetary ice. Not much solar energy falls on ice... not much room left to change that one.
jergul
large member
Thu Nov 30 15:39:11
Sammy
I am actually not sure how much albedo effect there is from current snow-ice conditions. We can let your claim stand on that albedo effect.

Do you understand the warming effect of lost ice coverage (Greenland alone is losing 400 km^3 ice a year)? Net ice loss is a significant heat sink.
Seb
Member
Thu Nov 30 15:45:52
Sam:

So, on this cooler earth, negleting albedo changes (we paint the snow a suitable colour), what is humidity like?
Sam Adams
Member
Thu Nov 30 15:51:49
Oh, so like 20 minutes of sunlight?

Ya, real big.
Sam Adams
Member
Thu Nov 30 15:54:32
"what is humidity like?"

100% relative humidity at a dewpoint of some -20C. The atmosphere is stagnant and sits there doing nothing. The world is boring and dead.
Seb
Member
Thu Nov 30 16:15:46
Sam:

Let me rephrase, is the partial pressure of water in the atmosphere greater or less than before?
Sam Adams
Member
Thu Nov 30 16:27:45
Much less. That is basically what dewpoint is. Lol.
Seb
Member
Thu Nov 30 16:32:46
Does that not imply that evaporation is much less?
Sam Adams
Member
Thu Nov 30 17:11:11
Of course evaporation is much less. There would be no need to transfer energy to the atmosphere if the atmosphere could not transfer energy to space.
Sam Adams
Member
Thu Nov 30 17:16:33
And yes, i am quite aware this indicates increasing transfer of net energy with weather and less transfer of net energy with IR as IR emissivity increases. As previously mentioned, i calculate something like a 2% increase in weather strength per increased surface degree K in our current temperature range.
jergul
large member
Thu Nov 30 21:24:24
"As previously mentioned"

Where?

You have been coming across as extremely clear on weather strength not increasing.

Now your position seems to be that yes weather strength increases as atmospheric temperature increases, but that does not effect hurricane formation frequencies, duration, or strength.

Which seems odd, given that hurricanes are simply outlier strength weather.

I think we are approaching "done" here. I don't see how you can backtrack from this.

Seb
Member
Fri Dec 01 01:52:38
Sam:

So less evaporation, less hurricanes - as you say, a stagnant and dead place.

So is it fair to say that pretty much all the surface energy is radiated directly as heat without doing work?
Seb
Member
Fri Dec 01 01:58:44
Oh, jergul skipped to the end.

Yes, it seems to me that you started this whole thing arguing that increased weather strength was impossible because that was work, and thermodynamically more work would be done on the system would be "magical" as it violates thermo, citing the fixed temperature and therefore fixed entropy of outbound radiation.

Then you eventually accepted that actually the outbound radiation entropy does increase "slightly" and the temperature was an "approximation", but the amount of work done was the same.

Then when pointed out that the changed entropy did mean more work was done, you redefined work to mean energy flowing into sinks.

And now you claim it's perfectly possible to drive greater evaporation, windspeed and yes, storm systems by adding GHG to an atmosphere.

Presumably, you will tell us, without doing any more work outside of the transition period.

There's nothing wrong with changing your mind as your thinking evolves, but it's generally good form to admit that you are doing it.

Otherwise you look quite mad.
Sam Adams
Member
Fri Dec 01 10:26:09
Pretty much everything you just said is wrong seb.

"You have been coming across as extremely clear on weather strength not increasing."

No. I have always used the words significantly or noticeably. Very minor changes changes are possible and in some cases likely. But things that small dont matter.
Seb
Member
Fri Dec 01 10:39:40
Sam:

It's a completely reasonable summary of your argument. I can assemble the direct quotes if you want.

You use the term "violation of thermodynamics". This is very, very different in meaning from "entirely consistent with thermodynamics, but too small to matter".

This is particularly puzzling as adding CO2 is enough to turn the atmosphere from being "stagnant and dead" and very dry, to one that has lots of hurricanes and humidity; but somehow doubling that CO2 will have no effect at all.

I think we can all agree that thermodynamics doesn't actually prohibit this - don't we?


So lets work out if its too small to matter.

How much energy in your average storm system Sam?
Sam Adams
Member
Fri Dec 01 11:34:31
"You use the term "violation of thermodynamics". This is very, very different in meaning from "entirely consistent with thermodynamics, but too small to matter". "

These refer to 2 entirely seperate physical processes. You are confusing different segments of our discussion.

"as adding CO2 is enough to turn the atmosphere from being "stagnant and dead" and very dry, to one that has lots of hurricanes and humidity;"

CO2 is not the only greenhouse gas. You are adding everything in the atmosphere to go from hypthetical 0 emissivity atmosphere to where we are now.


"How much energy in your average storm system Sam?"

Massive shitloads. Something like 50% of the surfaces outbound energy leaves the surface in the form of weather. 80w/m2 or so. By comparison, your 1 watt of global warming aint shit.
Seb
Member
Fri Dec 01 17:15:41
Sam:

You were very very clear that simply changing the emissivity couldn't change climate because that meant it would do more work, which was a violation of thermodynamics.


Now, as I understand it, you say changing emissivity can do work (but not much, so you assert without quantitative analysis), and climate can change without additional work when you ad ghg.

Note a non ghg atmosphere clearly doesn't have zero emissivity, I'm going to chalk that up to a brain fart.

So, you managed to dodge the question.

Total power dissipated by an average storm system?
jergul
large member
Fri Dec 01 17:22:12
Sammy
1K increases latent heat capacity of water vapour in air by 10%. Your 80w/m2 of "weather" increases by 10% for every 1K that aint worth shit of global atmospheric warming.

Ocean energy is increasing by more than 60w/m2 net as it turns out. Which is close to the "Massive shitloads" 80w/m2 you are citing.

Energy in the oceans being the driving force behind hurricanes.

So good work. You are no longer off by 4 orders of magnitude. Now you are only off by 1 order.



jergul
large member
Fri Dec 01 17:28:04
Seb
It is like watching someone draw nails over a chalkboard.

The energy of any storm = the amount of energy released by condensating water in that storm (gross values give the "weather").

Why Sammy is refusing to answer this question directly is beyond me (his 80w/m2 is latent heat in water vapour)
Seb
Member
Fri Dec 01 17:56:39
Hey, I just want a number for power dissipated by average storm. Then an average lifetime, then number of storms per year.

Sam Adams
Member
Fri Dec 01 18:18:34
"
You were very very clear that simply changing the emissivity couldn't change climate because that meant it would do more work, which was a violation of thermodynamics. "

Wrong.

"Note a non ghg atmosphere clearly doesn't have zero emissivity"

Wrong. This shows enough thought to be worth a response though. Think about it. If it has IR emissivity and is above the surface, its a greenhouse contributor. Or i should say so long as it has IR emissivity greater than 0 AND has solar transmissivity higher than 1-IRemiss.

"you say changing emissivity can do work "

On individial elements. Not on the system a whole. Oh and specify IR.

" you assert without quantitative analysis"

Wrong


"Total power dissipated by an average storm system?"

Irrelevent. Each individual storm does not occur in isolation. But to answer your question... somewhere around 2000w/m2 for a large cane, averaged over its CDO Probably peaking around 25,000w/m2 for high end eyewalls. Above 50,000 for the great plains supercells. Fuck ya now thats some power.

"1K increases latent heat capacity of water vapour in air by 10%."

Wrong.

"Your 80w/m2 of "weather" increases by 10% for every 1K "

Wrong.

"Ocean energy is increasing by more than 60w/m2"

Wrong. Lol, not only wrong but idioticly wrong.


"The energy of any storm = the amount of energy released by condensating water in that storm"

Wrong, but close at least.
Seb
Member
Fri Dec 01 18:24:01
Sam:

You haven't answered the question. I'm not asking for a large storm or power per unit area.

Answer the question.
Sam Adams
Member
Fri Dec 01 18:29:00
The maximum concievable storms power is probably around 300,000 W/m2 assuming 6000 j/kg CAPE and updraft speed of 100 m/s at a density of 0.5 kg/m3.

Thats beyond any hurricane however.
Sam Adams
Member
Fri Dec 01 18:34:12
Seb you cant multiply surface area times power per unit area by yourself?
Seb
Member
Fri Dec 01 18:35:32
I can. But I want your figure.

I didn't ask for the maximum conceivable.

Do you have comprehension issues?
Seb
Member
Fri Dec 01 18:38:59
This isn't a trick question Sam. It's not a hard question. Just, on average, power dissipated by an average storm. There's various data sets on that. There's may ways to soon a cat, so pick a value *you* feel comfortable with.

If I pick a number you'll quibble with it
Sam Adams
Member
Fri Dec 01 18:45:05
Ok i was ranting with that last one because plains supercells are awesome.

Anyway, back on subject, i see hurricanes transferring about half a percent of the planets weather energy. Before you get all excited about that number being comparible in scale to global warmings influence, and thus hoping to say hurricanes could potentially more than double, i am going answer "storms do not occur in isolation" and then laugh at you.
jergul
large member
Fri Dec 01 19:49:27
Sammy
I think you misunderstand this thread. You are the one being schooled.

"1K increases latent heat capacity of water vapour in air by 10%"

True.

It does this by increasing the mass of water in saturated air. It increases by 10% for every degree in the 20-30 range.

"Ocean energy is increasing by more than 60w/m2"

True.

This is pure subtractive math. Energy into water minus energy out of water in joules per second per m2.

"The energy of any storm = the amount of energy released by condensating water in that storm"

True enough as an approximation for ease of discussion.

Also, Seb is asking a very specific question that is relatively easy to answer. Answer it.

Seb
Member
Sat Dec 02 05:37:34
Sam:

So, you do now agree that at half a percent, hurricanes aren't even a rounding error?

Sure, they don't happen in isolation, but the radiative forcing that takes us from "cold, dead and dry" to "lots of hurricanes, humid" is comparable to that of doubling.

And under the "no GHG, cold, dead and dry" scenario that radiative forcing didn't simply result in energy being evenly distributed over existing climatic processes did it?

Generally it's quite normal that such forcing scenarios leads to driving the higher order turbulent heat transport processes.

You can perfectly reasonably look at hurricanes as a heat transport mechanism and water vapour as the working fluid.

In analogous systems one would not be at all surprised if a forcing primarily drove more of those events.
Sam Adams
Member
Sat Dec 02 17:48:17
Jergul, nothing you say is correct.

Seb, of course you can look at hurricanes as heat transfer. Every single atmospheric motion is causing, and the result of, heat transfer. It results in a system that is quite well balanced.

"the radiative forcing that takes us from "cold, dead and dry" to "lots of hurricanes, humid" is comparable to that of doubling. "

If you mean the doubling of co2, you would be completely and utterly wrong. CO2 doubling actually results in an IR emissitivity change of perhaps 10%, maybe 15%.

"scenario that radiative forcing didn't simply result in energy being evenly distributed over existing climatic processes did it? "

Actually it did. There are 2 channels for heat to flow upwards. Weather, and IR. Get rid of weather, and everything moves to IR.
jergul
large member
Sat Dec 02 20:40:28
Sammy
Actually, we have reached the point where nothing you say is correct.
jergul
large member
Sat Dec 02 20:41:48
Go back to school.
Seb
Member
Sun Dec 03 07:05:35
Sam:

Actually the *only* way heat can leave the earth is IR.
Sam Adams
Member
Sun Dec 03 11:02:34
Did i say leave the earth? No. I said upward.
Seb
Member
Sun Dec 03 13:57:24
There is a point where radiative transfer is the only way upward.

Even with no GHG, convection will dominate in the lower atmosphere.
Sam Adams
Member
Sun Dec 03 18:52:10
"There is a point where radiative transfer is the only way upward."

True. But there are 2 paths upward below that point.

"Even with no GHG, convection will dominate in the lower atmosphere."

False. An atmosphere with no GHG would have no convection at all. Think about it. An atmosphere with no IR emmissivity never cools at its top, and would never drive convection.
Seb
Member
Sun Dec 03 21:29:33
Sam:

"An atmosphere with no IR emmissivity never cools at its top, and would never drive convection."


So in your mind, GHG provide IR emmissivity? No GHG mean that the atmosphere doesn't emit IR?

Seb
Member
Sun Dec 03 21:38:26
This is also frankly bizarre line of argument from a guy that stated this argument with the position that gradients can't change because the top of atmosphere temp was fixed by power balance, now arguing it's temp is entirely determined by chemistry.
Sam Adams
Member
Mon Dec 04 09:14:25
"No GHG mean that the atmosphere doesn't emit IR? "

Correct. All outgoing IR would be transmitted through the atmosphere directly to space from the surface. And the effective radiating temp(the surface) would be the same as before... along with the entire atmosphere for that matter.

Now obviously no real atmosphere can do that, at least not perfectly, but it is an interesting thought excersize for high end undergrads.
Seb
Member
Mon Dec 04 17:46:34
So, in your mind a pure nitrogen gas ball is unable to cool itself?
Seb
Member
Mon Dec 04 17:51:01
This I find enormously interesting. Sam thinks that if the earths atmosphere was 100% nitrogen, it would essentially freeze out.

I think what would happen is that convection and conduction by the nitrogen would doninate heat transport at the surface, far more power would move into the atmosphere that way from the surface than from IR.
Sam Adams
Member
Mon Dec 04 18:14:28
A theoretical atmosphere with 0 IR emissivity is isothermal(except for a tiny boundary layer), and has the same temperature as its surface, having matched the average surface temperature slowly over time with conduction. A very thin boundary layer would heat and cool by conduction as the surface heats and cools with time of day and season. However the atmosphere as a whole loses no energy to space and thus recieves no net surface energy. The surface meanwhile would behave as if it were the surface of an airless world, heating and cooling more rapidly.
Seb
Member
Mon Dec 04 23:53:35
Sam:

So why do you think that simply removing the principle green house gases will create a magical substance with these optical properties?

Perhaps you've not read the question?
Sam Adams
Member
Tue Dec 05 08:57:13
IR emissivity equals greenhouse gas, with the added, usually minor, step of not being a solar reflector either.

This is your hypothetical scenario.
Seb
Member
Tue Dec 05 11:48:20
Sam:

Thre's a list of designated GHGs where the effect is significant.

I think it is interesting that your defintion makes any real gas a greenhouse gas, as though the IR aborbtion bands are identical.

Seem a rather unrealistic model.

So if the hypothetical is confusing to you, lets say "where the CO2 and IPCR designated GHG partial pressure has been replaced with N2."


Sam Adams
Member
Tue Dec 05 11:59:19
Yes seb, any real gas is going to have some IR emissivity. I can certainly concieve an atmosphere that reflects more sunlight than it blankets IR, but most atmospheres provide a warming effect.
Seb
Member
Tue Dec 05 13:00:53
Sam:

You still appear to be ignoring the question with some rather bizzare definitions.


Do you think nitrogen have the same forcing here as co2?

Sam Adams
Member
Tue Dec 05 13:09:18
No seb, different chemicals have different forcings. Your point?
Seb
Member
Tue Dec 05 13:34:21
My point is you seem to be vaguely pretending because Nitrogen - which makes up the bulk of the atmosphere, has some IR emmissivity, that it can be considered a greeghouse gas ("IR emissivitiy equals greenhouse gas") and so that a statement like "what happens if we remove the green house gasses" can only reasonably be answered by invoking a magical ultra transparent gas. This seems odd as almost all of the deviation from the earth having the temperature predited by Stefan boltzman is attributable to CO2*.

When asked to focus on nitrogen, you waive the question away by saying "any real gas is going to have some IR emissivity".

I'm not asking you to conveive of anything. I'm

The simple question was about what happens when you start with an atmosphere of nitrogen/oxygen and add a GHG. This odd redefinition of nitrogen/oxygen as being GHG simply because they have some IR absorbtion is a weird definition that only you seem to be using.

It's almost like you are trying to be obtuse to avoid answering sensibly.

*(if H2O is modelled as a feedback rather than a driver, given it's concentration is entirely determined by the concentration of other GHGs)
Sam Adams
Member
Tue Dec 05 15:22:39
Seb you said remove the greenhouse gasses. I removed all of them. You got all confused with the physical effects of that and now want to redefine a greenhouse gas as the major players.

Fine. the effects are basically the same... if you remove most of the greenhouse gases you get a mostly stagnant atmosphere where it is mostly uninvolved in the planetary radiation budget.

The planet is still cold and its atmosphere generally still inactive.
jergul
large member
Tue Dec 05 17:58:03
The physical effects of removing all greenhouse gases (defined as anything with an IR greater than 0)is vacuum. Whatever gases remained would solidify as part of the surface.

The physical effects of low temperatures being that gases turn into solids.
Seb
Member
Tue Dec 05 18:29:06
Sam:

Yes, you removed all greenhouse gases, by defining any gas as a greenhouse gas.

Which is not the accepted definition of greenhouse gasses.

And then you got all evasive.

The point is the addition of a trace amount of CO2 to this cold climate results in a big increase in convection.

So clearly the assumption being that then doubling that CO2 concentration wouldn't result in all heat transport channels increasing proportionately, which was the thrust of your earlier argument.
Sam Adams
Member
Tue Dec 05 19:06:16
Seb, Almost all gasses are in fact greenhouse gasses. Obviously some are better than others.

"So clearly the assumption being that then doubling that CO2 concentration wouldn't result in all heat transport channels increasing proportionately"

Seb, the change in weather heat flux with change in IR emissivity is highly nonlinear. The lions share of the change happens at first, mainly to control an intensely strong boundary layer. Continuing to bump CO2 has a diminishing effect on the shift from upward net IR flux to upward weather heat flux. Like i said before... 2% is the theoretical value we have produced and no observable change has been detected.
jergul
large member
Tue Dec 05 19:24:10
Sammy
10% is the theoretical value we have produced. 1 Centigrade increase in air temperature increases water saturation mass in air by 10%.

The "upward weather heat flux" being primarily a function of water vapour.
Sam Adams
Member
Wed Dec 06 09:08:56
Lol@the minds of peasants.
Seb
Member
Wed Dec 06 10:12:42
Sam:

Ok, you are using some batshit crazy definition of your own devising. That's interesting. Lets use the definition used by the IPCCR.

So, it's highly nonlinear, which definitely supports your belief that additional energy will be evenly distributed....


" Like i said before... 2% is the theoretical value we have produced"
You never showed your workings. Or even described them. Worse than jergulmaths

" and no observable change has been detected."

Which, given CO2 concentrations are rising and we are not even half way through the transient response is neither here nor there.
Sam Adams
Member
Wed Dec 06 10:33:49
"which definitely supports your belief that additional energy will be evenly distributed.... "

What are you talking about? What "additional" energy? The magic energy you have added to the system. Or the tiny amount of extra weather, which you think will affect hurricanes and only hurricanes?

"You never showed your workings"

There is no simple equation for this one. The minimum is a radiative convective column model with moisture. Which is a bit complex but not terrible. Still youll need a solid understanding of atmospheric physics and good programming ability in a compiled language. Your bullshit languages like matlab wont cut it, and the process will be painfully slow in a shell.
This is probably beyond your abilities, but you have a slight chance of pulling it off.

"given CO2 concentrations are rising and we are not even half way through the transient response is neither here nor there"

If we expect a large change in the future we would have seen some change by now.

Ergo, no large change is coming. Its that simple.
Seb
Member
Wed Dec 06 10:39:58
Sorry, should have said additional forcing.
Seb
Member
Wed Dec 06 10:40:51
" The minimum is a radiative convective column model with moisture."

Which model? Of your own devising? Post source code?
Seb
Member
Wed Dec 06 10:44:31
"This is probably beyond your abilities, but you have a slight chance of pulling it off."

Literally have a PhD in heat transport, and have written models as part of that. MATLAB... Pfsh, grow up Sam.

"If we expect a large change in the future we would have seen some change by now"

The GCMs that predict this don't predict it occurring now. So that seems something of a straw man.
Seb
Member
Wed Dec 06 10:46:04
In any case additional energy is accurate to an extent. The forcing raises temperatures, we both agree that, so there's additional internal energy in the system, even if the power flows in and out are the same.

Not magical, just physics.
Sam Adams
Member
Wed Dec 06 11:36:08
"The GCMs that predict this don't predict it occurring now"

Lol. So not only a trash model forceast, but an illogical one at that. The extrapolation of the current trend is a far more reliable forecast than these low res trash models. Even the best global weather model, the european one, with much better physics than every gcm, overhypes every hurricane. The US global model is even worse.

"even if the power flows in and out are the same"

That is what matters.

Also i cannot post that source code, as it is behind some security.
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