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ggchuck
2008-Nov-01, 09:49 PM
AGW Greenhouse effect: How does it work? Can anyone explain it in layman's terms and clarify the confusion I encounter when considering this question?

A little history to this question. When trying to verify some numbers in a discussion with an AGW denier (not on BAUT), I was told that the numbers didn't really matter because the greenhouse effect wasn't relevant. When I pressed for details, he indicated that since I didn't have the math/science background required, it was hard to explain and I might do well to read this paper (http://arxiv.org/PS_cache/arxiv/pdf/0707/0707.1161v3.pdf). Of course except for editorial/accusation/conclusion parts, the paper was beyond me. I posted it in the science section of BAUT to see if anyone here could confirm or deny the information there. I was inactive in BAUT for a while and in that time, the thread got sidetracked, split, moved, and locked without my getting any meaningful answers, so I'm trying again... this time as a specific question.

In that thread, it was pointed out that the 'greenhouse' term is not relevant even for a greenhouse. As pointed out in the paper referenced, the temperature in a greenhouse is not affected much regardless if the 'glass' does or does not absorb IR radiation.

As I understand it, the global 'greenhouse effect' occurs because there are gases that are transparent to sun radiation but absorb the IR radiation from the earth. It is the radiative heating of those gases (mostly H2O & CO2 comprising of about 1% of the total) and the subsequent conductive transfer of that heat to the rest of the atmosphere that is responsible for keeping our planet from being a frozen ball. This seems counter intuitive to me.

Assuming that 99% of the atmosphere is transparent to radiation, then the only way that 99% of the atmosphere can be heated is by conduction. I see convection as just a way to enhance the ability of gas to heat by conduction, not a vehicle to actually transfer heat. Even the greenhouse gases will be heated by conduction when in contact with a warmer surface or gas.

I guess what I don't understand is how the influence of the conduction transfer of heat of the entire planet surface is significantly altered by 1% of the gas in the atmosphere because it absorbs some of the earth radiation. It seems like the 'blanket' effect would be provided by the 99% of the gases that doesn't radiate the heat away but only loses its heat by conduction.

Hornblower
2008-Nov-01, 10:15 PM
What is AGW?

01101001
2008-Nov-01, 10:28 PM
What is AGW?

AGW: Anthropogenic Global Warming (FreeDictionary (http://acronyms.thefreedictionary.com/Anthropogenic+global+warming))

grant hutchison
2008-Nov-01, 11:00 PM
The greenhouse gases absorb and re-radiate the infrared produced by the Earth. Some of that re-radiated IR is absorbed by the Earth, and has to be re-re-radiated. And so on. Those extra IR photons bouncing between atmosphere and Earth are what raises the local temperature.

I have an analogy with tennis, which I've used before:
Here's an analogy that might be helpful, if people are still having difficulty with the "excess" energy budget at the Earth's surface. It involves a tennis game in which each tennis ball is a "package" of solar energy, fired into the game by one of those automatic ball cannons (which represents the sun).

I'm the Earth. I set up the cannon at the far end of the court to launch four balls a minute in my direction, which I then return across the net. So now I'm in "thermal equilibrium" with those four balls a minute: I'm "radiating" as many balls as I'm receiving.
Now you step up to the far side of the net. You're an atmosphere containing greenhouse gases, and you're intent on returning half my balls to me. So when I lob four over the net, you return two and let two pass.
Aargh! Now I need to deal with six balls a minute: four fresh ones from the cannon/sun, and two old ones returned by you/the atmosphere. I adjust to a new thermal equilibrium with that six-ball workload.
In that first minute, only two balls get out of our game (the two you let go past). So that's four in, two out: as a whole, our game is not in equilibrium, because it emits fewer balls than it receives from the cannon/sun, and those missing balls account for my increased workload/temperature.
But it doesn't stop there: of the two balls you returned to me, and which I've now returned to you, you must knock back one. So of the total six balls I dealt with, you intercept three and send them back; three others escape the game. (The game has just retained another ball, since the cannon/sun emitted four balls in the time it took those three to escape.)
In the next minute I have seven balls to deal with: four from the cannon/sun, three returns from you. I reestablish another, even hotter equilibrium state.
Now our whole game also achieves equilibrium, because you can't return half a ball to me, to precisely halve the seven balls I knock over the net.
We settle down into a game in which every minute I receive four fresh balls from the cannon/sun, and three returns from you/the atmosphere. You intercept three of my seven balls and return them, and let four go past: four in, four out.

From the outside, our game is in equilibrium with a "warm" four balls a minute. Inside the game, I'm sweating my way through seven balls a minute (I'm hot), and you're working on three balls a minute (you're cool).
The extra three balls that are sustaining our workload were absorbed into the game during a transient disequilibrium when the greenhouse effect kicked in. (And of course, they're not always the same three balls.)

Ken G subsequently pointed out that:
And even if you can return half a ball, the infinite sum converges to 8 instead of 7. The way the numbers actually work out, it seems that "you" the atmosphere are returning 3/4 of the balls that "Grant" the Earth is hitting over the net.The fraction the atmosphere returns is of course smaller than in my analogy, but the principle is the same.

Grant Hutchison

timb
2008-Nov-02, 12:02 AM
What G&T get right is that the atmospheric greenhouse effect isn't what mainly causes real greenhouses to be warm.

Ronald Brak
2008-Nov-02, 12:16 AM
The wikipedia article is a decent introduction:

http://en.wikipedia.org/wiki/Greenhouse_effect

Their article on global warming is also decent:

http://en.wikipedia.org/wiki/Global_warming

ggchuck
2008-Nov-02, 12:33 AM
I have an analogy with tennis, which I've used before:
I was hoping for something more definitive than a analogy as most analogies have flaws. Perhaps it gives a visual of the dynamics, but as I see it, after the first 12 hours, the cannon shuts down for 12 hours to reload. In the first minute the last eight balls are returned; the second minute, four; the third minute, two; the fourth minute, the last one. If we split the ball, the fraction becomes very small in the first hour. That allows 11 more hours to find any stray balls lying around and get rid of them as well.

I don't see where conduction plays a part in this analogy. I was hoping that someone would know the relationship of heat loss by radiation and the transference by conduction. I see the 99% of non greenhouse gases not losing its heat as rapidly as the greenhouse gases and thereby accounting for most of the cause of atmosphere keeping the earth from freezing.

grant hutchison
2008-Nov-02, 12:36 AM
I was hoping for something more definitive than a analogy as most analogies have flaws.So you want layman's terms without analogy?
I wish you luck. :)


I don't see where conduction plays a part in this analogy.
Well, the analogy just warmed up the Earth's surface and the greenhouse gases. Conduction warms the rest, as air molecules collide with each other and with the Earth's surface.
Cooling takes place at night, for sure, but not for long enough to radiate all the additional energy to space (otherwise we'd get down to three kelvin every night, with or without greenhouse).

Grant Hutchison

ggchuck
2008-Nov-02, 12:53 AM
The wikipedia article is a decent introduction:

http://en.wikipedia.org/wiki/Greenhouse_effect

Thanks for the link, but I have to admit I looked at it before and didn't find it enlightening. (Yes, I'm ignoring the link about global warming. Until I can understand what the greenhouse effect is, I'm won't be able to address global warming).

From the first link:
Greenhouse gases warm the atmosphere by efficiently absorbing thermal infrared radiation emitted by the Earths surface, by the atmosphere itself, and by clouds. As a result of its warmth, the atmosphere also radiates thermal infrared in all directions, including downward to the Earths surface. Thus, greenhouse gases trap heat within the surface-troposphere system.[2][3][4][5] This mechanism is fundamentally different from the mechanism of an actual greenhouse, which instead isolates air inside the structure so that heat is not lost by convection and conduction, as discussed below.The concept of the atmosphere absorbing the heat is not new to me, but frankly, I don't see why that "mechanism is fundamentally different from the mechanism of an actual greenhouse". Both concepts have enclosed the convection and conduction heat retention, one bounded by glass, the other by the limits of the atmosphere. The experiment mentioned in the paper I linked to has shown that mechanism is not the reason the temperature significantly rises.

ggchuck
2008-Nov-02, 01:02 AM
So you want layman's terms without analogy?
I wish you luck. :)~lol~ Ah... you begin to see my problem.



Well, the analogy just warmed up the Earth's surface and the greenhouse gases. Conduction warms the rest, as air molecules collide with each other and with the Earth's surface.
Cooling takes place at night, for sure, but not for long enough to radiate all the additional energy to space (otherwise we'd get down to three kelvin every night, with or without greenhouse).Actually that is my point. It sounds like your analogy takes place on the moon with no atmosphere, just a shield. There is no mechanism to hold the heat once the source is gone. That is why I can't get past conduction (or insulation if you will) being the mechanism that retains atmospheric warmth.

grant hutchison
2008-Nov-02, 01:12 AM
There is no mechanism to hold the heat once the source is gone.Nothing "holds the heat", apart from the heated objects themselves. An object at a given temperature radiates only a given amount of heat per second. The sheer mass of the atmosphere, the oceans and the earth prevents them losing enough heat to cool dramatically overnight.

Grant Hutchison

ggchuck
2008-Nov-02, 06:16 AM
An object at a given temperature radiates only a given amount of heat per second. The sheer mass of the atmosphere, the oceans and the earth prevents them losing enough heat to cool dramatically overnight.That is my point. 99% of the atmosphere doesn't radiate much. This seems to overwhelm the effect of the 1% greenhouse gases. On top of that, much of the re-radiation from the surface isn't caught.

Carl_Smith
2008-Nov-02, 12:39 PM
In spite of many requests, no one has yet been able come up with a sensible mainstream exposition of just how this 'enhanced greenhouse effect' works in a quantative manner that demonstrates where the claimed ~2.5C temperature rise for 2xCO2 touted by the IPCC comes from. Until such can be demonstrated, the 'enhanced greenhouse effect' is just a much hyped hypothesis not even deserving of the label 'theory'.

If I am wrong about this, please show me where I can find such an exposition.

mugaliens
2008-Nov-02, 01:13 PM
I I guess what I don't understand is how the influence of the conduction transfer of heat of the entire planet surface is significantly altered by 1% of the gas in the atmosphere because it absorbs some of the earth radiation. It seems like the 'blanket' effect would be provided by the 99% of the gases that doesn't radiate the heat away but only loses its heat by conduction.

The sun heats the planet's surface. Most of that heat is radiated in near to far IR back into space, as most of the Earth's atomosphere is transparent to IR. Some of it, however, is not, and captures that IR, which heats the greenhouse gases via radiative heating. These heated gases then heat the non-greenhouse gases via conductive heating. The heated gases themselves (molecular-sized bits of them, anyway) convect (rise), which in trun heats more gases.

grant hutchison
2008-Nov-02, 01:39 PM
That is my point. 99% of the atmosphere doesn't radiate much. ... On top of that, much of the re-radiation from the surface isn't caught.Sure. Add these components of an atmosphere to a bare planet, and its temperature won't change much. A radiative equilibrium is achieved: energy in during the day, energy out during day and night, and a mean surface temperature as a result.
Add greenhouse gases to the mix, and the radiative equilibrium still doesn't change much when observed from the outside: same amount of energy goes in during the day, same amount of energy comes out during day and night, and the equilibrium temperature of the high atmosphere remains the same.
But inside the atmosphere, my tennis match is now going on, with photons batting back and forth between the greenhouse gases and the ground. That raises the temperature of the ground and lower atmosphere, above the equilibrium that would be achieved if all the photons just radiated straight back out to space.

Grant Hutchison

Ronald Brak
2008-Nov-02, 01:46 PM
In spite of many requests, no one has yet been able come up with a sensible mainstream exposition of just how this 'enhanced greenhouse effect' works in a quantative manner that demonstrates where the claimed ~2.5C temperature rise for 2xCO2 touted by the IPCC comes from. Until such can be demonstrated, the 'enhanced greenhouse effect' is just a much hyped hypothesis not even deserving of the label 'theory'.

If I am wrong about this, please show me where I can find such an exposition.

Well I'll give you a quick one. Take a tube with a thin plastic window at each end and fill it with air. Then send a beam of infrared radiation through the plastic windows. Very little of the infrared energy will be absorbed by the air. Most of it will pass through the windows without being absorbed by the air and causing the temperature to rise. But if you do the same thing when the tube is filled with carbon dioxide, you will find that the carbon dioxide will absorb much more of the infrared radiation than the plain air did and as a result the carbon dioxide will become warmer than the air. If you were to take a tube full of air and slowly increase the amount of carbon dioxide in it, you would also slowly increase the amount of infrared energy that would be absorbed and slowly increase the temperature. That's what's happening with our atmosphere as we increase the amount of CO2.

PraedSt
2008-Nov-02, 01:50 PM
Thanks for the link ggchuck by the way. I'm a quarter of the way through it, it's been an interesting read so far. Some of it is over my head of course :)

mugaliens
2008-Nov-02, 02:34 PM
It's not enough to look at just IR. Rather, we must look at both the influx and eflux histograms across all wavelengths of radiative energy (examples only - not real):

Influx:
Band
1+
2++
3++++
4+++++
5+++

Eflux:
Band
1+++
2+++
3++++
4++++
5+

Put another way, for a barren rock orbiting the sun, after a very long time, the rock reaches a sort of homeostasis where the influx of energy from all wavelengths will equal the eflux of energy from all wavelengths. The incoming distribution of wavelengths isn't the same as the outgoing, as many wavelengths are not reflected, but are instead absorbed and transformed into a different type of energy such as thermal or chemical. For thermal, the energy is re-radiated immediately, but in a different frequency band, in this case, far to near IR. For chemical, the energy may be stored for millennia, or even, for all practical purposes, forever.

Radiation that's reflected can be purely reflected (the same frequency) or it can be both upchanneled (higher frequency) and downchanneled) lower frequency. Microwaves heating water which in turn radiates heat (IR) is an example of upchanneling. UV radiation causing certain chemicals to flouresce is an example of downchanneling.

Furthermore, a planet's atmosphere behaves in much the same way, but has an additional property - it's translucent. That is, it may be transparent to some frequencies, opaque to others, and scattering to yet a third group of frequencies.

For a planet like the Earth, this process has reached a sort of equilibrium. It's the reason why we're the temperature we are today. But if the composition of the gases changes, or the influx histogram changes (either in terms of composition or overall energy), it may upset the equlibrium.

You wrote:
As I understand it, the global 'greenhouse effect' occurs because there are gases that are transparent to sun radiation but absorb the IR radiation from the earth. It is the radiative heating of those gases (mostly H2O & CO2 comprising of about 1% of the total) and the subsequent conductive transfer of that heat to the rest of the atmosphere that is responsible for keeping our planet from being a frozen ball. This seems counter intuitive to me.

Why? Let's simplify this and say that there are no greenhouse gases, and that 100% of the influx is reflected off the planet's surface. The planet will reach equilibrium at a temperature, x.

Now, let's say that the planet's atmosphere absorbs just 10% of of the radiation passing through. That means that 90% of the radiation reaches the surface. And the atmosphere also absorbs 10% of the re-radiated energy, so that only 81% makes it all the way back out. Thus, for a 10% absorption rate, 19% of the total energy is actually absorbed.

Now - let's increase the absorption rate by a mere 1% and see what happens:

89% makes it to the surface, and 79.21% makes it back out. Thus, instead of absorbing 19%, the 1% increase results in 20.79% being absorbed.

That's a 9.42% increase in absorption!

Fortunately, our planet's environment, particularly it's temperature, is self-stabilizing, or dynamically stable. That is, in the mathematics of chaos, there's locus about which our planet's temperature tends to remain. Thus, when the mix changes which allows more heat to be retained, and the temperature rises, something changes which allows the Earth to give off more heat at a given temperature than it did before, and this dynamically stable effect prevents runaway temperatures.

There's a misnomer out there which states, "warming increases humidity which increases clouds which reduces heating." Anyone who's been to warm, humid, and very sunny Hawaii (and other humid equitorial regions) knows this is false. Rather, it's the clash of humid air with cooler air which produces the Earth-cooling clouds, as evidenced by both fronts (thunderstorms), as well as convection cooling (tropical storms).

But this uncovers another misnomer: clouds cause cooling. The truth is that while clouds do reflect much energy, the do so both ways. Thus, the main effect of clouds is as a dampener. Anyone who's seen desert temps drop from 110 in the day to 65 at night understands this, as cloudy days in the desert rarely produce daytime temps above 90, but if the clouds remain, the temps rarely drop below 70.

mugaliens
2008-Nov-02, 02:52 PM
Thanks for the link ggchuck by the way. I'm a quarter of the way through it, it's been an interesting read so far. Some of it is over my head of course :)

I hope you're taking notes - I'd be interested in comparing them when you're done (meaning, I've written enough, here, for now).

Disinfo Agent
2008-Nov-02, 03:12 PM
The summaries provided in this thread (http://www.bautforum.com/general-science/76506-another-catastrophie-due-global-warming-9.html#post1300369) seemed pretty good.

dmr81
2008-Nov-02, 03:34 PM
In spite of many requests, no one has yet been able come up with a sensible mainstream exposition of just how this 'enhanced greenhouse effect' works in a quantative manner that demonstrates where the claimed ~2.5C temperature rise for 2xCO2 touted by the IPCC comes from. Until such can be demonstrated, the 'enhanced greenhouse effect' is just a much hyped hypothesis not even deserving of the label 'theory'.

If I am wrong about this, please show me where I can find such an exposition.

Specific rebuttal of the paper referred to in the OP:
Smith 2008 (http://arxiv.org/abs/0802.4324)

Radiative forcing due to greenhouse gases:
Myhre et al 1998 (http://www.agu.org/pubs/crossref/1998/98GL01908.shtml)

Climate sensitivity:
Annan 2006 (http://www.jamstec.go.jp/frcgc/research/d5/jdannan/GRL_sensitivity.pdf)
Tung 2007 (http://www.amath.washington.edu/research/articles/Tung/journals/solar-jgr.pdf)

Simplified explanation:
http://www.realclimate.org/index.php/archives/2007/08/the-co2-problem-in-6-easy-steps/

PraedSt
2008-Nov-02, 03:39 PM
Specific rebuttal of the paper referred to in the OP:
Smith 2008 (http://arxiv.org/abs/0802.4324)

Hey, excellent. I wanted to read the other side. Thanks.

ggchuck
2008-Nov-02, 03:52 PM
Hi Mugs,
Thanks for reading my stuff.


The sun heats the planet's surface. I'm with you so far.


Most of that heat is radiated in near to far IR back into space, as most of the Earth's atomosphere is transparent to IR. Some of it, however, is not, and captures that IR, which heats the greenhouse gases via radiative heating.Still with you. I've found this figure (http://en.wikipedia.org/wiki/Image:Atmospheric_Transmission.png) illustrative in that regard.


These heated gases then heat the non-greenhouse gases via conductive heating. The heated gases themselves (molecular-sized bits of them, anyway) convect (rise), which in trun heats more gases.Still with you, but diminished a bit because those heated greenhouse gases also heat the ground by radiation.

What I don't have a feel for is the quantity of heat that the greenhouse gases pass to the other 99% of the atmosphere relative to the fact that the ground conducts heat to 100% of the gases and with the help of convection, the temperature difference is often significant thereby facilitating that transfer. It seems intuitive that heating of 99% of the gases by conduction is the primary reason that we are not on a frozen planet, not the partial radiative energy that the 1% is able to capture.

dmr81
2008-Nov-02, 03:54 PM
I posted it in the science section of BAUT to see if anyone here could confirm or deny the information there. I was inactive in BAUT for a while and in that time, the thread got sidetracked, split, moved, and locked without my getting any meaningful answers

:liar:

I posted (http://www.bautforum.com/against-mainstream/80189-greenhouse-effect-even-relevant-global-warming.html#post1316875) a link to the rebuttal paper 30 minutes after you posted the thread. Several other people pointed out the obvious flaws in your argument and you clearly saw them because you responded (http://www.bautforum.com/against-mainstream/80189-greenhouse-effect-even-relevant-global-warming.html#post1319069) afterwards.

ggchuck
2008-Nov-02, 04:02 PM
...inside the atmosphere, my tennis match is now going on, with photons batting back and forth between the greenhouse gases and the ground. That raises the temperature of the ground and lower atmosphere, above the equilibrium that would be achieved if all the photons just radiated straight back out to space.Many of the photons that hit the ground gets radiated back at wavelengths that are not be visible to the greenhouse gases. The figure I linked to in my reply to Mugs shows some of the details. As a side note, it also illustrates why CO2 is significant (by its position in the Planks curves at the top) even though water vapor is far more massive.

Your tennis game still only addresses radiation. The bouncing radiation ultimately leaves the system. Though I don't have a feel how many bounces it takes for a photon to leave the earth or how fast they bounce, it appears that they should escape relatively quickly unless the heated greenhouse gas heats a non-radiating gas by conduction.

grant hutchison
2008-Nov-02, 04:19 PM
Your tennis game still only addresses radiation. The bouncing radiation ultimately leaves the system. Though I don't have a feel how many bounces it takes for a photon to leave the earth or how fast they bounce, it appears that they should escape relatively quickly unless the heated greenhouse gas heats a non-radiating gas by conduction.Well, since photons are absorbed and re-emitted, it's impossible to say how quickly one photon leaves the system, since there's no continuity between the absorption and the re-emission.
The rate at which one photon leaves the system is irrelevant, however. What matters is the extra burden of absorption and re-emission, involving many photons, which requires a higher equilibrium temperature at the Earth's surface.

Grant Hutchison

ggchuck
2008-Nov-02, 04:23 PM
...Let's simplify this and say that there are no greenhouse gases, and that 100% of the influx is reflected off the planet's surface. The planet will reach equilibrium at a temperature, x.For earth it's approximately 31% reflected (Energy budget diagram (http://www.cgd.ucar.edu/cas/papers/bams97/fig7.gif)).


Now, let's say that the planet's atmosphere absorbs just 10% of of the radiation passing through. That means that 90% of the radiation reaches the surface. And the atmosphere also absorbs 10% of the re-radiated energy, so that only 81% makes it all the way back out. Thus, for a 10% absorption rate, 19% of the total energy is actually absorbed.[My comment was flawed and I deleted it until I have a chance to re-think it]

grant hutchison
2008-Nov-02, 04:28 PM
... but do you have an estimate of the actual numbers? It is the scale of the greenhouse effect that I'm unsure about. So far I have seen nothing that indicates that the greenhouse effect dominant enough to be responsible for keeping the earth from freezing over.It's in your linked diagram: 324 W.m-2 back-radiated by greenhouse gases. Comparable to the 342 W.m-2 coming into the system from outside, in the form of solar radiation.

Grant Hutchison

PraedSt
2008-Nov-02, 04:32 PM
I hope you're taking notes - I'd be interested in comparing them when you're done (meaning, I've written enough, here, for now).

Ha! As far as I can tell, you need several PhDs to even begin to properly understand climate; so I may be some time...

ggchuck
2008-Nov-02, 05:06 PM
:liar:

I posted (http://www.bautforum.com/against-mainstream/80189-greenhouse-effect-even-relevant-global-warming.html#post1316875) a link to the rebuttal paper 30 minutes after you posted the thread. Several other people pointed out the obvious flaws in your argument and you clearly saw them because you responded (http://www.bautforum.com/against-mainstream/80189-greenhouse-effect-even-relevant-global-warming.html#post1319069) afterwards.Before I became inactive, there were several exchanges in that thread. Several points were brought up that showed my ignorance of the subject and links to papers that were beyond my ability to digest. I still don't have the background to promote the validity of the OP paper nor I do have the background to relate the technical paper you offered in rebuttal.

I never got an answer that satisfied me that was at a level I could understand. As the AGW denier I referred to in the OP indicated, without getting a degree in math and physics, I may never understand. I was hoping that someone here who does have the necessary background could address the specific questions that still bother me in a way that I would understand.

Right now, the link you labeled "simplified" may be at the right level. It will take me a while to digest it.

grant hutchison
2008-Nov-02, 06:14 PM
It's in your linked diagram: 324 W.m-2 back-radiated by greenhouse gases. Comparable to the 342 W.m-2 coming into the system from outside, in the form of solar radiation.Oops. I notice that the diagram doesn't say how the atmosphere acquired this energy, even though the arrow originates from a region marked "greenhouse gases". So there's a contribution from gases that have been heated by convection and condensation in that 324 W.m-2.

But "comparable to the energy from insolation" is the correct ballpark. You'll find slightly different figures in different reference sources, but the relative magnitudes are about the same. From Ahrens' Meteorology Today, the heat the Earth transfers to the atmosphere is made up in the following approximate proportions: 5% by conduction/convection; 15% by evaporation/condensation; 80% by radiation/absorption. The radiative transfer is the major component, and is mediated almost entirely by greenhouse gases.
The atmosphere then reradiates all this energy: that's what contributes to the 324 W.m-2 sent back to Earth in your diagram.

Grant Hutchison

mugaliens
2008-Nov-02, 06:24 PM
The bouncing radiation ultimately leaves the system. Though I don't have a feel how many bounces it takes for a photon to leave the earth or how fast they bounce, it appears that they should escape relatively quickly unless the heated greenhouse gas heats a non-radiating gas by conduction.

Regardless, since the Earth's temperature has been relatively stable for several thousand years, and since we've all experienced how small changes in cloud cover can dramatically change the temperature, it simply follows, logically, that we're either radiating about as much as we're receiving, or the difference is made up from internal heating.

Jeff Root
2008-Nov-03, 12:42 AM
Mugs,

I almost skipped over your post #18, because it looked long and dull.
Instead it turned out to be a really quick and clear explanation of a
major atmospheric process! Thanks!

-- Jeff, in Minneapolis

Carl_Smith
2008-Nov-03, 01:08 AM
In spite of many requests, no one has yet been able come up with a sensible mainstream exposition of just how this 'enhanced greenhouse effect' works in a quantitative manner that demonstrates where the claimed ~2.5C temperature rise for 2xCO2 touted by the IPCC comes from. Until such can be demonstrated, the 'enhanced greenhouse effect' is just a much hyped hypothesis not even deserving of the label 'theory'.

If I am wrong about this, please show me where I can find such an exposition.

(Edit Note: corrected earlier spelling mistake in this version - Carl)



Specific rebuttal of the paper referred to in the OP:
Smith 2008 (http://arxiv.org/abs/0802.4324)

This does not deal with the 2xCO2 case, so does not answer my question.



Radiative forcing due to greenhouse gases:
Myhre et al 1998 (http://www.agu.org/pubs/crossref/1998/98GL01908.shtml)

Money walled, so no use whatsoever to me - however it says in the absract that it is a radiation modeling exercise, so is unlikely to be the physics based exposition of the ~2.5C for 2xCO2 claimed by the IPCC that I'm looking for - perhaps someone with access can quote the relevant part showing that it is in there if I'm wrong?



Climate sensitivity:
Annan 2006 (http://www.jamstec.go.jp/frcgc/research/d5/jdannan/GRL_sensitivity.pdf)

This is not a physics exposition, but simply imposes a somewhat tighter restraint on an existing "subjective estimate" using radiation models.



Tung 2007 (http://www.amath.washington.edu/research/articles/Tung/journals/solar-jgr.pdf)

Once again, not a physics exposition, but a modeling exercise dependent in part on the accuracy of paramaterizations of certain dynamic processses (i.e. educated guesses in place of real physics) built into GCMs - it is nevertheless an interesting read.



Simplified explanation:
http://www.realclimate.org/index.php/archives/2007/08/the-co2-problem-in-6-easy-steps/

RealClimate as a credible science source? You've got to be joking!

Where is the definitive mainstream quantified physics exposition of the ~2.5C increase in temperature for 2xCO2 touted by the IPCC?

BTW, in case anyone doubts the importance of this, the whole future of carbon trading schemes and all else arising from AGW mitigation depends on the accuracy of this single IPCC claim. If the T increase ~2.5C for 2xCO2 is more than marginally too high (and I suspect it is - see here (http://www.weatherquestions.com/Global-warming-natural-PDO.htm) and here (http://arxiv.org/ftp/arxiv/papers/0809/0809.0581.pdf)), other factors contributing to natural climate variability are probably dominant, and efforts to curb greenhouse emissions to control climate appear to be doomed to be a very expensive failure before they even begin.

Ronald Brak
2008-Nov-03, 01:40 AM
Where is the definitive mainstream quantified physics exposition of the ~2.5C increase in temperature for 2xCO2 touted by the IPCC?

Did you find the explanation I wrote for you earlier in the thread helpful?

Carl_Smith
2008-Nov-03, 02:54 AM
Did you find the explanation I wrote for you earlier in the thread helpful?

Ronald, that there is some warming due to greenhouse gasses in the atmosphere due to IR effects is not in dispute.

What is important is quantification of the amount of warming in the real atmosphere for 2xCO2 from pre-industrial times, which the IPCC claims is ~2.5C. As far as I know, the IPCC number is an educated guess constrained by the output of computer models with all their known shortcomings, and has never been adequately quantified in a physics based exposition in the literature.

If I am wrong, please show me where to find it.

Ronald Brak
2008-Nov-03, 03:56 AM
Ronald, that there is some warming due to greenhouse gasses in the atmosphere due to IR effects is not in dispute.

What is important is quantification of the amount of warming in the real atmosphere for 2xCO2 from pre-industrial times, which the IPCC claims is ~2.5C. As far as I know, the IPCC number is an educated guess constrained by the output of computer models with all their known shortcomings, and has never been adequately quantified in a physics based exposition in the literature.

If I am wrong, please show me where to find it.

Are you asking if you are wrong about the existance of a mainstream explanation that you can understand? I'm afraid that is something that only you can answer.

parejkoj
2008-Nov-03, 04:22 AM
Well, Carl Smith, if you won't accept the word of the climate scientists at realclimate.org (RC), who will you accept? Why don't you think their description of the science is reliable?

They have another good description about why what you are asking is unreasonable (http://www.realclimate.org/index.php/archives/2008/09/simple-question-simple-answer-no/), including references to some past examples of attempts to calculate it. Perhaps one of those would satisfy you?

ggchuck: the above reference also has links to some decent descriptions of your question, though I'm not sure whether they are "above" or "below" your level. Also, the RC wiki has links (http://www.realclimate.org/wiki/index.php?title=G._Gerlich_and_R._D._Tscheuschner) to a variety of replies to G&T's nonsense paper. Some are fairly technical, some not so. The link that dmr81 posted above (http://www.realclimate.org/index.php/archives/2007/08/the-co2-problem-in-6-easy-steps/) also has some good descriptions of CO2 forcing.

But I think the best answer to your question, one which provides an excellent description of what is really going on in the atmosphere, comes from this RC post in 2007 (http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument/). Please tell me if you've seen it before, or if you have any questions about it.

Carl_Smith
2008-Nov-03, 06:52 AM
Are you asking if you are wrong about the existance of a mainstream explanation that you can understand? I'm afraid that is something that only you can answer.

I am asking about an accurate mainstream step by step exposition that derives the IPCC T increase ~2.5C for 2xCO2 value from basic physics principles, not a lot of speculative hand waving based on assumed feedbacks and computer model output.

It appears to not exist, and until it does, AGW remains just another speculative hypothesis that should not even be dignified with the label theory.

Carl_Smith
2008-Nov-03, 08:59 AM
Well, Carl Smith, if you won't accept the word of the climate scientists at realclimate.org (RC), who will you accept? Why don't you think their description of the science is reliable?

Without a detailed exposition it cannot be claimed to be reliable, as it is just pure speculation.


They have another good description about why what you are asking is unreasonable (http://www.realclimate.org/index.php/archives/2008/09/simple-question-simple-answer-no/), including references to some past examples of attempts to calculate it. Perhaps one of those would satisfy you?


I am looking for a mainstream peer-reviewed step by step exposition quantifying the IPCC claims of ~2.5C warming for 2xCO2 from pre-industrial times derived from basic physics principles, not any of several half-baked blog posts posted on an AGW advocacy website loaded with flowery hand-waving explanations of how they think it works and why they think what I ask is unreasonable.

It is not unreasonable to want a sound exposition of this matter when trillions of dollars of taxpayers funds are at stake, something that climate scientists better start waking up to quick smart.

Garbage like "Trust us, we are climate scientists, we believe we know how it works, but we are unable to quantify it to demonstrate that our maths is correct" is simply not good enough.

Ronald Brak
2008-Nov-03, 09:10 AM
I am asking about an accurate mainstream step by step exposition that derives the IPCC T increase ~2.5C for 2xCO2 value from basic physics principles, not a lot of speculative hand waving based on assumed feedbacks and computer model output.

Well then, the wikipedia articles on the Greenhouse effect:

http://en.wikipedia.org/wiki/Greenhouse_effect

And Global Warming:

http://en.wikipedia.org/wiki/Global_warming

Would probably be a good place to start. Check them out and let us know if you have any questions. If I can't help you out other people on this forum certainly can.

dmr81
2008-Nov-03, 03:49 PM
This is not a physics exposition
You didn't ask for a physics exposition. If you had I would have told you -- as others have told you since -- that it is not that simple (http://www.realclimate.org/index.php/archives/2008/09/simple-question-simple-answer-no/). The papers to which I linked show how the response to a doubling of CO2 is derived. They are accepted by the vast majority of climate scientists. If you wish to dispute them then you have the burden of proof.


RealClimate as a credible science source? You've got to be joking!
If you have anything to dispute that article please provide it. Simply trying to poison the well will not suffice. RealClimate is run by qualified, working climate scientists. If you are claiming to have sufficient expertise to simply dismiss them, provide evidence of it.


If the T increase ~2.5C for 2xCO2 is more than marginally too high (and I suspect it is - see here (http://www.weatherquestions.com/Global-warming-natural-PDO.htm)
That is not a peer-reviewed paper. It is a self-published article on a creationist's website. It argues that the long term warming trend is caused by the cyclic PDO, which is nonsense (http://www.skepticalscience.com/Pacific-Decadal-Oscillation.htm).


and here (http://arxiv.org/ftp/arxiv/papers/0809/0809.0581.pdf))
Again, that is not peer-reviewed science. It was published in a social science journal (http://www.sourcewatch.org/index.php?title=Energy_and_Environment) that is well known for its politically motivated attacks on climate science, doubtless because it could not pass peer-review in a reputable science journal...

A plot of ln (CO2) is found to be nearly linear in time over the interval 1979-2004. Thus T from CO2 forcing should be nearly linear in time also.
Straw man. No climate scientists claim that CO2 is the only factor.


The atmospheric CO2 is well mixed and shows a variation with latitude which is less than 4% from pole to pole [Earth System Research Laboratory. 2008]. Thus one would expect that the latitude variation of T from CO2 forcing to be also small.
In fact it is well known that warming is expected to be greater in the arctic. See for example Holland and Bitz 2003 (http://psc.apl.washington.edu/pscweb2002/pubs/Bitzpolaramp.pdf).

You've got a lot of gall dismissing mainstream science with the wave of a hand and then asking us to take hogwash like that seriously. If you have any proper peer-reviewed science to support your claim, provide it. Otherwise withdraw your claim.

mugaliens
2008-Nov-03, 05:15 PM
Mugs,

I almost skipped over your post #18, because it looked long and dull.
Instead it turned out to be a really quick and clear explanation of a
major atmospheric process! Thanks!

-- Jeff, in Minneapolis

Thanks! I think I'm starting to get the hang of this science thing. There's a lot of theories and stuff...

Carl_Smith
2008-Nov-04, 03:42 PM
You didn't ask for a physics exposition.

An oversight on my part that was corrected as we proceeded was to omit the word "physics". I also intially spelled "quantitative" wrongly as "quantative".

For the record, my thinking is not as clear as it could be because on Wed, Thur, and Fri last week I was treated with powerful chemotheraputic drugs that are still coursing around my system for a particularly nasty form of terminal cancer, so please forgive my oversights, for which I apologise.

Perhaps I should have waited a bit longer for my head to clear more from the chemo before diving in here, but what is done is done - and after many months of focussed concentration on my own issues I must admit I am enjoying the diversion of being able to do something not directly connected with my own fight for life for a bit. :)

I promise I will not be indulging too much more of this, as my fight for life really is much more important to me than debating with people about AGW.


If you had I would have told you -- as others have told you since -- that it is not that simple (http://www.realclimate.org/index.php/archives/2008/09/simple-question-simple-answer-no/).

In my experience, when someone tries to tell me physical processes are too complicated to explain with a clear quantitative physics based exposition it often means that in reality they have no idea of what theyre talking about, and having them then imply to me that I simply have to trust that they know what they are doing even though they cannot provide the maths to demonstrate their claims inspires no confidence in me whatsoever.

Even if it takes hundreds of pages of sound physics exposition to do so then so be it - there are trillions of dollars in taxpayer funds at stake here - don't you think it is high time some climate scientists pulled their fingers out and got on with the job at hand instead of just complaining because they think it is too hard?


The papers to which I linked show how the response to a doubling of CO2 is derived.

They contain no quantitative exposition based on physics principles that I can see.

Lets look at the papers in turn:


Specific rebuttal of the paper referred to in the OP:
Smith 2008 (http://arxiv.org/abs/0802.4324)

An unpublished rant by AGW advocate Arthur Smith archived as an attempt to debunk an alternative viewpoint - an interesting read, but not a quantitative mainstream peer reviewed exposition based on physics principles that I'm looking for.



Radiative forcing due to greenhouse gases:
Myhre et al 1998 (http://www.agu.org/pubs/crossref/1998/98GL01908.shtml)


No use to me at all because it is money walled - so far nobody has posted anything that indicates it contains an answer to what I ask, however we do have the abstract:


Abstract
We have performed new calculations of the radiative forcing due to changes in the concentrations of the most important well mixed greenhouse gases (WMGG) since pre-industrial time. Three radiative transfer models are used. The radiative forcing due to CO2, including shortwave absorption, is 15% lower than the previous IPCC estimate. The radiative forcing due to all the WMGG is calculated to 2.25 Wm−2, which we estimate to be accurate to within about 5%. The importance of the CFCs is increased by about 20% relative to the total effect of all WMGG compared to previous estimates. We present updates to simple forcing-concentration relationships previously used by IPCC.
Received 9 December 1997; accepted 8 April 1998.

So it is a radiation modeling exercise using 3 different radiation models.

Of course, the real atmosphere has evaporation, convection, condensation, and precipitation all happening in varying amounts over time over varying areas, so where do all these important dynamic processes that all have a bearing on the heat content of the atmosphere therefore influencing the IR budget fit into the radiation models?

Anyway, it appears to be no help whatsoever in providing a quantitative physics based exposition of the ~2.5C warming claimed by the IPCC for 2xCO2.



Climate sensitivity:
Annan 2006 (http://www.jamstec.go.jp/frcgc/research/d5/jdannan/GRL_sensitivity.pdf)


This one is a draft by climate modeler James Annan et al. - checking James' website we find a version of it has been peer-reviewed and published by the journal GRL.

Anyway, having read it before I already know it does not contain a quantitative exposition based on physics principles, but lets dig into it a bit for some fun - here is the abstract:


Climate sensitivity has been subjectively estimated to be likely to lie in the range of 1.5-4.5 C, and this uncertainty contributes a substantial part of the total uncertainty in climate change projections over the coming century. Objective observationally-based estimates have so far failed to improve on this upper bound, with many estimates even suggesting a significant probability of climate sensitivity exceeding 6 C. In this paper, we show how it is possible to greatly reduce this uncertainty by using Bayes Theorem to combine several independent lines of evidence. Based on some conservative assumptions regarding the value of independent estimates, we conclude that climate sensitivity is very unlikely (< 5% probability) to exceed 4.5 C. We cannot assign a significant probability to climate sensitivity exceeding 6 C without making what appear to be wholly unrealistic exaggerations about the uncertainties involved. This represents a significant lowering of the previously-estimated bound.

OK some intersting stuff there alright - we learn that the ~2.5C IPCC value is "subjectively estimated to be likely to lie in the range of 1.5-4.5 C" and that "Based on some conservative assumptions regarding the value of independent estimates, we conclude that climate sensitivity is very unlikely (< 5% probability) to exceed 4.5 C.".

Now we are off to a really good start in looking for a quantitative exposition based on physics principles - subjective estimates and assumptions! We need look no further here if we want something based on sound physics! ... But it is good that James found a way to constrain the upper boundry a bit, as that should take some wind out of the sails of some of those prone to some of the worst AGW exaggerations.

BTW, for those that might not know, James Annan was lead author for the chapter in the latest IPCC report dealing with this stuff where he gets to cite his own papers as sources (including one paper that was not published prior to the IPCC paper publication deadline!) - hows that for being in a great position to get extra cites pointing to your own stuff!



Tung 2007 (http://www.amath.washington.edu/research/articles/Tung/journals/solar-jgr.pdf)


This paper, like the one above, does not contain a quantitative exposition based on physics principles, so no need to dig further here, however it is nevertheless an interesting read of both model derived and empirical methods of estimating climate sensitivity. The solar cycle stuff is interesting in it's own right.


Simplified explanation:
http://www.realclimate.org/index.php/archives/2007/08/the-co2-problem-in-6-easy-steps/

No help whatsoever in providing a quantitative physics based exposition of the ~2.5C warming claimed by the IPCC for 2xCO2 there either - but hey, it's a blog post on an AGW advocacy website, not a science paper!


They are accepted by the vast majority of climate scientists. If you wish to dispute them then you have the burden of proof.

You are getting your science all mixed up with politics.

The opinion of "the vast majority of climate scientists" might carry some political weight, but opinion counts for zero in the world of science where actual evidence and the scientific method rule the day.

The burdon of proof always remains with the proposers of the hypothesis at least until it can be be demonstrated reasonably sound and promoted to the level of theory. This has so far not been done for the IPCC claim of warming ~2.5C due to 2xCO2, as is tacitly admitted in that half-baked excuse for not doing so you linked to earlier.


If you have anything to dispute that article please provide it. Simply trying to poison the well will not suffice. RealClimate is run by qualified, working climate scientists. If you are claiming to have sufficient expertise to simply dismiss them, provide evidence of it.

RealClimate blog posts are not peer reviewed science by any stretch of meaning, even if some of the authors do publish in peer reviewed journals at times.

In any case, as long as Micheal Mann is held up as a credible climate scientist and his long ago discredited 'Hockey Stick' papers are held as up credible science on RealClimate instead of being taken to task by his colleques there for his demonstrated incompetence when it comes to applying statistical methodology, then RealClimate will continue to lack any real credibility.


That is not a peer-reviewed paper. It is a self-published article on a creationist's website. It argues that the long term warming trend is caused by the cyclic PDO, which is nonsense (http://www.skepticalscience.com/Pacific-Decadal-Oscillation.htm).

It is a simplified version of a paper in preparation for submission to the peer-reviwed journal GRL. It remains to be seen whether it will be accepted or not, so we will need to wait and see whether it will pass the peer review or not.

Your "creationist's" ad-hom shows just how desperate you are to avoid looking at the issues raised by Roy Spencer, who by the way is highly qualified to comment on climate issues whether you agree with him or not:


Roy W. Spencer received his Ph.D. in meteorology at the University of Wisconsin-Madison in 1981. Before becoming a Principal Research Scientist at the University of Alabama in Huntsville in 2001, he was a Senior Scientist for Climate Studies at NASA's Marshall Space Flight Center, where he and Dr. John Christy received NASA's Exceptional Scientific Achievement Medal for their global temperature monitoring work with satellites. Dr. Spencer is the U.S. Science Team leader for the Advanced Microwave Scanning Radiometer flying on NASA's Aqua satellite. His research has been entirely supported by U.S. government agencies: NASA, NOAA, and DOE.

[Source: http://www.weatherquestions.com/Roy-Spencer-on-global-warming.htm ]

How about actually addressing the issues raised?


Again, that is not peer-reviewed science. It was published in a social science journal (http://www.sourcewatch.org/index.php?title=Energy_and_Environment) that is well known for its politically motivated attacks on climate science, doubtless because it could not pass peer-review in a reputable science journal...

Stop making things up.

Energy and Environment is a peer reviewed journal regardless of whether you agree with their editorial policies or not.

Do you honestly think that linking to a politically motivated website set up for the sole purpose of the ad-hom trashing of reputations gives you any credibility?


Straw man. No climate scientists claim that CO2 is the only factor.

Stop making things up.

He did not claim that "climate scientists claim CO2 is the only factor". You appear to need to further develop your ability to comprehend what you read before commenting.


In fact it is well known that warming is expected to be greater in the arctic. See for example Holland and Bitz 2003 (http://psc.apl.washington.edu/pscweb2002/pubs/Bitzpolaramp.pdf).

Is that supposed to convince us of something?


You've got a lot of gall dismissing mainstream science with the wave of a hand and then asking us to take hogwash like that seriously. If you have any proper peer-reviewed science to support your claim, provide it. Otherwise withdraw your claim.

I have made no scientific claims that need to be either substantiated or withdrawn, and in fact to the contrary of your assertions otherwise, I am simply asking a valid question which nobody seems to be able to provide a satisfactory answer to.

parejkoj
2008-Nov-04, 06:47 PM
In any case, as long as Micheal Mann is held up as a credible climate scientist and his long ago discredited 'Hockey Stick' papers are held as up credible science on RealClimate instead of being taken to task by his colleques there for his demonstrated incompetence when it comes to applying statistical methodology, then RealClimate will continue to lack any real credibility.


I can has citation? The Hockey Stick is not broken. (http://gristmill.grist.org/story/2006/12/14/01828/236) That's just one of many discussions of the single climate reconstruction I believe you are referring to. You complain about ad hominems, and then proceed to completely insult a working climate scientist. Unless you can provide something to back up your claim that Mann et al. are "incompetent," please retract it. Do you even understand the exact claims regarding the "hockey stick" graph?

Also, it appears that you haven't read the realclimate.org link that has been provided (http://www.realclimate.org/index.php/archives/2008/09/simple-question-simple-answer-no/) about why demands for a "physical exposition" are either misguided or unreasonable. Let me try a couple of analogies using math and astrophysics:

1. "Why hasn't anyone provided a simple mathematical exposition of the proof of the four color theorem?"

2. "Why hasn't anyone provided a quantitative physical exposition of how a black hole merger remnant can receive a velocity kick of ~4000 km/s?"

The first is a somewhat different situation, but it is related in that the proof is a multi-hundred page paper that required computer-aided proof-by-exhaustion techniques. One has either the proof itself (long, difficult and with associated computer code) or second- or greater-hand summaries thereof. If neither the original paper, nor the educated-layman's descriptions will satisfy you, then nothing will.

The second is more closely related to your question. There are numerous papers discussing black hole mergers, and only recently have we been able to numerically model all the relevant physics (e.g. Baker et al. (http://adsabs.harvard.edu/abs/2008ApJ...682L..29B)). But the large kick velocities that show up in the simulations under specific conditions have no analytic counterpart: some basic estimates can be produced analytically, but the details all come from numerical simulations.

Reconnecting this to your "complaint": If the analytic estimates do not satisfy (e.g., realclimate.org and the links provided here (http://www.realclimate.org/index.php/archives/2008/09/simple-question-simple-answer-no/)), and the original papers do not satisfy (e.g., the IPCC report and associated documentation), then nothing will, and your "complaint" is rather pointless.

And your continued insistence that realclimate.org is not reliable should be backed up with some proof. Yes, their blog posts are not peer-reviewed, but they always link to the relevant peer-reviewed literature, where one can look at the details if one so wishes.

PraedSt
2008-Nov-04, 08:26 PM
For the record, my thinking is not as clear as it could be because on Wed, Thur, and Fri last week I was treated with powerful chemotheraputic drugs that are still coursing around my system for a particularly nasty form of terminal cancer, so please forgive my oversights, for which I apologise.

I'm staying well out of the way of this interesting debate, but I'd just like to say sorry to hear about your cancer Carl, I never knew. Hope you're feeling better today, and you stay ok for as long as possible.

mugaliens
2008-Nov-04, 11:31 PM
An oversight on my part ...

...I am simply asking a valid question which nobody seems to be able to provide a satisfactory answer to.

What's your point? Or question, for that matter, as both appeared to have been lost amidst the verbosity.

And I thought I was wordy... !

Carl_Smith
2008-Nov-05, 12:05 AM
I can has citation? The Hockey Stick is not broken. (http://gristmill.grist.org/story/2006/12/14/01828/236) That's just one of many discussions of the single climate reconstruction I believe you are referring to. You complain about ad hominems, and then proceed to completely insult a working climate scientist. Unless you can provide something to back up your claim that Mann et al. are "incompetent," please retract it. Do you even understand the exact claims regarding the "hockey stick" graph?

The Hockey Stick is well and truly broken, as demonstrated via the links in this list of materials including published peer reviewed papers and other submissions, op-eds, etc. (http://www.climateaudit.org/?page_id=354).


Also, it appears that you haven't read the realclimate.org link that has been provided (http://www.realclimate.org/index.php/archives/2008/09/simple-question-simple-answer-no/) about why demands for a "physical exposition" are either misguided or unreasonable.

I read the piece and commented in my previous post, which you apparently did not read:


In my experience, when someone tries to tell me physical processes are too complicated to explain with a clear quantitative physics based exposition it often means that in reality they have no idea of what theyre talking about, and having them then imply to me that I simply have to trust that they know what they are doing even though they cannot provide the maths to demonstrate their claims inspires no confidence in me whatsoever.

Even if it takes hundreds of pages of sound physics exposition to do so then so be it - there are trillions of dollars in taxpayer funds at stake here - don't you think it is high time some climate scientists pulled their fingers out and got on with the job at hand instead of just complaining because they think it is too hard?




Let me try a couple of analogies using math and astrophysics:

1. "Why hasn't anyone provided a simple mathematical exposition of the proof of the four color theorem?"

2. "Why hasn't anyone provided a quantitative physical exposition of how a black hole merger remnant can receive a velocity kick of ~4000 km/s?"

The first is a somewhat different situation, but it is related in that the proof is a multi-hundred page paper that required computer-aided proof-by-exhaustion techniques. One has either the proof itself (long, difficult and with associated computer code) or second- or greater-hand summaries thereof. If neither the original paper, nor the educated-layman's descriptions will satisfy you, then nothing will.

The second is more closely related to your question. There are numerous papers discussing black hole mergers, and only recently have we been able to numerically model all the relevant physics (e.g. Baker et al. (http://adsabs.harvard.edu/abs/2008ApJ...682L..29B)). But the large kick velocities that show up in the simulations under specific conditions have no analytic counterpart: some basic estimates can be produced analytically, but the details all come from numerical simulations.

Irelevent sidetracks from unrelated sciences - what do either four colour theorum or black holes have to do with physical atmospheric dynamics and temperature?

If the physics is sound a full physics exposition is not only possible but essential.

It simply requires a multidiscpinary team of scientists and engineers and technicians to be assembled to do both the theoretical and experimental work required to fill in all the blanks.

Given the trillions already sunk into AGW research it is a real indictment on climate science that this task has not yet been done, instead sinking millions into computer games and expecting us to swallow the results hook, line, and sinker.


Reconnecting this to your "complaint": If the analytic estimates do not satisfy (e.g., realclimate.org and the links provided here (http://www.realclimate.org/index.php/archives/2008/09/simple-question-simple-answer-no/)), and the original papers do not satisfy (e.g., the IPCC report and associated documentation), then nothing will, and your "complaint" is rather pointless.

The RealClimate piece is little more than a dressed up complaint about things being too hard for the apparently indequately trained climate scientists to do, and the IPCC ignored requests for just such an exposition to be prepared for it's latest report - of course with the same scientists being involved as both authors of the IPCC report and the writing of the papers cited by the IPCC on climate sensitivity, the irony of the apparent incestuousness of it all must be ringing bells to some.


nd your continued insistence that realclimate.org is not reliable should be backed up with some proof. Yes, their blog posts are not peer-reviewed, but they always link to the relevant peer-reviewed literature, where one can look at the details if one so wishes.

RealClimate links only to cherry picked pieces that support it's political advocacy position and dumps often unfounded criticism on material that does not agree it's political position. This type of nonsense is pure politics and has nothing whatsover to do with science, and the climate scientists indulging in such gutter tactics ought to be ashamed of the way they are trashing the reputation of their own field by doing do.

mugaliens
2008-Nov-05, 10:00 PM
I think I've deciphered that AGW stands for "anthropological global warming," or the portion of global warming which is due to man's operations on our planet.

parejkoj
2008-Nov-06, 01:19 AM
mugaliens: Yup. Sorry, if I didn't properly define my acronyms... I try, but some slip through.


The Hockey Stick is well and truly broken, as demonstrated via the links in this list of materials including published peer reviewed papers and other submissions, op-eds, etc. (http://www.climateaudit.org/?page_id=354).

I find it rather amusing that you cite McIntyre and McKitrick (M&M) as completely trustworthy sources while ignoring both the IPCC and realclimate.org, both of which are populated with actual climate scientists.

M&M did point out a flaw in one aspect of the statistical analysis that Mann et al. used; no-one disputes this. But, just so I know where you stand:

1. Do you understand what that flaw is? Could you describe it in a couple of paragraphs?

2. Do you know what Principal Component Analysis is, and why the details of it matter here?

3. Do you understand that the particular flaw M&M described does not affect the results of Mann et al., and that their results stand independent of that particular analysis method?

4. Do you also understand that other independent groups have redone the analysis and have shown that the conclusions of Mann et al. do hold as stated, and that M&M's particular version of the climate reconstruction is incorrect? These independent results have themselves been published in various peer reviewed journals, most of which are both more prestigious and more relevant to climate science than either GRL or E&E.

5. And finally, are you aware that your method of "attacking" climate science and scientists is both insulting and pretty much a textbook version of the type of responses that pages like this (http://gristmill.grist.org/skeptics) were created to counter? You seem to think you are adding something new to the "debate", but every point you bring up (including the completely nonsensical ones: see below!) has already been responded to elsewhere...


Irelevent sidetracks from unrelated sciences - what do either four colour theorum or black holes have to do with physical atmospheric dynamics and temperature?

If the physics is sound a full physics exposition is not only possible but essential.

They were analogies, and are completely relevant. Perhaps you should think on them, and consider how both they are relevant and why they are also unreasonable, like your request.

And anyway, why don't you answer my questions? Where is the "full physics exposition" for the kick velocities for black holes? The physics should be sound (general relativity + magneto-hydrodynamics), so why aren't those lazy "astronomy advocates" doing the hard work of providing a "full physics exposition"?

If you don't understand why the analogies are relevant, then I have nothing more to say here.


It simply requires a multidiscpinary team of scientists and engineers and technicians to be assembled to do both the theoretical and experimental work required to fill in all the blanks.

Funny that you describe it that way, since that's exactly what the IPCC is...


Given the trillions already sunk into AGW research...

WTF? Trillions? What? I can haz citation? Because, in addition to insulting working climate scientists, you also appear to be just making things up.

orionjim
2008-Nov-06, 02:00 AM
mugaliens: Yup. Sorry, if I didn't properly define my acronyms... I try, but some slip through.

[...]

WTF? Trillions? What? I can haz citation? Because, in addition to insulting working climate scientists, you also appear to be just making things up.

My Bold.

You missed another acronym. What does this mean?

parejkoj
2008-Nov-06, 02:38 AM
mugaliens: Yup. Sorry, if I didn't properly define my acronyms... I try, but some slip through.

[...]

WTF? Trillions? What? I can haz citation? Because, in addition to insulting working climate scientists, you also appear to be just making things up.
My Bold.

You missed another acronym. What does this mean?

Ahem... that would be net-speak for, erm, What the Frak... (http://en.wiktionary.org/wiki/WTF)

timb
2008-Nov-06, 06:56 AM
WTF? Trillions? What? I can haz citation? Because, in addition to insulting working climate scientists, you also appear to be just making things up.

Zimbabwe dollars, perhaps.

Carl_Smith
2008-Nov-06, 12:43 PM
I find it rather amusing that you cite McIntyre and McKitrick (M&M) as completely trustworthy sources while ignoring both the IPCC and realclimate.org, both of which are populated with actual climate scientists.

I find it rather amusing that you think that RealClimate and the IPCC are credible science sources whilst implying that the expert mathematician and statistician Steve McIntyre and his co-author Professor Ross McKitrick are both untrustworthy, apparently on the basis they are not "actual climate scientists".

How many worthy scientists that have other areas of expertise have you just insulted?


M&M did point out a flaw in one aspect of the statistical analysis that Mann et al. used; no-one disputes this. But, just so I know where you stand:

1. Do you understand what that flaw is? Could you describe it in a couple of paragraphs?

The algorithm used was flawed because it mines for hockey stick shapes regardless of data sources fed in, and as long as there is at least one hockey stick shaped series in the collection fed in it will dutifully produce a hockey stick! M&M also demonstrated that sets of red noise pseudo-data do just as well at producing hockey sticks as bristlecone pine and foxtail tree ring series do.


2. Do you know what Principal Component Analysis is, and why the details of it matter here?

Yes I do know what Principal Component Analysis is - do you?

It matters because Mann modified the PCA method to a novel and untested one that mines for the hockey stick shapes while discarding the higher level principle components of far greater significance in normal PCA analysis to instead greatly exaggerate the significance of PC4 (Mann's PC1). He provides no references that actually back up his novel approach, and even experts in the PCA field cannot fathom what Mann was really trying to do when he botched it.


3. Do you understand that the particular flaw M&M described does not affect the results of Mann et al., and that their results stand independent of that particular analysis method?

Claiming to get the right answer from a demonstrably flawed methodology is not science, it is wishful thinking. The results do not and can never stand independent of the method used to produce them. To claim otherwise is nonsense and shows you have no understanding of the scientific method. Try that one on in the ATM section here and see how far you get.


4. Do you also understand that other independent groups have redone the analysis and have shown that the conclusions of Mann et al. do hold as stated, and that M&M's particular version of the climate reconstruction is incorrect? These independent results have themselves been published in various peer reviewed journals, most of which are both more prestigious and more relevant to climate science than either GRL or E&E.

Many of the studies you refer to reuse Mann's PC1 as one of their proxies, and the people involved are co-authors with Mann - how does that constitute independence?

Others recycle exactly the same unreliable bristlecone pines and foxtail data sets that the NSA recommends not be used for temperature reconstructions but that Mann and his mates seem to find too tempting to resist cherry picking for inclusion because they contain hockey stick shapes.

Some also refuse to use updated proxies that diverge from the older ones they still insist on using, while some others truncate the newer data by chopping off the part that reveals the divergence.

The updated proxies in many cases show that the correlation between tree rings and temperature breaks down in the warmer decades later in the 20th century in many tree species - in dendrochronological circles this is known as "the divergence problem" and is the subject of much active research.

M&M never did do a climate reconstruction, but they did check for the robustness of including and excluding various proxy data sets, finding that Mann was less than forthcoming about his results. They also applied a standard textbook PCA analysis to the full set of proxies and various combinations, one example of which is sometimes claimed by the ignorant to be an M&M reconstruction.

BTW, journal reputation may count in political circles, but it counts for zero in science. It is the soundness, replicability, and methodological validity of the content that actually matters.


5. And finally, are you aware that your method of "attacking" climate science and scientists is both insulting and pretty much a textbook version of the type of responses that pages like this (http://gristmill.grist.org/skeptics) were created to counter? You seem to think you are adding something new to the "debate", but every point you bring up (including the completely nonsensical ones: see below!) has already been responded to elsewhere...

Asserting rubbish does not make it correct. I asked a simple valid question, and no one here appears to be able answer it. Instead, lame excuses and changes of subject are being used to avoid the issue.


They were analogies, and are completely relevant. Perhaps you should think on them, and consider how both they are relevant and why they are also unreasonable, like your request.

And anyway, why don't you answer my questions? Where is the "full physics exposition" for the kick velocities for black holes? The physics should be sound (general relativity + magneto-hydrodynamics), so why aren't those lazy "astronomy advocates" doing the hard work of providing a "full physics exposition"?

If you don't understand why the analogies are relevant, then I have nothing more to say here.

Asserting rubbish does not make it any more relevant. I asked a simple valid question, and no one here appears to be able answer it. Instead, lame excuses and changes of subject are being used to avoid the issue.


If the physics is sound a full physics exposition is not only possible but essential.

It simply requires a multidisciplinary team of scientists and engineers and technicians to be assembled to do both the theoretical and experimental work required to fill in all the blanks.


Funny that you describe it that way, since that's exactly what the IPCC is...

Stop making things up.

The IPCC is a collection of meeting-junket loving scientists, representatives of NGO's, and political appointees, that every so often come together to sit around in expensive venues in exotic locations choosing what science they want to include in their reports. The do not do much in the way of IPCC commissioned experimental science, and neither do they perform due diligence checks on data sets or methodologies used in scientific papers they choose to cite, instead simply relying on their own opinions of what they think should be included or excluded, often even blatantly citing their own work while simply ignoring or dismissing without justification anything that contradicts their opinions.

They also summarily dismissed many of the comments from the 'expert reviewers' without scientific reasons even being given for doing so in the majority of cases.


WTF? Trillions? What? I can haz citation? Because, in addition to insulting working climate scientists, you also appear to be just making things up.

Ah yes ... my bad ... I apologize ... chemo brain again ... I meant billions, not trillions:

http://www.aaas.org/spp/rd/ccsp08cht.gif (http://www.aaas.org/spp/rd/ccsp08p.htm)

- which is still a staggering amount of money for such poor results.

The trillions number is for upcoming spending on chasing windmills and other nonsense.

Anyway, it looks like there is nothing worthwhile going to come from my question here, so there is little point continuing to waste more of my valuable time.

In any case, whilst I have enjoyed spending some time being distracted from my own issues for a few hours here and there over the last few days, my life is precious to me, and I need to get back to focussing on more important things such as beating the cancer that is trying to kill me.

ggchuck
2008-Nov-06, 08:43 PM
I should not have included "AGW" in my original question. Though AGW is the stimulus, my question is actually more basic and just about the greenhouse effect. Global warming and mankind's contribution are two addidional distinctly different subjects. It did lead to an interesting question by Carl_Smith that may be beyond the ability of this forum to provide to his satisfaction.

I would like to thank grant hutchison, Ronald Brak, mugaliens, Disinfo Agent, dmr81, and parejkoj for their time in their efforts to educate me. I've been inactive for several days and have not had a chance to individually address each of their posts. I admit, I haven't had the time to digest much of the information linked to. As I try to make sense of it, more questions arise. Let me summarize what little I think I know about the greenhouse effect and ask some questions.

FromThe CO2 problem in 6 easy steps (http://www.realclimate.org/index.php/archives/2007/08/the-co2-problem-in-6-easy-steps/) (a source that Carl has little regard for but is written at my level of understanding), the first step addresses my question... not so much of how it works, but how to deduce the effect.

Step 1: There is a natural greenhouse effect.

The fact that there is a natural greenhouse effect (that the atmosphere restricts the passage of long wave (LW) radiation from the Earth's surface to space) is easily deducible from i) the mean temperature of the surface (around 15C) and ii) knowing that the planet is roughly in radiative equilibrium. This means that there is an upward surface flux of LW around \sigma T^4 (~390 W/m2), while the outward flux at the top of the atmosphere (TOA) is roughly equivalent to the net solar radiation coming in (1-a)S/4 (~240 W/m2). Thus there is a large amount of LW absorbed by the atmosphere (around 150 W/m2) - a number that would be zero in the absence of any greenhouse substances.

If I understand this right, the greenhouse effect is calculated by having two known radiation values. The input radiation from the sun is ~240W/m2 (it is 235 in an Energy budget diagram (http://www.cgd.ucar.edu/cas/papers/bams97/fig7.gif) figure I found) and the average surface radiation from the earth of ~390W/m2 (calculated by the equation... sigma*T^4~390W/m2:T=15C = 288.15K). To find the temperature without the greenhouse effect, a simple ratio using the fourth roots of 240 and 390 results in: T2=288.15K*3.94/4.44=255.7K:: Hence Tdif ~33C between the case of with and without greenhouse effect as advertised.
The questions:
-Is my interpretation correct? Is this the way the greenhouse effect is calculated?
-From the energy budget diagram 107W/m2 is reflected. How is this determined, and more importantly, what is the precision of the estimate?
-How valid is the surface radiation figure of 390W/m2? Is an average earth temperature of 15C a valid way to compute this or should the estimate be a sum of multiple measurements and temperatures? What is the range that this estimate encompasses?
-Does the surface of oceans/lakes only radiate in the longer wavelengths? If so, does it matter in the results of greenhouse effect?

In the paper by Gerhard Gerlich & Ralf D. Tscheuschner (http://arxiv.org/PS_cache/arxiv/pdf/0707/0707.1161v3.pdf) I linked to earlier (and criticized by several members), they maintained that both the equation I used above and the energy budget diagram I used were both invalid. In sections 3.7.3 thru 3.7.5, they maintain that other factors are involved concerning the calculation and their results deviated from the accepted value by over 100C indicating a fundamental flaw in either their assumptions/conclusions or the way surface radiation is treated.
-Since my eyes glaze over at the math, I have no way of knowing if they have a valid point or not. Does anyone here have the background to understand what they are getting at and if their point is valid or not?

Also in section 3.7.2, G&T discount the validity of the budget diagram I used. I know nothing of Feyman diagrams or Kirchhoff node rules, so their explanation made no sense to me. If someone here can interpret what they are saying, I would be interested if that has an effect on my conclusions stated above.

Ken G
2008-Nov-06, 09:40 PM
-Is my interpretation correct? Is this the way the greenhouse effect is calculated?Yes, although there is a calculation that has to go into the average temperature. All averages require a definition for how they are calculated. One could not, for example, simply take an area-weighted average of T. Much closer would be to take an area-weighted average of T4, and then take the fourth root at the end. That would still not really be quite right, because the Earth is not a "blackbody". The best way would be to actually measure the energy that the Earth is radiating-- but then you don't need the average temperature, as you already have what you want, the average energy rate.

But the bottom line is, this all depends on the desired level of precision in the answer. Any average temperature is just going to be a kind of proxy, in units we understand, for a radiation quantity. If actual temperatures are being measured, errors are being incurred, but one might hope that the errors are not too large to defeat the overall conclusion. (Note, for example, that we don't really care what temperature the Earth would be if there were no greenhouse gases, we want to know how much the temperature would change, and a 10% error in a change is not the problem that a 10% error in a temperature would be.)

In the paper by Gerhard Gerlich & Ralf D. Tscheuschner (http://arxiv.org/PS_cache/arxiv/pdf/0707/0707.1161v3.pdf) I linked to earlier (and criticized by several members), they maintained that both the equation I used above and the energy budget diagram I used were both invalid. In sections 3.7.3 thru 3.7.5, they maintain that other factors are involved concerning the calculation and their results deviated from the accepted value by over 100C indicating a fundamental flaw in either their assumptions/conclusions or the way surface radiation is treated.The reasoning that goes into equation (83) is, quite frankly, astoundingly obviously flawed. Perhaps their mathematical skills outstrip their simple common sense. The calculation you see there applies to a planet with no atmosphere and no thermal inertia. By that I mean, it applies for a blackbody (if epsilon=1) whose surface temperature instantly equilibrates with the external irradiation. In particular, the temperature is absolute zero over half the object! Why on Earth they think this has any relevance whatever to the Earth is completely beyond me-- it isn't even relevant to rapidly rotating airless planets and is hardly applicable even to slow rotators like Mercury and our Moon.

What is actually happening is, the greenhouse effect calculation that you alluded to above assumes the heat of the Sun is shared more or less equally over the Earth, either because of the atmosphere, or because daytime heat is stored overnight in the surface layers, or some combination thereof. Is this correct? Well, just ask your experience-- how much does the temperature vary over the planet? In daytime in the Sun, it might be 310 K in some places, and 250 K in others. So that's not precisely constant, as the simple 1/4 coefficient they criticize does indeed require.

However, over a vast majority of the planet, the variation is more like between 270 K and 300 K, i.e., is about 10%. Is that an error if it is not included? Certainly. Is it a big error? Certainly not. Is it comparable to the absurd errors they invoke when they compare to a model where the planet is at 0 K over half its surface? You bet it is not-- the comparison they make is completely meaningless. How ironic they think that the meaningless calculation they use to get equation (83) is in any way capable of establishing that the greenhouse effect calculations are the meaningless thing here!


-Since my eyes glaze over at the math, I have no way of knowing if they have a valid point or not. They do not, and it requires no mathematical expertise to see that, really. Just an understanding of how to extract the assumptions that go into an integral-- when the authors are careful to obscure those assumptions in their text. It is almost as though they are joking, or are attempting to prevaricate-- I cannot believe they don't see the facts as I report them above.

Now, it's possible they would say, "but the greenhouse effect is a radiative effect, so you are not allowed to invoke either atmospheric sharing from day to night, which is convective, or thermal inertia in the ground and oceans." To that I answer, "oh yes you can, if they are in fact happening, you can quite easily include them to a good approximation in a greenhouse calculation-- and that is precisely what greenhouse calculations do."


I know nothing of Feyman diagrams or Kirchhoff node rules, so their explanation made no sense to me. If someone here can interpret what they are saying, I would be interested if that has an effect on my conclusions stated above.Oh yes, I can certainly interpret what they are saying, and it is absolute and complete hogwash (you know I don't mince words, but neither do I use that word lightly). They simply overlook what the arrows actually do mean in that diagram-- they are fluxes (energy per second, whether per area or not is irrelevant), not intensities! That is clear enough from their very units, which are not the units of intensities.

Unbelievably, the paper's argument is that if the arrows were intensities (which have a directional meaning, so are per angle), one could not assert energy conservation. Yes, that's true-- which is why the arrows are fluxes, where you can assert energy conservation. How that elementary point eludes them is nothing short of shocking-- again I am tempted to conclude they are either joking or prevaricating. Surely someone has pointed out this fact, it would come in the first week of a semester-long course in introductory radiation transport.

If you think it must take a lot of gall to drop mathematical profundities like Kirchoff nodes and Feynman diagrams in the middle of an argument that boils down to "I don't know the difference between a flux and an intensity", then I would have to completely agree. Perhaps the lesson is, some people can try to baffle you with you-know-what by name-dropping, but it doesn't mean they are not saying pure nonsense.

Having said all this, I do want to point out that G&T do make one valid point-- one does have to look carefully at what simplifying assumptions are being made, and watch out for the potential errors that might accumulate. It is human nature to simplify, but we need experts to know the difference between a simplification used to explain something, and an over-simplification that invalidates a quantitative conclusion. I am confident the experts do know those differences, though may at times make approximations that could ultimately call the results into question. That happens in science all the time, it is a constant issue that is always being re-examined. But one thing is clear: G&T are not the people to trust to do that type of examination, as they exhibit not a particle of basic common sense in their overly mathematically shrouded arguments.

neilzero
2008-Nov-06, 11:56 PM
ggchuck and I share an incomplete understanding. Perhaps slightly helpful is the temperature falls to minus 100 f at the South Pole shortly before sunrise after 4 months of total darkness other than the stars, the arora and an occasional appearance of the moon. It would be even colder except there is a polar down draft which heats, by compression, the falling air as it descends near the pole. This is hot air that rose in thermals near the equator a month or two earlier. It has been radiating long infrared photons into space while it spiraled though the upper atmosphere in the southern jet stream and higher. Green house gases capture some of these long wave length photons which would otherwise escape into space. Since the green house gases are much less than 1% of our upper atmosphere, I agree, most of the out-bound photons do escape. Neil

ggchuck
2008-Nov-08, 05:49 AM
Thanks for the response Ken. I appreciate the time you spent going over a paper that I know you disdain (not that it deters me from referring to it again).

But the bottom line is, this all depends on the desired level of precision in the answer.I'm not sure that it is the bottom line... let me explain with a personal example. When I was in grade school, my teacher told me PI = 22/7. I believed I knew how to calculate PI to any precision I wished. Obviously, it was good enough for applications at that level, but it is coincidence that the ratio approximates PI. The ratio was found only because it was known that it was close to PI. To continue the analogy, you've answered my question that I am correctly dividing 22 by 7, but not that I'm really calculating PI. So the question remains; is the calculation a valid way to calculate the greenhouse effect or is it just a coincidence that it gives an approximation to results obtained by other methods?


The reasoning that goes into equation (83) is, quite frankly, astoundingly obviously flawed. Perhaps their mathematical skills outstrip their simple common sense. The calculation you see there applies to a planet with no atmosphere and no thermal inertia. By that I mean, it applies for a blackbody (if epsilon=1) whose surface temperature instantly equilibrates with the external irradiation. In particular, the temperature is absolute zero over half the object! Why on Earth they think this has any relevance whatever to the Earth is completely beyond me-- it isn't even relevant to rapidly rotating airless planets and is hardly applicable even to slow rotators like Mercury and our Moon. I was thinking they calculated it for epsilon=.7, though I'm not sure where they got that value. More important, I got a different point from their calculations. I thought they were pointing out why the equation (70) was invalid by doing the calculation the 'correct' way by deriving (83) and showing that even when done 'right' the answer was meaningless. They get around to the rotating globe in section 3.7.8.

They are not claiming to be calculating the greenhouse effect, they are attempting to show that current assumptions and calculations are in error. As you mentioned above, precision does play a part. If the methods they challenge are 'close enough,' then there is no need to reject them. But if there is no 'feel' for the precision, then finding unknown quantities by their use can be misleading.


Oh yes, I can certainly interpret what they are saying, and it is absolute and complete hogwash (you know I don't mince words, but neither do I use that word lightly). They simply overlook what the arrows actually do mean in that diagram-- they are fluxes (energy per second, whether per area or not is irrelevant), not intensities! That is clear enough from their very units, which are not the units of intensities.It's good to hear that about the only thing that kinda makes sense to me is valid (imprecise as it is). However, in defense of G&T, they listed several possible interpretations, including fluxes. Unlike the chart I linked to that had units, the one they referenced only had percentages and a percentage chart would necessitate addressing other possibilities for the arrows.

I have to admit, I don't understand their argument about fluxes either:
2. [Climatologic radiation balance diagrams] cannot represent sourceless fluxes, i.e. a divergence free vector fields in three dimensions, since a vanishing three-dimensional divergence still allows that a portion of the field goes sidewards;

ggchuck
2008-Nov-08, 06:01 AM
[The South Pole] would be even colder except there is a polar down draft which heats, by compression, the falling air as it descends near the pole. This is hot air that rose in thermals near the equator a month or two earlier. It has been radiating long infrared photons into space while it spiraled though the upper atmosphere in the southern jet stream and higher. Green house gases capture some of these long wave length photons which would otherwise escape into space. Since the green house gases are much less than 1% of our upper atmosphere, I agree, most of the out-bound photons do escape. NeilI'm not sure I understand what you are getting at here or if I'm interpreting your post correctly. It seems that 99% of the air coming from the equator would tend not to radiate the heat. Only the 1% greenhouse gases would lose heat by radiation and rely on conduction from the other gases or ground radiation to regain some of that heat.

Ken G
2008-Nov-08, 03:10 PM
I appreciate the time you spent going over a paper that I know you disdain (not that it deters me from referring to it again).You should be deterred from referring to it again. I have pointed out why the paper's argument (in that section at least-- I didn't read the others, but have little hope there) is actually complete garbage. Why you would want to refer to a paper that makes utterly spurious arguments (and not according to my opinion, but according to a precise argument I gave), I surely don't know.
So the question remains; is the calculation a valid way to calculate the greenhouse effect or is it just a coincidence that it gives an approximation to results obtained by other methods? The answer to that is, physics is not mathematics. There is only one Pi-- but there are many physical theories. The way physics works is, you choose your assumptions. Not just occasionally, but every time, you have no choice. So it's exactly like picking the precision you want-- that's all part of the assumptions you make. There is no way to make a physical calculation any other way, greenhouse effect or any other.

The calculation you refer to does make several key assumptions-- which are that the Earth has a constant temperature over its surface, and that it has a constant albedo (greyness, in the article's term). Is that exactly true? Hardly, just like the not-exactly-true assumptions that go into every single other physical calculation you have ever seen in your lifetime. Are the assumptions good enough? That depends entirely on the desired accuracy. The calculation you refer to is more an explanatory calculation than it is the best we can do. I have no doubt that climatologists use a more sophisticated version in their actual research, but that calculation does serve to capture the essence of the result. This is also not uncommon in science-- the public-explanation level calculation makes more rudimentary assumptions than the research-level calculations, but this does not invalidate either one. That's just how science is done.


I was thinking they calculated it for epsilon=.7, though I'm not sure where they got that value.It makes no difference what epsilon is, the calculation is equally irrelevant to the Earth for any epsilon, precisely for the reason I gave-- half their Earth in that calculation is at a temperature of absolute zero. Does that sound relevant to anything worth publishing in a paper on the greenhouse effect? I certainly don't think it is.


More important, I got a different point from their calculations. I thought they were pointing out why the equation (70) was invalid by doing the calculation the 'correct' way by deriving (83) and showing that even when done 'right' the answer was meaningless. What I am telling you is that there is no such thing as the "right" way to do a calculation, there are only the assumptions you make. The assumptions made in the calculation they criticize is that the Earth is all at the same temperature and has the same albedo. The assumptions made in the calculation they use to criticize it is that half the Earth is at absolute zero. Why they think the absurd assumptions in the latter are in any way relevant to the decent-but-not-exact assumptions in the former is the subject of my derision about the paper.


They get around to the rotating globe in section 3.7.8.A little late, as they have already used the irrelevant argument as if it were relevant. Look at the preposterous statement in section 3.7.5:
"The difference of 33 C [which comes from the reasonable assumptions] is attributed to the natural greenhouse effect. As seen in equation (83) the correct [!] averaging [which comes from the absurd assumptions] yields a temperature of -129 C."
Now that's just garbage, really it is. The section goes on to say the equally pointless "Neither is there a global radiation balance, nor a global radiation budget, even in the mean-field limit". I'm sorry, but these authors apparently have not heard of the scientific usefulness of conservation of energy. And they may be interested to learn that the crucial concept of "thermodynamic equilibrium" is always an approximate notion. I see them as pure mathematicians who are very ill-equipped to understand how physics works.


They are not claiming to be calculating the greenhouse effect, they are attempting to show that current assumptions and calculations are in error.By making far more inaccurate assumptions-- how does that do anything of the sort? It's basic bad logic.

Just for the record, equations (83) and (88) are true, and also quite obvious to anyone with any reasonable facility with the concepts of averaging of algebraic quantities. I have no doubt that theoretical climatologists are well aware of that issue, even if they've never met "Holder". I certainly am. In fact it is embedded in my comments earlier.


It's good to hear that about the only thing that kinda makes sense to me is valid (imprecise as it is). However, in defense of G&T, they listed several possible interpretations, including fluxes. There are no "possible interpretations", it is the fluxes that are being talked about, pure and simple. In the list I criticized, fluxes were not even present. If they made some other list elsewhere, fine, but there's no need for any lists-- it's fluxes, and everyone else knows that.

They create a tempest in a teacup there, and make pointless statements about the absence of a global energy balance involving fluxes. They seem to simply be unaware of the basic requirement in all scientific calculations-- the need to make approximate assumptions, then test their validity. People who simply say "but that's not exact" and then supply vastly more inaccurate assumptions in their place, are actually not saying anything at all of any scientific value. That's just the truth.


Unlike the chart I linked to that had units, the one they referenced only had percentages and a percentage chart would necessitate addressing other possibilities for the arrows.Only for someone who doesn't understand basic energy conservation. For anyone who does, the arrows obviously represent fluxes.


I have to admit, I don't understand their argument about fluxes either:I understand the argument fine, which is why I know it is irrelevant. Again they are simply unaware of the need for basic, and here quite accurate approximations. The approximation here is that the surface of the Earth is locally a plane, so that one can use a flux in the plane-parallel approximation to describe the energy leaving the Earth. That is perfectly fine, their objection is pointless.

ETA: I should address your point that they go on in later sections to talk about rotation. The reasoning that leads to equation (94) is a classic example of the pervasive problems with the entire paper. Equation (94)assumes that the Earth can conduct heat, but has no mass. In short, there's no thermal inertia-- we don't need to track the history of how it came to its current temperature. This is only a reasonable assumption to make depending on what value of the crucial lambda parameter is being chosen. In fact, equation (94) is all about lambda-- it looks mathematically complicated, but it's actually quite simple, except that we don't know what to use for lambda. No worries, we have to make idealizations like that all the time, this is the point. But note one thing they fail to note-- if you take lambda=infinity, you get the very same greenhouse calculation they reject (T=constant), and if you take lambda=0, you get the calculation they do in 3.7.5 to criticize the lambda=infinity calculation. In other words, they seem surprised that if you vary lambda from 0 to infinity, you get the variations in the outcomes that they summarize in their tables. Personally, I don't find it surprising at all that varying a key parameter from zero to infinity could have a significant effect, and how that somehow invalidates either calculation is beyond me. The real question is, is lambda more like zero, or more like infinity? The answer is, it's more like infinity, because of the efficiency of moving heat around.

Now I realize they go on to include thermal inertia in the next section, but there you find just more of the same-- a lack of understanding of the basic physical meaning of the equations they manipulate. That flaw pervades the paper, and invalidates their conclusions, even though they do know how to solve equations-- and that's all they know how to do.

mugaliens
2008-Nov-08, 10:46 PM
I should not have included "AGW" in my original question. Though AGW is the stimulus, my question is actually more basic and just about the greenhouse effect. Global warming and mankind's contribution are two addidional distinctly different subjects.

Actually, I'm glad you did, as I see from the historical record a very close correlation between global warming and sunspot activity, long before AGW was anything but a tiny fraction of any global warming trend.

parejkoj
2008-Nov-09, 04:48 PM
Actually, I'm glad you did, as I see from the historical record a very close correlation between global warming and sunspot activity, long before AGW was anything but a tiny fraction of any global warming trend.

Yes (http://gristmill.grist.org/story/2006/12/28/090/30666), but (http://www.realclimate.org/index.php/archives/2005/07/the-lure-of-solar-forcing/) no (http://www.realclimate.org/index.php/archives/2005/08/did-the-sun-hit-record-highs-over-the-last-few-decades/).

mugaliens
2008-Nov-09, 10:45 PM
Yes (http://gristmill.grist.org/story/2006/12/28/090/30666), but (http://www.realclimate.org/index.php/archives/2005/07/the-lure-of-solar-forcing/) no (http://www.realclimate.org/index.php/archives/2005/08/did-the-sun-hit-record-highs-over-the-last-few-decades/).

Yes: Makes an apparently false assumption that sunspot's affect on global warming and cooling is through irradiance.

But: "Thus, my contention that solar doesn't explain much of the variability in this record isn't valid. It could explain anything from 5 to 40% (with unknown error bars). Sorry for any confusion."

No: "Regardless of any discussion about solar irradiance in past centuries, the sunspot record and neutron monitor data (which can be compared with radionuclide records) show that solar activity has not increased since the 1950s and is therefore unlikely to be able to explain the recent warming."

For the last, I have the same comment as the "Yes portion."

ggchuck
2008-Nov-11, 12:56 AM
You should be deterred from referring to it [G&T paper] again.You have convinced me that the paper has enough flaws so any information or conclusions from it are suspect at best. Thanks for going over the portions that I was looking at.

Back to the equation that I pulled from the 'six easy steps' paper explanation. From that, it seems like the global greenhouse effect is not dependent on the heat retention properties of the greenhouse gases (GHG), but relies on the GHG's ability to re-radiate heat to the ground. In summary (and ignoring precision), for a specific temperature the earth's surface radiates a known amount of radiation. The introduction of GHG effectively increases the heat input to the surface by re-radiation and heats the surface until the planet is warm enough to radiate away that re-radiated radiation as well as the solar input.

Is that what really happens? This essentially shows the tennis ball analogy posted earlier isn't a valid way to understand the concept of the greenhouse effect.

grant hutchison
2008-Nov-11, 01:18 AM
In summary (and ignoring precision), for a specific temperature the earth's surface radiates a known amount of radiation. The introduction of GHG effectively increases the heat input to the surface by re-radiation and heats the surface until the planet is warm enough to radiate away that re-radiated radiation as well as the solar input.

Is that what really happens? This essentially shows the tennis ball analogy posted earlier isn't a valid way to understand the concept of the greenhouse effect.That's what happens. Although it's important to bear in mind that the energy budget at the top of the atmosphere is unchanged; the re-radiation and re-re-radiation just maintain a higher energy exchange between the surface and the lower layers of the atmosphere, driving temperatures in that region to a higher equilibrium.
(And, oddly, that's exactly what the tennis-ball analogy was designed to show. :))

Edit: Notice how, in your energy budget diagram (http://www.cgd.ucar.edu/cas/papers/bams97/fig7.gif), the surface of the Earth is receiving 492 W.m-2 in solar radiation and back-radiation from the atmosphere, and is disposing of the same amount in the form of thermals, evaporation and radiation. Up aloft, only 235 W.m-2 is being radiated to space, to balance the 235 W.m-2 of solar radiation which has got into the system after avoiding reflection. From the outside, Earth looks like a much cooler body than it does at the surface.

Grant Hutchison

Ken G
2008-Nov-11, 02:03 AM
In summary (and ignoring precision), for a specific temperature the earth's surface radiates a known amount of radiation. The introduction of GHG effectively increases the heat input to the surface by re-radiation and heats the surface until the planet is warm enough to radiate away that re-radiated radiation as well as the solar input.Yes, that's it. One way you can look at it is that when you stand outside on a sunny day, you get radiant heat from three sources-- the Sun, the ground, and the greenhouse gases in the air, instead of just the first two. That's also what the tennis ball analogy is saying, that the Sun and ground are like a "single volley" in tennis, and adding the greenhouse gases is like playing a "rally" instead of a service-return winner. Your word "re-radiation" shows you understand that, so I'm not clear on your issue with the tennis analogy, other than that it can be a pretty frustrating game.

ggchuck
2008-Nov-11, 05:18 PM
...the re-radiation and re-re-radiation just maintain a higher energy exchange between the surface and the lower layers of the atmosphere, driving temperatures in that region to a higher equilibrium.
(And, oddly, that's exactly what the tennis-ball analogy was designed to show. :))

...I'm not clear on your issue with the tennis analogy, other than that it can be a pretty frustrating game.
I know there are always flaws with analogies. The fact that I don't understand this one is either a flaw in the analogy that I can't get around or a flaw in my understanding of the concepts of radiation, reflection, heat, and photons.

To me the bouncing of balls is representative of reflection, not radiation. The reflected energy is not 'heat' until it comes to rest. A mirror can reflect different intensities of energy without having to increase its temperature. For example: A base mirror reflects incoming light toward a smaller mirror that is large enough to only intercept half of it. The smaller 'atmospheric' mirror (probably convex) reflects that half back; half of it spreading spreading over the face of the base mirror and the other half lost. Because of the atmospheric mirror, there are more photons now bouncing around, but neither mirror will get warmer.

If the concept is as I understand it and for the tennis ball analogy to work, the balls would have to be thrown rather than hit. The ground player (and the atmospheric player) would be standing in a field of balls, reaching down picking one up, and throwing it. If either player is unable to throw away more balls than comes his way, the balls around him will pile up thereby making it easier for him to grab and throw. It would be the piles of balls that relate to warming, not the number of balls in the air.

grant hutchison
2008-Nov-11, 05:49 PM
To me the bouncing of balls is representative of reflection, not radiation.OK, there's where it's going wrong for you.
The balls represent radiation. Receiving and returning a ball represents absorption and re-radiation. The need to return all received balls represents thermal equilibrium. Increase workload because of a greater through-put of balls represents reaching a higher temperature.
I did mention all this when setting up the original analogy, but perhaps I didn't work hard enough at it. :)

Grant Hutchison

ggchuck
2008-Nov-11, 07:22 PM
...The need to return all received balls represents thermal equilibrium. Increase workload because of a greater through-put of balls represents reaching a higher temperature...This is the concept that eludes me. It seems like the effect of the balls that are not returned is what raises the temperature. The way I see it, just having more balls in the air doesn't affect the heat but when they accumulate at rest a rising temperature is represented. In this analogy, the medium between the atmospheric player and the ground player doesn't register a temperature rise despite more balls passing through.

This may be due to my perception of heat vs radiation. I think of them as different, but I'm not familiar enough with those terms or the mechanics behind them to know if my concept is flawed or not. To me 'radiation' is a photon running around without a temperature of its own where 'heat' is indicated by the speed of a particle. Thinking about it, frankly, I don't know what happens when a photon encounters a molecule. Does it surrender all its energy and vanish? Are photons created when an object radiates heat? A couple of off-topic questions that should probably be asked elsewhere.

grant hutchison
2008-Nov-11, 09:19 PM
This is the concept that eludes me. It seems like the effect of the balls that are not returned is what raises the temperature. The way I see it, just having more balls in the air doesn't affect the heat but when they accumulate at rest a rising temperature is represented. Radiant energy raises the temperature of any object that absorbs it: the energy of the photons is converted to thermal energy in the motion of the molecules making up the object. That thermal motion, in turn, makes the substance emit more radiant energy. So an increase in absorbed radiant energy makes our object increase in temperature until it is emitting as much energy as it receives. Then a new equilibrium, at a higher temperature, is reached.
So the more radiant energy we measure being absorbed and re-radiated, the hotter our object is.

I believe you're thinking about objects that are not in equilibrium: that are in the process of warming up by absorbing more radiation than they emit. So in the analogy you're wanting the player to accumulate tennis balls as a marker of accumulating heat. But the player is simply moving from one equilibrium (low temperature, small number of balls in play) to another equilibrium (higher temperature, more balls in play).

Think of a classic "black body": an enclosed cavity full of thermal photons, which are constantly being emitted and absorbed by the walls of the cavity. The thermal energy of the walls is in equilibrium with the radiant energy of the photons. So the energy density of the photons is a marker for the equilibrium temperature of the walls: fewer, less energetic photons mean cooler walls. Likewise with the constant exchange of infra-red photons between atmosphere and ground. mediated by greenhouse gases.

Grant Hutchison

ggchuck
2008-Nov-11, 10:57 PM
I believe you're thinking about objects that are not in equilibrium: that are in the process of warming up by absorbing more radiation than they emit. So in the analogy you're wanting the player to accumulate tennis balls as a marker of accumulating heat. But the player is simply moving from one equilibrium (low temperature, small number of balls in play) to another equilibrium (higher temperature, more balls in play).If I am wrong and my analogy doesn't reflect what is happening, then I'm missing something basic. I see the pile of balls representing temperature and the result is indeed in equilibrium once the pile is high enough to increase the rate of returning the balls. What I feel is the weakness of the original analogy is that it doesn't provide a method for the ground player to increase the rate of returning the balls, it just states that because there are more balls coming at him, he does.


Think of a classic "black body": an enclosed cavity full of thermal photons, which are constantly being emitted and absorbed by the walls of the cavity. The thermal energy of the walls is in equilibrium with the radiant energy of the photons. So the energy density of the photons is a marker for the equilibrium temperature of the walls: fewer, less energetic photons mean cooler walls.I'm getting lost here and my ignorance of photons is getting me into trouble. Is 'energy density' the same as temperature? Are there photons that are more or less energetic than others? Would the color of the interior of the cavity have an effect on the temperature and/or the energy density?

grant hutchison
2008-Nov-11, 11:25 PM
If I am wrong and my analogy doesn't reflect what is happening, then I'm missing something basic. I see the pile of balls representing temperature and the result is indeed in equilibrium once the pile is high enough to increase the rate of returning the balls. What I feel is the weakness of the original analogy is that it doesn't provide a method for the ground player to increase the rate of returning the balls, it just states that because there are more balls coming at him, he does.I think you're in danger of spending too much time critiquing an analogy. :)
Given that you now seem to understand the physics, maybe you need to to let the analogy go?
We've established, I think, that when an object absorbs more radiant energy, it will increase in temperature until it emits as much as it receives, and then it will stop increasing in temperature: it will seek a new equilibrium. Are you happy with that?


I'm getting lost here and my ignorance of photons is getting me into troubleOK, scrub the black body cavity. The point of it was just to illustrate a surface that was in equilibrium with ambient photons, emitting as much energy as it receives, and how we can then use the photon energy as a surrogate for the cavity temperature. But if you haven't encountered black body radiation before, I fear it'll just confuse matters.

Grant Hutchison

ggchuck
2008-Nov-12, 05:23 PM
...you now seem to understand the physics...Thanks. That was what I was looking for. When both you and Ken mentioned that I interpreted the analogy wrong, I worried that though we came to a similar conclusion, my understanding of the concept was an illusion. That's why I was harping on the details.

grant hutchison
2008-Nov-12, 07:37 PM
Thanks. That was what I was looking for. When both you and Ken mentioned that I interpreted the analogy wrong, I worried that though we came to a similar conclusion, my understanding of the concept was an illusion. That's why I was harping on the details.I don't think we said you interpreted it wrongly. We just didn't know what your problem with it was.

If you are happy with this:
We've established, I think, that when an object absorbs more radiant energy, it will increase in temperature until it emits as much as it receives, and then it will stop increasing in temperature: it will seek a new equilibrium.then it's easy enough to point up where the analogy is going wrong for you.

If you choose to imagine the tennis match being played at some sufficiently small energy scale, then there is some discernible lag between the arrival of additional balls and the player returning additional balls. That's the point at which you're wanting balls to build up around the player to signify the warming process. In the analogy, you've got to come up with some sort of odd mechanism to account for the delay, and some other odd mechanism to account for why the player eventually responds to the build-up of balls. All this is required in order to shoe-horn the warming process itself into the analogy.
But at the end of the process, we have a new equilibrium: the player is once again returning as many balls as are arriving. A million balls arrive, a million are returned, there's a new thermal equilibrium. On the grand scale, the energy flux through the system is huge, the transient deficit associated with warming is small, and what counts is the shift from an old to a new equilibrium.
So we can always imagine the tennis match played on a sufficiently large scale in which the little warming episodes are swamped. On that scale, the change in temperature occurs almost instantaneously, mediated by a near-infinitesimal proportion of single tennis ball. On that scale, all we see are the equilibria, and the number of balls in the air tells us all we need to know about the temperature of the participants.
To me, that's the natural scale at which the analogy operates. If I want to know the temperature of a planet, I don't fret about the warming process itself. I just work out the equilibrium temperature at which it radiates as much energy as it receives. Understanding the equilibria lets me understand the greenhouse effect without fretting the details.

Now, if you want to make useful predictions about the time-scale of global warming, then you have to fret the details. And the details are very complicated. But that's a separate issue from just understanding how the greenhouse effect works.

Grant Hutchison

Ken G
2008-Nov-12, 09:21 PM
Yes, I think this is similar to the basic problem with the paper cited above. The paper basically said, "but none of these calculations are exactly the correct physical situation, so therefore their conclusions are no less suspect than these egregiously wrong calculations that we will now present to make this point." It is as though there is a mathematical mindset that there is "one true set of equations", and all others are "wrong", therefore the conclusions of one "wrong" equation is no better than the conclusions of any other "wrong" equation. Sadly, all equations in science are wrong, so scientists have figured out a way to deal with "shades of rightness". This causes great confusion when the shades of rightness are different for a "simple explanation" than they are for a "detailed calculation". That problem was dripping from every page of that paper. It is really as though there is something fundamental to how science is done that is being overlooked, but it's not an obvious or simple element of science-- it is almost a kind of arcane art of seeking the appropriate "degree of rightness".

I think that is also at the heart of the disconnect here between grant hutchison, who is applying a standard degree of rightness approach in science (that of considering the equilibrium), and ggchuck, who, perhaps guided by the mindset of that paper, seems worried that anything that isn't right must be wrong. This is basically the dirty little secret of science-- in real applications, we almost never know how right is right enough in any absolute kind of way, but we learn to cope anyway.

Carl_Smith
2008-Nov-13, 12:52 AM
Sorry guys, but in spite of your best efforts at describing it and putting forth analogies, I still cannot get my head around what appears to be the 'free lunch' part of the enhanced greenhouse effect.

It just seems unphysical to me, and it seems like someone is promoting something that supposedly works like this:

http://www.real-debt-elimination.com/images/IPCC_oven.jpg (http://www.real-debt-elimination.com/real_freedom/Propaganda/Global_Warming_Myth/prejudiced_authors_prejudiced_findings-2.htm)

cjl
2008-Nov-13, 07:03 AM
More like this:

Solar energy gets in. This is a constant influx of energy. This energy is radiated back out by the earth (after all, it is in thermal equilibrium). With no greenhouse gases, this is radiated straight out to space. With greenhouse gas, the energy is absorbed, and then radiated out again by the gas. However, as radiation is not a directional process, some of this radiation from the gas is actually directed back down at the surface, allowing less of the initial heat radiated by the ground to get out. As the amount out of the system must remain constant for the system to be in thermal equilibrium, the amount radiated by the ground must increase. This is the reason that the temperature goes up.

In other words, that diagram is missing a constant heat influx. It also wouldn't be a cascade effect, but rather would be an effect where the chicken in an insulated oven would reach a higher equilibrium temperature with the same heat influx as compared to a chicken in space.

Ken G
2008-Nov-13, 07:25 AM
Sorry guys, but in spite of your best efforts at describing it and putting forth analogies, I still cannot get my head around what appears to be the 'free lunch' part of the enhanced greenhouse effect.What you are missing is that the temperature of the chicken could never exceed the brightness temperature of the microwaves, which in your case, is zero. What the greenhouse effect can do, however, is get the chicken up to the brightness temperature of the microwaves, at a much lower power input to the chicken than you would need if it were not a greenhouse-encased chicken.

Getting back to the Sun, what this means is that the theoretical limit for the maximum possible greenhouse effect could heat the surface of a planet up to the surface temperature of the Sun. The best greenhouse in practice, Venus, doesn't approach anywhere near that theoretical limit.

grant hutchison
2008-Nov-13, 07:03 PM
http://www.real-debt-elimination.com/images/IPCC_oven.jpg (http://www.real-debt-elimination.com/real_freedom/Propaganda/Global_Warming_Myth/prejudiced_authors_prejudiced_findings-2.htm)Original context (http://www.real-debt-elimination.com/real_freedom/Propaganda/Global_Warming_Myth/prejudiced_authors_prejudiced_findings-2.htm) for the linked image.
My jaw dropped.

Grant Hutchison

Ken G
2008-Nov-13, 08:45 PM
Original context (http://www.real-debt-elimination.com/real_freedom/Propaganda/Global_Warming_Myth/prejudiced_authors_prejudiced_findings-2.htm) for the linked image.
My jaw dropped.Yes, that's a remarkable article, though I'm not sure if it is more remarkable as a cautionary tale about how scientists, being human beings, can get "too married" to their current understanding of reality, or a stark example of how impossible it is to advance human knowledge if any effort to do just that can instead be interpreted as a conspiracy theory. I conclude, surprisingly, that it is actually equally successful at both-- the intended purpose, and the unintended one. Unfortunately, most readers will probably only hear one message or the other-- and it will be the opposite message from the one they need to hear.

grant hutchison
2008-Nov-13, 08:58 PM
Yes, that's a remarkable article, though I'm not sure if it is more remarkable as a cautionary tale about how scientists, being human beings, can get "too married" to their current understanding of reality, or a stark example of how impossible it is to advance human knowledge if any effort to do just that can instead be interpreted as a conspiracy theory. I conclude, surprisingly, that it is actually equally successful at both-- the intended purpose, and the unintended one. Unfortunately, most readers will probably only hear one message or the other-- and it will be the opposite message from the one they need to hear.The jaw-drop was mainly in response to the list of contents in the yellow side-bar to the left of the article. This is one page of many. They appear to share a certain preoccupation.

Grant Hutchison

Ken G
2008-Nov-13, 09:53 PM
Oh, the "debt elimination" business. I have no idea how that is connected to the article. The purpose of the article seemed to be to plug the "Infinite Energy" book, and the idea that scientific breakthroughs might be imminent if the climate were less oppressive. I did not see which scientific breakthroughs specifically were going to eliminate our debt, either personal or national, but I am willing to accept they are on the whole, economically positive. Also, it seems clear that science being too open to running on and on after every flaky idea that comes along would be more detrimental than a somewhat oppressive environment to new ideas, but I will allow there there is a "happy medium" in there somewhere! Hey, maybe that happy medium would eliminate my debt?

grant hutchison
2008-Nov-13, 10:18 PM
Oh, the "debt elimination" business.I have no idea what the "debt elimination" is about. But the rest of the site is a hot-button compilation of "New World Order" conspiracy theory.

Grant Hutchison

Ken G
2008-Nov-13, 10:29 PM
I have no idea what the "debt elimination" is about. But the rest of the site is a hot-button compilation of "New World Order" conspiracy theory.
Yes, I sense the article itself is rather separate from that, but as it fits into that overall world view, they referenced it. That's a shame, because the article itself is not nearly so absurd, even if it is rather blind to the advantages of a scientific community that can actually establish what is more and what is less likely to be a productive avenue of research.

George
2008-Nov-13, 10:59 PM
I had to miss lunch today, and noticed the chicken (http://www.vermonttiger.com/content/2008/07/nasa-free-energ.html). It appears to be from James Peden (http://www.middlebury.net/op-ed/global-warming-01.html), who appears to be skeptical of man's share of the problem.