Moderated Global Warming Discussion

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Dyson in an interview by Yale Environment 360

Freeman Dyson: It’s difficult to say, “Yes” or “No.” It was reasonably accurate on details, because they did send a fact-checker. So I was able to correct the worst mistakes. But what I could not correct was the general emphasis of the thing. He had his agenda. Obviously he wanted to write a piece about global warming and I was just the instrument for that, and I am not so much interested in global warming. He portrayed me as sort of obsessed with the subject, which I am definitely not. To me it is a very small part of my life. I don’t claim to be an expert. I never did. I simply find that a lot of these claims that experts are making are absurd. Not that I know better, but I know a few things. My objections to the global warming propaganda are not so much over the technical facts, about which I do not know much, but it’s rather against the way those people behave and the kind of intolerance to criticism that a lot of them have. I think that’s what upsets me.
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Malcolm Kirkpatrick said:
I'm still trying to understand how the surface temperature can depend on anything other than solar output and the radius of the Earth's orbit.
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I'll try to take this seriously.

You would be somewhat correct to understand that the incoming solar energy depends on solar output and distance. Of course, the albedo of the planet would affect what portion of that incoming energy is reflected vs absorbed.

However, somebody with a little bit of thermodynamic knowledge might recognize that when the earth's temperature is in equilibrium, the outgoing energy must balance the incoming energy - with or without the greenhouse effect. While the dynamics are much more complex, my understanding is that the net effect of the greenhouse effect is to raise the altitude of the equilibrium point - the effective height from which the emitted energy as seen from space balances the solar input. Once equilibrium is reached, a thermal scan of earth from afar will be the same with or without the greenhouse effect - it will seem to have the same effective temperature (for a given solar output and fixed earth albedo). That effective temperature your space-borne instrument sees is NOT the temperature of the surface, but of that equilibrium point in the atmosphere (which depends on the spectral absorbsion, heating, re-emission, and reflection of many layers of surface and atmosphere). When that equilibrium point rises, the surface temperature (at an increasing distance below the equilibrium point) can also rise, even with the same solar input and the same apparent emission temperature as seen from outside.

Of course, the temperature is not currently in equilibrium - our problem is that the average surface temperature is rising towards a new equilibrium.
 
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Malcolm Kirkpatrick said:
Consider the opposition to continental drift, which ended only when a mechanism was discovered. Consider the error bars around estimates of the speed of light... [an author] quotes a colleague of Fredkin to the effect that "Most physicists are just Democrats or Republicans", meaning party-line people. Scientists are people and people are social animals.
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Scientists are of course fallible, no news there. What you miss is that unlike debates about theology, fashion or ideologies, scientific debates have the character of giving top billing to objective measurements in the end, and are thus falsifiable. The mechanisms of science amount to some algorithms for the collective pursuit of knowledge which is increasingly synchronized with physical reality due to the judicious feedback loops - such that even with individual and even much collective fallibility, we can over time get closer and closer to a true understanding.

By far the vast majority of "crackpot" scientific theories turn out to deserve the rejection they face - we celebrate the exceptions in part because of their man-bites-dog-story rarity. And what characterizes those exceptions, when a "wild" theory become mainstream consensus in science - it their grounding in objective evidence which eventually does convince the majority.

What some miss is that Global Warming is one of those cases where a small number of scientists were able to convince the rest due to some good scientific work. 50 years ago very few climate scientists would have accepted the theories of AGW, because there had not yet accumulated sufficient evidence and well-tested analysis to persuade them. That has changed - and now it's going to take a similar amount of solid evidence and analysis to persuade most climate scientists that global warming isn't happening or isn't largely due to human factors - any new theory needs to account for the massive evidence which has accumulated. And the anti-AGW folks have very clearly not created such a strong evidential case, to shift the consensus again via scientific means.

So they have shifted to trying to confuse and mislead the public, where objective evidence and the algorithms of science are not well understood or practiced (to say the least).

All it would take to shake AGW to the core would be for a "science based sceptic" to create a peer-reviewed and solid GCM which can account for the unfolding historical record without taking CO2 into account. I don't mean that would suddenly "prove" it all wrong (as there are other lines of evidence), but it would seriously shake things up and lead to a far reaching re-evaluation and the need for a new central hypothesis and new theories. But so far, all the serious GCMs wind up generally agreeing on the role of CO2, and the estimates of climate sensitivity from various sources have similar values (within error bars).

It's a lot easier to play semantic games and make unfounded assertions, than to do the hard work of providing an alternate explanation with quantitative support (like a GCM which does not require CO2 forcing to explain the observed facts).

The overall picture which the IPCC and others have assembled from vast amounts of evidence is an impressive scientific achievement. Will it have warts? Of course, and it will continue to be adjusted through the scientific process. There is nothing even vaguely competitive in the way of an alternative theory weaving together all available evidence. The critics try to pick on pieces here and there, attempting to weaken it piecemeal by attacking one bit at a time - but have made no substantial progress in that task, much less the more daunting but important one of providing some coherent alternative explanation for the whole body of evidence.
 
Malcolm Kirkpatrick said:
"That"? What did I "make up"? He said a lot of things. Which quote do you suppose matters to this discussion? Link?Dunno 'bout "can't". I'm waiting to see how far you'all go in (misre)presenting Dyson's position.
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Whatever, you obviously just have rehtoric and mis-state what Dyson said, so he think that the models thirty years ago were not accurate.

he did not say "The conclusion that AGW theorists draw from their models depends on a lot more than "basic physics", or Dyson would share the conclusions that the AGW faithful draw."

That is just your spin and mis statement, so why should his knowledge of the models 30 years ago be important?

Where id Dyson say that exactly?
 
Zeph said:
Malcolm Kirkpatrick said:
I'm still trying to understand how the surface temperature can depend on anything other than solar output and the radius of the Earth's orbit.
Click to expand...

I'll try to take this seriously.

You would be somewhat correct to understand that the incoming solar energy depends on solar output and distance. Of course, the albedo of the planet would affect what portion of that incoming energy is reflected vs absorbed.

However, somebody with a little bit of thermodynamic knowledge might recognize that when the earth's temperature is in equilibrium, the outgoing energy must balance the incoming energy - with or without the greenhouse effect. While the dynamics are much more complex, my understanding is that the net effect of the greenhouse effect is to raise the altitude of the equilibrium point - the effective height from which the emitted energy as seen from space balances the solar input. Once equilibrium is reached, a thermal scan of earth from afar will be the same with or without the greenhouse effect - it will seem to have the same effective temperature (for a given solar output and fixed earth albedo). That effective temperature your space-borne instrument sees is NOT the temperature of the surface, but of that equilibrium point in the atmosphere (which depends on the spectral absorbsion, heating, re-emission, and reflection of many layers of surface and atmosphere). When that equilibrium point rises, the surface temperature (at an increasing distance below the equilibrium point) can also rise, even with the same solar input and the same apparent emission temperature as seen from outside.

Of course, the temperature is not currently in equilibrium - our problem is that the average surface temperature is rising towards a new equilibrium.
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All true.

Alternatively, instead of discussing the thought experiments, one could do a real experiment.

Get some glass cloches and put them on the ground on a sunny day and measure the air temperature inside and outside the cloche.

I think I'll coin a phrase for the effect that makes the temperature rise inside the cloche - I wonder how "greenhouse effect" sounds...
 
Malcolm Kirkpatrick said:
Here's another question: Suppose we have a well-insulated container (double-wall thermos flask) that holds, say, 8 kilos of water at 60F. Suppose we place into the flask a 2 1 kilo glass-coated bricks of some material (metal, ceramic) that we heat to, say, 80F. Will the equilibrium temperature of the system depend in any way on the material inside the glass coat of the bricks? I suspect not but I'm willing to accept correction here.
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My previous post was directed at that.

In a similar vein to you.

Suppose we have a 3-ft square bare surface, and we have a sheet of plate glass that could cover half the area (e.g. 1.5' by 3')

We then place this glass on wooden wooden dowling so that is is about 4" above the surface and air can get around it.

We leave this in the sun of a few hours and measure the surface temperature both inside and outside the area covered by the glass.

If your contention
I'm still trying to understand how the surface temperature can depend on anything other than solar output and the radius of the Earth's orbit.
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Is correct, then the surface temperature will be the same in both situations.

The wooden dowels and lack of sides allows free movement of air in both situations.
 
Reality Check said:
And you are still wrong...
Malcolm Kirkpatrick: Species of Foraminifera could not adapt to CO2 changes that took millions of years to happen.
What do you think will happen to Foraminifera when CO2 changes over decades?
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More than 70% of all species went extinct in the Permian/Triassic mass extinction. And...here.
...a study of uranium/lead ratios of zircons from rock sequences in multiple locations in southern China[3] date the extinction to 252.28 ± 0.08 Ma; an earlier study of rock sequences near Meishan in Changxing County of Zhejiang Province, China[20] date the extinction to 251.4 ± 0.3 Ma, with an ongoing elevated extinction rate occurring for some time thereafter.
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jimbob said:
If your contention
Malcolm Kirkpatrick said:
I'm still trying to understand how the surface temperature can depend on anything other than solar output and the radius of the Earth's orbit.
Click to expand...
Is correct, then the surface temperature will be the same in both situations.

The wooden dowels and lack of sides allows free movement of air in both situations.
Click to expand...
What "contention"? How does "I'm still trying to understand" imply any conclusion whatsoever? I already said that observed temperature does NOT depend on solar output and distance alone; consider the day/night variation and the sea level to high altitude variation.
Still, this thought experiment, and lomiller's thought experiment (adding a continuous heat source to an insulated thermos flask) make a welcome departure from relentless (unmoderated) ad hominem. Thanks.
 
Malcolm Kirkpatrick said:
What "contention"? How does "I'm still trying to understand" imply any conclusion whatsoever? I already said that observed temperature does NOT depend on solar output and distance alone; consider the day/night variation and the sea level to high altitude variation.
Still, this thought experiment, and lomiller's thought experiment (adding a continuous heat source to an insulated thermos flask) make a welcome departure from relentless (unmoderated) ad hominem. Thanks.
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Edited by jhunter1163: 
Edited for Rules 0 and 12.
 
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Acleron said:
Dyson in an interview by Yale Environment 360
Freeman Dyson: It’s difficult to say, “Yes” or “No.” It was reasonably accurate on details, because they did send a fact-checker. So I was able to correct the worst mistakes. But what I could not correct was the general emphasis of the thing. He had his agenda. Obviously he wanted to write a piece about global warming and I was just the instrument for that, and I am not so much interested in global warming. He portrayed me as sort of obsessed with the subject, which I am definitely not. To me it is a very small part of my life. I don’t claim to be an expert. I never did. I simply find that a lot of these claims that experts are making are absurd. Not that I know better, but I know a few things. My objections to the global warming propaganda are not so much over the technical facts, about which I do not know much, but it’s rather against the way those people behave and the kind of intolerance to criticism that a lot of them have. I think that’s what upsets me.
Click to expand...
Click to expand...
"My objections to the global warming propaganda are not so much over the technical facts, about which I do not know much, but it’s rather against the way those people behave and the kind of intolerance to criticism that a lot of them have."
Thanks for that.
 
Malcolm Kirkpatrick said:
"My objections to the global warming propaganda are not so much over the technical facts, about which I do not know much, but it’s rather against the way those people behave and the kind of intolerance to criticism that a lot of them have."
Thanks for that.
Click to expand...

Let's hilite the part that shows your lie instead.
 
Malcolm Kirkpatrick said:
"My objections to the global warming propaganda are not so much over the technical facts, about which I do not know much, but it’s rather against the way those people behave and the kind of intolerance to criticism that a lot of them have."
Thanks for that.
Click to expand...

Malcolm, I'd say that it's not so much an intolerance for criticism, though it might come across that way to someone like yourself, as much as frustration with the professional dissemblers who are arguing for inaction in the face of a mountain of scientific evidence that shows we are making disastrous changes to our fragile little ecosphere.
 
Malcolm Kirkpatrick said:
jimbob said:
If your contention
Malcolm Kirkpatrick said:
I'm still trying to understand how the surface temperature can depend on anything other than solar output and the radius of the Earth's orbit.
Click to expand...
Is correct, then the surface temperature will be the same in both situations.

The wooden dowels and lack of sides allows free movement of air in both situations.
Click to expand...
What "contention"? How does "I'm still trying to understand" imply any conclusion whatsoever? I already said that observed temperature does NOT depend on solar output and distance alone; consider the day/night variation and the sea level to high altitude variation.
Still, this thought experiment, and lomiller's thought experiment (adding a continuous heat source to an insulated thermos flask) make a welcome departure from relentless (unmoderated) ad hominem. Thanks.
Click to expand...


Maybe I was being harsh, but I thought that you were just using a rhetorical trick when you said that you were "still trying to understand how the surface temperature can depend on anything other than solar output and the radius of the Earth's orbit.".

I was pointing out that a single sheet of glass can demonstrate the greenhouse effect, showing that surface temperature can also depend on the greenhouse effect. There is no additional heat source, just some additional reflection of longer wavelength radiation.

Similarly, the Moon orbits the Earth, so it is on average, the same distance from the Sun as the Earth. The Moon's average temperature, according to this website (top google hit) is about -23°C (-9°F).

The difference between this and the Earth's average temperature of about 15°C is due to the greenhouse effect.

Do these help you understand that if you are talking about average temperatures, the greenhouse effect can not be ignored?

At its simplest, the atmosphere is more transparent to visible light than to IR radiation. A lot of the visible light that hits the Earth is absorbed by the surface, which warms up, and thus re-radiates it as IR radiation. A proportion of this IR radiation is blocked by the greenhouse effect, warming the lower atmosphere.

The greenhouse effect works because of different transparencies to light at different wavelengths.
 
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