## Physics

One of the nice things about physics (well, I like it) is that you can often quantify things by making basic back-of-the-envelope calculations. Maybe a classic example of this is David MacKay’s book about renewable energy called Sustainable energy – without the hot air. It’s a masterclass in how to use simplifying assumptions and basic physics to try and understand various physical processes.

Another example might be the standard Trenberth-like energy flux diagrams. It’s a nice simple illustration that tells us quite a lot about the basic greenhouse effect. If we consider the surface, we know that it receives something like 160Wm-2 from the Sun and has an average temperature of around 288K. Given this temperature, we know it must be radiating around 390Wm-2. We also know that it must lose some energy via non-radiative processes (thermals and evaporation); maybe another 100Wm-2. Hence it is losing – on average – a bit less than 500 Wm-2, but only receiving – on average – about 160Wm-2 from the Sun.

We also know that although surface temperatures can vary (day/night, seasons,…), if we average across the whole globe and over a long enough time interval, it is pretty steady (well, until we started adding GHGs to the atmosphere, that is). This tells us that it must – on average – be receiving as much energy as it loses. Since it is only receiving about 160W-2 from the Sun, it must be receiving – on average – about another 330Wm-2 from somewhere else. This is essentially the greenhouse effect; radiatively active gases in the atmosphere block outgoing long-wavelength radiation, returning some energy to the surface, and causing the surface to warm up to a higher temperature than would be the case were there no such gases in the atmosphere (or, no atmosphere).

We also know that the planet as a whole is in approximate thermal equilibrium (well, again, before we started adding GHGs to the atmosphere) and that we absorb – on average – 240Wm-2 from the Sun. Therefore, we must be ultimately radiating 240Wm-2 back into space. Since it is the atmosphere that is blocking energy from being radiated directly from the surface to space, one way to think of this is that there is some effective radiating layer in the atmosphere from which we lose as much energy into space (240Wm-2) as we gain from the Sun. However, as illustrated by the Trenberth energy flux diagram, it’s not quite that simple; some does come directly from the surface and some from within the atmosphere. We also know that – in reality – more complex physical processes (such as convection and evaporation) play an important role in setting temperature gradients in the atmosphere. However, we can still get a good idea of what’s happening by considering these fairly simple illustrations and calculations.

We can also use this to understand what will happen if we add more greenhouse gases; it makes the atmosphere more opaque to outgoing radiation and raises the effective radiative layer to a higher altitude. This causes temperatures below this layer to increase so that the amount of energy being radiated back into space once again matches the amount of energy being received from the Sun. It is simply an enhanced greenhouse effect.

The above is actually a rather lengthy and convoluted way to introduce something I encountered recently. I came across a blog post that critiques Peter Ward’s ozone depletion theory. Peter Ward’s basic idea is that CO2-driven warming is wrong and that what is causing global warming is the depletion of ozone. His basic idea (which is wrong) is that ozone absorbs ultra-violet (UV) radiation, that there is much more energy in the UV than the infrared (IR), and therefore that the warming is driven by changes in the UV flux driven by changes in ozone. His basic error is that even though a UV photon has much more energy than an IR photon, this does not mean that there is much more energy in the UV than in the IR (you also need to account for the number of photons in each wavelength band)

What I found interesting is that Peter Ward made an appearance in the comments and we had a rather lengthy exchange of views. It was quite a pleasant exchange and only became somewhat tetchy towards the end. However, Peter Ward was completely unwilling to quantify his alternative theory and claimed that the standard methods for determining energy fluxes (as in the Trenberth-like energy flux diagram) are simply wrong – apparently because the energy of a photon is $h \nu$ (which he – incorrectly – kept claiming was the energy per square metre).

Although a little frustrating, I found this discussion quite fascinating. Someone is proposing an alternative to a well accepted theory, but won’t quantify their alternative and suggests that a lot of very basic physics is simply wrong; physics that has been extremely successful for a very long time. This is also physics that virtually every university in the world teaches its undergraduates and that has been used extensively in the development of advanced technologies that many of us use every day; are we just getting it right by chance?

To me, if you’re going to suggest an alternative to something that is well accepted, you have to be willing to actually show how it works quantitatively; you can’t just hand wave. This is especially true if your alternative requires that some very basic things, that are accepted by virtually everyone else, are fundamentally wrong. If you can’t – or won’t – quantify your alternative, then the chances of you being correct is pretty small. If your alternative idea also requires that well-accepted ideas that can quantitively match what we observe/measure are wrong, then the chances of you being correct becomes negligibly small. Given this, the conclusion of the post where I encountered Peter Ward’s ideas is almost certainly correct

his theory is garbage.

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### 99 Responses to Physics

1. The interesting thing about Peter Ward’s reluctance to quantify his ozone warming theory, is that it’s not that hard to throw some numbers out. I had a look at a Solar spectrum, and – at the Earth Sun distance – the solar flux in the UV seems to be around 100Wm-2. If you take into account that the Earth is spherical, this means that the UV contributes about 25Wm-2 to solar insolation. We’ve warming by about 1K and still have a planetary energy imbalance of 0.6Wm-2. Given a Planck response of 3.2Wm-2K-1, this means that the radiatively influence of whatever has caused the warming is around 4Wm-2. If you want this to be associated primarily with UV, then this would seem to suggest a massive change in the fraction of the UV that is reflected or absorbed by ozone in the stratosphere. Seems completely unrealistic. I should add that these are just rough numbers; others might have more accurate values.

2. Actually, to avoid confusion, I wrote this post as though were considering a system in equilibrium where all the fluxes balance. Technically, the Trenberth diagram in the figure is meant to be representative of the system about now; after we’ve increased atmospheric CO2 by about 40%, producing a planetary energy imbalance. Hence, both the TOA and surface fluxes in the diagram are not quite in balance, because of the enhanced greenhouse effect driven by our emissions. It will clearly tend back towards equilibrium as we warm, and had probably been in quasi-equilibrium for a few thousand years, prior to us starting to emit CO2.

3. Dikran Marsupial says:

Another example would be arguments about cycles in climate, but no matter how good the correlation may be, it isn’t going to convince without a plausible physical mechanism that can explain the strength of the observed effect (and preferably show why the other known forcings do not affect climate).

4. Dikran,
Indeed, and that is especially true given that we know that there are variations in climate that can be driven by variations in other factors (like the Sun). However, as I think you’ve pointed out with respect to atmospheric CO2, finding short-term variations in climate that match, for example, short-term solar variations, does not mean that the Sun is the major driver of long-term warming.

5. I haven’t read the Ward post, but shouldn’t one calculate with the UV flux at the surface rather than the Top Of Atmosphere UV flux from the sun? I hope for my poor skin that the UV flux at the surface is a lot, a lot smaller than 25 Wm-2.

6. Victor,
I agree. I was simply pointing out that the maximum UV flux you have is around 25W/m^2 – I think, at least. As you say, the fraction that is actually associated with warming (absorbed by the surface or lower atmosphere) is probably much smaller. Hence, if you want most of the enhanced warming to be due to changes in the UV flux that is absorbed by the surface or in the lower atmosphere, it’s probably – in a relative sense – an enormous, and completely unrealistic, change.

7. Completely unrealistic. If we had 4 Wm-2 UV at the ground, life on land like we know it would no longer exist.

8. Victor,
An interesting point. I hadn’t even considered that.

9. whannah says:

The more I think about Peter Ward’s ideas, the more in awe I am of how cocky he is about them. If any sane person had an earth shattering revelation about basic radiation theory, why wouldn’t they focus on proving the basic principle first? All of his effort is trying to convince people of the dozens of logical steps that might follow if he was correct about step 1, without first arguing for step 1. It’s just so backwards and strange.

10. Walter,
Thanks for the comment (and for others who read this, it’s Walter’s post about Peter Ward’s ozone theory that I was highlighting in this post). I also find it very strange that someone can be so sure of their ideas despite how remarkable it would be if they did turn out to be right and how many things that we regard as basic would need to be wrong. As you say, the obvious step would be to first correct the basics before presenting some final theory that you can’t yet actually use to quantify anything.

11. Willard says:

The imperceptible GW may very well be natural, cyclical, chaotic, where carbon plays a minor role compared to the Sun, cosmic rays, CFCs, ozone depletion, some known unknown (dragons perhaps), or some unknown unknown.

https://contrarianmatrix.wordpress.com/lots-of-theories/

12. Dikran Marsupial says:

@whannah if you think that is cocky, there are plenty out there (Salby, Essenhigh, Humlum, Segalstad etc.) who have argued that the rise in atmospheric CO2 is natural, and not due to fossil fuel use, and the worlds climatologists are fundamentally wrong about the most basic fact imaginable. This is very easily shown to be incorrect, via multiple lines of evidence.

To misparaphrase Einstein: “Two things are infinite: the universe and human hubris; and I’m not sure about the universe!” ?

13. Jim Hunt says:

Hopefully this is not too far off topic, since you’re touching on my “day job” for a change. Is there a physicist (or maybe even an engineer!) in the the house with any bright ideas for SEWTHA 2.0? For some initial thoughts from the Twittosphere see:

http://www.V2G.co.uk/2016/02/what-should-be-in-sewtha-2-0/

Getting back to my moonlighting, does anyone here have any words of wisdom to impart to a “skeptical” fellow who patronises the Halley Professor of Physics at the University of Oxford thusly:

http://GreatWhiteCon.info/2016/04/claim-arctic-sea-ice-holds-firm/#comment-214191

A very interesting theory. A lot more information needs to be gathered, and now that we are developing the technology to gather the data, things will get more interesting.

14. Getting back to my moonlighting, does anyone here have any words of wisdom to impart to a “skeptical” fellow who patronises the Halley Professor of Physics at the University of Oxford thusly:

No, not really. I’ve tried imparting what I thought were words of wisdom (others might disagree) to that “skeptical” fellow. It didn’t have any impact.

15. Jim Hunt says:

I’ve tried imparting what I thought were words of wisdom (others might disagree) to that “skeptical” fellow.

Was that at the Bishop’s Palace Anders?

16. Jim,
Yes.

17. BBD says:

Jim

ATTP is right. RR is not susceptible to reason. See eg. this painful thread on ocean acidification.

18. Jim,
Actually, this comment from Richard Telford, might seem appropriate. In particular,

Demanding decades more data before you will even contemplate that there might be a problem is a classic denier strategy.

19. Jim Hunt says:

Thanks for the info BBD & Anders,

In which case perhaps we’ll see if the “Capybara” is susceptible to surrealism instead?

20. Bizarre sort of error to make. You have to be fairly knowledgeable about science to know that E = H*nu means UV photons are more energetic than visible or IR. But, by that time, you’d also be knowledgeable enough to know Planck’s law and integrate it over IR and UV ranges to see that UV is ca. 10% of the solar output and IR is ca. 50%. (Solar Tb being ~5760 K).

Following a train of reasoning wherever it may lead is not an easy thing. Ugly facts keep slaying our beautiful theories.

21. Robert,
Indeed, that’s what I find confusing. If you know enough to know that $E = h \nu$, surely you also know enough to – as you say – know that to determine the energy in the different bands you need to integrate over the different ranges. I did try to point this out. It didn’t work.

22. Willard says:

> If you know enough to know that E = h \nu, surely you also know enough to – as you say – know that to determine the energy in the different bands you need to integrate over the different ranges.

I don’t see why:

In a recent experiment of his design, British sociologist Harry Collins asked a scientist who specializes in gravitational waves to answer seven questions about the physics of these waves. Collins, who has made an amateur study of this field for more than 30 years but has never actually practiced it, also answered the questions himself. Then he submitted both sets of answers to a panel of judges who are themselves gravitational-wave researchers. The judges couldn’t tell the impostor from one of their own. Collins argues that he is therefore as qualified as anyone to discuss this field, even though he can’t conduct experiments in it.

http://www.slate.com/articles/health_and_science/science/2006/10/the_amateurs_revenge.html

I think you mean if Peter really knew what he was talking about.

23. I think you mean if Peter really knew what he was talking about.

Yes, probably. Fascinating article about Harry Collins. I’m not quite sure what it indicates, though. He did, apparently, spend 30 years studying it at an amateur level. Doesn’t really seem to refute the idea that a reasonable depth of knowledge requires some amount of effort.

24. BBD says:

Doesn’t really seem to refute the idea that a reasonable depth of knowledge requires some amount of effort.

Which brings us back to B. B. King and the other guy.

25. Willard says:

> Doesn’t really seem to refute the idea that a reasonable depth of knowledge requires some amount of effort.

I think it takes some effort to reach Peter’s level of sophisticated obfuscation. It takes time and dedication. Peter probably read quite a lot, perhaps even more than actual climate scientists. However, it’s quite clear he’s trying to portray himself as having the expertise to contribute without having even reached interactional expertise. This is not a problem for the contrarian audience he may be targetting, which is built on a narrative, with talking points, memes, and so forth.

I note that whannah had to work quite a bit to switch from his “talking about” mode, where tone can be harsh, to “talking to,” where your interlocutor can raise concerns about your tone. He did surprisingly well. Better at the very least than this other guy:

26. Magma says:

that there is much more energy in the UV than the infrared (IR)…
because the energy of a photon is h \nu (which he – incorrectly – kept claiming was the energy per square metre)…

If someone is unwilling to do the basics of understanding the Planck radiation formula and working through the steps to calculate the power per wavelength interval, or at the other end not bother to find out that ground level UV and IR flux are routinely measured at many observatories, then I don’t know what to say. And all that careful work on his ozone depletion theory website, the plots, graphs and text… all wasted thanks to some basic misunderstandings that can be a hazard of the self-taught.

Anyway, enough time wasted on cranks and their faulty ideas. My groundbreaking paper proving that birds are actually feathered insects isn’t going to write itself.

“I think it takes some effort to reach Peter’s level of sophisticated obfuscation.”

Indeed, and the growing number of such expert crackpots at large on the internet is why I, a layman, abandoned climateball and left it to scientists to hold up the side. My thanks to Walter and our host for this “result.”

28. John Mashey says:

He and his friend had a booth at AGU2015 (i.e., spent the money), and I stopped by and picked up brochures, but did not talk to them. One of the brochures stated:

“There has been a fundamental misunderstanding in physics about what radiant energy is and how it should be calculated. Natural philosophers and scientists have debated for 2400 years whether light travels as waves or as particles. New observations show that light and other forms of electromagnetic radiation travel simply as frequency, in a manner similar to the signal from your cellphone or a radio station, and that the thermal energy involved is simply equal to frequency times a constant, representing the energy of the atomic oscillators which are the sources of radiation. It turns out that the energy of ultraviolet B radiation is actually 48 times greater -48 times “hotter”- than the energy of infrared radiation, confirming common experience. There simply is not enough energy involved with greenhouse gases for them to play a significant role in global warming.”

So there.

29. 160,390,100 W/m2. If you quote some numbers, you should say how the quantities are measured and how large the uncertainty of the measurement is. Today it is cloudy.

30. Paul,
This is a blog post, not a peer-reviewed paper. Also, that it is cloudy today would be rather irrelevent if we’re considering quantities averaged over a sufficiently long time interval so that short timescale variations average out.

However, since you asked so nicely (?) here’s a more recent figure from Stephens et al. (2012) which also includes uncertainties

31. Andrew dodds says:

Magma –

That often seem the blind spot of cranks. Assuming that their pet theory is completely restricted to their hobby horse area with no wider effects. After all, the sun must presumably emit traces of far-UV to soft X rays.. So if we ignore intensity, we must all be fried.

More often in global warming areas it’s a case of ‘proving’ that sensitivity is very low and hence climate can never change. Which requires ignoring the whole geological record.

32. Adam R. said on April 10, 2016 at 5:30 am,

“…the growing number of such expert crackpots at large on the internet is why I, a layman, abandoned climateball and left it to scientists to hold up the side.”

This phrase “expert crackpot” or “expert crank” is one we should all remember. It’s a good way of characterizing a phenomenon about which the educational experts need to teach and have failed to successfully teach to the general population. This failure is evidenced especially here in the US by how large a percentage of the population rejects professional science in so many areas of science.

These educational experts should make it a priority to teach the general public to accept the professional scientific literature (defined to be the reputable, professionally refereed science journals and the reputable science textbooks and monographs all taken in their ongoing aggregate) to be the best humanity has at any given time as to what the truth really is about this physical universe. This includes teaching the general public that since they simply will not have the tools to refute what these expert crackpots say, they the general public should essentially not even listen to these expert cranks. (Sure, the general public can learn some basic logic, including some fallacies, formal and informal, but that would not be enough to refute these expert crackpots on many points. The general public ultimately needs to learn to trust professional science along the lines of the earlier definition.)

33. Marco says:

“New observations show that light and other forms of electromagnetic radiation travel simply as frequency, in a manner similar to the signal from your cellphone or a radio station, and that the thermal energy involved is simply equal to frequency times a constant, representing the energy of the atomic oscillators which are the sources of radiation.”

Errr…uhm…[scratches head]. New observations? This just sounds (to me, at least) like a poorly-worded convolution of the wave-particle duality, not anything new. Well, apart from the last part of the sentence, but that part doesn’t make much sense. Also, it is almost as if Ward suggests the signal from cellphones or a radio station is not a form of electromagnetic radiation.

34. angech says:

“I had a look at a Solar spectrum, and – at the Earth Sun distance – the solar flux in the UV seems to be around 100Wm-2. If you take into account that the Earth is spherical, this means that the UV contributes about 25Wm-2 to solar insolation.”
I am not sure on this.
Should the incoming figure of 341.3 Wm-2 from the Sun be an average applied to the whole of the earth taking into account it’s sphericity and the fact that there is a half that is getting no sun at all?
Wiki “The total amount of energy received per second at the top of Earth’s atmosphere (TOA) is measured in watts and is given by the solar constant times the cross-sectional area of the Earth. Because the surface of a sphere is four times the cross-sectional area of a sphere, the average TOA flux is one quarter of the solar constant and so is approximately 340 W/m²”
Obviously I am missing something.
If I am right the total amount of energy at midday in the square meter[s] directly under the sun are a lot, lot higher than 341.3 Wm-2 [wild guess 1360 WM-2].
The 100 Wm-2 of UV incoming would then be a much smaller amount [13.6 times smaller] of the solar flux.
as Victor Venema says:
” I hope for my poor skin that the UV flux at the surface is a lot, a lot smaller than 25 Wm-2.”
Do we know what the actual daytime energy is eg just double the total so 481.6 average?

35. angech says:

I had an interesting discussion with Neil King at Lucia’s on the temperature of the earth.
The Earth and the moon should be at the same temp with no atmosphere and similar albedo.
the moon is actually tar black, lower albedo than earth so should be at a higher average temperature. That the layer of air and water at the earth surface is hotter on average than the moon is a function of GHG.
Moon Earth Ratio (Moon/Earth)
Mass (1024 kg) 0.07346 5.9724 0.0123
Solar irradiance (W/m2) 1361.0 1361.0 1.000
Black-body temperature (K) 270.4 254.0 1.065
From space the earth appears colder as a body though it’s skin layer is warmer.
He won on the topic of heat loss from a spherical body.

36. angech,
The 100Wm-2 referred to the UV portion of the spectrum only. Across all wavebands it is 1360Wm-2. I also did divide by 4 to take into account the Earth’s geometry. If you divide 1360 by 4, you get 340Wm-2 which is the Solar insolation. UV contributes about (according to what I looked up) maybe 25Wm-2.

Should the incoming figure of 341.3 Wm-2 from the Sun be an average applied to the whole of the earth taking into account it’s sphericity and the fact that there is a half that is getting no sun at all?

It already has been. Solar flux at 1AU is 1360 Wm-2.

37. angech,
I saw some of the discussion on Lucia’s with Neal. Neal’s physics is pretty solid.

38. izen says:

@-“From space the earth appears colder as a body though it’s skin layer is warmer.”

As with Venus.
I wonder how the ‘UV theory’ applies to explain Venusian climate…

39. izen says:

@-KeefeAndAmanda
“These educational experts should make it a priority to teach the general public to accept the professional scientific literature … This includes teaching the general public that since they simply will not have the tools to refute what these expert crackpots say, they the general public should essentially not even listen to these expert cranks.”

I am unconvinced that it is possible to teach people to be less sceptical of mainstream sources of authority. I suspect that even if it was possible it may be ethically dubious.
It sounds like the sort of thing that religions and churches do warning against heretics. Even claiming their authority is absolute fails to prevent apostasy.

Acceptance of establishment authority derives from the level of engagement and trust that an individual invests in that society. Their relationship to established authority and communal governance shapes their acceptance without analysis, of the mainstream position on science. The trust placed in mainstream science is an emergent property of the social engagement, not a separately educable feature.

It is unfortunately possible to undermine the degree of trust and therefore unquestioned acceptance of mainstream knowledge by attacking the integrity and utility of the mainstream governance system. Because mainstream science is closely allied with that establishment position the distrust of government carries over into distrust of science.

In the US there has been a political movement (astroturfed) to undermine the worth of governance, specifically to remove taxes and regulations which in turn limits welfare and other government spending, including on science research. It is odd to see commercial enterprises seeking to destabilise the authority of governance in the interests of enhanced profitability when that profitability only makes sense in a stable society.
Although if you can move all the profits to Panama, or Delaware, I don’t suppose it matters.

40. Following izen — from space, Venus is also colder than the Earth.

41. Willard says:

> Indeed, and the growing number of such expert crackpots at large on the internet is why I, a layman, abandoned climateball and left it to scientists to hold up the side.

It’s hard to declare leaving ClimateBall without playing ClimateBall.

Dealing with expert crackpots in an expert manner is one of most expedient ways to improve one’s expertise. Refuting crap is not that easy, and understanding where the misunderstanding occurs is even less easy. An expert’s background may not prepare well for that kind of thing. Besides, one has to resist the urge to flame instead.

We’re on the Internet – experts might as well get used to be thankful for all the concerns.

42. Joshua says:

K & A –

==> These educational experts should make it a priority to teach the general public to accept the professional scientific literature…

How do you define “educational expert?”

Do have ideas for educational approach do you suggest that be done? Are you thinking of particular that your goal is realistically achievable?

IMO, your statement suggests a didactic, top-down vision of education that is inconsistent with the evidence on effective education, and with the likely pedagogical process that educational experts might recommend.

@Willard
“It’s hard to declare leaving ClimateBall without playing ClimateBall.”

Who says I didn’t play? I’ve played the game since usenet days.
.
.
“Dealing with expert crackpots in an expert manner is one of most expedient ways to improve one’s expertise.”

Well, yeah, thanks to playing ClimateBall I’ve certainly (perforce) learned a great deal about AGW, starting from next to nothing. However, I was never going to reach the level of understanding necessary to demolish effectively someone who is educated to PhD level in physics. I have a career in a field only distantly related to the subject. It would require considerable reading and researching on my part trying to keep up with Ward’s arcane Gish gallop, while two scientists had the ammunition at hand to destroy him quickly with a couple of well placed shots. (Which expanded my understanding, BTW. Ta very much, lads.)

On unrelated forums, I occasionally encounter the old wheezers like, “In the ’70s the consensus was cooling!” and I’ll debunk those, but Premier League ClimateBall these days gets beyond my effective arguing reach in a hurry, and I simply don’t have the chops for it when expert cranks like Peter Ward appear.
.
.
“We’re on the Internet – experts might as well get used to be thankful for all the concerns.”

??

44. > Who says I didn’t play?

You, here:

Indeed, and the growing number of such expert crackpots at large on the internet is why I, a layman, abandoned climateball and left it to scientists to hold up the side.

Perhaps I misunderstood.

***

> Premier League ClimateBall these days gets beyond my effective arguing reach in a hurry […]

Indeed, and this may explain why AT’s got so much concerns raised against him at first.

***

> ??

Read the comment thread at whannah’s or the story behind the tweet I cited earlier, or this:

45. Jim Hunt says:

@Adam – I never quite got around to writing up my PhD (engineering, not physics). Nonetheless I find myself actually quite enjoying my current match with Willard (Watts, not nevaudit):

The Awful Terrible Horrible Arctic Sea Ice Crisis

One feels compelled to ask why Willis’s global average temperature graph neglects to mention 2015 when he implies that it does?

What division would you estimate that we’re playing in?

46. Ken Fabian says:

Izen – “I am unconvinced that it is possible to teach people to be less sceptical of mainstream sources of authority. I suspect that even if it was possible it may be ethically dubious.”

The ‘ordinary’ person’ has some kind of right to believe and promulgate whatever beliefs they like however there are well established legal precedents for those holding positions of trust and responsibility to take expert advice seriously – where that advice warns of harmful and damaging consequences arising from decisions being made. Which is one reason why the credentialed maverick experts (rather than expert crackpots) are so highly valued by those seeking ways to avoid such advice whilst avoiding legal consequences like charges of criminal negligence; the broader spreading of doubt, denial and delay to the general public is important too, if widespread enough it also allows a kind of ‘reasonable person’ defence for ignoring the mainstream expert advice.

Of course there isn’t a well established precedent specific to mainstream climate expert advice like there is for, say, engineering or medical advice even though the essential precedent is there. The time scales, where full consequences are long delayed, beyond a single human lifespan, are a big challenge to common law legal systems as well. And the benefits vs harms issue complicates things when we have become so widely dependent upon fossil fuel burning that rapid cessation itself will cause harm, and more immediately than the long term use.

I think responsibility avoidance by those who can be held to have such responsibility underpins much of the high level support from commerce and industry and political organisations – much of the fractious mess we have for climate/energy politics is a consequence of that support; tank think, PR, advertising, lobbying, judicious donating are all established tools for challenged industries to protect themselves. The expert crackpots could not have the reach they do but for those activities, which include the legitimising of unreasonable and inappropriate scepticism of (specific targeted) authorities.

Yeah, Jim, I saw that. The naked cowardice at Anthony’s lost it’s last fig leaf long ago, didn’t it? I don’t think Willis can excuse himself with ignorance—or even stupidity.

And from what I’ve seen of you, you seem quite fit for the game. Definitely Premier League talent. (Jeez, this metaphor is getting tatty!)

48. angech says:

Robert Grumbine says: April 10, 2016 at 1:28 pm
“Following izen — from space, Venus is also colder than the Earth.”
Not sure how this works Robert.
Venus is closer to the sun so must get more energy in hence must out more energy out [depending on albedo of course]. Off the top of my head I would feel Venus should appear a lot warmer than earth from space.

49. angech says:

Robert Grumbine
You are correct , sir.
The reason though would be the much higher Venusian albedo Venus Earth Ratio (Venus/Earth)
Bond albedo 0.90 0.306 2.94
Visual geometric albedo 0.67 0.367 1.83
Solar irradiance (W/m2) 2601.3 1361.0 1.911
Black-body temperature (K) 184.0 254.0 0.724
The little energy that makes it in sure makes it hot. in the atmosphere
Average temperature: 737 K (464 C)
Major: 96.5% Carbon Dioxide (CO2), 3.5% Nitrogen (N2)
No oxygen of note

50. Jim Hunt says:

@Adam – Thank you for your kind words. Actually the opposition would disgrace a Sunday morning pub league team still carrying a bellyful of beer from the night before.

Meanwhile commenter Kasia has concocted a suitably surreal put down for the “Repetitive Rodent”:

http://GreatWhiteCon.info/2016/04/claim-arctic-sea-ice-holds-firm/#comment-214200

Snow White, please stop wasting your time here, go and spend more time with your Prince Charming, he is longing for some good sex.

51. Jim Hunt says:

http://itila.blogspot.co.uk/2016/04/perhaps-my-last-post-well-see.html

There’s lots I could write, but the way I’d like to stop is by pointing you to the writings of someone else. Max Edwards wrote a piece for the Guardian about his own cancer, and much of what he writes resonates for me. He was a remarkably eloquent writer.

52. BBD says:

53. Angech says:
April 11, 2016 at 7:58 am

“Major: 96.5% Carbon Dioxide (CO2), 3.5% Nitrogen (N2)
No oxygen of note (Venus)”

Thanks Angech. But you forgot to discuss the importance of water in the atmosphere for establishing the mean surface temperature. In short: Venus is a “CO2” planet, the earth is a “water” planet. Today it is cloudy in southern Germany.

54. Jim Hunt says:

@BBD – Neither did I, until I fired up Twitter yesterday. The latest news about Prof. David MacKay’s health can be seen here:

https://www.justgiving.com/davidjcmackay

David is still alive and stable in Addenbrookes hospital, as of Tuesday 12th April. We are setting up this JustGiving page in case anyone would like to make gifts to the Arthur Rank Hospice Charity

55. Have just heard that David MacKay died today. My condolences to his family and friends.

56. Dikran Marsupial says:

That is very sad news indeed.

57. Jim Hunt says:

My own modest remembrance of Sir David MacKay:

http://forum.arctic-sea-ice.net/index.php?topic=1522

A rather more comprehensive one from Athene Donald:

http://occamstypewriter.org/athenedonald/2016/04/16/rip-sir-david-mackay/

He was an extraordinary man who contributed so much to physics and wider societal issues during his tragically short life.

Somehow his character pervaded the world around him and made us all more aware of the importance of finding ways to communicate beyond our own communities.

58. The revised Trenberth energy flow diagram (from Stephens et al.2012) is strange in that it shows more energy coming from the atmosphere than from the sun. How is that possible?

59. John,
You need to consider all the fluxes. The amount of energy received by the atmosphere matches the amount of energy it radiates.

60. We know the radiation type from the atmosphere is IR. But what is the radiation type coming from the sun?

61. John,
It’s very close to a blackbody with a temperature of 5800 K, so it peaks in the visible.

62. Thanks for the graph. I can understand how sun’s intense radiation heats the earth’s surface, because the sun is hotter than the earth. As a meteorologist, I know that the earth’s surface heats the air. But the air is not hotter than the earth, so I can’t see how the air can heat the earth like the sun does.

63. Marco says:

John, it is not the air heating the earth so much, but rather the greenhouse gases in the air reducing radiative losses in some parts of the energy spectrum from the atmosphere to space, necessitating a warming of the earth’s atmosphere, such that the other parts of the energy spectrum increase to match incoming energy.

An example from another field: as you may know, lightbulbs have filaments that act like blackbody emitters. The energy input is from the current running the filament. Unfortunately, a lot of that energy is ‘lost’ in the form of IR radiation. We generally don’t use lamps to heat our house, we use them to see, so we are only interested in the visible light, the rest is energy wastage. Engineers have found a way to reduce this energy wastage: add an IR coating to the inside of the lightbulb. It reflects the IR radiation back, but lets the visible light through. But then less energy comes out than is being put in, meaning the internal system will heat up – indeed, (further) heating of the filament can be measured when you put an IR coating on the inside of the bulb. That’s no good, however, as the filaments are generally already run to optimal temperature to get the best light output (in terms of peak wavelength in the visible light). Solution is to reduce the current, which then ‘cools’ the filament to the desired temperature.

The IR coating in this lamp is like the addition of greenhouse gases to the atmosphere. The main difference is that we cannot just reduce the solar input in the same way we adjust the current going through a lamp…

64. John,
Marco’s already explained this nicely. It’s not that the air heats the surface, it’s that the greenhouse gases in the atmosphere impede the flow of energy from the surface to space. This causes the surface, and lower atmosphere, to warm until the amount of energy radiated into space from the top of the atmosphere matches the amount of energy we get from the Sun. Something to stress is that the energy all comes from the Sun, so there is no violation of any thermodynamic law.

Consider the following. You have a heating system in your house. If you turn it on, it will heat the inside up until it reaches some kind of equilibrium where the amount of energy flowing through the walls and windows matches the amount of energy being generated by your heating system. If you now add more insulation (or change your windows) then this will slow the flow of energy to the outside and cause the inside to warm up even more. This new insulation hasn’t somehow generated new energy, it’s simply changed the energy flow.

65. If the air is like insulation (which I agree) which slows earth’s coooling, then why does the Trenberth diagram (2008) show a downward radiation leg of 333 atmospheric flux units being absorbed by the earth? This appears to be a violation of the 2nd Law of Thermodynamics.

66. JCH says:

Who knows? Maybe because the earth absorbs SW photons and then emits them as LW to the atmosphere where the are absorbed and emitted as LW in lots of direction, including back to earth, where the are reabsorbed, and then reemitted, and so on until roughly the original SW amount, in the form of LW, is emitted to space. All of which takes a little longer with each new ACO2 molecule.

Or, maybe a whole bunch of PhD atmospheric physicists violated the 2nd law. Happens all the time.

67. John,

why does the Trenberth diagram (2008) show a downward radiation leg of 333 atmospheric flux units being absorbed by the earth? This appears to be a violation of the 2nd Law of Thermodynamics.

That’s how the energy fluxes at the surface are balanced. Some directly from the Sun, and some returned from the atmosphere. It doesn’t violate the 2nd Law of thermodynamics because this says that there can’t be a *net* flow of energy from a cold body to a hot body. It doesn’t say that no energy can flow from a cold body to a hot body (more energy must go from hot to cold, than from cold to hot, but there can still be energy flow from cold to hot). If you look at the Figure, the surface transmits about 471 W/m^2 to the atmosphere (374 + 80 + 17) and receives 333 from the atmosphere. Hence, the net transfer of energy is from the surface to the atmosphere, but the atmosphere still returns some energy to the surface.

68. The “clue”:

how sun’s intense radiation heats the earth’s surface, because the sun is hotter than the earth

These conversations are often lost early in the concept of radiative transfer and an insistence that the flow is (only) from hotter to cooler. But why then, for instance, can we measure an incoming IR flux from the moon, etc.

69. For such a straightforward law, it is surprisingly often misunderstood by those that invoke it. There is a nice post about this at science of doom

https://scienceofdoom.com/2010/10/07/amazing-things-we-find-in-textbooks-the-real-second-law-of-thermodynamics/

70. If you lie under a blanket, both the blanket and the air underneath it is coover than your body, so how is it that lying under a blanket warms yout up – evidently it does.

71. When you say, “… there can’t be a *net* flow of energy from a cold body to a hot body,” infers the 2nd Law is wrong. This infers water can flow uphill. Are you actually saying heat can flow from cold to hot?

72. Ben McMillan says:

The thing I am always wondering about people who are confused about radiative transfer, is what do they think happens to the photons that the atmosphere emits that are going downwards?

I mean, does the surface ask to see their passports, and its all like, “nu-up, you come from a cold place, and I’m warmer, so I’ve decided not to absorb you”?

73. JCH says:

Watch a beach. It flows uphill, and then it flows downhill.

74. verytallguy says:

“When you say, “… there can’t be a *net* flow of energy from a cold body to a hot body,” infers the 2nd Law is wrong”

Nope.

There is a constant radiative flux from all bodies. Some of this must be absorbed by hotter bodies. The 2nd law remains intact.

Top think of it a different way, photons have no memory.

75. John heat doesn’t flow in the sense that water flows, it is a metaphor – science realised that when caloric theory was dropped. Read the Science of Doom article that I linked to, it explains what the second law actually says quite clearly, using thermodynamics textbooks to demonstrate the validity of the explanation.

76. John,

When you say, “… there can’t be a *net* flow of energy from a cold body to a hot body,” infers the 2nd Law is wrong. This infers water can flow uphill. Are you actually saying heat can flow from cold to hot?

Others have already covered this, but energy flow isn’t like water flowing downhill. Everything basically emits energy. Hence, there could be energy from a cold body that is absorbed by a hotter body. However, there can’t be a *net* flow of energy from a cold body to a hot body. In other words, there can’t be energy flows between a hot body and a cold body that makes the hotter body warmer.

Consider the point being made by Ben. The atmosphere absorbs energy from the surface and then essentially radiates this energy back out again. However, there is no mechanism to ensure that this energy is only radiated away from the surface. So, what happens to the energy that is radiated back down towards the surface? If it hits the surface, it will be absorbed. However, again, the surface transfers more energy to the atmosphere than is transferred from the atmosphere back down to the surface. Therefore, there is no violation of the laws of thermodynamics.

77. I order that we have a specific, common reference point, please provide a definition of the 2nd Law from a reputable or academic source.

78. John,

79. Thanks for the link, but I am only interested in the Law as stated by established science. Please provide a definition of the 2nd Law from a reputable or academic source.

80. John,
You may have to tell me what you’d regard as a reputable source. I have a bunch of physics textbooks in my office, but I’m currently at home. You can presumably Google as well as I can.

81. There is no rush. I intend to be here a long time. This is important so a methodical approach is best. While Google can be a source of many sources, I am only interested what “you” believe is the best definition of the 2nd Law. If you truly believe energy can flow from cold to hot, then it should be easy to find a supporting, academically accepted definition.

82. John,
Maybe we should clarify quite what we’re saying. The 2nd Law of thermodynamics says that heat flows from hot to cold. In other words, if you have two reservoirs at different temperatures, the net flow will be from hot to cold (the cold reservoir cannot heat the warm reservoir). However, if these two reservoirs are transferring energy via radiation, then there is nothing in physics that prevents energy radiated from a cold reservoir from being absorbed by a hot reservoir. It clearly can – as the Realclimate post points out, some of the thermal radiation from the Earth must intercept the Sun. However, much more comes from the Sun to the Earth, than from the Earth to the Sun – the net flow is from the Sun to the Earth. Similarly, even though some radiation from the atmosphere hits the surface, the net flow is from the surface to the atmosphere.

Since you seem to dispute this, maybe you can explain what prevents energy radiated from the atmosphere from hitting the surface. How does this work?

83. JCH says:
84. Marco says:

John, I guess this one isn’t reputable enough:
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/seclaw.html
“It is important to note that when it is stated that energy will not spontaneously flow from a cold object to a hot object, that statement is referring to net transfer of energy. Energy can transfer from the cold object to the hot object either by transfer of energetic particles or electromagnetic radiation, but the net transfer will be from the hot object to the cold object in any spontaneous process. “

85. Ben McMillan says:

Well, I for one, like “Landau and Lifshitz, Vol 5”, with its “if a closed system is at some instant in a non-equilibrium state, the most probable consequence at later instants is an increase in the entropy in the system”.

Note that it doesn’t directly say anything about individual energy flows in the system. You can deduce the usual ‘high school textbook’ second law of thermodynamics from that: the entropy formulation makes it clear that it is the change in temperature of objects that matters, which depends only on net (not broken down) energy flows.

It is easy enough to split up an conductive heat flow between two solid bodies into two large parts that nearly cancel. Count the energy flux in vibrations going one way, then the other.

The “Cassandra’s legacy” blog has some nice examples of textbooks explaining this aspect of radiative physics.

86. Maybe John can consider the following. Let’s consider the state prior to our emission of CO2 into the atmosphere when surface temperatures didn’t vary much over a period of centuries. We’re pretty confident that the Sun then wasn’t very different to today and that the albedo of the planet wasn’t very different. Given this, we would have been receiving 240 W/m^2 from the Sun. The surface temperature was about 288K. It’s a blackbody, so would be emitting about 396W/m^2. Hence, it was emitting much more energy than it was receiving from the Sun, but was able to maintain a roughly constant temperature. How is this possible if the surface isn’t able to receive energy from anywhere else?

87. dikranmarsupial says:

” If you truly believe energy can flow from cold to hot, then it should be easy to find a supporting, academically accepted definition.”

If only someone had posted a link to a page with scans of several academic thermodynamics textbooks showing what they have to say on the subject.

This is what Clausius says in the English translation of the second edition of his book says (on page 78)

It is true that by such a process (as we have seen by going through the original cycle in the reverse direction) heat may be carried over from a colder into a hotter body: our principle however declares that simultaneously with this passage of heat from a colder to a hotter body there must either take place an opposite passage of heat from a hotter to a colder body, or else some change or other which has the special property that it is not reversible, except under the condition that it occasions, whether directly or indirectly, such an opposite passage of heat. This simultaneous passage of heat in the opposite direction, or this special change entailing an opposite passage of heat, is then to be treated as a compensation for the passage of heat from the colder to the warmer body; and if we apply this conception we may replace the words “of itself” by “without compensation,” and then enunciate the principle as follows:

“A passage of heat from a colder to a hotter body cannot take place without compensation.”

which couldn’t make it any clearer that energy can flow from a colder to a warmer body if there is a greater flow of energy from warmer to cooler. Which is exactly what we see in the Trenberth diagram.

88. dikranmarsupial says:

If you don’t believe me, you can get a .pdf here. The quote is from the bottom of page 78, which is page 92 of the pdf file.

As Clausius was AFAICS the first to state the second law of thermodynamics, I think we can take that as fairly authoritative ;o)

89. dikranmarsupial says:

How about Max Plank (who knew a thing or two about thermodynamics) and Masius:

A body at 100◦C.emits toward a body at 0◦C.exactly the same amount of radiation as toward an equally large and similarly situated body B at 1000◦C. The fact that the body A is cooled by B and heated by B′ is due entirely to the fact that B is a weaker, B′ a stronger emitter than A.

[source: Planck and Masius, “The Theory of Heat Radiation”, 1914, page 9]

90. Willard says:

> I intend to be here a long time.

I’m afraid you don’t get to decide the amount of room service you receive, John.

91. Your description of heat flow is “your” interpretation of the 2nd Law. As of today, no one has proven cold objects can heat warm objects. If the proof existed, it would be on the front page of the New York Times. Right now it’s only wishful thinking. This fallacy is the same for those who “wish” cold fusion was real. They both violate the 2nd Law.

You have presented extended interpretations of the 2nd Law — but not a formal quote of the actual Law from a reputable source. This is the missing link of your arguments — a starting or common reference point. You can not erect a building without first establishing a sound foundation.

You can ignore the 2nd Law (and the countless combined hours of hard work from Einstein, Plank, Bohr, etc.), or we start at a common agreed upon definition of the 2nd Law. If you wish, I can provide one — just let me know. But I prefer “you” identify this Law since it is you who is trying to apply alternate meaning. In the meantime, I will provide something to contemplate as a clue to understanding the 2nd Law. As you place a hot cup of coffee on an insulated table in a sealed cool room … will the room make the coffee hotter?

92. John,
We’ve probably reached a point of dimishing returns. Noone is saying cold can warm hot (i.e., in a system with a cold object and a hot object, the heat flow will be from hot to cold). Dikran has, however, provided a number of original sources that highlight that energy can still go from cold to hot, but there can’t be a net flow of energy from cold to hot. You could ponder this and – if you wish – you could present your definition of the 2nd Law (although I suspect noone here will disagree with the definition; they might disagree with the interpretation).

93. David B. Benson says:

John Shewchuck, kindly explain how a heat pump causes the cold side to become colder and the warm side to become warmer. As in air conditioners and refrigerators.

94. dikranmarsupial says:

“As of today, no one has proven cold objects can heat warm objects. If the proof existed, it would be on the front page of the New York Times.”

I rather doubt that the New York Times would view the demonstrably fact that blankets warm you (even though both the blanket and the air underneath it is cooler than you are) as being remotely newsworthy.

95. dikranmarsupial says:

“You have presented extended interpretations of the 2nd Law — but not a formal quote of the actual Law from a reputable source.”

Nonsense. I gave formal quotes, including page numbers from Clausius and Max Plank, both of which are *very* reputable sources.

96. Marco says:

I did a bit of Da Googel, and found this:
https://www.villages-news.com/2019/04/15/dont-let-climate-change-hoaxers-seduce-your-common-senses/
Count the ideological dog whistles, note the outright misinformation (lies, even). My prediction: Shewchuk will continue to ignore the answers he gets, because the answers he gets is not what he wants to hear.

97. [#ButGalileo. -W]

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