> John Peter
> Akasofu
> expert climate scientist evaluation who either have already done
> the work or mindlessly reject anything he claims.
Like I said, Google would dearly love to befriend you. You can look this up.
Yes, if Google is part of a global scientific mindless conspiracy, along with every scientist who could follow his math and evaluate the claim, and every journal editor — then you won’t find much support for his ideas.
You have to weigh the possibilities that you consider may be real.
— massive mindless conspiracy of every possible person, or
— big yawn by people who’ve evaluated the ideas
Go with the probabilities.
What do you consider may be possibly real?
You include the massive worldwide conspiracy in your reality?
I don’t endorse the thoughts of the two following people…but these are two of the brightest brains who usually accurately predict trends by about 15-20 years.
World famous thinker/former peer-reviewed scientist James Lovelock says:
“I don’t think we’re yet evolved to the point where we’re clever enough to handle a complex a situation as climate change,” said Lovelock in his first in-depth interview since the theft of the UEA emails last November. “The inertia of humans is so huge that you can’t really do anything meaningful.”
One of the main obstructions to meaningful action is “modern democracy”, he added. “Even the best democracies agree that when a major war approaches, democracy must be put on hold for the time being. I have a feeling that climate change may be an issue as severe as a war. It may be necessary to put democracy on hold for a while.”
Lovelock, 90, believes the world’s best hope is to invest in adaptation measures, such as building sea defences around the cities that are most vulnerable to sea-level rises. He thinks only a catastrophic event would now persuade humanity to take the threat of climate change seriously enough, such as the collapse of a giant glacier in Antarctica, such as the Pine Island glacier, which would immediately push up sea level.
“That would be the sort of event that would change public opinion,” he said. “Or a return of the dust bowl in the mid-west. Another Intergovernmental Panel on Climate Change (IPCC) report won’t be enough. We’ll just argue over it like now.” The IPCC’s 2007 report concluded that there was a 90% chance that greenhouse gas emissions from human activities are causing global warming, but the panel has been criticised over a mistaken claim that all Himalayan glaciers could melt by 2030. http://www.guardian.co.uk/science/2010/mar/29/james-lovelock-climate-change
I know James Hansen has made a similar statement about democracy (storms of my grandchildren).
[Response: No he didn’t, despite what you might have read elsewhere. – gavin]
Ray Ladburysays
John Peter,
Akasofu is a pretty reasonable solar scientist. He is not, however, a climate scientist. He’s been caught in some pretty basic errors (e.g. ignoring SO2 dimming), and he has declined to publish his work in climate science. However, to merely say that “we are recovering from the LIA” without proposing a forcing mechanism isn’t science.
My question to you is this: Why do you give more credence to a solar/aurora physicist on climate science than you do to climate scientists, particularly when the climate scientists have a very well supported and venerable theory that explains their observations and Akasofu is merely asserting a “recovery” and proposing no credible mechanism?
Septic Matthewsays
599, John E. Pearson: The authors of the paper you linked to spend pages and pages on stuff that is completely trivial, showing for example that the product of integrals isn’t equal to the integral of the product, etc.
On the whole, I think I like my characterization better: the authors attempt to quantify the effects of the variations in temperature across regions of the earth. They do so to show that Smith’s rebuttal can’t be precise enough to achieve its stated aim. Applied math is all about approximations, and they conclude that Smith’s simplifications lead to approximations that are too coarse. One of the details of their argument, which they claim Smith overlooked, is a fact of calculus that you claim is taught in high school. That it is taught in high school is not relevant to anything, except possibly to show that Smith’s paper ought not to have been believed by anyone who studied high school calculus.
G&T might be wrong, but Smith’s rebuttal is inadequate to prove them wrong.
597, Completely Fed Up: With a physical model you don’t have to guess.
Even with a physical model (and there isn’t an adequate physical model for the response time) the parameters would still have to be estimated, not guessed. Without a physical model, examining the cross-lagged correlations is a way to estimate the response time. Maybe not real accurate, yet maybe the best available so far. RPB only supplied 13 data points. The cointegrated VAR models might give a better estimate.
John E. Pearsonsays
China Huaneng Group, the nation’s biggest power generator, targets a capacity to produce about 35 percent of its electricity from clean energy by 2020 as the country seeks to cut pollution, President Cao Peixi said.
” but Smith’s rebuttal is inadequate to prove them wrong.”
Please explain why.
Because as far as most of the educated world considers, Smith’s rebuttal is adequate.
“Even with a physical model (and there isn’t an adequate physical model for the response time)”
Says the man who insists there’s a good model of climate in fourier analysis…
I rest my case.
CMsays
Andreas,
> So why is Anthropology excluded and earth sciences included in the IPCC?
Rephrasing. Why does the IPCC discuss climate change a lot in terms of earth sciences and very little in terms of anthropology?
Because it’s obvious how it is an earth science problem, but not quite so obvious where anthropology comes in? Because earth scientists describe their work as having to do with anthropogenic climate change, and anthropologists do not (that was what I suggested)? Because anthropologists compete with other social scientists, like economists, who have pretty sharp elbows when it comes to getting to formulate the basis for policy? I could think of many plausible explanations…
> because the earth sciences control IPCC.
…but that wouldn’t be one of them.
> paleoclimate studies from the earth sciences are largely excluded
> from the IPCC.
The original G&T was so utterly wronger than wronger than wrong that even imprecise work is adequate to illustrate that they were just completely off the tracks of science and logic.
If the 1-dimensional time-average analysis with the surface as a perfect blackbody suggests the greenhouse effect in total has a 33 K warming effect at the surface, and a more precise account shows maybe 34 K, or 31 K, well, that hardly blows the whole notion of a greenhouse effect out of the water…
Hank Roberts@601
I believe I first ran across Syun when I was searching UK Fairbanks for permafrost references. IARC caught my attention, and I looked up the acronym. “The International Arctic Research Center [IARC] serves as a focal point of integrating/synthesizing arctic research efforts in terms of climate change and communicates the results to the global climate research community. Our core research group interacts with a larger number of scientists from many parts of the world, enabling climate change research to truly be an international effort.”
My goodness, an international arctic climate change organization in a 9000 person university. Since the top IPCC-4 scientists realized they were way off in their knowledge and ran off to the arctic as soon as they finished WK1, I decided to look more at the IARC which was located in a region that was not way off in their knowledge
I found the founder and director for 10 years was someone named Syun-Ichi Akasofu, an AK Fairbanks professor with 550+ papers and 9 PhD’s to his credit. Since I have managed data base programmers at Department, Group and Executive levels for an International corporation, I find setting up and successfully running a climate science shop including Russia, Japan, and US quite an impressive accomplishment.
Hank, I have much respect for your judgment and knowledge. When I called SA’s paper to your attention and you suggested caution I took a second look. I found one joint author paper in the 550+ about climate, embedded in a mass of aurora and uv radiation atmosphere peer-reviewed work. Until such time that you all discover that cloud forcing is negative feedback, you’ll have not much use for such research.
I read his paper (you call it notes) and was impressed. His linear plus multi-decadal fit to a temperature time series was amusing but nothing I thought I couldn’t do myself if I wanted to. What did impress me was the fact that he had examined a large number of contemporaneous records of ice/temperature events from the past couple of thousand years. I kept trying to get you to look at SA’s paper with no luck, as far as I could tell. Since CS’ers diss world renowned scientists like Jastrow, Seitz, Feynman, Dyson – not to mention Curry – I didn’t even bother to follow up.
When I found Mike Mann’s LIA work about the same paleo-time, I figured that SA’s work in that area would probably get enough critical attention. ( FWIW, I believe MM to be a careful researcher – after all, we learned the trade in the same department at the same university.) That’s why SA’s paper being “notes” didn’t bother me. Professors are always giving “notes” to grad students – that’s how the adviser system works. Either some grad student(s) will do thesis(s) on the contemporaneous stuff or we’ll never hear about it again. I can wait to see which.
OK?
Thanks for pointing me at Google Scholar, it’s often useful. It seems to give more pay-locked refs than raw Google which, being an SV person, I use all the time. Best spell checker I’ve found.
David B. Bensonsays
Septic Matthew (593) — Thank you for the interest. A typical way to determine the ECS of an AOGCM is to stabilize it and then inject a step of 2xCO2; then compute until equilibrium, which takes about 120 (simulated) decades. The range for the 23(?) AOGCMS is from 2.1 K to 4.4 K, if memory serves. From a wide variety of studies, ECS is close to 3 K: http://www.iac.ethz.ch/people/knuttir/papers/knutti08natgeo.pdf
My use of a decadal lag was motivated by a desire for simplicity, decades being quite a standard measure, together with the fact that such a lag approximately agrees with the physics of atmosphere plus shallow ocean; for greater precision I should have used somewhere between 11 and 13 years, but such intervals are not in common use and a decade is cloase enough. The formulas I used do not account properly for the deep ocean on millennial scales, so OGTR cannot be used as a very good predictor of ECS; nonetheless, ECS will be “close to” (3/2)OGTR and the result, 3.3 K, is “close to” the most likely value of around 3 K.
PS, remember, you still have to be careful with what Scholar brings up.
It includes far more than scholars would cite as sources in peer reviewed work.
Andreas Bjurströmsays
607 CM,
I could think of many plausible explanations … (because the earth sciences control IPCC) … but that wouldn’t be one of them.
I don´t have very much insight in the IPCC process, but I do know that there has been strong opposition from the earth sciences to include “soft” issues such as sustainable development among others. Don´t you think that the earth sciences (that dominant in number of studies, personal, reseach history, the fact that the IPCC is build upon institutions from the earth sciences, that the first IPCC chief was an earth scientist, etc, etc) are able to molde the IPCC according to their liking?
I would suggest that:
earth science -> the climate problem
biology -> the biodiversity problem
1 (discipline) -> 2 (problem)
1 -> 2 = the dominant discipline of problem X to some extent (an important degree) shape how we describe the problem, why we argue it is a problem, how we solve the problem …
John Petersays
Ray @603
Thanks for noticing, I believe – along with many others- you produce pretty good posts.
As usual, you ask a pretty good question, which I may have answered in a long post to Hank that I just finished.
You said:
Akasofu is a pretty reasonable solar scientist. He is not, however, a climate scientist.
I think he was a director of climate scientists for 10 years at IARC
You continue He’s been caught in some pretty basic errors (e.g. ignoring SO2 dimming), and he has declined to publish his work in climate science.
Don’t know, need more data. Does SO2 dim ir or uv?
You say:
However, to merely say that “we are recovering from the LIA” without proposing a forcing mechanism isn’t science.
As I told Hank, that’s what professors and directors do all the time. Besides I thought that no one knew why we came out of the LIA.
His main point, as I saw it was naturally temperatures rise when we leave an ice age, any ice age. SA calls it natural linear rise, wants to subtract it from the measured temperatures leaving a multi-decadal remainder that he doesn’t try to source. OTOH MM may be finding that cause right now – per his recent paleo paper.
My question to you is this: Why do you give more credence to a solar/aurora physicist on climate science than you do to climate scientists, particularly when the climate scientists have a very well supported and venerable theory that explains their observations and Akasofu is merely asserting a “recovery” and proposing no credible mechanism?
SA seems to have a much richer data with much broader scope. I’m a TP so I may not give enough credit to, theory. FWIW all major investment had a risk assessment VP and they melted down anyway.
Remember Ray, I’m trying to learn CS and repay youall for my education with advice from my life experiences. And the RC poster I probably owe the most to is Ray Ladbury.
OK?
Septic Matthewsays
608, Patrick027: If the 1-dimensional time-average analysis with the surface as a perfect blackbody suggests the greenhouse effect in total has a 33 K warming effect at the surface, and a more precise account shows maybe 34 K, or 31 K, well, that hardly blows the whole notion of a greenhouse effect out of the water…
How much of the 0.7C rise since 1850 is due to AGW?
209, Hank Roberts, Thanks for the Rabett links.
Jerry Steffenssays
Here’s a troubling story concerning the beliefs of TV weathercasters. Perhaps it merits a post?
From one of the Rabett links: Hank Roberts said…
&&&&
Guthrie’s right that
> “the last word wins” for the
> “lay people”
and in a quick look at dozens of threads on various blogs, the “last word” is very often an uncited claim by a persistent fabulist denying something well known.
&&&&
I think hosts figure it’s not worth their time to refute such, and they get tired, and they don’t want to post a personal refutation as the last thread, so they close it.
I shall have to leave and let you have the last word!
John Petersays
Hank Roberts @612
I am a techie. I believe good climate scientists are techies. They understand satellite measuring tools. They can design measurement experiments. They can design better measuring tools. They can program physics, chemistry and complex mathematics into big computer programs, run them in big powerful computers and understand the results.
They believed in and were successful at bigger and better climate science. They are in trouble cutting things down to (regional) size. Despite a lot of their best efforts, there remains an area where their physics/chemistry/math/equations/numerical analysis/ has failed them so far. CLOUDS
Maybe we could get Joni Mitchell to help us develop regional models: ”Bows and flows of angle hair
And ice cream castles in the air
And feather canyons everywhere
I’ve looked at clouds that way
But now they only block the sun
They rain and snow on every one
So Many things I would have done
But clouds got in my way
I’ve looked at clouds from both sides now
From up and down and still somehow
It’s cloud illusions I recall
I really don’t know clouds at all
Joni Mitchell – Clouds Album – ”Both Sides Now”
Ray Ladburysays
John Peter says, “His main point, as I saw it was naturally temperatures rise when we leave an ice age, any ice age.”
NO! John, the energy has to come from somewhere. In the case of the onset of a normal interglacial, it is a slight increase in insolation sufficient to begin melting the ice, followed and enhanced by many feedbacks (including increase in CO2). If you don’t have a mechanism, you aren’t doing science, you’re doing numerology.
It is much more impressive for its heft than for its insight.
Septic Matthewsays
Sorry I’m back so soon. I have to admit to one mistake. I had not realized that G&T had attempted to refute the entire greenhouse gas effect using the second law. The paper I cited merely details all the difficulties of working with an “average temperature” when the radiation is proportional to T^4 and the natural variations are on the order of tens of K.
Claiming, as Kramm et al do, that they have refuted all of Smith’s refutation of G&T is probably unjustifiable, just as Ray Ladbury wrote.
Sorry I wasted your time.
Matthew
Patrick 027says
Re 615 – most of it.
John Petersays
Ray@619
Read Wikipedia on Little Ice Age (You can edit it if you think it wrong)
I believe it occurred, the description seems pretty complete and the beginning and end confused. It was 1C colder which is what SA charts with his fit.
“Scientists have tentatively identified these causes of the Little Ice Age: decreased solar activity, increased volcanic activity, altered ocean current flows, the inherent variability of global climate, and reforestation following decreases in the human population. One of the difficulties in identifying the causes of the Little Ice Age is the lack of consensus on what constitutes “normal” climate, or if one exists…it is very difficult to know what the true level of variability from only internal causes might be, since other forcings, as noted above, exist; and their magnitude may not be known either. One approach to evaluating internal variability is to use long integrations of coupled ocean-atmosphere global climate models. These have the advantage that the external forcing is known to be zero; but the disadvantage that they may not fully reflect reality. These variations may result from chaos-driven changes in the oceans, the atmosphere, or interactions between the two. Two studies have concluded that the demonstrated inherent variability is not great enough to account for the Little Ice Age. Beginning around 1850, the climate began warming and the Little Ice Age ended.
Some global warming critics believe that Earth’s climate is still recovering from the Little Ice Age and that human activity is not the decisive factor in present temperature trends, but this idea is not widely accepted. Mainstream scientific opinion on climate change is that warming over the last 50 years is caused primarily by the increased proportion of CO2 in the atmosphere caused by human activity. There is less agreement over the warming from 1850 to 1950.”
You tell me what forced LIA to stop and why you believe we’re not recovering still.
Ray Ladburysays
John Peter,
Careful on satellite measurements. We went 8 years with pretty much bupkes new for Earth observation, and what we have is not tailored to climate measurements. The experience of the UAH team is a good indication of the difficulties one can run into when turning satellite measurements into a climate “product”. And with the launch of the OCO (now dubbed the “Oceanic Carbon Observatory” by wags), there will be a deficit for a few more years.
There are a few birds going up that will have more ability to look in the IR. ICESAT2 is on the boards. OCO2 is under development. Global Precipitation Monitor is moving along, and the Solar Dynamics Observatory and other birds are looking at Mr. Sun. And it looks like DSCOVR might actually be allowed to look at Earth after all.
Even so, what is needed is a long-term, sustained program of observation using purpose-built satellites, and I don’t see that in the offing.
Ray’s pointer is the right place to look; don’t miss the following posting, also by John Mashey in the same thread, more specific to Akasofu’s paper. John did it as an exercise in how to work through a document and think about what you’re reading. Direct link, save for reference: http://tamino.wordpress.com/2007/05/01/glaciers-al-gore-got-it-right/#comment-1754
1) Thanks, I’ve seen this before, but maybe this worth going through as though I’d never seen it, as an illustration of skeptical analysis…..”
Ray Ladburysays
John Peter,
A rising temperature does not just happen. It requires a forcing? We know that increased insolation and decreased volcanism were occurring early in the century. We know that climate responds on a timescale of roughly a year (corresponding to the atmosphere and the shallow ocean) and has another relevant timescale of about 30 years. Given those timescales, what form would you expect the temperature rise to assume? Wouldn’t you expect a more rapid rise early on followed by a slow approach to a new equilibrium temperature? Yet that is not what we see. Instead, we see the most rapid rise in temperature in the past 3 decades. Why the delayed warming?
If you are going to posit a timescale substantially longer than 30 years, be careful. After all, Akasofu’s argument does nothing to invalidate all of the independent lines of evidence that show CO2 sensitivity is between 2 and 4.5 degrees per doubling. So if Akasofu is right, we are in fact further from equilibrium than we thought, and CO2 sensitivity must be on the high side of that confidence interval. Thus, we will warm more slowly, but the eventual damage will be worse.
Ultimately, Akasofu makes the mistake so many denialists make–focusing only on the temperature rise of the late 20th century. This forms only a tiny portion of the evidence that shows we are warming the planet. The evidence as a whole hangs together, and the only theory that comes close to explaining all of it is the consensus theory…which of course is why we have consensus.
Like this precious gem: “The most prominent warming (twice the global average) took place in the Arctic, particularly in the continental arctic, during the last half of the 20th century, as stated in the IPCC Report, but it disappeared during the last decade or so.”
There’s no science to argue. It’s garbage.
Patrick 027says
Re Septic Matthew – Yes, it’s not that G&T are not correct in pointing out that there are some complexities that can make a global average climate different than what it would be if all points on the globe were forced by global average forcings and then made to undergo the same responses (for one thing, that would obviate the coriolis effect, which varies over latitude), and with the added approximations of the surface as a perfect blackbody in LW, etc. But we already knew that. And it turns out the corrections for the global average surface temperature are not so big, but of course we need the whole globe and year, etc, to look at diurnal, seasonal, latitudinal, regional, transient and low-frequency variability – related effects in total and in response to changes (one can progress from a 1-dimensional time-average model to a 2-dimensional model (zonal average) to a 3-dimensional model, learning more and refining previous lessons each time, but the simple models help illustrate a portion of what is happenning in the more complex models and in reality.)) The Smith paper so far as I recall was not intended to describe a comprehensive climate model, but to merely illustrate how some of the laws of physics apply to climate (in particular, how the equilibrium average temperature changes if the temperature variation is changed), which is something G&T utterly screwed-up when they tried to apply the second law of thermodynamics and started refering to ‘superinsulation’, and apparent arguments which would seem to imply that nothing can ever actually emit any radiation – stuff that not only goes against established and uncontroversial physical theory and law, but even casual everyday experience combined with cause-and-effect logic (a photon emission can’t depend on conditions far away and in the future).
With regards to 2nd Law, the second law does not occur by way of a physical force (like gravity or electromagnetism) that attracts or repels energy. Rather, it works by default – it just happens because of statistics. Concievably (??), many if not nearly all hypothetical universes with all sorts of different physics would have to have a second law of thermodynamics (you could destroy entropy by creating a new physical law, but once that law is in place, entropy could no longer by destroyed).
Essentially, the second law is a consequence of the low probability of a system shifting into a ‘special’ state (a subset of possibilities that have a distinctly different ‘climate’) if it is not already in such a state. Entropy cannot be destroyed in net within a closed isolated system.
But in thermodynamic equilibrium, it is not the case that all processes shut down. Photons are emitted and absorbed and scattered, electrons and atoms and molecules gain and lose energy, chemical reactions occur, materials change phase, molecular collisions and diffusion transport internal energy and mass. But in equilibrium, all processes occur in forward and reverse directions equally. And even in disequilibrium, while one process may occur at a greater rate, the reverse can still happen.
G&T apparently must think ‘backradiation’ was made up to explain the greenhouse effect, but it is a consequence of established physics.
Re Septic Matthew by way of Re John E. Pearson 599
‘Greenhouse effect’ Is it a misnomer? I’m not sure it is. Of course an actual greenhouse works differently, as does a winter coat, from how the atmospheric greenhouse effect works, but they all follow a basic pattern: Energy goes in one way (solar radiation, metabolism, solar radiation again), is processed into a different form (generally gaining entropy) and it can’t all get out the same way it got in, and the way it can get out can be closed or open as if by a valve that can be largely independent of the valve that controls the energy inflow. So the energy can be forced to build up or be depleted to achieve equilibrium between inflow and outflow by adjusting the inflow valves (optical properties for SW radiation, metabolism) and the outflow valves (optical properties for LW radiation, thermal conductivity, convection) seperately.
Telegraph report on funding of climate change sceptics:
“An oil conglomerate (Koch Industries) has allegedly spent nearly $25 million on campaigns to discredit climate change and clean energy policies…between 2005 and 2008, according to a new report (Greenpeace).”
“…Koch Industries did not reject Greenpeace’s claims about its support for climate opposition groups but said its report “distorts the environmental record of our companies”.
Greenpeace…supplied a list of 35 organisations and 21 politicians – 17 Republicans and four Democrats – who it claimed received money, either directly or indirectly, from Koch or foundations it had set up.
“They include the Cato Institute, a conservative think-tank, and Americans for Prosperity, a free-market campaign group.”
Thanks for all your references to SA and his work. Collectively they make a powerful case for ignoring SA’s recent “climate research”. In particular, I found Mashey’s analysis creditable, fair and pretty complete. As Ben Santer might put it, the weight of the evidence is compelling.
Quite graciously and most fairly, youall have demonstrated that, while SA’s ideas might have appealed to me, any such appeal was more likely due to what I wanted to believe than to any intrinsic scientific merit in the ideas themselves.
Excellent work again. Thanks much.
CMsays
Andreas (#613), re: reasons for disciplinary inclusion/exclusion in IPCC:
>I don´t have very much insight in the IPCC process
Me neither. So we’re trading speculations, and we’ve come as far as that will take us. You have a hypothesis, I have offered some alternative hypotheses. We won’t resolve this with general reflections on the disciplinary construction of research subjects. And we’ll bore others stiff.
If you have references regarding the stipulated disciplinary resistance you’ve heard or read about (against Russian historical approach, sustainable development approach, softies in general, etc.), I’ll read up.
Meanwhile, here’s an interesting article by a countrywoman of yours that indicates: some pragmatic, uncontroversial (?) ways anthropology could contribute to mitigation research; the importance of a gender approach; and – yes – a ‘soft’ scientist’s experience of techies questioning the relevance of her work.
Annette Henning, “Climate change and energy use: The role for anthropological research,” Anthropology Today 21, no. 3 (2005): 8-12. DOI: 10.1111/j.0268-540X.2005.00352.x
Robertsays
Does anyone by any chance know where I can find temperature data for some of the longest meteorological stations. I know that the central england station data can be received through the met office but I am trying to use a methodology similar to Jones and Bradley (1992) which looks at as many of the long records as possible. Cru and Giss don’t go as far back as the farthest datasets such as the ones from Trondheim (1761), Stockholm (1756), De Bilt (1706), Leningrad (1743), Berlin (1701), Cape Town (1857), Toronto (1770), Boston (1743), New Haven (1781), Rio de Janeiro (1832)… for example… I have tried the Global Historical Climate Network but haven’t been able to find what i’ve been looking for. Any ideas?
Ray Ladburysays
John Peter,
Glad we were able to help. You can certainly do worse than to consult what John Mashey has to say.
BTW, the first author on the execrable piece of crap that Septic Matthew has been flogging is Gerhard Kramm–one of the primary group of denialists around Akasofu. The denialosphere is indeed a very, small, small world.
Read my lips: Akasofu talks nonsense on climate science. He says the Arctic (!) isn’t warming. He says permafrost is melting due to the exhaust heat from buildings. He says carbon dioxide doesn’t influence climate. Good solar physicist. In climatology, he’s a loony. Period.
SM (615): How much of the 0.7C rise since 1850 is due to AGW?
BPL: Pretty much all of it.
John E. Pearsonsays
629: Patrick 027 on “misnomer”.
Goody’s exact words (Atmospheres, 1971) which I quoted were “Some writers prefer to avoid this term because the analogy to the domestic greenhouse is not complete …”
I recall various atmospheric physicists saying similar things to me personally when I was an undergrad at Texas A&M. Perhaps “misnomer” isn’t the right word, but clearly enough the term isn’t an exact analogy and I presume that has been known since the first time the term “greenhouse effect” was used. To write 100 pages about it in the 21st century is pretty silly as is writing 10 or 15 more in defense of the 100!
Completely Fed Upsays
“but clearly enough the term isn’t an exact analogy”
If the analogy were exact, it would be a tautology, surely?
John Petersays
602 Richard Ordway, Gavin
Jim Hansen pg 246, paragraph 2 is a statement of support for civil disobedience when we fail to do right through electoral processes.
Civil disobedience is a fine old American custom and is supported in the constitution’s bill of rights: “Civil Disobedience is the act of disobeying a law on grounds of moral or political principle. It is an attempt to influence society to accept a dissenting point of view. Although it usually uses tactics of nonviolence, it is more than mere passive resistance since it often takes active forms such as illegal street demonstrations or peaceful occupations of premises. The classic treatise on this topic is Henry David Thoreau’s “On the Duty of Civil Disobedience,” which states that when a person’s conscience and the laws clash, that person must follow his or her conscience. The stress on personal conscience and on the need to act now rather than to wait for legal change are recurring elements in civil disobedience movements. The U.S. Bill of Rights asserts that the authority of a government is derived from the consent of the governed, and whenever any form of government becomes destructive, it is the right and duty of the people to alter or abolish it.”
Re “To write 100 pages about it in the 21st century is pretty silly as is writing 10 or 15 more in defense of the 100!”
Yes! I promise I won’t write any more than 9 pages on the subjet :) !
BobFJsays
PART 2:
I’d like to move-on to Tamino’s second figure,
where he writes; The 30-yr smooth looks quite a bit different:
It is apparent that the value of zero at 1880 could only apply if there was zero volcanic forcing for at least the previous 30 years if PMA (Prior Moving Average) smoothing was used. (or 15 years if CMA was used). Perhaps this is true, however, in his replacing third figure he starts the x axis origin at 1900 ILO 1880, and writes:
We note that there’s a large decrease early in the data. This is not necessarily reflective of an actual decrease, it’s because for the earliest few decades we’re estimating a 30-yr smooth based on considerably less than 30 yrs. of data. To approximate the 30-yr smooth with any accuracy, we should only use the data from about 1900 on, giving us 30-yr smoothed values based on at least 20 years of data. That looks like this:
Testing: embedded link to tamino’s fig 2 removed
BobFJsays
PART 3 This seems strange because whilst 20 years of real data is made available, (although hidden) it does not suit either PMA or CMA 30-year smoothing. There also seems to be a question as to what units are used, OR how the volcanic forcing can increase significantly when it is smoothed. Also, what weighting and why. Here is an approximate graphical comparison of unweighted PMA & CMA smoothing etc.
I’ve Emailed Tamino, asking for some clarification. Any thoughts?
Patrick 027says
Re John Peter: “Please keep up your radiation discussions.”…
Thank you; anything you had in mind?
(I’ve been thinking about trying to put something brief (enough for a couple comments) about atmospheric fluid dynamics together (Outline: enthalpy, kinetic energy, hydrostatic approximation, gravity waves, coriolis effect, geostrophic adjustment, momentum, potential vorticity, Rossby waves, wave-mean interaction) but that has a tendency to snowball…)
John Petersays
Patrick 027 @644
I appreciate your posts. They seemed pretty basic radiation balance to me. I’m a slow reader and you’ve already given me a week or two to digest.
I am trying to put together a table of radiation energy balance from Trenberth 2008 with ranges to try to get as simple an uncertainty build-up as possible. I would use your posts to cross check.
Since clouds are a key technical modeling problem a survey of what the models are really doing against what could be done should be of interest. Are any of the climate models 3D yet? What is the effect on the albedo? I’ve seen one paper on fractal clouds, are any models using them?
I’m very satisfied (and overwhelmed) with your topics to date so whatever you choose will be great by me. I only listed some suggestions because you have been so helpful I couldn’t turn down your request.
My advice would be to continue doing your own choices, they are great by me.
First, CORRECTION: I earlier wrote something to the effect of non-geometric optics being required to achieve the limiting concentration of solar radiation over a finite area; what I should have said was non-imaging optics are required (so far as I know); they can still be geometric (as in designed via ray-tracing, which is what I then did and will do here).
1. CSP with parabolic dish or trough reflector:
Earlier I gave equations describing concentration factor for a target that is a flat surface facing downward, crossing through the focus (relative to the dish or trough; upward (y) in this frame of reference is toward the sun, the direction across the trough or through the dish is x, and when it comes up, (0,0) is the focus).
In general, (describing the parabolic dish reflector; for a trough, the cross section through the trough and it’s targe is identical to a cross section through the axis of the dish and it’s target; conical surfaces become pairs of rectangular flat surfaces, a circular surface becomes a rectangular flat surface, a spherical surface becomes a cylindrical surface):
A parabolic dish with an aperture of radius a and length from center of dish to focal point r, with edges height h above the center:
g = a/r
G = 1/g – g/4
—————–
h/a = g/4
r/a = 1/g
(r-h)/a = 1/g – g/4 = G
r-h = a*G = the vertical distance from the edge of the dish to the focal point.
——————–
H is distance from edge of dish/trough to focal point
H = sqrt( a^2 + (a*G)^2 )
H/a = sqrt(1-G^2)
1/G = tan(b), where b is the angle from vertical for the reflected ray from the center of the sun off the edge of the dish; it is the angle from vertical of the line from the dish edge to the focal point.
————
q is the angular radius of the solar disk
sin(q) = Solar radius / distance from Earth to center of sun
————
A non-optimal but sufficient target that intercepts all reflected solar radiation is a sphere of radius Rts centered at the focal point:
Rts/H = sin(q)
Rts/a
= H/a * sin(q)
= sqrt(1-G^2) * sin(q)
—————-
A portion of the sphere does not recieve any reflected radiation; this is the portion within an angle J from the top of the sphere; this could be used to recieve direct solar rays, but excluding it:
Other angles will be substituted in these formulas below.
—————
This is not yet a minimal area (for sufficiently small a, at least, including a = 2r, where G = 0).
—————
Consider angle JJ, the angle from the bottom of the sphere that is grazed by the lowest reflected ray off the dish edge:
ANGLES J and JJ:
(b-q) + J = pi/2
J = pi/2 + q – b
(b+q) + JJ = pi/2
JJ = pi/2 – (b+q)
—————–
Also consider an angle K on the sphere, from downward.
CASE 1 (perhaps (?) an optimal reduction of target area for intermediate aperture sizes; K will be different between the dish and trough cases and will be a function of G and q):
K is selected to minimize target surface area (K > JJ, if K is found to be only a little more than JJ, or smaller, then an alternative geometry is better (CASE 2).)
A flat circular surface of area Ab replaces the spherical surface within the angle JJ; this has radius Rts*sin(JJ)
The spherical surface above angle K is replaced by a conical surface, which is tangent to the sphere at K and extends upward just to reach the highest reflected ray. The radius of the lower edge is u and the radius of the upper edge is p. The area is Ac.
The remaining spherical area used is As.
—-
CASE 2 – a flat circular target area is used, with radius p, in the plane of the upper edge of the cone in CASE 1, where K = JJ. The edge of this target is at the intersection of the highest reflected ray from the edge of the dish on one side and the lowest reflected ray from edge of the dish on the opposite side.
———
Equations (I can’t guarantee that I didn’t make an algebraic error, especially here):
u = -xL = Rts*sin(K)
The position of the upper edge of the truncated cone, in cross section, is found at the intersection of these lines (both lines are tangent to the circular cross section of the sphere, the first runs through the conical surface, the second is a reflected ray from the edge of the dish, in a coordinate system with the origin at the focus, y upward, reflected ray coming from the negative x direction):
sin(q) = solar radius / distance to center of sun
————
Rts/a
= H/a * sin(q)
= sqrt(1-G^2) * sin(q)
—————-
And the limiting efficienty, relative to intercepted direct solar radiation, for perfect blackbody target (and perfect reflector, too!) is
(1 – Tc/Th) * [1 – (Th/Ts')^4 ]
where S = incident direct solar flux per unit area
and S*C = 5.67e-8 W/(m2 K4) * Ts'^4
Yes, I could tidy that up a bit (set a = 1 and then just deal with relative sizes, try solving for K (YIKES!), etc., but it's not like I'm getting paid here, so…
Anyway, it now occurs to me that the the target area for CASE 1 can be trimmed a bit more and still intercept all reflected rays (the radius of the circular area and the top of the conical surface and vertical positions of those must be the same, but the spherical and conical surfaces could be flattened a bit.
Note that the radiation emitted and absorbed by the target is limited by a minimum convex or flat surface that wraps around the actual surface; provided that the silhouette (sp?) of the target is not cut into as seen from any direction (no long grooves that wrap around a curve or penetrate to an edge), dents can be put into the surface to increase the effective absorptivity and emissivity of the convex/flat surface.
And the efficiency can be increased if the target is tightly wrapped in a greenhouse or otherwise has lower absorptivity at longer wavelengths, or if the target surface is not isothermal (with fluid coming through the cold parts first and exiting at the hottest parts – in which case, the target surface should probably pass through the actual focal point), etc.
Patrick 027says
In the partial surface area of a sphere, the line:
is not actually equal to the next line, but was work done in formulating the next line.
Sorry about the length; I was interested, I worked on it, I wanted to share, now I’m done with the geometric optics for CSP stuff. Hope this didn’t end the thread.
John Petersays
BPL@635
Strange. Have you looked at any of the other IARC research published in peer-reviewed climate science journals? That doesn’t seem to be what SA’s researchers publish, i.e. regional studies of ice and oceans using global models, etc.
> John Peter
> Akasofu
> expert climate scientist evaluation who either have already done
> the work or mindlessly reject anything he claims.
Like I said, Google would dearly love to befriend you. You can look this up.
Yes, if Google is part of a global scientific mindless conspiracy, along with every scientist who could follow his math and evaluate the claim, and every journal editor — then you won’t find much support for his ideas.
You have to weigh the possibilities that you consider may be real.
— massive mindless conspiracy of every possible person, or
— big yawn by people who’ve evaluated the ideas
Go with the probabilities.
What do you consider may be possibly real?
You include the massive worldwide conspiracy in your reality?
I don’t endorse the thoughts of the two following people…but these are two of the brightest brains who usually accurately predict trends by about 15-20 years.
World famous thinker/former peer-reviewed scientist James Lovelock says:
“I don’t think we’re yet evolved to the point where we’re clever enough to handle a complex a situation as climate change,” said Lovelock in his first in-depth interview since the theft of the UEA emails last November. “The inertia of humans is so huge that you can’t really do anything meaningful.”
One of the main obstructions to meaningful action is “modern democracy”, he added. “Even the best democracies agree that when a major war approaches, democracy must be put on hold for the time being. I have a feeling that climate change may be an issue as severe as a war. It may be necessary to put democracy on hold for a while.”
Lovelock, 90, believes the world’s best hope is to invest in adaptation measures, such as building sea defences around the cities that are most vulnerable to sea-level rises. He thinks only a catastrophic event would now persuade humanity to take the threat of climate change seriously enough, such as the collapse of a giant glacier in Antarctica, such as the Pine Island glacier, which would immediately push up sea level.
“That would be the sort of event that would change public opinion,” he said. “Or a return of the dust bowl in the mid-west. Another Intergovernmental Panel on Climate Change (IPCC) report won’t be enough. We’ll just argue over it like now.” The IPCC’s 2007 report concluded that there was a 90% chance that greenhouse gas emissions from human activities are causing global warming, but the panel has been criticised over a mistaken claim that all Himalayan glaciers could melt by 2030.
http://www.guardian.co.uk/science/2010/mar/29/james-lovelock-climate-change
I know James Hansen has made a similar statement about democracy (storms of my grandchildren).
[Response: No he didn’t, despite what you might have read elsewhere. – gavin]
John Peter,
Akasofu is a pretty reasonable solar scientist. He is not, however, a climate scientist. He’s been caught in some pretty basic errors (e.g. ignoring SO2 dimming), and he has declined to publish his work in climate science. However, to merely say that “we are recovering from the LIA” without proposing a forcing mechanism isn’t science.
My question to you is this: Why do you give more credence to a solar/aurora physicist on climate science than you do to climate scientists, particularly when the climate scientists have a very well supported and venerable theory that explains their observations and Akasofu is merely asserting a “recovery” and proposing no credible mechanism?
599, John E. Pearson: The authors of the paper you linked to spend pages and pages on stuff that is completely trivial, showing for example that the product of integrals isn’t equal to the integral of the product, etc.
On the whole, I think I like my characterization better: the authors attempt to quantify the effects of the variations in temperature across regions of the earth. They do so to show that Smith’s rebuttal can’t be precise enough to achieve its stated aim. Applied math is all about approximations, and they conclude that Smith’s simplifications lead to approximations that are too coarse. One of the details of their argument, which they claim Smith overlooked, is a fact of calculus that you claim is taught in high school. That it is taught in high school is not relevant to anything, except possibly to show that Smith’s paper ought not to have been believed by anyone who studied high school calculus.
G&T might be wrong, but Smith’s rebuttal is inadequate to prove them wrong.
597, Completely Fed Up: With a physical model you don’t have to guess.
Even with a physical model (and there isn’t an adequate physical model for the response time) the parameters would still have to be estimated, not guessed. Without a physical model, examining the cross-lagged correlations is a way to estimate the response time. Maybe not real accurate, yet maybe the best available so far. RPB only supplied 13 data points. The cointegrated VAR models might give a better estimate.
China Huaneng Group, the nation’s biggest power generator, targets a capacity to produce about 35 percent of its electricity from clean energy by 2020 as the country seeks to cut pollution, President Cao Peixi said.
http://www.bloomberg.com/apps/news?pid=20601080&sid=aVB4v6GHv_O8
“G&T might be wrong,”
No “might” in it.
” but Smith’s rebuttal is inadequate to prove them wrong.”
Please explain why.
Because as far as most of the educated world considers, Smith’s rebuttal is adequate.
“Even with a physical model (and there isn’t an adequate physical model for the response time)”
Says the man who insists there’s a good model of climate in fourier analysis…
I rest my case.
Andreas,
> So why is Anthropology excluded and earth sciences included in the IPCC?
Rephrasing. Why does the IPCC discuss climate change a lot in terms of earth sciences and very little in terms of anthropology?
Because it’s obvious how it is an earth science problem, but not quite so obvious where anthropology comes in? Because earth scientists describe their work as having to do with anthropogenic climate change, and anthropologists do not (that was what I suggested)? Because anthropologists compete with other social scientists, like economists, who have pretty sharp elbows when it comes to getting to formulate the basis for policy? I could think of many plausible explanations…
> because the earth sciences control IPCC.
…but that wouldn’t be one of them.
> paleoclimate studies from the earth sciences are largely excluded
> from the IPCC.
Huh? What’s chapter 6 then?
Re Septic Matthew –
The original G&T was so utterly wronger than wronger than wrong that even imprecise work is adequate to illustrate that they were just completely off the tracks of science and logic.
If the 1-dimensional time-average analysis with the surface as a perfect blackbody suggests the greenhouse effect in total has a 33 K warming effect at the surface, and a more precise account shows maybe 34 K, or 31 K, well, that hardly blows the whole notion of a greenhouse effect out of the water…
> SM
> Gerlich and Tscheuschner
“I don’t understand” isn’t the same as saying the paper isn’t adequate.
Read a bit of the background; published papers assume much they don’t include.
E.g.
http://rabett.blogspot.com/2009/12/god-will-know-his-own.html
http://rabett.blogspot.com/2008/03/formal-reply-to-gerlich-and-tscheuner.html
Hank Roberts@601
I believe I first ran across Syun when I was searching UK Fairbanks for permafrost references. IARC caught my attention, and I looked up the acronym.
“The International Arctic Research Center [IARC] serves as a focal point of integrating/synthesizing arctic research efforts in terms of climate change and communicates the results to the global climate research community. Our core research group interacts with a larger number of scientists from many parts of the world, enabling climate change research to truly be an international effort.”
My goodness, an international arctic climate change organization in a 9000 person university. Since the top IPCC-4 scientists realized they were way off in their knowledge and ran off to the arctic as soon as they finished WK1, I decided to look more at the IARC which was located in a region that was not way off in their knowledge
I found the founder and director for 10 years was someone named Syun-Ichi Akasofu, an AK Fairbanks professor with 550+ papers and 9 PhD’s to his credit. Since I have managed data base programmers at Department, Group and Executive levels for an International corporation, I find setting up and successfully running a climate science shop including Russia, Japan, and US quite an impressive accomplishment.
Hank, I have much respect for your judgment and knowledge. When I called SA’s paper to your attention and you suggested caution I took a second look. I found one joint author paper in the 550+ about climate, embedded in a mass of aurora and uv radiation atmosphere peer-reviewed work. Until such time that you all discover that cloud forcing is negative feedback, you’ll have not much use for such research.
I read his paper (you call it notes) and was impressed. His linear plus multi-decadal fit to a temperature time series was amusing but nothing I thought I couldn’t do myself if I wanted to. What did impress me was the fact that he had examined a large number of contemporaneous records of ice/temperature events from the past couple of thousand years. I kept trying to get you to look at SA’s paper with no luck, as far as I could tell. Since CS’ers diss world renowned scientists like Jastrow, Seitz, Feynman, Dyson – not to mention Curry – I didn’t even bother to follow up.
When I found Mike Mann’s LIA work about the same paleo-time, I figured that SA’s work in that area would probably get enough critical attention. ( FWIW, I believe MM to be a careful researcher – after all, we learned the trade in the same department at the same university.) That’s why SA’s paper being “notes” didn’t bother me. Professors are always giving “notes” to grad students – that’s how the adviser system works. Either some grad student(s) will do thesis(s) on the contemporaneous stuff or we’ll never hear about it again. I can wait to see which.
OK?
Thanks for pointing me at Google Scholar, it’s often useful. It seems to give more pay-locked refs than raw Google which, being an SV person, I use all the time. Best spell checker I’ve found.
Septic Matthew (593) — Thank you for the interest. A typical way to determine the ECS of an AOGCM is to stabilize it and then inject a step of 2xCO2; then compute until equilibrium, which takes about 120 (simulated) decades. The range for the 23(?) AOGCMS is from 2.1 K to 4.4 K, if memory serves. From a wide variety of studies, ECS is close to 3 K:
http://www.iac.ethz.ch/people/knuttir/papers/knutti08natgeo.pdf
My use of a decadal lag was motivated by a desire for simplicity, decades being quite a standard measure, together with the fact that such a lag approximately agrees with the physics of atmosphere plus shallow ocean; for greater precision I should have used somewhere between 11 and 13 years, but such intervals are not in common use and a decade is cloase enough. The formulas I used do not account properly for the deep ocean on millennial scales, so OGTR cannot be used as a very good predictor of ECS; nonetheless, ECS will be “close to” (3/2)OGTR and the result, 3.3 K, is “close to” the most likely value of around 3 K.
> until such time as you all discover that cloud forcing is negative feedback
If there’s a paper in there, yes, he or someone will write it. If there’s an idea in there, one of the scientists who’s read it will comment on it.
Unless of course that vast global conspiracy prevents any mention of the idea.
http://scholar.google.com/scholar?q=cloud+forcing+negative+feedback
PS, remember, you still have to be careful with what Scholar brings up.
It includes far more than scholars would cite as sources in peer reviewed work.
607 CM,
I could think of many plausible explanations … (because the earth sciences control IPCC) … but that wouldn’t be one of them.
I don´t have very much insight in the IPCC process, but I do know that there has been strong opposition from the earth sciences to include “soft” issues such as sustainable development among others. Don´t you think that the earth sciences (that dominant in number of studies, personal, reseach history, the fact that the IPCC is build upon institutions from the earth sciences, that the first IPCC chief was an earth scientist, etc, etc) are able to molde the IPCC according to their liking?
I would suggest that:
earth science -> the climate problem
biology -> the biodiversity problem
1 (discipline) -> 2 (problem)
1 -> 2 = the dominant discipline of problem X to some extent (an important degree) shape how we describe the problem, why we argue it is a problem, how we solve the problem …
Ray @603
Thanks for noticing, I believe – along with many others- you produce pretty good posts.
As usual, you ask a pretty good question, which I may have answered in a long post to Hank that I just finished.
You said:
Akasofu is a pretty reasonable solar scientist. He is not, however, a climate scientist.
I think he was a director of climate scientists for 10 years at IARC
You continue
He’s been caught in some pretty basic errors (e.g. ignoring SO2 dimming), and he has declined to publish his work in climate science.
Don’t know, need more data. Does SO2 dim ir or uv?
You say:
However, to merely say that “we are recovering from the LIA” without proposing a forcing mechanism isn’t science.
As I told Hank, that’s what professors and directors do all the time. Besides I thought that no one knew why we came out of the LIA.
His main point, as I saw it was naturally temperatures rise when we leave an ice age, any ice age. SA calls it natural linear rise, wants to subtract it from the measured temperatures leaving a multi-decadal remainder that he doesn’t try to source. OTOH MM may be finding that cause right now – per his recent paleo paper.
My question to you is this: Why do you give more credence to a solar/aurora physicist on climate science than you do to climate scientists, particularly when the climate scientists have a very well supported and venerable theory that explains their observations and Akasofu is merely asserting a “recovery” and proposing no credible mechanism?
SA seems to have a much richer data with much broader scope. I’m a TP so I may not give enough credit to, theory. FWIW all major investment had a risk assessment VP and they melted down anyway.
Remember Ray, I’m trying to learn CS and repay youall for my education with advice from my life experiences. And the RC poster I probably owe the most to is Ray Ladbury.
OK?
608, Patrick027: If the 1-dimensional time-average analysis with the surface as a perfect blackbody suggests the greenhouse effect in total has a 33 K warming effect at the surface, and a more precise account shows maybe 34 K, or 31 K, well, that hardly blows the whole notion of a greenhouse effect out of the water…
How much of the 0.7C rise since 1850 is due to AGW?
209, Hank Roberts, Thanks for the Rabett links.
Here’s a troubling story concerning the beliefs of TV weathercasters. Perhaps it merits a post?
http://www.nytimes.com/2010/03/30/science/earth/30warming.html?hp
609, Hank Roberts
From one of the Rabett links: Hank Roberts said…
&&&&
Guthrie’s right that
> “the last word wins” for the
> “lay people”
and in a quick look at dozens of threads on various blogs, the “last word” is very often an uncited claim by a persistent fabulist denying something well known.
&&&&
I think hosts figure it’s not worth their time to refute such, and they get tired, and they don’t want to post a personal refutation as the last thread, so they close it.
I shall have to leave and let you have the last word!
Hank Roberts @612
I am a techie. I believe good climate scientists are techies. They understand satellite measuring tools. They can design measurement experiments. They can design better measuring tools. They can program physics, chemistry and complex mathematics into big computer programs, run them in big powerful computers and understand the results.
They believed in and were successful at bigger and better climate science. They are in trouble cutting things down to (regional) size. Despite a lot of their best efforts, there remains an area where their physics/chemistry/math/equations/numerical analysis/ has failed them so far.
CLOUDS
Maybe we could get Joni Mitchell to help us develop regional models:
”Bows and flows of angle hair
And ice cream castles in the air
And feather canyons everywhere
I’ve looked at clouds that way
But now they only block the sun
They rain and snow on every one
So Many things I would have done
But clouds got in my way
I’ve looked at clouds from both sides now
From up and down and still somehow
It’s cloud illusions I recall
I really don’t know clouds at all
Joni Mitchell – Clouds Album – ”Both Sides Now”
John Peter says, “His main point, as I saw it was naturally temperatures rise when we leave an ice age, any ice age.”
NO! John, the energy has to come from somewhere. In the case of the onset of a normal interglacial, it is a slight increase in insolation sufficient to begin melting the ice, followed and enhanced by many feedbacks (including increase in CO2). If you don’t have a mechanism, you aren’t doing science, you’re doing numerology.
Does it not bother you that Akasofu doesn’t even think enough of his own analysis to publish it in a peer-reviewed journal? I would urge you to read what John Mashey had to sab about Akasofu
http://tamino.wordpress.com/2007/05/01/glaciers-al-gore-got-it-right/#comment-1739
It is much more impressive for its heft than for its insight.
Sorry I’m back so soon. I have to admit to one mistake. I had not realized that G&T had attempted to refute the entire greenhouse gas effect using the second law. The paper I cited merely details all the difficulties of working with an “average temperature” when the radiation is proportional to T^4 and the natural variations are on the order of tens of K.
Claiming, as Kramm et al do, that they have refuted all of Smith’s refutation of G&T is probably unjustifiable, just as Ray Ladbury wrote.
Sorry I wasted your time.
Matthew
Re 615 – most of it.
Ray@619
Read Wikipedia on Little Ice Age (You can edit it if you think it wrong)
I believe it occurred, the description seems pretty complete and the beginning and end confused. It was 1C colder which is what SA charts with his fit.
“Scientists have tentatively identified these causes of the Little Ice Age: decreased solar activity, increased volcanic activity, altered ocean current flows, the inherent variability of global climate, and reforestation following decreases in the human population. One of the difficulties in identifying the causes of the Little Ice Age is the lack of consensus on what constitutes “normal” climate, or if one exists…it is very difficult to know what the true level of variability from only internal causes might be, since other forcings, as noted above, exist; and their magnitude may not be known either. One approach to evaluating internal variability is to use long integrations of coupled ocean-atmosphere global climate models. These have the advantage that the external forcing is known to be zero; but the disadvantage that they may not fully reflect reality. These variations may result from chaos-driven changes in the oceans, the atmosphere, or interactions between the two. Two studies have concluded that the demonstrated inherent variability is not great enough to account for the Little Ice Age. Beginning around 1850, the climate began warming and the Little Ice Age ended.
Some global warming critics believe that Earth’s climate is still recovering from the Little Ice Age and that human activity is not the decisive factor in present temperature trends, but this idea is not widely accepted. Mainstream scientific opinion on climate change is that warming over the last 50 years is caused primarily by the increased proportion of CO2 in the atmosphere caused by human activity. There is less agreement over the warming from 1850 to 1950.”
You tell me what forced LIA to stop and why you believe we’re not recovering still.
John Peter,
Careful on satellite measurements. We went 8 years with pretty much bupkes new for Earth observation, and what we have is not tailored to climate measurements. The experience of the UAH team is a good indication of the difficulties one can run into when turning satellite measurements into a climate “product”. And with the launch of the OCO (now dubbed the “Oceanic Carbon Observatory” by wags), there will be a deficit for a few more years.
There are a few birds going up that will have more ability to look in the IR. ICESAT2 is on the boards. OCO2 is under development. Global Precipitation Monitor is moving along, and the Solar Dynamics Observatory and other birds are looking at Mr. Sun. And it looks like DSCOVR might actually be allowed to look at Earth after all.
Even so, what is needed is a long-term, sustained program of observation using purpose-built satellites, and I don’t see that in the offing.
Ray’s pointer is the right place to look; don’t miss the following posting, also by John Mashey in the same thread, more specific to Akasofu’s paper. John did it as an exercise in how to work through a document and think about what you’re reading. Direct link, save for reference:
http://tamino.wordpress.com/2007/05/01/glaciers-al-gore-got-it-right/#comment-1754
This one (he gets up early):
“John Mashey // May 17, 2007 at 5:03 am
… http://www.iarc.uaf.edu/highlights/2007/akasofu_3_07/Earth_recovering_from_LIA.pdf
1) Thanks, I’ve seen this before, but maybe this worth going through as though I’d never seen it, as an illustration of skeptical analysis…..”
John Peter,
A rising temperature does not just happen. It requires a forcing? We know that increased insolation and decreased volcanism were occurring early in the century. We know that climate responds on a timescale of roughly a year (corresponding to the atmosphere and the shallow ocean) and has another relevant timescale of about 30 years. Given those timescales, what form would you expect the temperature rise to assume? Wouldn’t you expect a more rapid rise early on followed by a slow approach to a new equilibrium temperature? Yet that is not what we see. Instead, we see the most rapid rise in temperature in the past 3 decades. Why the delayed warming?
If you are going to posit a timescale substantially longer than 30 years, be careful. After all, Akasofu’s argument does nothing to invalidate all of the independent lines of evidence that show CO2 sensitivity is between 2 and 4.5 degrees per doubling. So if Akasofu is right, we are in fact further from equilibrium than we thought, and CO2 sensitivity must be on the high side of that confidence interval. Thus, we will warm more slowly, but the eventual damage will be worse.
Ultimately, Akasofu makes the mistake so many denialists make–focusing only on the temperature rise of the late 20th century. This forms only a tiny portion of the evidence that shows we are warming the planet. The evidence as a whole hangs together, and the only theory that comes close to explaining all of it is the consensus theory…which of course is why we have consensus.
> John Peter
> You tell me what forced LIA to stop
Stuff happens; no one event forced it to stop, it, er, petered out.
> and why you believe we’re not recovering still.
Multiple lines of evidence have been found showing a consistent change.
One paper mentioned at a NOAA paleoclimate page, for example:
http://www.sciencemag.org/cgi/content/full/295/5559/1511?ijkey=NyP8Qu6m/yT0E&keytype=ref&siteid=sci
Abrupt Decrease in Tropical Pacific Sea Surface Salinity at End of Little Ice Age, Science 295, 1511−1514 (2002)
Why might this be one good place to start reading? Because it’s been
Cited by 110 more recent papers.
Er make that second link
Cited by 110:
http://scholar.google.com/scholar?cites=6074965493478182875&hl=en&as_sdt=2000
John Peter
READ http://people.iarc.uaf.edu/~sakasofu/pdf/recommendation_to_postpone-shortened.pdf
Read his other Notes on Climate Change at http://people.iarc.uaf.edu/~sakasofu/the_big_steamy_age.php
Like this precious gem: “The most prominent warming (twice the global average) took place in the Arctic, particularly in the continental arctic, during the last half of the 20th century, as stated in the IPCC Report, but it disappeared during the last decade or so.”
There’s no science to argue. It’s garbage.
Re Septic Matthew – Yes, it’s not that G&T are not correct in pointing out that there are some complexities that can make a global average climate different than what it would be if all points on the globe were forced by global average forcings and then made to undergo the same responses (for one thing, that would obviate the coriolis effect, which varies over latitude), and with the added approximations of the surface as a perfect blackbody in LW, etc. But we already knew that. And it turns out the corrections for the global average surface temperature are not so big, but of course we need the whole globe and year, etc, to look at diurnal, seasonal, latitudinal, regional, transient and low-frequency variability – related effects in total and in response to changes (one can progress from a 1-dimensional time-average model to a 2-dimensional model (zonal average) to a 3-dimensional model, learning more and refining previous lessons each time, but the simple models help illustrate a portion of what is happenning in the more complex models and in reality.)) The Smith paper so far as I recall was not intended to describe a comprehensive climate model, but to merely illustrate how some of the laws of physics apply to climate (in particular, how the equilibrium average temperature changes if the temperature variation is changed), which is something G&T utterly screwed-up when they tried to apply the second law of thermodynamics and started refering to ‘superinsulation’, and apparent arguments which would seem to imply that nothing can ever actually emit any radiation – stuff that not only goes against established and uncontroversial physical theory and law, but even casual everyday experience combined with cause-and-effect logic (a photon emission can’t depend on conditions far away and in the future).
With regards to 2nd Law, the second law does not occur by way of a physical force (like gravity or electromagnetism) that attracts or repels energy. Rather, it works by default – it just happens because of statistics. Concievably (??), many if not nearly all hypothetical universes with all sorts of different physics would have to have a second law of thermodynamics (you could destroy entropy by creating a new physical law, but once that law is in place, entropy could no longer by destroyed).
Essentially, the second law is a consequence of the low probability of a system shifting into a ‘special’ state (a subset of possibilities that have a distinctly different ‘climate’) if it is not already in such a state. Entropy cannot be destroyed in net within a closed isolated system.
But in thermodynamic equilibrium, it is not the case that all processes shut down. Photons are emitted and absorbed and scattered, electrons and atoms and molecules gain and lose energy, chemical reactions occur, materials change phase, molecular collisions and diffusion transport internal energy and mass. But in equilibrium, all processes occur in forward and reverse directions equally. And even in disequilibrium, while one process may occur at a greater rate, the reverse can still happen.
G&T apparently must think ‘backradiation’ was made up to explain the greenhouse effect, but it is a consequence of established physics.
Re Septic Matthew by way of Re John E. Pearson 599
‘Greenhouse effect’ Is it a misnomer? I’m not sure it is. Of course an actual greenhouse works differently, as does a winter coat, from how the atmospheric greenhouse effect works, but they all follow a basic pattern: Energy goes in one way (solar radiation, metabolism, solar radiation again), is processed into a different form (generally gaining entropy) and it can’t all get out the same way it got in, and the way it can get out can be closed or open as if by a valve that can be largely independent of the valve that controls the energy inflow. So the energy can be forced to build up or be depleted to achieve equilibrium between inflow and outflow by adjusting the inflow valves (optical properties for SW radiation, metabolism) and the outflow valves (optical properties for LW radiation, thermal conductivity, convection) seperately.
Telegraph report on funding of climate change sceptics:
“An oil conglomerate (Koch Industries) has allegedly spent nearly $25 million on campaigns to discredit climate change and clean energy policies…between 2005 and 2008, according to a new report (Greenpeace).”
“…Koch Industries did not reject Greenpeace’s claims about its support for climate opposition groups but said its report “distorts the environmental record of our companies”.
Greenpeace…supplied a list of 35 organisations and 21 politicians – 17 Republicans and four Democrats – who it claimed received money, either directly or indirectly, from Koch or foundations it had set up.
“They include the Cato Institute, a conservative think-tank, and Americans for Prosperity, a free-market campaign group.”
http://www.telegraph.co.uk/earth/environment/climatechange/7538934/Oil-conglomerate-secretly-funds-climate-change-deniers.html
Hank, Ray, JiminMpls
Thanks for all your references to SA and his work. Collectively they make a powerful case for ignoring SA’s recent “climate research”. In particular, I found Mashey’s analysis creditable, fair and pretty complete. As Ben Santer might put it, the weight of the evidence is compelling.
Quite graciously and most fairly, youall have demonstrated that, while SA’s ideas might have appealed to me, any such appeal was more likely due to what I wanted to believe than to any intrinsic scientific merit in the ideas themselves.
Excellent work again. Thanks much.
Andreas (#613), re: reasons for disciplinary inclusion/exclusion in IPCC:
>I don´t have very much insight in the IPCC process
Me neither. So we’re trading speculations, and we’ve come as far as that will take us. You have a hypothesis, I have offered some alternative hypotheses. We won’t resolve this with general reflections on the disciplinary construction of research subjects. And we’ll bore others stiff.
If you have references regarding the stipulated disciplinary resistance you’ve heard or read about (against Russian historical approach, sustainable development approach, softies in general, etc.), I’ll read up.
Meanwhile, here’s an interesting article by a countrywoman of yours that indicates: some pragmatic, uncontroversial (?) ways anthropology could contribute to mitigation research; the importance of a gender approach; and – yes – a ‘soft’ scientist’s experience of techies questioning the relevance of her work.
Annette Henning, “Climate change and energy use: The role for anthropological research,” Anthropology Today 21, no. 3 (2005): 8-12. DOI: 10.1111/j.0268-540X.2005.00352.x
Does anyone by any chance know where I can find temperature data for some of the longest meteorological stations. I know that the central england station data can be received through the met office but I am trying to use a methodology similar to Jones and Bradley (1992) which looks at as many of the long records as possible. Cru and Giss don’t go as far back as the farthest datasets such as the ones from Trondheim (1761), Stockholm (1756), De Bilt (1706), Leningrad (1743), Berlin (1701), Cape Town (1857), Toronto (1770), Boston (1743), New Haven (1781), Rio de Janeiro (1832)… for example… I have tried the Global Historical Climate Network but haven’t been able to find what i’ve been looking for. Any ideas?
John Peter,
Glad we were able to help. You can certainly do worse than to consult what John Mashey has to say.
BTW, the first author on the execrable piece of crap that Septic Matthew has been flogging is Gerhard Kramm–one of the primary group of denialists around Akasofu. The denialosphere is indeed a very, small, small world.
John Peter (600)
Read my lips: Akasofu talks nonsense on climate science. He says the Arctic (!) isn’t warming. He says permafrost is melting due to the exhaust heat from buildings. He says carbon dioxide doesn’t influence climate. Good solar physicist. In climatology, he’s a loony. Period.
SM (615): How much of the 0.7C rise since 1850 is due to AGW?
BPL: Pretty much all of it.
629: Patrick 027 on “misnomer”.
Goody’s exact words (Atmospheres, 1971) which I quoted were “Some writers prefer to avoid this term because the analogy to the domestic greenhouse is not complete …”
I recall various atmospheric physicists saying similar things to me personally when I was an undergrad at Texas A&M. Perhaps “misnomer” isn’t the right word, but clearly enough the term isn’t an exact analogy and I presume that has been known since the first time the term “greenhouse effect” was used. To write 100 pages about it in the 21st century is pretty silly as is writing 10 or 15 more in defense of the 100!
“but clearly enough the term isn’t an exact analogy”
If the analogy were exact, it would be a tautology, surely?
602 Richard Ordway, Gavin
Jim Hansen pg 246, paragraph 2 is a statement of support for civil disobedience when we fail to do right through electoral processes.
Civil disobedience is a fine old American custom and is supported in the constitution’s bill of rights:
“Civil Disobedience is the act of disobeying a law on grounds of moral or political principle. It is an attempt to influence society to accept a dissenting point of view. Although it usually uses tactics of nonviolence, it is more than mere passive resistance since it often takes active forms such as illegal street demonstrations or peaceful occupations of premises. The classic treatise on this topic is Henry David Thoreau’s “On the Duty of Civil Disobedience,” which states that when a person’s conscience and the laws clash, that person must follow his or her conscience. The stress on personal conscience and on the need to act now rather than to wait for legal change are recurring elements in civil disobedience movements. The U.S. Bill of Rights asserts that the authority of a government is derived from the consent of the governed, and whenever any form of government becomes destructive, it is the right and duty of the people to alter or abolish it.”
http://www.civilliberties.org/sum98role.html
David B Benson & Ray Ladbury.
Concerning your citations of Tamino’s Volcanic Lull article:
End of PART 1…. full comment flagged for spam
Re “To write 100 pages about it in the 21st century is pretty silly as is writing 10 or 15 more in defense of the 100!”
Yes! I promise I won’t write any more than 9 pages on the subjet :) !
PART 2:
I’d like to move-on to Tamino’s second figure,
where he writes; The 30-yr smooth looks quite a bit different:
It is apparent that the value of zero at 1880 could only apply if there was zero volcanic forcing for at least the previous 30 years if PMA (Prior Moving Average) smoothing was used. (or 15 years if CMA was used). Perhaps this is true, however, in his replacing third figure he starts the x axis origin at 1900 ILO 1880, and writes:
We note that there’s a large decrease early in the data. This is not necessarily reflective of an actual decrease, it’s because for the earliest few decades we’re estimating a 30-yr smooth based on considerably less than 30 yrs. of data. To approximate the 30-yr smooth with any accuracy, we should only use the data from about 1900 on, giving us 30-yr smoothed values based on at least 20 years of data. That looks like this:
Testing: embedded link to tamino’s fig 2 removed
PART 3 This seems strange because whilst 20 years of real data is made available, (although hidden) it does not suit either PMA or CMA 30-year smoothing. There also seems to be a question as to what units are used, OR how the volcanic forcing can increase significantly when it is smoothed. Also, what weighting and why. Here is an approximate graphical comparison of unweighted PMA & CMA smoothing etc.
Here are the 1-year and 30-year smoothing graphs compared:
I’ve Emailed Tamino, asking for some clarification. Any thoughts?
Re John Peter: “Please keep up your radiation discussions.”…
Thank you; anything you had in mind?
(I’ve been thinking about trying to put something brief (enough for a couple comments) about atmospheric fluid dynamics together (Outline: enthalpy, kinetic energy, hydrostatic approximation, gravity waves, coriolis effect, geostrophic adjustment, momentum, potential vorticity, Rossby waves, wave-mean interaction) but that has a tendency to snowball…)
Patrick 027 @644
I appreciate your posts. They seemed pretty basic radiation balance to me. I’m a slow reader and you’ve already given me a week or two to digest.
I am trying to put together a table of radiation energy balance from Trenberth 2008 with ranges to try to get as simple an uncertainty build-up as possible. I would use your posts to cross check.
Since clouds are a key technical modeling problem a survey of what the models are really doing against what could be done should be of interest. Are any of the climate models 3D yet? What is the effect on the albedo? I’ve seen one paper on fractal clouds, are any models using them?
I’m very satisfied (and overwhelmed) with your topics to date so whatever you choose will be great by me. I only listed some suggestions because you have been so helpful I couldn’t turn down your request.
My advice would be to continue doing your own choices, they are great by me.
BobFJ (643) — I prefer decadal averages thus avoiding smoothing problems. Then the volcano forcings look to me to be appearing as part of AMO, so I prefer to use that, treating internal variability and the random volcano forcings together:
https://www.realclimate.org/index.php/archives/2010/03/unforced-variations-3/comment-page-12/#comment-168530
Robotic Planes Chase After Climate Data
http://www.technologyreview.com/computing/24907/?a=f
… Speaking of thermodynamics and solar power:
First, CORRECTION: I earlier wrote something to the effect of non-geometric optics being required to achieve the limiting concentration of solar radiation over a finite area; what I should have said was non-imaging optics are required (so far as I know); they can still be geometric (as in designed via ray-tracing, which is what I then did and will do here).
1. CSP with parabolic dish or trough reflector:
Earlier I gave equations describing concentration factor for a target that is a flat surface facing downward, crossing through the focus (relative to the dish or trough; upward (y) in this frame of reference is toward the sun, the direction across the trough or through the dish is x, and when it comes up, (0,0) is the focus).
In general, (describing the parabolic dish reflector; for a trough, the cross section through the trough and it’s targe is identical to a cross section through the axis of the dish and it’s target; conical surfaces become pairs of rectangular flat surfaces, a circular surface becomes a rectangular flat surface, a spherical surface becomes a cylindrical surface):
A parabolic dish with an aperture of radius a and length from center of dish to focal point r, with edges height h above the center:
g = a/r
G = 1/g – g/4
—————–
h/a = g/4
r/a = 1/g
(r-h)/a = 1/g – g/4 = G
r-h = a*G = the vertical distance from the edge of the dish to the focal point.
——————–
H is distance from edge of dish/trough to focal point
H = sqrt( a^2 + (a*G)^2 )
H/a = sqrt(1-G^2)
1/G = tan(b), where b is the angle from vertical for the reflected ray from the center of the sun off the edge of the dish; it is the angle from vertical of the line from the dish edge to the focal point.
————
q is the angular radius of the solar disk
sin(q) = Solar radius / distance from Earth to center of sun
————
A non-optimal but sufficient target that intercepts all reflected solar radiation is a sphere of radius Rts centered at the focal point:
Rts/H = sin(q)
Rts/a
= H/a * sin(q)
= sqrt(1-G^2) * sin(q)
—————-
A portion of the sphere does not recieve any reflected radiation; this is the portion within an angle J from the top of the sphere; this could be used to recieve direct solar rays, but excluding it:
Target Areas as a function of angle J:
area/length OF CYLINDRICAL TARGET:
= Rts * 2 * (pi – J)
= Rts * (2*pi – pi – 2*q + 2*b)
= Rts * (pi + 2*(b-q))
area of spherical target:
integral(j = 0 to J)[2*pi*sin(j)*dj] = 2*pi * [1 – cos(J)]
= Rts^2 * (4*pi – 2*pi*[1-cos(J)] )
= Rts^2 * 2*pi * ( 2 – 1 + cos(J) )
= Rts^2 * 2*pi * [ 1 + cos(J) ]
Other angles will be substituted in these formulas below.
—————
This is not yet a minimal area (for sufficiently small a, at least, including a = 2r, where G = 0).
—————
Consider angle JJ, the angle from the bottom of the sphere that is grazed by the lowest reflected ray off the dish edge:
ANGLES J and JJ:
(b-q) + J = pi/2
J = pi/2 + q – b
(b+q) + JJ = pi/2
JJ = pi/2 – (b+q)
—————–
Also consider an angle K on the sphere, from downward.
CASE 1 (perhaps (?) an optimal reduction of target area for intermediate aperture sizes; K will be different between the dish and trough cases and will be a function of G and q):
K is selected to minimize target surface area (K > JJ, if K is found to be only a little more than JJ, or smaller, then an alternative geometry is better (CASE 2).)
A flat circular surface of area Ab replaces the spherical surface within the angle JJ; this has radius Rts*sin(JJ)
The spherical surface above angle K is replaced by a conical surface, which is tangent to the sphere at K and extends upward just to reach the highest reflected ray. The radius of the lower edge is u and the radius of the upper edge is p. The area is Ac.
The remaining spherical area used is As.
—-
CASE 2 – a flat circular target area is used, with radius p, in the plane of the upper edge of the cone in CASE 1, where K = JJ. The edge of this target is at the intersection of the highest reflected ray from the edge of the dish on one side and the lowest reflected ray from edge of the dish on the opposite side.
———
Equations (I can’t guarantee that I didn’t make an algebraic error, especially here):
u = -xL = Rts*sin(K)
The position of the upper edge of the truncated cone, in cross section, is found at the intersection of these lines (both lines are tangent to the circular cross section of the sphere, the first runs through the conical surface, the second is a reflected ray from the edge of the dish, in a coordinate system with the origin at the focus, y upward, reflected ray coming from the negative x direction):
y + yL = -tan(K) * (x + xL)
y – yJ = tan(J) * (x + xJ)
where
L = pi/2 – K
xJ = -Rts*sin(J)
xL = -Rts*sin(K) = -Rts*cos(L)
yJ = Rts*cos(J)
yL = -Rts*sin(L) = -Rts*cos(K)
————
Solve for x:
yL + yJ = -x*[tan(J) + tan(K)] – tan(K)*xL – tan(J)*xJ
-x = [yL + yJ + xL*tan(K) + xJ*tan(J)]/[tan(J) + tan(K)]
p = -x
p/Rts = [-cos(K) + cos(J) – sin(K)*tan(K) – sin(J)*tan(J)]/[tan(J) + tan(K)]
————
Solve for y (y is the height (from the focus) of the top of the truncated conical surface):
y*[1/tan(J) + 1/tan(K)] = xJ – xL + yJ/tan(J) – yL/tan(K)
y = [ xJ – xL + yJ/tan(J) – yL/tan(K) ] / [1/tan(J) + 1/tan(K)]
y/Rts = [ -sin(J) + sin(K) + cos(J)/tan(J) + cos(K)/tan(K) ] / [1/tan(J) + 1/tan(K)]
———–
The length along the conical surface from top to bottom edges is Nc:
Nc = (y – yL) / sin(K)
u = Rts*sin(K)
CASE 1:
———————
The area of the conical surface is Ac:
Ac1
= pi*Nc*(u+p)
= pi * [y + Rts*cos(K)] * [Rts*sin(K) + p] / sin(K)
The corresponding area per unit length for a parabolic trough:
Ac2
= 2*Nc
= 2*[y + Rts*cos(K)] / sin(K)
————–
The area of the circular flat bottom is Ab:
Ab1 = pi*[Rts*sin(JJ)]^2
The corresponding area per unit length for a parabolic trough:
Ab2 = 2*Rts*sin(JJ)
————-
The area of the remaining spherical surface is As:
As1
= Rts^2 * 2*pi * ([1 + cos(J)] – [1 + cos(K)])
= Rts^2 * 2*pi * [cos(J) – cos(K)]
The corresponding area per unit length for a parabolic trough:
As2
= 2*Rts*(K-J)
————-
Target area
Atn = Acn + Abn + Asn, n = 1 or 2
————-
CASE 2: K = JJ
Area of target = An
dish: An1 = pi*p^2
trough, per unit length: An2 = 2*p
——-
Area (facing the sun, a flat projection) of dish or trough = Aan
dish: Aa1 = pi*a^2
trough, per unit length: Aa2 = 2*a
————-
Approximate concentration factor:
Cn’ = Aan/(Atn or An), n = 1 or 2
Exact concentration factor:
Cn = Cn’ – 1
for either n = 2
or n = 1 AND K < pi/2
otherwise
C1 = C1' – (a/p)^2
_______
Where
J = pi/2 + q – b
JJ = pi/2 – (b+q)
p/Rts = [-cos(K) + cos(J) – sin(K)*tan(K) – sin(J)*tan(J)]/[tan(J) + tan(K)]
y/Rts = [ -sin(J) + sin(K) + cos(J)/tan(J) + cos(K)/tan(K) ] / [1/tan(J) + 1/tan(K)]
u = Rts*sin(K)
——
g = a/r
G = 1/g – g/4
H/a = sqrt(1-G^2)
1/G = tan(b)
sin(q) = solar radius / distance to center of sun
————
Rts/a
= H/a * sin(q)
= sqrt(1-G^2) * sin(q)
—————-
And the limiting efficienty, relative to intercepted direct solar radiation, for perfect blackbody target (and perfect reflector, too!) is
(1 – Tc/Th) * [1 – (Th/Ts')^4 ]
where S = incident direct solar flux per unit area
and S*C = 5.67e-8 W/(m2 K4) * Ts'^4
Yes, I could tidy that up a bit (set a = 1 and then just deal with relative sizes, try solving for K (YIKES!), etc., but it's not like I'm getting paid here, so…
Anyway, it now occurs to me that the the target area for CASE 1 can be trimmed a bit more and still intercept all reflected rays (the radius of the circular area and the top of the conical surface and vertical positions of those must be the same, but the spherical and conical surfaces could be flattened a bit.
Note that the radiation emitted and absorbed by the target is limited by a minimum convex or flat surface that wraps around the actual surface; provided that the silhouette (sp?) of the target is not cut into as seen from any direction (no long grooves that wrap around a curve or penetrate to an edge), dents can be put into the surface to increase the effective absorptivity and emissivity of the convex/flat surface.
And the efficiency can be increased if the target is tightly wrapped in a greenhouse or otherwise has lower absorptivity at longer wavelengths, or if the target surface is not isothermal (with fluid coming through the cold parts first and exiting at the hottest parts – in which case, the target surface should probably pass through the actual focal point), etc.
In the partial surface area of a sphere, the line:
integral(j = 0 to J)[2*pi*sin(j)*dj] = 2*pi * [1 – cos(J)]
is not actually equal to the next line, but was work done in formulating the next line.
Sorry about the length; I was interested, I worked on it, I wanted to share, now I’m done with the geometric optics for CSP stuff. Hope this didn’t end the thread.
BPL@635
Strange. Have you looked at any of the other IARC research published in peer-reviewed climate science journals? That doesn’t seem to be what SA’s researchers publish, i.e. regional studies of ice and oceans using global models, etc.