This is the same Roger Pielke Snr who claimed a blog post/paper from denialist blogger Anthony Watts was a "game changer" - until it was pointed out by numerous sources (including hilariously named co-author Steve McIntyre) that Watts had not taken into account Time of Observation biases in the temp data. Then suddenly it was no longer a game changer. "Game Changer" for Pielke is a very low bar to jump over.

http://www.skepticalscience.com/watts_new_paper_critique.html

Thanks for thoughts Mike. and in the spirit of new evidence I'm glad you raised the Watts paper, but you must remember it has not gone through peer review yet, I'm sure the authors will take TOD adjustments into account and we'll see the effect on the trends once the paper is published. Perhaps you could provide Watts with your expert statistical analysis.
Now, I wonder if our BOM's Karl and Blair have considered the impact on BOM's ACORN analysis of the change in station classification criteria from Leroy 1999 to Leroy 2010 that is the basis for Watts Reanalysis of US station data. Watts et al find a warming trend but it seems that when stations are adjusted according to Leroy 2010 the trends are significantly lower than the NOAA who still use the older Leroy 1999 system.

Over to you Karl and Blair: does ACORN account for Leroy 2010? And what about the effects noted by McNider et al. Does ACORN account for those?

McNider, R. T., G.J. Steeneveld, B. Holtslag, R. Pielke Sr, S. Mackaro, A. Pour Biazar, J. T. Walters, U. S. Nair, and J. R. Christy (2012). Response and sensitivity of the nocturnal boundary layer over land to added longwave radiative forcing, J. Geophys. Res.,doi:10.1029/2012JD017578, in press.

Leroy, M., 2010: Siting Classification for Surface Observing Stations on Land, Climate, and Upper-air Observations JMA/WMO Workshop on Quality Management in Surface, Tokyo, Japan 27-30 July 2010http://www.jma.go.jp/jma/en/Activities/qmws_2010/CountryReport/CS202_Leroy.pdf

I'm not current with the temperature trend analyses and so it is a struggle to try to disentangle the blogosphere to'ing and fro'ing that has been quoted above.

From what I have seen, my understanding is that the Watts et al results are not in accord with the satellite data which supports the NASA, hadCRU and NCDC temperature analyses.

Nor does Watts analysis substantially alter the global trends, even if true it is US specific. It seems to be a case of grasping at straws.

Perhaps Karl and Blair can provide some insight!

Just delete your cookies and reload the page - you can vote as many times as you want - assuming you can be bothered.

What an insightful comment! Although my work was made a bit harder but those losers who go around clicking "unconstructive" on anyone that don't like regardless of content.

It would be easier if you automated the process
http://www.learnqtp.com/how-to-delete-cookies-through-a-script/
it probably wouldn't be hard to include an automatic voting script as well - never ever trust an online poll.....

I'm taking care to not vote on Mr Hendrickx's contributions to this page.

Their ludicrosities are self-evident; for example, BEST final results are problematic because they are not yet peer-reviewed, yet any old tosh from Pielke or Watts is to be gulped down post-haste.

DA, Up to your old tricks of throwing mud creating and battling strawmen!
I am happy to see how both WATTS and BEST pass through "pre" and normal peer review and whether either results in substantial contributions to the scientific debate. It appears that the effects of changes in classification from Leroy 1999 to Leroy 2010 on BEST, BOM and other temperature compilations is yet to be made, or perhaps you know different. Again perhaps Karl or Blair would like to comment, especially in regard to the BOM's ACORN data.

Mr Smith

You still haven't answered the ethical question I have posed to you many times:

How do you, as a person who fervently believes we should live a sustainable lifestyle in order to reduce global warming, ethically justify your own flying in the knowledge that this act consumes non renewable JetA1 fuel, and as such, is unsustainable.

Why don't you answer such a simple ethical question?

Gerard Dean

A deeper ethical question which you refuse to answer is this. How do you justify your pseudo-skepticism and continual pursuit of this third order issue (which is a tiny part of the overall sustainablility question and hardly pertinent to the challenges of climate change and for which offsets are available as an interim strategy - something you have not addressed with any evidence).

Deal with questions raised by Torcello or for goodness sake stop this repetitive off topic concern trolling

Torcello points out that actual skepticism is about positive inquiry and critical thinking, as well as proportioning one’s beliefs to the available evidence (not to mention being willing to alter those beliefs if and when the evidence changes significantly). You appear to practice none of these

Pseudoskepticism, on the contrary, makes a virtue of doubt per se, regardless of other considerations, and is therefore irrational.
he also says
(1) Ethical obligations of inquiry extend to every voting citizen insofar as citizens are bound together as a political body;
(2) It is morally condemnable to put forward unwarranted public assertions contrary to scientific consensus when such consensus is decisive for public policy and legislation;
(3) It is imperative upon educators, journalists, politicians and all those with greater access to the public forum to condemn, factually and ethically, pseudoskeptical assertions without equivocation.

Consider this deeper ethical question and stop boring us to death with your jet fuel side show

Dr Harrigan

Your claim that the use of hydrocarbon JetA1 fuel is a 'tiny part' of the overall sustainability and global warming question is laughable.

Air travellers burn over 340,000,000,000 litres of JetA1 fuel annually. That is three hundred and forty thousand million litres.

PseudoEnvironmentalism is a term I have coined to describe those who publicly profess to care for the environment and preach to others to do the same, then proceed to use enormous amounts of the earth's resources for their own air travel on holidays and academic conferences.

You might find it boring doctor, but old mother earth is bored as well, every day, for more oil, to keep you and Byron Smith in the air.

Just reminding everyone of the facts

Gerard Dean

Actually I think I do remember him answering your only ethical question.

Mr Dean

The emssions from jet travel are comparable on a per km travelled per individual basis to a single person travelling in a compact car.

Carbon emissions are surrounded by myths. It is widely believed that aviation is responsible for much of it. However it accounts for 1.6% of emissions.

Road transport accounts for 10% of our carbon footprint. Cars are responsible for the bulk of these emissions.

Just reminding you of the facts.

Your faux concern and posing of an "ethical dilemma" would be more convicing were it not so monomanically focused on a tiny issue on the pareto scheme of things

http://micpohling.wordpress.com/2007/05/08/math-how-much-co2-released-by-aeroplane/

http://www.carbonica.org/carbon-footprint/carbon-emissions.aspx

I shall watch with interest whether or not you accept BEST if it goes through peer review and repudiate Watt if it does not.

I don't think you understand the purpose or process of peer review.

Peer review works basically to eliminate obvious errors, it does not mean that the paper's conclusions are correct or even that the reviewers agree with the conclusions.

I don't think YOU Mr Lamb understand the process of Peer Review. Whilst every journal has a slightly different approach an essential element of any peer review process is that (1) the data are sound and (2) the results follow from the stated analysis of the data and (3) the conclusions are supported by the results

It is not a matter of "agreement". Peer review works to not only eliminate obvious errors but also to filter out poorly formulated analysis and results as well as conclusions unsupported by the results.

It is of course not a perfect process - but it is far superior to relying on blogs.

Please Sean, tell me you have something that you have put through peer review that I may then bow to your superior knowledge of the process.

Mark Harrigan: "... pseudo-skepticism and continual pursuit of this third order issue ...".
Mark, when your opponent demonstrates enthusiasm for shooting himself in the foot, is it wise to discourage him?

Didn't work that way with the recent paper by Gergis et al. It seems the peers did not review the data, didn't ensure that the results followed from the methodology and didn't check the conclusions. Yet this dead parrot of a paper made it though to "in press" and was embarrassingly withdrawn after a bunch of bloggers did the real job. Seems Mr Lamb has a better idea than YOU.

So Marc, let's look at the data here. If you want to go down the path of "well Gergis et at was withdrawn" then the logical conclusion (unless you want to cherry-pick an anecdote) to determine a ratio of peer-reviewed published climate science papers that have been withdrawn. One paper withdrawn does not represent a failure of climate science.

Ah yes, a single example makes the whole process corrupt doesn;t it Mr Hendrickx? Would that be cherry picking by any chance?

The Peer review process is not perfect - as i noted. My description however is how it is supposed to work - and on the avilable evidence DOES work most of the time. Of course it is no suprise that you would choose a single example that suits your case and then attempt to generalise from it - bit like your approach to climate science really.

http://www.experiment-resources.com/peer-review-process.html

http://undsci.berkeley.edu/article/howscienceworks_16

Of course the problem arises twhen there is PAL review

The main documated case of this was commiteed by climate science contrariansin the journal Climate Research from 1997 to 2003, during which time editor Chris de Freitas accepted 14 papers from a select group of contrarians. The journal had not published any papers from that group of authors previously, and only published 2 more papers from the group of 'pals' after de Freitas left.

http://www.skepticalscience.com/pal-review.htm

Strange that you chose NOT to draw attention to that????

"Far superior to relying on blogs" you say and once again you provide a link to that wet sponge: SS. LOL.

Dr Harrigan, I don't want to get in semantic argument about what peer review is or is not. Suffice to say we both agree that Mr Malleolus's apparent belief that if a paper passes peer review it is "correct." If only indutiably "correct" papers were published science would not progress very far or fast. The fact that science can accommodate so many papers that subsequently turn out to be "wrong" is the key to its robustness.

We may also be comparing apples and oranges here. I was referring to peer review as applied in sciences other than climate science. Rather infamously in the mid 2005 climate scientists decided secretly and unilaterally to change the definition of peer review - although they were rather red-faced when this was leaked. Fittingly it was this changing of the definition of peer review that helps us understand why climate science remains such a sickly specimen.

Errrr this:
"Suffice to say we both agree that Mr Malleolus's apparent belief that if a paper passes peer review it is "correct." "
is better written as
Suffice to say we both agree that Mr Malleolus's apparent belief that if a paper passes peer review it is "correct." does not reflect what peer review is about.

Sean - suffice to say Grendellus nowhere says he believes peer review is correct. If you actually follow this thread properly all he was doing was saying he would hold Mr Hendickx to task in applying the same standard of acceptance to the BEST review as he would apply to the WATTS paper in relation to their passage (or otherwise) through the peer review process. GIven Mr Hendrickx demonstrated inability to quote the science properly and tendency to jump on whatever suits his pseudo-skeptic views as valid and ignore anything else - thois seems a reasonable challenge. I note Mr Hendrickx has accepted it so we will wait and see

Also - what evidence do you have that Climate scientists "decided secretly and unilaterally to change the definition of peer review"? This seems an extraordinary claim and seems to lack an understanding of the process as it would imply that there is some "controlling" body that oversees the peer review process. Perhaps you are unaware that each journal runs it's own peer review process (thought it is usually similar across publishing houses)?? Your implication is that there is some "cabal" at work - this would appear to be labouring under the delusion of conspriacy theories

Marc - we get that you have a real problem with SKS. That fact that it has won an award for the way it presents published science and has a requirement that all posts reference published science that has been through peer review (usually multiple sources)- as well as forbidding ad-hom and personal attacks - something whihc you routinely engage in - no doubt means you are not welcome there. We understand.

It must hurt a lot that they are so well regarded and your poists are not

Happy to help - as always
http://www.guardian.co.uk/environment/2010/feb/09/peer-review-block-scientific-papers

Really Mr Lamb- you are trying to recycle the denialist myth of the so-called climate gate conspiracy as "evidence" of corruption of Peer Reveiw??? Is there no end to the tired recycling of discredtited rubbish fromthose who simply cannot accept the science of AGW?? Is there no lower bound to how low you will stoop to misrepresent??

There have been NINE separate inquiries on this. No conspriacy was found. Give it up
---------------------------
In February 2010, the Pennsylvania State University released an Inquiry Report that investigated any 'Climategate' emails involving Dr Michael Mann, a Professor of Penn State's Department of Meteorology. They found that "there exists no credible evidence that Dr. Mann had or has ever engaged in, or participated in, directly or indirectly, any actions with an intent to suppress or to falsify data". On "Mike's Nature trick", they concluded "The so-called “trick”1 was nothing more than a statistical method used to bring two or more different kinds of data sets together in a legitimate fashion by a technique that has been reviewed by a broad array of peers in the field."

In March 2010, the UK government's House of Commons Science and Technology Committee published a report finding that the criticisms of the Climate Research Unit (CRU) were misplaced and that CRU’s "Professor Jones’s actions were in line with common practice in the climate science community".

In April 2010, the University of East Anglia set up an international Scientific Assessment Panel, in consultation with the Royal Society and chaired by Professor Ron Oxburgh. The Report of the International Panel assessed the integrity of the research published by the CRU and found "no evidence of any deliberate scientific malpractice in any of the work of the Climatic Research Unit".

In June 2010, the Pennsylvania State University published their Final Investigation Report, determining "there is no substance to the allegation against Dr. Michael E. Mann".

In July 2010, the University of East Anglia published the Independent Climate Change Email Review report. They examined the emails to assess whether manipulation or suppression of data occurred and concluded that "The scientists’ rigor and honesty are not in doubt".

In July 2010, the US Environmental Protection Agency investigated the emails and "found this was simply a candid discussion of scientists working through issues that arise in compiling and presenting large complex data sets."

In September 2010, the UK Government responded to the House of Commons Science and Technology Committee report, chaired by Sir Muir Russell. On the issue of releasing data, they found "In the instance of the CRU, the scientists were not legally allowed to give out the data". On the issue of attempting to corrupt the peer-review process, they found "The evidence that we have seen does not suggest that Professor Jones was trying to subvert the peer review process. Academics should not be criticised for making informal comments on academic papers".

In February 2011, the Department of Commerce Inspector General conducted an independent review of the emails and found "no evidence in the CRU emails that NOAA inappropriately manipulated data".

In August 2011, the National Science Foundation concluded "Finding no research misconduct or other matter raised by the various regulations and laws discussed above, this case is closed".

"Professor Jones’s actions were in line with common practice in the climate science community".

Well, that was precisely the point I was trying to make.
I am a little perplexed you ask for evidence of climate science using different standards of peer review, I provided it.

I prefer the opinion of the Royal Society of Physics
"1. The Institute is concerned that, unless the disclosed e-mails are proved to be forgeries or adaptations, worrying implications arise for the integrity of scientific research in this field and for the credibility of the scientific method as practised in this context
....
2. The CRU e-mails as published on the internet provide prima facie evidence of determined and co-ordinated refusals to comply with honourable scientific traditions and freedom of information law. The principle that scientists should be willing to expose their ideas and results to independent testing and replication by others, which requires the open exchange of data, procedures and materials, is vital.
.....
6. There is also reason for concern at the intolerance to challenge displayed in the e-mails. This impedes the process of scientific ‘self correction’, which is vital to the integrity of the scientific process as a whole, and not just to the research itself. In that context, those CRU e-mails relating to the peer-review process suggest a need for a review of its adequacy and objectivity as practised in this field and its potential vulnerability to bias or manipulation."

We each pick the data set we like the best, you like your 9 enquiries, I prefer to defer to the tradition and authority of the Royal Society of Physics.

Each to his own, Dr Harrigan.

On a personal note, I find it puzzling to understand how anyone who really cares about science, over and above the petty squabble about AGW, could fail to be disturbed by the content of those emails. AGW could be splendid and those emails were still unseemly. Indeed, if the foundations are so secure, squalid behind the scenes politiking should be unnecessary.

One is reminded of Adam Smith:
“People of the same trade seldom meet together, even for merriment and diversion, but the conversation ends in a conspiracy against the public, or in some contrivance to raise prices.”

Great Sean, I agree to defer to the Royal Society too - so I note you must also endorse their statement

http://royalsociety.org/climate-change-summary-of-science/

"There is strong evidence that the warming of the Earth over the last half-century has been caused largely by human activity, such as the burning of fossil fuels and changes in land use, including agriculture and deforestation. The size of future temperature increases and other aspects of climate change, especially at the regional scale, are still subject to uncertainty. Nevertheless, the risks associated with some of these changes are substantial."

Glad to know you have renounced your denial of the fact there is a problem to be addressed :)

Lord love a duck, Dr Harrigan are you really sure you have an aptitude for science at all?

What next? Are you going to trot out PWNED!!!! LOL!!!?

You are a perfect exempar of Prof Greenfield's warning on the baleful effects of the internet on human cognition.

Ah Sean - reduced to personal denigration now that you have been caught out? Perhaps you shoulld also examine prof Greenfield's evidence for her claims - they are lacking

I understand Lysenko was also awarded many prizes for his work in presenting the published science.

You really need to heed your own advice. The scientists know, the problem is that it's you who don't know. It's a common problem these days. "If I can't understand it, you can't prove it to me".

Sean,

The BEST study has confirmed that historical temperature MEASUREMENTS are valid. That is, denial of warming trends is denial of reality, nothing more, nothing less.

Mueller et al's attribution exercise is an afterthought and has already been done to much greater depth by other researchers.

The remainder of your contribution reads as sophistry in retreat, so here's a clarification to help you retreat.

Earth is warmed by absorption of short wave sunlight. Because of this, Earth's temperature can remain unchanged by returning the same amount of energy to space. That is, solar shortwave energy is balanced by the earth re-radiating to space as a 'black body' radiator with a characteristic temperature of ~255K; that is, from space the earth's spectrum is roughly that of a radiating body with an optical surface temperature of around 255K.

Earth's surface cools by evaporation of excited water molecules, heat transfer to deeper sea and to polar ice caps and by convection and radiation back into and through the atmosphere. At higher altitudes, where the atmosphere gets less dense, the proportion of energy (heat) transfer by long wave 'thermal' (microwave) radiation increases. Observing earth's spectrum from space has big absorption bands due to greenhouse gases in the upper atmosphere. Prominent among these is carbon dioxide (CO2).

Greenhouse gases such as H2O, CO2, methane (CH4), nitrous oxide (N2O), CFC's, and ozone (O3) absorp, then re-emit, some longwave wavelengths. About half of the re-emitted radiation is diverted back down toward the surface, as confirmed by radiation measurements at both surface and satellite observatories. This discrepancy increases with atmospheric CO2 concentration.

Well perhaps if you say it enough times it will turn out to be true?
Magical thinking in humans never ceases to fascinate me.

"The BEST study has confirmed that historical temperature MEASUREMENTS are valid. That is, denial of warming trends is denial of reality, nothing more, nothing less."

Two problems:
1. You don't under the scientific process, since no study ever provides indisputable confirmation of anything.
2. You mysteriously didn't seem to understand what I wrote - which I find troubling as I dumbed it down to make it intelligible even to those without science training. To make it clear I am agnostic to the degree the earth has been warming. I assume it has been to some extent, I also assume that a portion of that warming is due to greenhouse gases - but I don't hold firm opinions. My experience is that human frailty makes the scientific method a very fragile tool in the face of human politics and these trends are likely to be overstated. But this was not the point I was making, rather it was a broader point about scientific induction.
A pity it went over your head.

Even if you are not convinced of the science - you have to ask yourself:
What do we do in the absence of certainty? Minimize risk.

Do be honest, I don't care what you do. I am only interested in the science aspects and the way science and the public sphere interacts.

As far as I can tell no one is really making a serious plan to imagine a world with radically decreased carbon emissions, instead some push their own personal blue sky research agendas, others concentrate on making convoluted financial instruments which are seen as an end in themselves. So I assume at an elite level everyone is as blase about the threat as I am.

Which is cool, everyone should pursue that which interests them. I am interested in the science and science politics.
Fair is fair, I grew up worrying about nuclear war, I don't see why today's generation of youth shouldn't have their own existential fear bubbling away in the background for them to wax idealistic about

Sean Lamb: "... I assume ... everyone is as blase about the threat as I am."
Or not: http://thinkprogress.org/climate/2012/08/04/640391/must-read-hansen-climate-change-is-here-and-worse-than-we-thought/
Those who conquer their fears, we might call heroes. When fear is warranted, what might we call those who prove too dull to fear?

Berthold - you obviously must have missed the science I have been patiently trying to explain to you - or are just deliberately fudging?

I'll repeat (I can sue copy and paste too old boy)

https://theconversation.edu.au/climate-change-and-the-soothing-message-of-luke-warmism-8445

Berthold - I'm afraid you lack some basic understanding. Treating the earth as a grey body would mean the surface temperature would be LOWER than the black body calculation shows ans hence the Greenhouse effect would have to be STRONGER.
So you still have not offered a plausible and sound according to the laws of physics reason why (a) the temperature of thre planet is much higher that it would be without the GH effect and (b) an explanation for the measured spectrum at the surface and TOA consistent with GHG absorbtion and back radiation
It's true the Earth is not a perfect blackbody. That means it does not perfectly absorb all the radiation from the sun There are a few ways to deal with this. One is to treat it as a blackbody (as I have done) but reduce the amount of incoming energy in the equation to allow for the radiation that is reflected (a perfect black body would absorb all the radiation). The other is to adust the euqation for the imperfect emissivity (a value between zero and 1).
Both ways would result in a lower temperature than the perfect black body equation.
There's a relatively simple explanation here http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law under the section "Temperature of the Earth"
For the difference between a black ody and a grey body look here
http://www.irblackbody.com/emissivity.php

It is all a bit beside the point - obvious the Earth isn't a blackbody - but any attempt to purely physical first principles to model the Greenhouse effect are doomed to failure.
As Swan and Flanders would have put it: "you can try it if you like, but you far better notta" (Don't go forgetting that convection, Dr Harrigan).
A model will have to be derived empirically first and then first priniciple calculations will need to fitted to those empirical calculations.

As always, happy to help.

Well Sean, since you are SO helpful and you are obviously having trouble understanding that GH effect is real I'll provide the more comprehensive explanation - which includes convection.

Don't go forgetting that commitment to agreeing with the Royal Society now will you :)

The experimental evidence for the Green House effect is here
http://www.skepticalscience.com/images/infrared_spectrum.jpg
Allow me to explain
A few facts are in order
1) A real green house on the earth works differently to the (badly named) Green House effect - although the outcomes are similar - both trap heat
2) It is an experimental fact that polyatomic gas molecules (like H2O and CO2) absorb IR radiation whereas diatomic molecules (O2 and N2 - the bulk of the atmosphere) do not. Molecules that absorb IR will re-emit the absorbed radiation within a period of time after they absorb it (unless they lose the additional energy acquired by a collisions before they can re-emit) - even Berthold has managed to parrot the facts on this.
3) It is also an experimental fact that all matter will emit radiation when above absolute zero. It does so according to Kirchhoff's Black body radiation emission spectrum which is a function of its temperature. The respective "Black Body" curves of the Sun and the Earth are shown here (not much overlap) http://marine.rutgers.edu/mrs/education/class/josh/images/bbes.gif
4) Molecules that absorb IR will either (a) share that energy with other molecules they collide with if the average time between collisions is much less than the re-emission time or (b) radiate it away isotropically if the mean decay time is less than the collision time
5) The earth is warmed by incoming solar radiation (around 341-342 Watts per square meter Wm-2 or 341 Joules per square meter per second).
Some of the 341Wm-2 is reflected by the atmosphere and the surface (102 Wm-2 about 30%) leaving 239Wm-2. If that were the end of the story we can calculate using the Stefan Boltzmann law that the earth's temperature would be (assuming no GHGs) about 255K or minus 18 degrees centigrade. Hardly liveable. But it is actually around 15 degrees C so SOMETHING else must be happening!
Of the 239Wm-2 the planet absorbs from the sun some is absorbed by the atmosphere (78 Wm-2 about 23% of the incoming) and the rest (161Wm-2 about 47%) is absorbed by the surface.
6) The surface also absorbs any radiation that is emitted by the atmosphere (either directly or as back radiation - about 333Wm-2). The energy absorbed by the surface (161+333=494 Wm-2) must be re-emitted to maintain a (globally averaged) constant temperature. Around 20%(97 Wm-2) is transmitted to the atmosphere by evaporation and direct thermal conductivity. 80% (397Wm-2) is radiated away of which around 10% (40Wm-2) goes straight through the atmosphere and the rest is absorbed by GHGs (357Wm-2).
7) The atmosphere therefore has a total 78+97+356=531Wm-2 in it - 199Wm-2 is radiated away at TOA (top of atmosphere)(plus the 40Wm-2 that goes straight through the atmosphere to give a total of 239Wm-2 radiated away) and 333Wm-2 is re-radiated back toward the surface (all the above figures are from the measured earth energy budget in early 2000's - see Kiehl & Trenberth 2009.)
Now - here's where it gets a bit subtle and why the "experiments" Mr Klein talk about prove nothing (other than that a greenhouse works differently from the "Greenhouse Effect").
In the lower atmosphere, where the mean time between collisions of molecules is MUCH shorter than the mean decay time of an excited GHG, most of the IR absorbed by GHGs is lost to the rest of the atmosphere (O2 and N2) by collisions - contributing to "heating" the air. BUT, as you go up to TOA where the air is much thinner (so fewer molecules) the mean time between collisions is much LONGER than the mean decay time of a GHG which has absorbed IR so most GHGs lose their energy by radiation, around half of which is directed back toward the earth - heating the "layer" of the atmosphere lower down and so raising its blackbody temperature
This can be seen and measured by satellites as radiation escaping the planet and hitting the earth. What's of interest to us is the radiation in the IR spectrum since IF the greenhouse effect exists we would expect to see something.
The absorption by GHG's takes a "bite" out of the blackbody spectrum emitted by the earth. In turn the radiation being received by the earth (from the atmosphere) has a peak in it. These peaks correspond PRECISELY to the absorption and emission frequencies/wavelengths of GHGs.
THE EXPERIMENTAL EVIDENCE FOR THE EXISTENCE OF THE GREENHOUSE EFFECT IS THUS SHOWN HERE AS MEASURED BY SATELLITE
http://www.skepticalscience.com/images/infrared_spectrum.jpg
Have a look at the graphs. You can clearly see the lost radiation from the blackbody curve being emitted at TOA CORRESPONDING THE REDUCED IR ESCAPING TO SPACE.
You can also clearly see the increase in IR received at the earth. CORRESPONDING TO EXTRA ENERGY REATIED BY THE PLANET DUE TO GHGS
hence the planet is some 33 degrees warmer (average) than it would be without the Green House effect.

THIS is the experimental evidence for the Green House effect and NO CREDIBLE SCIENTIST OR PHYSICIST DISPUTES THIS
If you'd like to read a more technical description go here
http://geosci.uchicago.edu/~rtp1/papers/PhysTodayRT2011.pdf
"The CO2 greenhouse effect is directly visible in satellite observations of the "bite" taken out of the IR spectrum near 667cm-1, a feature whose detail s agree precisely with results of calculations based on first-principles radiative transfer calculations. Laboratory spectroscopy demonstrates that the width of the bite will increase as CO2 increases, and warming inevitably follows as a consequence of well established energy balance principles. The precise magnitude of the resulting warming depends on the fairly well known amount of amplification by water vapor feedbacks and on the less known amount of cloud feedback. There are indeed uncertainties in the magnitude and impact of anthropogenic global warming, but the basic radiative physics of the anthropogenic greenhouse effect is unassailable"
For a little less complex there's NASA
http://climate.nasa.gov/causes/
And for a simple explanation on video (from the National Academy of Sciences) go here
http://www.youtube.com/watch?v=3JX-ioSmNW8&feature=player_embedded

All of the evidence for AGW is summarised neatly here
http://www.skepticalscience.com/How-we-know-were-causing-global-warming-in-single-graphic.html

Thank you Dr Harrigan I am well aware of what the Greenhouse effect is. Nor do I dispute that it exists, I merely quibble on the magnitude.

I am also pointing out that a first principles approach, as you appeared to advocate will almost certainly not match empirical observations - particularly if you don't comprehend all the significant factors.

Speaking of which do let me know when you have come up with an explanation for the correlation of sun spot number and warming on earth - won't you?

If this causes you any difficulty, can I suggest you do what I always do when dealing with a particular knotty problem? Slip a disc of Grease into the CD player and cogitate
http://www.youtube.com/watch?v=wK63eUyk-iM
Try it, It works wonders, I promise you.

That's terrific Sean. I am in awe of someone who presumes to know more than every single national science body of credibility who has reviewed the data with dilgence and have come to a quite different conclusion.

One can only wonder at the intellectual capability of someone who with no more than an armchair from which to analyse can somehow obtain evidence and reach conclusions that the rest of us mere mortals - not to mention the many thousands of practising scientists who actually spend their lives studying the subject - have failed to do.

I take my hat off to you. No doubt it's the grease you are applying to your, er, intellect.

Tell us all - please - how do you do it?? the world wants to know

(that's assuming what you are doing with the Grease is able to be shared in polite society of course?)

Sean

"A model will have to be derived empirically first and then first priniciple calculations will need to fitted to those empirical calculations."

You mean like Radiative Transfer Codes (RTC), programs that apply the theoretical understanding of radiative heat transfer in the air based on the Radiative Transfer Eqn to data on the radiative properties of a range of gases, their variations in concentration with altitude and the vertical distribution of temperatures, all based on empirical observations.

The RTC's then allow us to calculate the expected radiation spectrum one would see at different altitudes, looking up or down, for different locations and times of year.

We can then compare the calculations, based on theory and data, against the actual observations. Where we observe phenomenal agreement between theory and observation.

Is that the sort of thing you mean? Because that is actually what has been done. Decades ago. From the late 1960's onwards.

That is a problem many skeptics have. They come to considering this issue decades after the scientists first started looking at it. Then ask questions, some of them reasonable, many others just foolish, but being posed decades late.

It's like they heard about a party, show up expecting a party that they might join, and discover that the party is over. Obviously there was a party but the skeptics came to it after it was over.

Before posing all sorts of questions, perhaps you need to acquaint yourself with the existing science. Suggested starting points. Revell in 1938 solving CO2 absorption by the ocean. Mid 50's, Goody's formulation of the Radiative Transfer Eqn, Gilbert Plass's first exploration of the physics of the GH Effect in 1956. Move forward from there to the late 70's and you will have the basis of the thermodynamics of climate science. All while I was in primary and high school.