Nine oncologists tell you you need urgent surgery to remove a tumour, but the tenth says it's benign, so why spend all that money on intervention? Good luck mate.

The ulcer analogy is more awkward because in that case there clearly was a problem; the debate surrounded the cure. If Spencer and his small counter-consensus band are right, there isn't even a problem. Besides, the conventional treatment was better than doing nothing, taking antibiotics as well would have been a simple and safe hedging of the bet, and there was no great urgency in getting it right. The cancer analogy is much closer.

You're entitled to your conspiracy theory views of the scientific establishment, but don't underestimate the temptation to be a scientific maverick. Plenty of distinguished scientists have espoused views that were ridiculed then and are ridiculed now: Newton, Hoyle, Kelvin, Gold, ....

The "only experience being in the lab" gibe is a little off target. Spencer depends as much on models as anyone else.

Bear in mind I'm not advocating dismissing Spencer. I'm glad there are people like him questioning and probing orthodoxy. (Just a pity he doesn't do more pointing out the foolishness of Monckton and the like.) But until his views become consensus it would be crazy to bet the farm on his being right. When it comes to policy, it isn't a question of proof beyond reasonable doubt, it's a matter of risk management.
If you had been an ulcer patient when Warren and Marshall first published, would you have immediately given away the conventional treatment and depended solely on their work?

9 out of 10 climate change skeptics are geologists - I just made that up, however geologist are over represented. Most likely because there industry is heavily invested in fossil fuels. Do you realise your position is predictable ?

Your metaphor of nine in the same lab, is so far from the truth it is useless. Most scientists employed in climate change are funded from disparate sources and often dependent on grants, where as almost scientists employed by industry are employed by a relatively small number of cashed up international resource companies.

This seems to be a standard climate denial miss-direction - accuse those who disagree with you of the very crime you are guilty of.

Your story of Helicobacter only provides an example of a case where the received wisdom is subsequently proven incorrect. So what, it has no cause and effect relationship to what 97% of peer reviewed science is telling us. Once replicated and peer reviewed the existence of Helicobacter had to be accepted. So why are you not accepting the Enhanced Green house effect ?

I would like to see the research but I expect the diversity in funding sources of the climate change skeptics is far less than the protagonists.

What is "peer reviewed press" ? don't most of us class the press (the conversation excepted) as less trust worthy than new car salesmen ? 10 out of 10 used car salesmen say the car will not break down in the first year after purchase.

At one of your links Smith's critique of Spencer's 2 step formula to measure climate sensitivity is itself predicated on a demonstrably false assumption; which is perturbations in the climate system do not restore to or around an equilibrium but instead create tipping points which by virtue of the forcing formula used by the IPCC produce a runaway scenario, which the author of this article supports. By comparison Spencer and Braswell’s formula is supported by the climate history of this planet.

I have noted this before on another thread; The IPCC attributes ACO2 [CO2 from human emissions] as being the forcing agent, F, for the 2XCO2 = 3C scenario, with water vapor the feedback, f, and temperature, t, the parameter for the change; the interaction of these variables is measured by the state vector, S, which would itself change if F has the effect the IPCC alleges. IPCC represents this dynamic thus:

dS/dt=S/f+F

IPCC assumes that f is +ve so if we integrate by dividing both sides by fS+F, and multipling both sides by f*dt we get:

(S2+F/f)/(S1+F/f)=exp(f*(t2-t1))

The problem with this is because it predicts that as the final value of t, t2, approaches infinity, the value of S2 becomes infinite. This is wrong because if there is a climate forcing in operation, at infinite time, the temperature anomaly should approach its finite equilibrium value even if there is positive feedback.

In layman's term you can't have it both ways; either the IPPC forcing formula is correct and there is no limit to the temperature response, that is, the runaway condition is extant, as Hansen has concluded, or there are constraints.

In respect of those constraints Spencer and Braswell have looked at the issue of boundary conditions to forcing from ACO2:

http://www.drroyspencer.com/Spencer-and-Braswell-08.pdf

Their equation 2 is:

Cp*T/*t=-^T+N+f+S

The difference with S&B’s equation is that it introduces a term for the stochastic properties of clouds, N and breaks F into -^T and f; f is ACO2 and -^T is a total feedback term which must be negative so that an infinite equilibrium is impossible. S&B ran their equation using observed variations in radiative flux related to random cloud movements; their model is therefore much more realistic than the IPCC’s formula which is limited to temperature and ACO2 forcing. S&B found that in the real world, even assuming a +ve forcing from ACO2, climate sensitivity and feedback were much smaller than that relied on for AGW. Given this a tipping point based on ACO2 forcing is not possible.

S&B 08, an encyclopedia of errors. Yawn.....

http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI3657.1

for starters.

How you can still accept these papers, which have been debunked, and at the same time ignore ALL of the thousands of research papers, with hundreds and hundreds of different lines of proxy and empirical evidence from ALL walks of science that have been reviewed and agree with AGW is staggering.

You ignore advice and research from EVERY scientific body of national and international standing IN THE WORLD. You are obviously are a very smart person, much smarter than myself but if you do want to be taken as a genuinely sceptical person (who are needed), and not a denialist with alterior motives, may i suggest dropping the disproven science when it is disproven and divorcing yourself from Mr Monckton, neither do you any favours at all.

Spencer and Braswell have replied to Murphy and Foster:

http://www.drroyspencer.com/2010/07/can-climate-feedbacks-be-diagnosed-from-satellite-data-comments-on-the-murphy-forster-2010-critique-of-spencer-braswell-2008/#comments

Did you even consider my point about the comparison between Spencer's model of climate sensitivity and the formal AGW one; how do you explain the narrow temperature range of this planet throughout its history despite forcings adequate enough to instigate runaway according to AGW theory?

If you can't explain then ask the author of this article to explain that glaring inconsistency since he is an avowed catastrophist.

Anthony that link just seems like Spencer having his usual whinge about the peer review process and how it conspires against him (when he is not praising it for publishing his papers) and using it as excuse to sidestep it with what is mentioned therein.

Some of the usual errors and refusal to change equations that have been proven incorrect.

Think I will let Spencer himself sum up on it...

Steve Fitzpatrick writes....

"My goodness, this data just looks like noise!"

Roy W. Spencer, Ph. D. replies......

"I cannot disagree. But I still have to try"

Have no problem with people trying, it is very commendable (not being patronising, it really is) but they just loose all cred when just refuse to admit they have not got it right and take critisisms personally. He is just wrong (so far), thats all, nothing personal.

In relation to your question, I have a pretty simple answer. Humans. Thats the biggest explanation. Humans disrupting the natural cycles of The Earth. It has taken the natural world millenia to store carbon and we are releasing it in a geological nanosecond. It is inconcievable that this would have no effect on The Earths complex systems and by extension the general stability of temperatures that can support life. I believe we are just only starting to understand some of these systems sensitivities and the effects of human activity on them. Our knowledge will get better, aided by the Spencers of the world in a way, but just too many scientists and our most trusted institutions seem certain the more we find out the worse it will get not better, and that we are the biggest culprit.

Just one question for you Anthony, and I could be mistaken but, isnt arguing for very low climate sensitivity at the same time as arguing the MWP was warmer than studies using a higher sensitivity suggest just a little bit oxymoronic? Actually is it even oxy?

Not wanting to slap any pies at journals Marc but this work by Spencer started out being published in a very prestigious journal. Since then errors have come to light, even pointed out by some of the original reviewers, and Spencer yes has corrected some of those but is still sticking to some pretty flawed models and equations. This is accentuated by the fact he is publishing in a journal of far less reputation. It is ranked 9th just in the Remote Sensing field. Is not a pie slap, but a fact. Did he not try 1-8? Did it get knocked back? If this work was truely groundbreaking and packed with new evidence disproving the case for AGW i'm sure he could have had it published wherever he chose. Time will tell us the absolute validity of the paper but there is one indicator that suggests it is again flawed, Douglas Cotton agrees with it entirely ;-)

I have referred to irony before Nick; Spencer is known for his ironic comments.

I was rather hoping Derek would respond to the point about the issue of regression for cloud imput against temperature given the stochastic properties of clouds and their role as both feedback and forcings.

Nonetheless your point about relative sensitivities to do with the MWP and current temperatures is not germane for 2 reasons.

Firstly the IPCC official position is that even if something other than AGW caused the MWP, which must be the case, that does not mean that AGW is not causing the current temperature increase. Of course this can work both ways; that is what caused the MWP is also causing the current temperature increase and the increase in CO2 is either irrelevant or is having its effect swamped by natural process. In fact the new Loehle and Scafetta argues this very point:

http://benthamscience.com/open/toascj/articles/V005/74TOASCJ.pdf

The point here is that the climate sensitivity to extra CO2 is low but to small variations in TSI, high. Not really a difficult concept and confirmed by Glassman:

http://www.rocketscientistsjournal.com/2010/03/sgw.html

I agree that humans impact on the environment but not through CO2 and that predictions of even worse scenarios are just agitprop; in fact as your good friend Lord Monckton notes the dire predictions are either getting worse or declining, can't you make up your mind:

http://scienceandpublicpolicy.org/images/stories/papers/originals/gore_testimony.pdf

Funny, I have found a journals ranking to rest heavily on their citation record.

Turns out we didnt have to wait long...

http://thinkprogress.org/romm/2011/07/29/282584/climate-scienists-debunk-latest-bunk-by-denier-roy-spencer/?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+climateprogress%2FlCrX+%28Climate+Progress%29

This is just the latest in a long line of experts testing S&B's theories and trying to reproduce their results.

Your "best tests of science" criteria seem to constantly debunk the alternate theories for explaining the temperature trend. Some papers have seemed absolutely acceptable and plausable but have, unfortunately for us, been disproven. In Spencers case ad nauseum.

As for the current theory of dangerous climate change driven by anthropogenic carbon dioxide emissions, the only genuine scientific grey area to that theory is just how bad it will be, not 'is it happening at all?'.

Anyone who doubts it hasnt passed enough tests should really read this with an open mind to help decide what is most likely.....

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

Marc, is this acceptable as genuine scientific position, formed with the best knowledge we have, or is this massive convergance of opinion from all walks of science just an elaborate conspiracy facilitated by the scientific journals to hurt Spencers, Lindzens et als feelings? They sound similar to a footy team whinging about a different umpire every week whilst getting comprehensibly beaten. The only games they win are when they invite one of their biggest fans, like SPPI for an example, or maybe The Heartland Institute, to umpire the game.

If nothing will touch your views unless it is a "considered reply...... in the journal in question" why keep asking for The Con to comment? You bored? Need something to argue about? You know as well as I do if they did do a commentary it would be from a person with relevant expertise and would probably take Spencer apart (again) like the experts have already started doing (again). You say Im joking giving you a link that contains critques from world renown experts and yet you want "commentary" from The Con. Try reading the link i posted, it is better than commentary, it is the start of a major critique (again).

It is It is certainly not Joe Romm that gives this post any cred. After all in it he is just collating info, similar to Mr Watts, Mr Cook and others. I do though however take NASA climatologists and the words of NOAA cloud researchers a little more seriously. These guys are experts in the field not bloggers like you, me and Romm. Their initial evaluations are very damning and one thing I am sure of is that they arent joking. If you are actually sceptical these comments (did you actually read or just see 'Climate Progress' and ignore?)from experts in relevant fields must create some serious doubt in your mind.This continues a trend for Spencer I am afraid, which is likely (again) to end up in some awful peer reviewed peer reviews. In any case they will be a waste of time (again) as Spencer denies even there is proof of macroevolution let alone AGW so he obviously has a hard time with facts. You seem maybe sceptical but stack the deck against AGW, so both of you will have no trouble ignoring any evidence he is wrong (again) and just shift the goalposts and move on or just blame it all on conspiracy theories and bias from those in the ivory tower.

It is apparent Nick, that contrary to what you first told me that nothing will change your mind about AGW being real. You link to Romm's site, who is a joke, and the same old AGW warriors, Trenberth, Dessler etc. I couldn't even get past Dessler's first paragraph which contains an egregious error; Dessler says this:

"As the planet warms, you get more water vapor in the atmosphere, and since water vapor is itself a greenhouse gas, this leads to additional warming."

In Franks recent paper the error of assuming higher temperatures will increase evaporation is discussed:

http://www.agu.org/pubs/crossref/2009/2009GL040598.shtml

Franks makes it plain here:

http://www.australianclimatemadness.com/2009/11/shock-murray-darling-warming-not-due-to-co2/

I am at a loss to explain why supposedly clever people are in thrall to the poppycock presented as 'real' science by the leading lights of AGW science [sic]; but I don't want to get psychological in case leading AGW expert Lewandowsky chimes in.

Franks' paper explains that if an area is in drought that will lead to higher temperatures right there. So the observed higher temperatures did not necessarily cause the drought. I've no problem with that.
It would be quite wrong to go from there to saying higher temperatures will not increase evaporation, and in particular where there is no lack of water, such as over oceans and lakes.
We all know warmer air can and does hold more water vapour. It is utterly ridiculous to declare Dessler's statement an "egregious error". Lose 10 credibility points.

Derek, I'll stick with egregious thank you; for a number of reasons; firstly Franks' effect is not regional; it is common to any area of land. This dovetails with well documented findings of decreases in pan evaporation over land during the past 'warming' period:

http://www.rsbs.anu.edu.au/Profiles/Graham_Farquhar/documents/271RodericketalPanreviewIGeogCompass2009_000.pdf

Roderick et al conclude:

"Analyses of the pan evaporation data averaged over many pans from
many different countries has revealed declines that are typically in the range
of −1 to −4 mm a−2 (Table 1). In energetic terms, a trend of say −2 mm a−2
is equivalent to −0.16 W m−2 a−1. For comparison, estimates of the top of
the atmosphere radiative forcing over the last 40 years are an order of
magnitude lower at about 0.02 W m−2 a−1 (Hansen et al. 2005). Clearly,
the pan evaporation trend is large, and combined with the fact that it has,
on average, declined, warrants further and detailed investigation."

Dessler dismisses this.

Dessler also is at the forefront of the view that levels of WV are increasing in the atmosphere; he has a 'vested interest', so to speak, in hiding behind the The Clausius-Clapeyron relation which shows how the water-holding capacity of the atmosphere increases by about 8% per degree Celsius increase in temperature. The point about this is that it increases the CAPACITY; whether it actually does increase the SH depends, amongst other things, a constant RH. A constant RH has been assumed by AGW theory but no definitive proof of that has been presented.

What has been presented is evidence of declines in SH:

The Soloman paper:

http://www.sciencemag.org/content/327/5970/1219.abstract

The Paltridge paper:

http://www.theclimatescam.se/wp-content/uploads/2009/03/paltridgearkingpook.pdf

The Pierce paper:

http://meteora.ucsd.edu/~pierce/papers/Pierce_et_al_AIRS_vs_models_2006GL027060.pdf

As I understand it, pan evaporation rate has a lot to do with photons, as distinct from temperature. So it has declined because of aerosols. This is a different matter from the capacity of the air to hold moisture once the evaporation has occurred.
Are you going to persist in calling Dessler's statement an egregious error just because he omitted to say "all else being equal"? A bit rough.

Depends what you mean by "what Spencer is saying". If you mean the bit where he says clouds are a forcing not a feedback, I've no idea how that could be correct. The calculus of logic says that if you assume a falsehood you can infer anything, so taking that as correct does not seem fruitful.
He could well be right that clouds are (or will become?) a negative feedback, and/or that overall positive feedback has been overestimated somewhat. But until it is shown with some degree of confidence that positive feedback is so low we really don't need to worry about doubling CO2, I don't see how it should affect policy.

There is evidence that, for a given heat input, evaporation is faster with incoming visible light than IR. The photon energy level appears to be significant in the process. See e.g. http://www.answers.com/topic/global-dimming.

You miss the point Derek; a feedback is a response to something, in AGW parlance, a forcing; AGW recognises 2 forcings, CO2 and Insolation, which is stupid in itself because the primary by-product/forcing from burning fossils is water; but let that pass.

On that definition S&W observe, with reasoned justification, that clouds often exhibit non-feedback behaviour; they are not responding to anything discernible. So, are clouds a forcing or a feedback?

To refresh everyone’s memory and make sure we are talking about the same thing; a forcing is an exogenous factor which has a climatic effect; now CO2 is already in the climate system and humans are natural but we are told that human CO2, ACO2, is exogenous to the [natural] system and therefore a forcing; on that basis cloud seeding would make those clouds exogenous. What about CR caused clouds? If you accept Svensmark, Shaviv, Veizer views on CR, CRs cause clouds to form so the CR is the forcing but the clouds are still feedback. This confusion comes from the IPCC definition of forcing: Christopher Game explains the limitations of IPCC defintion of forcing:

“forcing” can include any amount of internal state variable contribution, as well as external driving function contributions. And according to this IPCC formalism, there is only one dynamically distinct internal state variable, the climate temperature, that functionally determines the apparently distinct but really merely functionally dependent “feedbacks” of their formalism.”

By including internal or endogenous factors as forcings and using only temperature [and therein radiative imbalance] as the measure of those forcings the IPCC ignores the fact that what it desigantes as feedbacks, such as clouds, can be unrelated to temperature or radiative flux; as Spencer and Brasell note:

“Since it is well known that the processes that control cloud formation and dissipation are myriad, complex, and in general not perfectly correlated with surface temperature variations
(e.g., vertical temperature and water vapor profiles, horizontal temperature gradients), the existence of nonfeedback sources of cloud variability should not be unexpected.” From:

http://www.drroyspencer.com/Spencer-and-Braswell-08.pdf

By regarding clouds as a +ve feedback the IPCC modeling artificially inflates climate sensitivity. Even if we ignore Spencer and Braswell’s legitimate concerns about the stochastic, non-feedback nature of clouds and look simply at the radiative effects of clouds and cloud types we see that clouds, en toto, are a NEGATIVE feedback:

http://stm.arm.gov/2008/presentations/0310/7_Dupont.pdf

If I trawl through your acronyms and sentences with all words larger than average you are saying - If human emissions of CO2 result in a cloud covered earth then it will act to provide a negative feedback and cool the earth. But this is not what is happening.

Water vapor is an active energy transfer medium. It moves in and out of Liquid solid and vapor states in the atmosphere. Any imbalance in temperature and humidity results in a processes which act to dissipate energy. The more energy the faster the process and the more extreme weather we get. It also acts to create areas of cloud and no cloud.

CO2 does none of this, it passes more slowly through its "carbon cycle" dissipates relatively evenly and remains in the atmosphere for 100+ years on average. Although it traps and can hold thermal energy it does not move between phase states to does not participate much in the weather itself.

Of all the CO2 dumps in the atmosphere I understand the carbon cycle deals with most of it. The issues is most of it, I understand that only six percent is not taken up. But this is six percent more every year. Compound formulas show you how this can get to double its concentration in a reliability short period.

CO2 can exist above and below clouds yet its main damage occurs when it stands between the earth surface as an infrared emitter and outer space. Clouds can reduce this infrared by reflecting light before it reaches the surface but they need to occur substantially more often to offer the cooling effect to counter the enhanced greenhouse effect.

No, you don't have the forcing/feedback distinction quite right. It is a feedback if there is a circle of causality that involves surface temperature. If it affects surface temperature but is not in turn affected by it by any means then it is a forcing.
But there is a subtlety here - it will depend on the timescale you're looking at. If you're looking for effects in a 24 hour period then a feedback that takes months will look like a forcing. That's why, although increased temperatures do increase CO2 levels over periods of years and decades, for the calculation S&B did clouds are a feedback but CO2 is a forcing.
They are quite right to say that clouds are not pure feedback - there are influences on them which are in themselves forcings, but I'm not sure that anything is pure feedback. It may turn out that we need to discriminate different types of cloud here.

But we're drifting away from Dessler's statement, which was about water vapour, not clouds. Water vapour is clearly a positive feedback directly, as well as encouraging cloud formation. It is possible that via the temperature->water vapour->cloud->shading path that water vapour could act as a negative feedback overall, but highly unlikely. So I say again, calling Dessler's statement an egregious error is downright ridiculous. Until you withdraw that I see no further point in debating you.

Andrew - May I also ask ?

The climate paleoclimate temperature and CO2 basically resembles a sawtooth wave with a fast attack and slow decay. The atmosphere is quicker to warm and slower to cool because the causes of warming are different from the causes of cooling - and these processes have different time frames.

Warming - Increased isolation (Indicated by a very slow onset of warming compared to present day) then amplified by feedback loops such as CO2 and water vapor.

Cooling - Erosion by CO2 (mild acid rain) and capture through geological sequestration and biological processes. Very long decay to reach a glacial period.

Not withstanding the above the current trends are much faster than in prehistory so it may be fair to say all bets are off when it comes to timing if not the effects of increased CO2 ?

I suppose it may be best for Andrew to answer that question. But any greenhouse effect is deeply intertwined with rising temperatures and there are dozens of systems that are primed to release further greenhouse gasses with temperature, even my bush composting toilet does that. To suggest that temperature could rise and greenhouse gasses not increase, from the biological and fossil carbon sinks that cover the earth, would be an extra-ordinary claim (demanding extra ordinary evidence) - I would think it impossible to remove feedback loops and there additive effect, thus tipping points from consideration.

Most of the pants which have lived in the whole of earths history are now dead, many sequestered into fossil fuels and much frozen under ice. If they do not produce greenhouse gasses on combustion they are prone to becoming biologically active if warmed.

Douglas - The time lag you mention is the ratio of CO2 vs temperature in an ice core. Given temperature is a local effect and CO2 is a sample of a global dissipative effect there is a built in delay - 800 years is very small in geological time and the use of proxies for the actual measurement of Temp and CO2 comes with its own complexities. Some discussion suggested that CO2 can permeate into the ice for sometime after it is laid down, further pushing the gap between the two measures. One of the noticeable factors is how, regardless of any delay between CO2 and Temp proxy records how close to lock step they are. One thing we can be sure of is the two are intimately related, and as stated previously the processes that introduce CO2 are different than those that remove CO2. The other clear fact is that this delay does not appear to be present in today's records and most likely this is because our emissions proceed temperature.

It seems that previous climate records would suggest we were now in a period with a slow decline in CO2 and temperature following behind that yet the contrary is measured. This is because the isolation effect from astronomical and continental configurations that kick started warming in the past are not present now to any degree.

You seem an intelligent man (no condescension intended) so why have you been actively trying to dismiss human induced climate change then throw in a possible human induced climate change (atomic testing).

I would love to know, if you suspended your criticism of the the possibility of human induced climate change for a moment - what would it mean to you if it were in fact true ?
Are you concerned about a collapse in the economy ?, are you concerned you will have to grow vegetables in your back yard ? do you have shares in petroleum ?, It would seem that all your arguments point at a dismissal of this particular conclusion rather then establishing the truth of the matter.

I truly, and humbly would like to know what you think. It is not a move of brinkmanship but a real desire to understand.

"Positive feedbacks predominate".

That is wrong. If it were right Earth would have achieved runaway to a snowball or Venus. In fact the temperature range of Earth has been between 10-15C:

http://climateclash.com/files/2010/10/EarthHistory1.jpg

http://img527.imageshack.us/img527/8615/allpaleotemp.png

http://www.scotese.com/images/globaltemp.jpg

This proves that climate sensitivity on Earth is constrained and is best described as being controlled by MODERATING feedbacks.