A nice potted history and many interesting points from a professional meteorologist. There has been alarmism of course - the one absolutely 100% predictable consequence of any scientific claim that man is changing the climate would be the onset of alarmism. Very irritating for a scientist.

But Bill is unconvincing on two central points. First, CO2 levels are rising steadily at 2 ppm per annum, which may be less than in the Villach Statement but still significant, with no sign of slowing down, though elementary physical chemistry tells us that reverse steps like absorption in the ocean will speed up in proportion to the rising concentration. Second, CO2 is certainly a greenhouse gas, so the starting premise ought to be, as it was for Arrhenius in 1896, that its concentration could or even should have an effect on climate. Of course, that expectation does not quantify the effect on climate, which can get mixed up with other separate causes of change.

However, to give the impression in the face of these facts, as Bill does, that there is nothing to worry about is going much too far. Yes, government policies must be prudent because there is a great deal at stake in rejecting fossil fuels as sources of our energy. Finding the right path between alarmism and prudent action is difficult when the politics depends on the electorate's balanced appreciation of the science. I don't think Bill's contribution helps.

Tombee, try to check your facts:
1. CO2 levels are NOT rising steadily at 2 ppm p.a. as you claim, but at 1.45 ppm, so you are out by more than 33%.
2. The % rate of growth of the total atmospheric concentration of CO2 has been only 0.4% p.a. since 1958. That is why Bill K is right it will take until well into the next century before the IPCC’s doubling to 560 ppm is achieved.
3. Arrhenius is constantly being proved wrong – he predicted a rise in temperature of over 3oC for a 50% increase in the atmospheric concentration of CO2, and for the over 40% we have so far managed since 1896 we have yet to reach 1oC.

Actually Tombee, basic arithmetic from the figures you have admitted, shows that the global warmists face a major problem in keeping the alarm going. The 2ppm a year increase which has remained about steady over the past decade adds up to CO2 levels increasing by 50 per cent over the century (2 x 100 is 200, and we're just under 400 now), not doubling. The forecast big temperature increases require a doubling.

Sure the rate of increase could itself increase but it would have to do so a lot faster than anything we're seen in the past few dacades. Then again it could decline. The carbon cycle theory is after all, particularly odd stuff. To get around the problem of C02 emissions being tiny compared to natural flows (about 2 per cent) it requires half of the emissions to be absorbed, they know not how, and the rest to hang around for decades..

Doesn't make a lot of sense to me, but then I'm not a highly trained scientist trying to make facts fit much-loved theories and computer models.

tom .. "3. Arrhenius is constantly being proved wrong – he predicted a rise in temperature of over 3oC for a 50% increase in the atmospheric concentration of CO2, and for the over 40% we have so far managed since 1896 we have yet to reach 1oC."

This seems though to be a central plank to the alarmists arguments .. that this is fundamental physics and is well known.

if it is disproved, why do they still refer to it constantly?

I agree with you .. but wonder, are the alarmists just in denial about this?

Simple fact is that humans are not God. Stewardship of this planet has actually gone backwards since Green religion defying every ounce of logic has been embraced by god deniers. The High Priests and Evangelist of this religion sprout their garbage while raking in the money. So much for the 'science'being settled. Thankfully in Canada one of the parties pushing this rubbish has just been annilated.

I don't normally respond to comments on my comments because all opinions all valuable. But Tom Tiddler accuses me of not checking facts. As it happens, this morning before I penned my little contribution (which was meant to be a caution not to go to the opposite extreme in responding to alarmism) I printed out the last few years of CO2 data from Mauna Loa, got out my ruler and pencil, drew a line of best fit (which I would lay a bet is within a whisker of the Excel fit) and these are the numbers. Intercept on the left axis: 382.5 ppm; intercept on the right axis: 392.5 ppm; time covered: 5.0 years; slope precisely 2 ppm per year.

As for Curmudgeon, I made nothing of the delay in doubling of pre-industrial concentration, so I plead not guilty. Nor did I, or do I, try to make facts fit much-loved theories and computer models; I have none.

All I am saying is that, to a non-alarmist like me, Bill's article, in concentrating on attacking alarmism, goes too far. There is still plenty of room for the prospect of CO2-induced warming and climate change.

Tombee - fair enough.. I wasn't saying you made facts fit theories.. I was referring to climate scientists in general, with honourable exceptions..

The models on which climate change is based are only as good as the assumptions that are made about what will happen to emissions. Problem is that the IPCC has relied on data from the energy industries about how much oil and coal is left - we are already at peak oil and peak coal is predicted to his us some time before 2050 (http://rutledge.caltech.edu/)whilst the focus on reducing CO2 emissions is all well and good there does not seem to be any coherent attempt anywhere to develop an economy that is not dependent on fossil fuels. So regardless of the climate models we will need to make the transition to an economy based on renewable energy. This is particularly important for us here in Australia - we continue to sell off our natural resources and congratulate ourselves but all we are doing is drawing down on our inheritance without ensuring that we have a future.

When reading this article it is important to remember that it expresses an extrememe minority scientific view. It is easy to demonstrate that the vast majority of scientists (97 to 98%) support the theory of AGW and thus would strongly disagree with the key points made by the author (eg: "The future climate directions are not predictable and the evidence for CO2 having a dangerous impact is wanting, especially as rudimentary GCMs are the only acknowledged predictive tool.")

There are numerous reputable national and international scientific bodies supporting AGW and research surveys demonstrating that the vast majority of peer reviewed research papers support AGW. On the other hand we have not one reputable scientific body disagreeing with AGW. We have sites dedicated to scientifically dismantling arguments contrary to the majority scientific view (www.skepticalscience.com) based on peer reviewed papers. And yet another site that comprehensively dismantles the work of such noted sceptics such as Christopher Monckton (let me know if you would like the link).

If you are not prepared to accept the majority scientific view then your rationale is likely to be along the lines of "it is all a big conspiracy". Conspiracy theories seem to be on the rise recently ..... but that doesn't make them any more likely to be valid.

It is not easy to demonstrate that vast majority of scientists support AGW. This 97% figure comes from a study by two academics at the University of Illinois. It refers to 75 out of 77 so called 'climate scientists' who replied to their 2 question survey. The 97% figure was picked up by the media and used to represent the opinions of all scientists rather than of this tiny sample.

If one was interested in putting the cat among the pigeons, one might refer to UAH satellite data which indicates that in fact the whole planet did not warm in the late 20th century. Warming was mostly confined to the northern hemisphere above the 20th parallel. The greatest warming was in the Arctic. Warming in the southern hemisphere was not statistically significant and the Antarctic cooled slightly.

Others have made the same observation, so I can't claim originality, but it remains a curious phenomenon: the Dad's Army of retired meteorologists and geologists who remain so passionately opposed to the theory of human influenced climate change, even though most of them (like Kininmonth) have not published a scientific paper for decades. And - by their associations shall ye know them - one has to be a bit careful of anyone associated with the Lavoisier Group or the IPA, because these are overtly political bodies, with no scientific credibility whatsoever. As for Curmudgeon, taking the lazy option, a shame that a rational journalist so completely misses the point about probability. Most scientists say that the theory (of human influenced climate) is probably true. That means that we should take some account of the theory unless we can categorically refute it. If you can categorically refute it, then do so, in the scientific literature, with sound evidence and rational hypothesis. You will probably win a Nobel Prize, and everyone will be very grateful.

Senior Victorian.

That is not the study I was referencing. A recent study in The Proceedings of the National Academy of Sciences used a data set of 1,372 published climate researchers and their publication and citation history, finding that 97 to 98 per cent of those climate researchers publishing most actively on the topic agreed with the tenets of climate change as identified by the IPCC. They also found the expertise and prominence of the scientists who agreed with the IPCC findings to be substantially higher than that of the scientists who did not. The link is below:
http://www.pnas.org/content/early/2010/06/04/1003187107.full.pdf+html

I note that you did not name a single reputable scientific body (national or international that has been around for a while) that has come out to say they disagree with the AGW theory.

I restate that it is easy to validate the view that the vast majority of scientists support AGW.

As a non scientist I am comfortable to side with the overwhelming majority of scientists especially as it accords with common sense. I find no reason at all to go in the other direction especially when the arguments put forward relate to matters that have been extensively researched and considered by scientists before they reached their conclusions.

I suggest you research www.skepticalscience.com where you are likely to find that the point you raise re satellite data is on their list of over 100 arguments that are routinely raised and that they have addressed and refuted based on peer reviewed science.

Nicco.

Thank you for a very valid and timely commment. It is a curious and unwelcome phenomenon, in part driven by those with a vested interest and money that desire to spread FUD (Fear, Uncertainty and Doubt).

rich, it's the skeptics trying to stop the spread of FUD, that there is no reason for the huge FUD campaign of the climate fear industry .. you seem to be so far up the climate tree, you've lost sight of what's going on I think.

Fear, the world is ending doom if we don't pay a great big tax, and it's URGENT we must do it now, think of the children! (or blow them up, whatever)

Uncertainty, the seas might rise 1 metre or 100 metres by 2XXX, (insert date according to alarm required) the drought will get worse the temperatures will rise to the highest EVA! While we will have record snowfalls and the lowest temperatures EVA!

Doubt, every year we hear that climate change is actually worse than we thought, that temperatures are increasing and falling worse than expected, that ice shelves are melting THREE TIMES FASTER than previously though, that glaciers are melting faster than previously declared .. that every day species are dying out becoas eof climate change .. what else, every time there is a rainstorm, hailstorm, cyclone, earthquake even .. it's climate change .. probably even the deaths of all the unicorns

Skeptics say there is little to worry about, mostly it's natural .. so what part of the skeptical accusation that alarmists are hysterical doom merchants trying to scare everyone and the children, do you equate skeptics to being merchants of FUD?

It's in the interests of all the doom organisations, eco nut climate clubs and all the climate lobby groups and climate scientists seeking yet more grants, to predict doom for the planet, to demand to pay a great big new TAX NOW!, not later, NOW godammit! because it's Code RED, emergency and the earth is in trouble NOW. We can't wait any longer!

If you want FUD, then eco alarmists and AGW believers wrote the book, they are the ones with the vested in interests, particularly all the organizations collecting donations, the scientists getting grants .. what are skeptics getting?.

So what's the FUD that skeptics are spreading?

rpg

Just a reminder that the "AGW believers" are simply accepting of the overwhelming scientific opinion. Skeptics like yourself are taking an extreme minority position on the science presumably because you take offense at what the science says, and take even more offense at the actions that need to be taken to reduce carbon pollution. Unfortunately no amount of ranting and raving changes the basic science.

Alternatively, skeptics are a victim of campaigns funded by individuals and organisations with a vested interest in continuing to make money from oil, coal, gas and mining operations that are threatened by a change to renewable energy. If you think that sounds crazy then read the "Merchants of Doubt" book which explains "how a loose–knit group of high-level scientists, with extensive political connections, ran effective campaigns to mislead the public and deny well-established scientific knowledge over four decades. In seven compelling chapters addressing tobacco, acid rain, the ozone hole, global warming, and DDT, Oreskes and Conway roll back the rug on this dark corner of the American scientific community, showing how the ideology of free market fundamentalism, aided by a too-compliant media, has skewed public understanding of some of the most pressing issues of our era." That should help answer the question you posed of "what are the skeptics getting?".

You may reflect that a previous post pointed out possible connections between the author and organisations with a history of dubious motives and funding sources.

The pro-AGW view of the allegedly-reputable scientific bodies is that concocted and advanced by their politically-motivated governing boards. There is no evidence that it is representative of the views of their members.

"..finding that 97 to 98 per cent of those climate researchers publishing most actively on the topic agreed with the tenets of climate change as identified by the IPCC.."

So in a field where you have to adopt the prevailing orthodoxy to be funded or published, nearly all of the most-published authors adopted the prevailing orthodoxy?

Why am I not impressed?

rich, skepticism is certainly unpopular with believers and the left generally,but is coming out to be more and more acceptable to the general public, who appear to be under a thin veil .. conservative.

You have to accept though that all the articles that are doom laden, hysteric and predicting calamities are from your side .. not mine, our side do not predict doom or end of the world .. emptying of your wallet sure.

I don't get anything material out of skepticism, and I know scientists who get bucketloads .. I think you have a very thin argument there indeed

rpg and others, try and get your information from reputable sources. You say "all the articles ... are doom laden, hysteric and predicting calamities ..." and suggest that this sort of material comes from one side only. In the first place, this is demonstrably not true. But even if it were true, it would suggest that you are getting your ideas from tabloid journalism and dodgy blogs.

If you actually want to learn something, and not just make "doom laden and hysterical" statements about Great Big New Taxes, you should go to the scientific literature. It's (mostly) freely available, online and in your local library. You can if you wish avoid any reference to the IPCC, or the CRU, or even Al Gore, and you will find hundreds of well-referenced research papers dealing with all aspects of climate change, from butterflies to geostatic rebound, from atmospheric gases to oceanic depths. And you will find that most researchers in the various fields of climate science have no doubt about what the evidence is telling them.

JonJ, your observation about having to adopt the prevailing orthodoxy is also demonstrably a nonsense. The scientific literature functions by accepting and examining (and sometimes refuting) heterodox views

I generally agree with the points that the author is making, and I would go on further to argue that what we really need is some kind of Australia-wide system that recognises the likelihood of further droughts, floods and bushfires, and prepares us for them. That's where resilience is to be found, it seems to me.

We have no way of preventing people building houses inside eucalypt forests, and presumably those who do so argue that the likelihood of disaster is small, and it won't happen to them. Presumably those who build houses on flood plains have the same philosophy. Our water utilities have got us to think about water conservation, and that is a great start. Why can't we have an Australian equivalent of New Zealand's GeoNet?

That seems to me the way to go, not down the 'carbon pollution' path. On the evidence currently available, the world has plenty of time to work out the real relationship of carbon dioxide accumulation to global temperature increase. What Australia needs is a serious study of our own climate and the forces which affect it, and us. That would be the right direction for the future expenditure of public money on climate research, which seems mostly to have gone to those who already accept the AGW orthodoxy.

Don Aitken:"What Australia needs is a serious study of our own climate and the forces which affect it, and us. That would be the right direction for the future expenditure of public money on climate research, which seems mostly to have gone to those who already accept the AGW orthodoxy."

The concepts expressed in these two sentences don't appear to be mutually exclusive, Don. Are you trying to say that the climate scientists accepting the AGW 'orthodoxy' are not seriously studying our own climate and the forces which affect it and us?

Doesn't sound right to me.

Don Aitken thinks that we have "plenty of time" to study the relationship of CO2 and climate. This is a familiar ploy by those who want us to do nothing, for whatever reason. It fails for the same reason as Curmudgeon's argument fails: probability. If most scientists think that most climate change is due to the greenhouse effect, it would be simply short-sighted of us not to take account of this. (If you can refute the theory, then please do so!)

And as for having "plenty of time", many quite reasonable researchers are not talking about future climate change, but about the probable effects of climate change which are being seen now, today. Such as: increased bushfire weather, observed plant and animal behaviour pattern changes, glacier and ice-sheet instability, and on and on. This isn't merely theoretical: it's observation and measurement.

And why does Don Aitken think that Australian climate researchers are not studying Australian climate? It is true that much of the work being done is in the northern hemisphere, but Australian research has made very important contributions, notably in the work done on the influence of the Southern Ocean and the Circumpolar Current on global climate patterns; also the international air quality benchmark established at Cape Grim after years of CSIRO research.

nicco "If most scientists think that most climate change is due to the greenhouse effect, it would be simply short-sighted of us not to take account of this. (If you can refute the theory, then please do so!) "

No, you misunderstand .. again, the onus is on you to prove it, not anyone to disprove it..

it's like some idiot claiming the sky is falling, it's up to them to prove it is, not for everyone to run around proving it isn't.

similar to claims of hair spray on rose bushes keeping away elephants .. and other too stupid for words "scientific truths" of the hysteric alarmist community

Amicus, you have been offered scientific material in the past, and you refuse to look at it. This allows you to say: "I have seen no evidence" without actually lying. Your simple-minded idea that the onus is on the scientists to prove their case demonstrates, again, that you have no idea how science operates. To spell it out for you: scientists advance a case, it is reviewed, and published. Other scientists then argue whether or no the case is worth pursuing - not whether it is "proved", or a "scientific fact", but whether it merits further research. This process has been applied to climate science, and specifically the theory of human influenced climate change, for some decades, in the scientific literature. At present, the great majority of climate scientists accept that the theory is 90% probably correct. If you have the means (measurement, observation, even a good hypothesis) to refute the theory, you should submit your research to a reputable journal.

What you call "the hysteric alarmist community" presumably includes the great international scientific institutions, who agree without exception that the theory of human influenced climate change is almost certainly correct, and in many cases (Royal Society, US National Academy of Sciences, Aust. Academy of Science, London Geological Society, American Institute of Physics, and many many more) have issued position statements to that effect. These statements are backed by a wealth of reference to experimental evidence.

for Bugsy and nicco: By 'serious study of our own climate' I meant just that, and not research starting from the view that the primary independent variable is carbon dioxide, and that we need to research globally. Yes, there has been some work on our own climate, especially on ENSO and the comparable Indian Ocean system, and they are powerful influences on our climate that have virtually nothing to do with carbon dioxide accumulations — at least no one has proposed anything sensible to that effect yet. I hope that helps.

Do we have plenty of time? I presently think so. We seem to be entering a longish cool/cold spell, and if I am right that will take the pressure off the 'carbon dioxide is the villain' mantra, and allow climate scientists to look harder at whether or not they can distinguish the signature of human activity within climate's natural variability. So far, no one has been able to do so.

If I am wrong, and warming will resume sooner or later, then there seems nothing much we can do about it except adapt, and that is what I was arguing when I first wrote: we need good systems to deal with climate and natural disasters, however they occur and whatever their cause. Unless China and India come to the party with respect to limiting emissions, it seems pretty pointless for Australia to do so, especially when we are exporting vast quantities of coal to these countries. And the effect of our limiting emissions through a carbon tax will have no discernible effect whatever on the levels of CO2 in the atmosphere for a thousand years, as Dr Flannery has explained.

And a minor peeve: I know that we Aitkins are an illiterate lot, and ought to spell our name with a final 'en' like the much ore numerous Aitkens. But it's not all that hard to see how I spell it. If you want to take issue with me, could you manage to spell my surname my way?

Cheers,

Don

Sorry, Mr Aitken.

Nicco

With respect: many "statements are backed by a wealth of reference to experimental evidence" are not in fact backed by much except a "simulation" of a "projected scenario" that checks a "hypothesis that anthropogenic climate change may effect".

Or words to that effect.

I doubt that the Aitkins are an illiterate lot, and I apologise for mis-spelling Don Aitkin's name. But it does seem that he is wilfully *scientifically* illiterate.

Aitkin has been promulgating his complacent message for some years, and seems to have taken no account of the many and various people who have attempted to point him towards the science. This is so marked, that one must conclude that his motivation, like so many denialists, is not scientific but poltical.

Warming has not ceased, but continues. See: http://www.agu.org/pubs/crossref/2009/2009JD012105.shtml Aitkin (deliberately?) misinterprets Tim Flannery's correct observation about the time lag effect of atmospheric CO2. We are stuck with the consequences of what we have done, for many centuries, but if we persist in adding CO2 to the atmosphere, we will suffer dangerous temperature rises.

As for Aitkin, so for cactus: if you have not seen the scientific evidence, it is not because it doesn't exist, but because you have chosen not to look. (What does cactus think that climate scientist do all day, with their buoys and satellites and balloons and phenological studies?) Personally, I find this a grossly irresponsible attitude. We have only one planet, and if there is even the slightest chance that the world's climatologists are correct, then we should be taking appropriate steps. We insure our lives and houses and belongings on evidence that is flimsy by comparison.

Nicco:

Oh dear no. I have been through WG1 of AR4 on three occasions, and will go through it again before long. I have said several times that the AGW argument is plausible but not compelling, and part of my life for thirty years has been assessing scientists' requests for large amounts of money to enable them to do what they want to do, so I do have some sense of what is involved. My position is neither 'scientific' not 'political': it is simply being unpersuaded that what is said to be the case, is so. Any reasonably educated person can sort AGW out for himself or herself. It's not that hard, though there is a fair amount of reading and thinking to do.

I simply don't agree with what you say. For example, the evidence on sea-level rise and ocean warming is mixed, not all one way. Buoys, balloons and satellites do not show, unequivocally, that human actions are warming the planet, that sea-levels are rising or that whatever warming is occurring is in any way unprecedented. Why do you think they do? What data, and what arguments, are you pointing to? You say that we should act if there is only 'the slightest chance that the world's climatologists are correct'.

I don't agree — and I wonder what you mean by 'the slightest chance' — is that one chance in a thousand, a million, a billion? That just seems rhetoric to me. If it is proposed that we impose a carbon tax which seems unlikely to achieve anything, then I want to know why we are doing this. As someone else has written, extraordinary measures require extraordinary justification.

I don't know where you are coming from, or what drives you. But I'm happy to provide you with some of my own writings in this area if you are interested — and discuss the issues with you when you've read, if you think that would be helpful. (donaitkin@grapevine.com.au)

Writings on the issue of Climate Change - it is obvious that their worth encompasses a great disparity from different quarters, at least on OLO.
At what end of the spectrum, say from 0 to 10, would the various readers place the writings of Don Aitkin (as presented to date on OLO) and those of the Australian Academy of Science (as presented in The Science of Cimate Change, Questions and Answers - dated August 2010 and available on the web). There is little doubt that they would appear at extreme, and opposite, ends of that scale; and the author of this blog’s article would be somewhere in between.

for Colinsett:

You can't have read a lot in this debate if you think I'm at the 'extreme'. I've written quite a bit about the shades of opinion in the AGW debate, and a summary is as follow. There are six obvious positions, and a few religious outriders.

Supporters

1 Strongest. The IPCC has raised the alarm. We must do something now, and that something is to get global agreement to curtail greenhouse gas emissions. The science is clear, and now is the time to act. This is fact the orthodox or IPCC position.

2 Partial Support. There is no doubt that adding more and more carbon dioxide into the atmosphere must increase the world’s temperature. But we don’t know yet how much extra warming there is likely to be.

3 Lukewarm support. Adding more carbon dioxide will very likely increase the temperature, but there are other factors at work too, and the effect may well be pretty small, or even positive for some part of the world. We need to know much more before we do anything.

Dissenters

4 Agnostic dissenters. The orthodox arguments rely heavily on models and conjectures. AGW is plausible and possible, but we need real evidence before we do anything. In particular, we need to be able to distinguish AGW from natural variability. A little warming may be good for humanity, as it seems to have been over the past thirty years.

5 Sceptical dissenters. Many sceptics are well informed about one or other aspect of the central AGW proposition, and can show difficulties with it; they tend to argue that the failure of the orthodox to satisfy them in these domains means that the whole AGW proposition is void.

6 Opponents. AGW theory is just a scam, a sign that the Marxists have taken over the green movement, an attempt by some to construct world government, a conspiracy, a sign of lazy journalists, the effort of bankrupt governments to stay in power, etc. There is nothing to it.

I see myself as an agnostic dissenter.

"real evidence", Mr Atkins?

As opposed to?

for bugsy:

'real evidence' versus 'conjecture'. Real evidence would be observational data showing, for example, that the effect of water vapour and clouds indeed amplified the radiative transfer mechanism through which a doubling of carbon dioxide produced a warming of 3 degrees rather than of one degree. What observational data exist, for the last century, do not support this proposition. The increase of approximately 0.7 peer cent over the last century does not suggest anything like the 3 degree increase conjectured in AR4.

Don and others.

The point is that 1 above represents the mainstream scientific view. This is the view that 97 to 98% of scientists have and every reputable scientific body in the world (if you disagree please list a reputable scientific body that disputes the thrust of the IPCC reports). If you are taking a position based on the science then views 2 to 6 are all extreme positions representing just 2 to 3% of scientific views between them. On this basis Don is at an extreme.

Of course humans base decisions on a whole variety of factors. Things like gut feel, previous experience, their own observations and, probably predominantly in this case, their political preferences. For many people cold, hard blooded science with an unpopular message takes a back seat.

I would say it is extreme to base a decision on something other than science when it comes to climate change, yet it appears to be popular among contributors on the forum. Maybe that is just because common sense is in fact not that common.

Position 1 is based on the hypothetical view of AGW.

The following extracts from physicist Dr John Nicol's paper, "Science without method", Quadrant, April 12, 2011, serve as a timely illustration.

"Conventional thinking on the greenhouse effect is encapsulated in the IPCC’s statement that “We believe that most of the increase in global temperatures during the second half of the twentieth century, were very likely due to the increases in the concentration of atmospheric carbon dioxide”.

Clearly this statement would be better worded were it to have been framed as a hypothesis rather than a belief, and treating the statement that way allows it to be rigorously tested (“beliefs”, which are unable to be tested, fall outside of the spectrum of science). In the real scientific world, for such an hypothesis to survive rigorous scrutiny, and thereby to perhaps grow in strength from a hypothesis to a theory, requires that it be examined and re-examined from every possible angle over periods of decades and longer.

Yet in contemporary research ... and despite enormous expenditure, not one serious attempt has been made to check the veracity of the numerous assumptions involved in greenhouse theory by actual experimentation.

The one modern, definitive experiment, the search for the signature of the green house effect has failed totally. Projected confidently by the models, this “signature” was expected to be represented by an exceptional warming in the upper troposphere above the tropics. The experiments, carried out during twenty years of research supported by The Australian Green House Office as well as by many other well funded Atmospheric Science groups around the world, show that this signature does not exist." (To be cont.)

(Post cont.)
"In addition, the data representing the earth’s effective temperature over the past 150 years, show that a global human contribution to this temperature can not be distinguished or isolated at a measurable level above that induced by clearly observed and understood, natural effects, such as the partially cyclical, redistribution of surface energy in the El Nino. Variations in solar energy, exotic charged particles in the solar wind, cosmic ray fluxes, orbital and rotational characteristics of the planet’s motion together provide a rich combination of electrical and mechanical forces which disturb the atmosphere individually and in combination. ... the “human signal”, the effect of the relatively small additional gas that human activity provides annually to the atmosphere, is completely lost, being far below the level of noise produced by natural climate variation.

So how do our IPCC scientists deal with this? Do they revise the theory to suit the experimental result, for example by reducing the climate sensitivity assumed in their GCMs? Do they carry out different experiments (i.e., collect new and different datasets) which might give more or better information? Do they go back to basics in preparing a new model altogether, or considering statistical models more carefully? Do they look at possible solar influences instead of carbon dioxide? Do they allow the likelihood that papers by persons like Svensmark, Spencer, Lindzen, Soon, Shaviv, Scafetta and McLean (to name just a few of the well-credentialed scientists who are currently searching for alternatives to the moribund IPCC global warming hypothesis) might be providing new insights into the causes of contemporary climate change?

Of course not. That would be silly. For there is a scientific consensus about the matter, and that should be that."

for Rich 2:

Raycom's Nicol quote is sound, but I should answer your point myself.

First, you are raising an argument from authority. I have already said that each of us is allowed to look at the AGW issue and form our own opinion, after reading and thinking. So it doesn't really matter what others think, unless you're not prepared to do that work. In that case you either put the subject out of your mind altogether, and have no opinion, or you follow an authority that appeals to you for some reason. If you do the work, you'll discover that the matter is not nearly so clearcut as it is presented. Then you have to decide where you sit. All those positions I wrote about above have plenty of adherents. The IPCC represents only one of them.

But, second, it simply isn't the case that 97% of scientists agree, or whatever statistic you want to use. No one has ever polled all scientists, or even all climate scientists. The fact that learned academies have expressed opinions doesn't mean that their members all agree with that opinion. In the case of the Royal Society and the American physics body, there have been and are presently disputes within the bodies about ought to be said about AGW.

For my part, I'm not much persuaded that orthodoxy ought always be bowed to, especially after learning that the long and difficult operation I went through to prevent further duodenal haemorrhages was really unnecessary, since my ulcers had been caused by a bacterium, helicobacter pylori. Orthodoxy is usually sound, but it can be wrong from time to time, too. I think it is likely to be shown to have been wrong about AGW, for good reason.

It is worth finding things out for yourself, sometimes.

Raycom,

Dr John Nicol who seems to inspire your comments is chairman of The Australian Climate Science Coalition (ACSC) a climate change skeptics website created by the the Australian Environment Foundation (AEF), a spin-off group created by the the corporate funded think tank, the Institute of Public Affairs. Hardly credible.

You go on to imply that the IPCC is either corrupt or stupid by refusing to consider matters. By implication every other reputable scientific body in the world is equally corrupt or stupid since they all endorse the IPCC view. Much more likely that the scientific view proposed by Dr John Nicol has been considered 100 times and found wanting.

You also imply that the IPCC and others have refused to consider solar influences. That was probably the first thing looked at - you can check out www.skepticalscience.com for an advanced explanation of why solar influences have been discounted.

It is so easy for you to quote one or two so called dissenting views, but you can never point to one reputable scientific body that supports these views and invariably the views you quote tie back to organisations with questionable funding arrangements and political aims. Your comments then normally have a dig at the IPCC and the mainstream scientific community with the suggestion that they are corrupt and deliberately promoting science they know isn't true and suppressing the truth. That means that your conspiracy theory is starting to engulf the entire world community of scientists.

Its hard to know whether you are being deliberately mischievous in your comments or whether you have been unwittingly sucked in by those who fund pseudo science to hoodwink the public and create doubt.

Don

Check out www.skepticalscience.com - think it is number 4 "there is no concensus" for some raw data to address your concerns about the 97% I quoted. I am happy to stick to my comment about the overwhelming majority of scientists agreeing with AGW, and therefore by implication that your view is an extreme one in the scientific community.

I suppose my argument is one from authority but I would note the following:

1. Unless you think the whole scientific community is corrupt there are excellent processes open to those who have a better theory. So far none have emerged. As others have noted be a hero and come up with another theory. There are any number of oil, gas and coal companies and political parties that would love to fund you and promote your findings. If you think the whole scientific community is corrupt then you are in fantasy conspiracy land and I can't help you.

2. While as adults we love to make things complicated anyone can look out the window and "see" the carbon dioxide we are busy pumping into the air - 30 billion tonnes a year I think. Shouldn't be a surprise that CO2 concentrations are going up, and with it temperatures. The basic theory is very straightforward, its not like we are dealing with some arcane branch of science beyond the comprehension of normal people.

3. While orthodoxy can sometimes be wrong the odds here are running at 97:3 in favour of the orthodoxy being right. If you want to bet the planet on a 3% chance that a miracle happens then you are rightly called extreme....

Dr Nicol clearly points out that the IPCC failed to apply scientific method. This is not surprising, as the IPCC approach was based on belief, assertion and output from unvalidated climate models that produced alarmist outcomes -- hardly a scientific, professional, ethical approach.

Nor did socalled scientific bodies apply scientific method, choosing instead to align themselves with the IPCC for political reasons, as they were influenced by environmental activists and politically-motivated governing boards.

Until such time that warmists stop their arrogant denigration, pull their heads out of the sand, and start to consider opposing views carefully, they are the ones who are being deliberately mischievious.

Raycom,

So your arguments boil down as usual to "its all a big conspiracy" by IPCC, every reputable scientific body and those environmentalists. You would rather ignore all that carefully considered and peer reviewed scientific opinion, and common sense based on observations and simple science and throw your lot in with pseudo science sponsored on the quiet by vested interests that cannot pass the simplest scrutiny from professional scientists.

This sentence caught my eye when the latest conspiracies surfaced around Obama's place of birth. He produced his long form birth certificate but that wasn't enough for some "Conspiracy theories have the self-sustaining gift of ramification: they sprout new tendrils, like a mad vine that has invaded from another continent. For the committed conspiracy theorist, there is always another angle to explore, another anomaly to scrutinise."

I hope you enjoy your endless and pointless exploring and scrutiny - however sooner or later the majority public view will recognise reality just as they did with the link between tobacco smoking and cancer. Unfortunately it just takes a while ....

Rich 2:

Head-counts don't prove anything, as Einstein once said. I don't take any notice of them, even of the Oregon list of 31,000 scientists, including 9000 PhDs, who don't agree with AGW.

And as for Skepticalscience, which I have gone to, it is simply a pro-AGW site that tries to find an answer for every objection that sceptics have made. It is not in any way balanced, and some of the reasoning in its entries is awful. Lubos Motl has done a nice piece of surgery on it, which you can read at http://motls.blogspot.com/2010/03/john-cook-skeptical-science.html.

And I think you miss the point about debate. I don't have to have a better 'theory' in order to show that AGW is unpersuasive. The null hypothesis is that the Earth's climate system is subject to a number of forces that cause change, and we do not yet wholly understand those forces and how they interact. I'll call that 'natural variability'. Those arguing that AGW is the primary driver of change need to show that this is indeed the case, and what I do is to point out what I see as errors in their argument and evidence. They may still be right, but so far they have not been able to make their case at all well, and that is after a very large amount of money spent on research. If you like, my theory is that we still do not know enough to start acting as though we do.

"I don't believe in the conclusion, therefore I don't have to consider the science." This Aitkinian/Curmudgeonish approach is both lazy and insidious. All the science is wrong because the conclusion is wrong. How do I know the conclusion is wrong? Because I say so. Easy.

Aitkin's dismissal of the Skeptical Science website is characteristically shallow. Perhaps he should have another look. He will find that Skeptical Science, while having an opinion (that the science, while incomplete, is generally valid) is careful to quote contrary opinion, and to great lengths in examining contrary opinion, and to very great lengths in providing references to research papers from the scientific literature. If this is advocacy, let's have more of, rather than the un-referenced smears of the denialists.

Raycom links to Quadrant and follows with this gem:

>> Nor did socalled scientific bodies apply scientific method, choosing instead to align themselves with the IPCC for political reasons, as they were influenced by environmental activists and politically-motivated governing boards.

Until such time that warmists stop their arrogant denigration, pull their heads out of the sand, and start to consider opposing views carefully, they are the ones who are being deliberately mischievious. <<

ROFL ... should have taken out insurance on coffee damaged keyboards :(

Don Aitkin, The Australian Academy of Science, as in its “The Science of Climate Change Questions and Answers”, sits squarely in the middle of the road of true scientific agnosticism while doing the rounds of available evidence.
Pulling on your Agnostic colours and taking to the field in this debate, you have played at the opposite end of the field from the Academy. From time to time, some of us punters on the sidelines have observed you kicking an own-goal or two.
One of these was your statement “Carbon dioxide is a fertiliser, the more of it the better”. It is an odd statement, especially for anyone who has heard of Paracelsus, who 500 years ago noted that a remedy becoming a poison depended on the dose rate; or of the farmer who has watched his crop expire from an excessive application of nitrogen fertiliser or of a trace element such as molybdenum.
Neither does it sit well with Arhenius’ establishment, a century ago, of carbon dioxide as the fundamental regulator of the planet’s temperature. Barrie Pittock noted, in his book Climate Change, that during some of previous geological eras atmospheric carbon dioxide concentrations had been much higher, and “life thrived”. That was, it bounced back after mass extinctions of species which were adapted to lower levels. Ian Plimer used the same quote as Barrie, but applied it, in an act of dissimulation, to Homo sapiens in the present era.
I, as one of the those inexpert observers as this “agnostic” match is played out, sometimes wonder if you realize which set of goal posts you are heading for. In regard to the author of this article we are commenting upon - maybe he is wandering around the touchline shifting the goalposts

Thing is, science can pretty well measure (with a high degree of accuracy) the energy coming in, and going out of, the Earth System - the terrestial biosphere, oceans, troposphere/stratosphere.

The Earth System is reacting to this increased energy by trying to maintain equilibrium. The manifestation of this process is seen in changing weather patterns.

Despite assertions and protestations to the contrary, natural variability alone cannot explain this change in energy/heat flux that the Earth System has been experiencing. Not the Sun, cosmic rays, magnetics, volcanoes, tectonics, Milankovitch cycles, nothing nada yada yada.

Conservative 'naysayers' want to curtail spending on research (e.g. satellite monitoring) that would provide definitive results on climate change. If not to remove the goal posts, then why?

It seems to me that so called sceptics (agnostics even) are relying on unknown 'unknowns' to explain the global warming that the planet has been experiencing. While some real scientists/sceptics are trying to seal this envelope (Spencer comes to mind) they have not been able to satisfy some basic physical or chemical principles. If they do they will overturn science as we know it, make squillions in the process, and no doubt add a Nobel to their mantle piece.

Don

You really are scraping the bottom of the barrel in referencing Lubos Motl. Do you actually check out any of the people you seem to admire or follow? A cursory google of Lubos Motl will tell you that he was either forced to resign or was fired from Harvard and that he appeared to be "unstable". Enough said.

Yet when it comes to www.skepticalscience.com your standards have ratcheted up from "anyone will do" to "super human". The site has multiple levels of explanation for 158 standard arguments all tied back to peer reviewed science. And by the way it quotes your 31,000 scientists argument and provides a 10 minute video to debunk that. Apparently only 0.1% (about 30) of the survey respondents even claim to be climatologists.

Don, I suggest if you are going to provide links to people you check them out first otherwise you are just left looking silly if your premise that nobody will bother checking them out doesn't hold true.

Rich 2

I think I have trespassed on this thread long enough. As it happens, I don't check out whether people are said to be unstable or whether they have been forced to resign from Harvard. Life is too short. I read what they say, and try to asses their arguments. If they present evidence, I try to assess it against all the other evidence that is said to be relevant. Yes, it's quite a lot of work. But my joint reading of skepticalscience and of Lubos Motl suggests to me that the latter is more often hitting the bulls eye. Part of the reason is that SS is arguing a case, and trying to make every post a winner, whereas Motl has the easier task of pointing out logical inconsistencies, poor argument, and a reluctance on the part of SS to consider inconvenient data. There's quite a lot of that.

I do think you go on missing the point, but I guess that is part of the problem (and of the fascination) of this issue. Because I don't like arguments from authority, and never have, and warned my students against them, I try to find out for myself where i think the matter is important. I've said, often, that the AGW case is plausible, but at every turn it is based on poor data and conjecture, rather than on good data and and a solid base in science. The most solid science is that of radiative transfer, but you can't build the whole AGW structure on that!

I assume that in time we will learn more, and we will then have a better grasp on what to do. I don't think I'm being either bland or complacent. That's just how it appears to me at this moment. You feel differently — well, you are entitled to your view. I neither agree with you nor think your position is sound. And ad hominem attacks on third parties don't, in my view, improve your case.

Rich 2, Bonmot, Nicco et al persist with defending the existence of AGW, when its actual status is that of an unproved hypothesis. Despite billions of dollars of research, no one has yet succeeded in proving it.

The best that AGW proponents can do is assert, for example:

. the IPCC: “We believe that most of the increase in global temperatures during the second half of the twentieth century, were very likely due to the increases in the concentration of atmospheric carbon dioxide”;
. the government’s Multi-party Climate Change Committee's sole scientist member, ANU’s Professor Will Steffen: " there is 100% certainty that the earth is warming, and that there is a very high level of certainty it will continue to warm unless efforts are made to reduce the levels of carbon pollution being sent into the atmosphere."

neither statement qualifying as scientific evidence of the linkage between anthropogenic CO2 emissions and dangerous global warming.

The compelling scientific evidence that is required to prove the AGW hypothesis has not been produced. In fact, the following statement of Dr Nicol says it all: " the data representing the earth’s effective temperature over the past 150 years, show that a global human contribution to this temperature cannot be distinguished or isolated at a measurable level above that induced by clearly observed and understood, natural effects, such as the partially cyclical, redistribution of surface energy in the El Nino. "

Don and Raycom.

I have already pointed out to you gently that Dr Nicol and Lubas Motl have unimpressive scientific pedigree but I see you both continue to reference them. You are using them both as "expert witnesses" and as in a court it is entirely appropriate to test them to see if they are the "experts" you claim. They are clearly not and I don't see that testing as an ad hominem attack merely common sense.

Don - as an example #13 on the link you supplied has Lubas Motl claiming "Even 5 °C of warming would be a net positive." Is that a statement you feel comfortable with?

Raycom - you talk a lot about the need to have AGW proved. Check out this link to a 10 minute video http://scienceblogs.com/insolence/2011/05/the_best_ten_minute_summing_up_of_a_scie.php
The video sums up "multiple lines of evidence supporting AGW. The same sort of reasoning applies to every major scientific consensus, be it evolution, the germ theory of disease, the scientific consensus that vaccines do not cause autism, or whatever. There is no single study that "proves" a scientific consensus. Nearly always, there are many lines of mutually supporting evidence that converge on the same conclusion or set of conclusions. That's the one thing advocates of pseudoscience just don't get. They have a tendency to think that there's a "magic bullet," one study that "proves" the consensus, hence their demand for "just one study" that "proves" a consensus, a demand I've seen from creationists, anti-vaccine activists, and supporters of various forms of quackery. In most cases, there ain't no such beast. That isn't how science works."

Rich 2, you obviously do not like to acknowledge the fact that there is no scientific evidence of the linkage between anthropogenic CO2 emissions and dangerous global warming.

Instead of denigrating Dr Nicol and rambling on about your AGW beliefs, can you simply address and be specific about the problems you have with his statement: " the data representing the earth’s effective temperature over the past 150 years, show that a global human contribution to this temperature cannot be distinguished or isolated at a measurable level above that induced by clearly observed and understood, natural effects, such as the partially cyclical, redistribution of surface energy in the El Nino

Rich 2

I join with Raycom. It's no good just repeating what you said before. If that were any kind of argument, it would be called 'argument by repetition'.

Read what I said again. I didn't say that Motl was always right. I said that he had an easier task, since he only had to show errors in data and evidence, while SS had to plead a case. In my opinion, as I said above, Motl is more often correct. I don't have to agree with everything he says. I try to get close to the reality by assessing data and comparing arguments. It is time-consuming, and I said it was.

And as for your quote, I don't think that there are multiple lines of evidence supporting AGW, though that's such a vague statement it might mean anything. There is, as yet, no clear AGW signal that can be detected from within the noise of natural variability.If you think that there is, for heaven's sake tell us of a few papers that convincingly show that, and not just quote somebody else' assertion.

Raycom,

There are three key problems with the statement from Dr. Nicol to the effect that natural cycles explain the earth's effective temperature over the past 150 years:

1) A natural cycle requires a forcing, and no known forcing exists that fits the fingerprints of observed warming - except anthropogenic greenhouse gases. For the full story http://www.skepticalscience.com/global-warming-natural-cycle.htm

2) Dr. John Nicol and The Australian Climate Science Coalition (ACSC)do not qualify as a reputable source of scientific knowledge. Their views are driven by the political interests they represent not by a desire to find the scientific "truth".
The ACSC has links which go back to The Institute of Public Affairs (IPA). IPA is a right-wing corporate funded think tank based in Melbourne. A key policy is to refute the science involved with environmental issues such as climate change. It relies heavily on funding from a small number of conservative corportions such as BHP Billiton, Shell, Mobil and Woodside Petroleum.
In 2005 the IPA set up the Australian Environment Foundation which, in turn, set up the ACSC. Dr. John Nicol is Chairman of the ACSC. It has as a "core principle" that "Global climate is always changing in accordance with natural causes and recent changes are not unusual". It says its mission is to "promote open scientific debate on the causes of climate change" .............. yet it starts of with a view of what the science says?!
That doesn't seem right to me - does it seem right to you Raycom?

3) In the field of climate science, the consensus is unequivocal: human activities are causing climate change. There are no national or major scientific institutions anywhere in the world that dispute the theory of anthropogenic climate change. Not one. If the natural cycles theory has any merit at all there should be but there isn't.

Don and Raycom - Did you watch the video I provided the link for? Did you find it useful? Has it caused even a shadow of doubt in your mind?
Your calls for "where is the evidence?" I addressed in my previous post.

Rich 2:

We're not going to get anywhere. You are stuck on the view that consensus is really really important, that 'the science' has multiple lines of evidence, that learned academies are disinterested and always right, and that people's arguments and evidence can be dismissed if they seem to be associated with groups of whom you disapprove. So you keep on repeating the same stuff.

You say that a natural cycle requires a 'forcing', as though this was clear and self-evident. It's neither, and it presupposes that there is somehow an equilibrium in climate which carbon dioxide is disturbing. What is that equilibrium, and when have we experienced it?

I watched the video for a couple of minutes, and I can see why you like it, because it starts from the same premises as you do. But when I saw the cigarette I knew what was to come, and switched off. I've seen it before — that's old stuff, and it doesn't help, because lung cancer and global warming are two quite different issues.

I leave you to your consensus.

It seems that Aitkin is stuck on the view that a scientific consensus based on the preponderance of evidence can be simply dismissed because it doen't suit his unsubstantiated opinion; that Aitkin is stuck on the view that the virtually unanimous and stated view of the world's scientific institutions can be dismissed for the same rerason; that a "natural cycle" happens without any causative agent; that the holocene era has not been an era of relative equilibrium; that the basic physics of atmospheric carbon dioxide has not been demonstrated; that there is no association between the tobacco denialists and the climate denialists ... you have to wonder. And why, if everything is for the best in Aitkin's world, does he even bother to enter the argument? He certainly isn't attempting to refute the science.

Nicco:

In order,

(i) I have looked into the 'consensus' and it is wanting; in any case, one is entitled to ask questions and consider the answers, whatever experts say.
(ii) How many times does one have to point out that the 'view' of the Royal Society is that of its executive, and that the RS has already had to climb down from its former extraordinary position because of the objections of Fellows not on the executive.
(iii) You seem to assume that we know everything that is to be known about natural variability, and that is both wrong and arrogant on the part of anyone who asserts it.
(iv) The apparent increase in warming in the last century is well within the variation that has already occurred with the Holocene.
(v) I have already said that I can accept the black body argument for radiative transfer through which a doubling of carbon dioxide will lead to a one degree increase in temperature, all things being equal. The rest is conjectural.
(vi) As a former smoker who is opposed to smoking I do not deny the probability that a smoker decreases both his/her life expectancy and quality of life. The rest of your point is an empty smear.
(vi) Why do I enter the argument? In the hope, pretty well exhausted on this thread, that I could persuade someone to go and do some reading and thinking, ask a few questions, and come to his/her own view about AGW, rather than parroting what others say and think.

You never know. There may be someone out there who is reading but not commenting...

Don Atkins:"(iii) You seem to assume that we know everything that is to be known about natural variability, and that is both wrong and arrogant on the part of anyone who asserts it.
(iv) The apparent increase in warming in the last century is well within the variation that has already occurred with the Holocene."

Well, yes to both of these points, but you left out some crucial detail.
You, and many others, appear to pinning their hopes of explanation of what is causing the warming on something that has hitherto been unmeasured or is currently 'unknown', when a quite plausible explanation has been tested through multiple lines of evidence and the signals from known natural variability have been controlled for in the analyses.

As to the natural variability of the Holocene, there are many sources of variability, that have occurred in the past. But where are they now? Why do they not show up as being causative of warming?

Where is the 'natural' explanation for the current warming? I haven't been able to find one, have you? Why reject the plausible (and testable) explanation in favour of a big 'unknown'.

What I have found is that there does appear to be an anthropogenic signal in the data:

Air Temperature and Anthropogenic Forcing: Insights from the Solid Earth
Dickey, JO Marcus, SL, de Viron, O
JOURNAL OF CLIMATE Volume: 24 Issue: 2 Pages: 569-574 Published: JAN 15 2011

Statistical assessments of anthropogenic and natural global climate forcing. An update
Schonwiese, CD, Walter, A , Brinckmann, S
METEOROLOGISCHE ZEITSCHRIFT Volume: 19 Issue: 1 Pages: 3-10 Published: FEB 2010

Bugsy:

I said that AGW was plausible! But it's not compelling, at least for me. And you use the phrase 'multiple lines of evidence', as do so many, without ever mentioning any of of them. And again, 'climate science' as we know it today is based on large computer models and is only twenty years old. We'll know a great deal more about all of this, I should think, in another twenty years. Models are not evidence of anything — they offer possibilities, clues perhaps, that have to be tested against observations.

Real observations have shown that the proposed hot spot in the troposphere cannot be found, and at least to that extent, the AGW signature does not yet exist.

Now I've done as much work on your two articles as I can. The second is in German, and mine is too rusty to help. But both abstracts show that these are model exercises. The one in German seems to start with the assumption that AGW exists, so that's not a great help, and moves quickly into how to mitigate its effects.

The Dickey article is simply a piece of modelling that produces three variables that seem to correlate, but even the authors don't know why. And the assumption, at the end, that all this bodes woe for the 21st century suggests to me, again, that the authors start with the assumption that AGW exists.

Do you see the problem? If you put AGW into your model you will show that it exists! What I need is a proposition that can be tested in the real world, like the tropospheric hot-spot. If that can be found, we can then at least distinguish AGW from natural variability, and see how big it is, and then assess its likely effects.

The natural explanation (null hypothesis) for current warming is a rebound after the Little Ice Age. We don't really know why the LIA occurred, any more than we know why the Mediaeval Warm Period occurred, or the Roman one. There are conjectures, but that is all.

Scientific 'models' are built upon real observations, Mr Atkins.

But I do see a problem, you are an abstract extractor, not a paper reader. Otherwise you would know that the second reference is in English, not German.

Again, we don't know but we have some ideas about the Medieval 'warm period' (there conflicting data about this one) and the LIA, including solar activity. Solar activity strongly correlates with climate and temperature observations, well up to about the mid to late of the 20th century anyway. However, when we look at all these possible influences we don't see any change in their effects, i.e. they cannot explain the current trends.

I will repeat, scientific models are built on data and validated with observation. That you keep repeating that this approach is worthless leads me to suspect that you are probably more familiar with the 'economic' approach to modelling. In that I would agree.

You agree that the AGW approach is plausible, well I would certainly contend that after looking for alternative 'natural' explanations and not finding them, it is the MOST plausible. It is the crowd that say that there are 'natural' explanations without identifying them are in the faith-based camp.

How often will Aitkin go on repeating the furphy that the Royal Society retracted its considered views on climate change? Its most recent statement (September 2010) was prepared by a highly qualified working group and is extensivley referenced, (perhaps stimulated by a small rump of RS members, led by denialist Nigel Lawson) and it concludes (par.57): "There is strong evidence that changes in greenhouse gas concentrations due to human activity are the dominant cause of the global warming that has taken place over the last half century. This warming trend is expected to continue as are changes in precipitation over the long term in many regions. Further and more rapid increases in sea level are likely which will have profound implications for coastal communities and ecosystems."

This statement is in general agreement with statements made by many of the world's leading scientific institutions. These statements are well-referenced and are based on scientific measurement and observation. (This is easily checked.)

Aitkin's complacent view that only he is capable of reading and thinking about the issue, rather than "parroting" the opinions of others, is arrogantly wrong. A number of contributors to this forum have shown that they have read widely and given serious thought to what is a real problem. It suggests, rather, that Aitkin is so certain of his ground that he needs neither evidence nor expertise. This in turn suggests that his motivation has little to do with scientific investigation, but much to do with preserving the status quo.

Bugsy,

I can't get past a pay-wall for the Dickey one, and I couldn't find an English-language version of the German paper. If you have one, could you send me the URL? I read papers where they are accessible, and abstracts when they're not.

Of course, models are built on observations where they exist. But so far the GCMs don't, for example, deal well with clouds, water vapour, the oceans and other factors. These are estimated ('parameterised'). I haven't said that GCMs are worthless, but that they don't provide evidence — separate point.

We seem close to agreement about the past, though since science doesn't yet have a thorough-going explanation for past 'extremes' we cannot rule out that whatever that is could explain some or all of the variability of the last fifty years.

Nicco:

The Royal had on its website until last year what I regarded as a most patronising 'rebuttal' of criticisms offered of the orthodox view of AGW. After protests from with the Fellowship this was deleted, and replaced with a new statement. I would agree that it is still pro-AGW, but at last, and at least, there is some concessions that much is uncertain — which was not the case prior to September last year.

You say that the Royal's statement is consistent with statements made by other bodies and that they are (all) 'based on scientific measurement and observation'. To the extent that measurement and observation are involved, this is true. But much of 'the science' is conjectural, and based on models, which do not provide evidence or observation. And much of the data is very rubbery: look closely at how the global temperature anomaly is calculated, and you might begin to wonder how on earth it can be expressed to three decimal places.

I won't comment on your ad hominem remarks.

Bugsy,

I've now found the Dickey paper, and there's not much more I can say. Its figure uses the familiar temperature curve for the 20th century, which is then 'corrected for anthropogenic effect according to GISS ModelE (red; Hansen et al 2007)'. Now that puts in AGW. Then they argue for this procedure as follows: 'Because anthropogenic effects have significantly altered Earth's climate since the start of the industrial revolution ...' they correct for these effects. How do we know there are such effects? Well they quote Susan Solomon's 2007 paper. But that doesn't show them, but argues that they exist.

And so on. Do you see the circularity there? Where is the independent evidence of the effects? It may be true that the Earth has been warming, though by how much depends on the data, and they are really rubbery. But it is not surprising that the authors find that there is an anthropogenic effect, because they started with it.

Bugsy,

I ought to have added that the Susan Solomon reference is simply WG1 of AR4, and is not quite a thousand pages long. Nowhere in it do the authors say what Dickey et al state. WG1 does not anywhere show conclusively that the AGW signature can be detected within natural variability. It argues for it, yes. Nor does it state that human activity has affected the Earth's climate since the industrial revolution. Actually, the more common argument is that there has only been natural variability until 1950 or thereabouts.

Rich2
Your "three key problems with the statement from Dr. Nicol" are based on assertion.

(1) Your 'skepticalscience' reference consists of a series of assertive statements, including:
"Scientists keep track of natural forcings, but the observed warming of the planet over the second half of the 20th century can only be explained by adding in anthropogenic radiative forcings, namely increases in greenhouse gases such as carbon dioxide."

The reference is devoid of any scientific evidence supportive of the claim that " the observed warming of the planet over the second half of the 20th century can only be explained by ... increases in greenhouse gases such as carbon dioxide." This simplistic assertion derives from IPCC reports broadly arguing that the authors cannot think of any reasonable source of global warming other than the increasing level of some greenhouse gases, so that must be the cause.

(2) Your claim that " Dr. John Nicol and The Australian Climate Science Coalition do not qualify as a reputable source of scientific knowledge. Their views are driven by the political interests they represent not by a desire to find the scientific "truth" ", is unfounded.

The ACSC members have a wealth of scientific knowledge and experience; are honest, dedicated and responsible; they employ scientific method to seek out the scientific truth about climate change; they are genuinely mindful of the national (and international) interest; and they do not have any political axe to grind.

They have not "been bought" as some scientific institutions and scientists have been (see separate post).

Presumably, the IPA seeks their views because they know what they are talking about and are always willing to assist.

3) "In the field of climate science, the consensus is unequivocal: human activities are causing climate change."

The consensus is political, not based on scientific evidence of linkage between human activities and dangerous global warming.

As already argued, scientific institutions are in political consensus with the IPCC. Their political objective is to promote the 'certainty' of AGW.

With regard to the video link, Don Aitkin's comment spared me the time of a look.

The following extracts from the Garth Paltridge article, " A Less-Than-Noble Consensus", published in the AFR 3 May 2011, show how scientific institutions and climate researchers have " been bought".

"We hear that Julia Gillard is happy to have the CSIRO, the Bureau of Meteorology and the Australian Academy of Science on her side while making her arguments for a carbon tax. Well of course she is. She and her predecessors bought them. And bought them good. Over the last couple of years her Department of Climate Change (the DCC) gave them 27 million dollars in the form of research grants. That pays a fair swag of the salaries of the CSIRO and Bureau climate scientists who make up the majority of all employed climate scientists in Australia.

University climate researchers, while relatively few in number, are vocal enough to be heard in many public forums. Julia has bought them too with another 5.5 million dollars from the same source.

... virtually all climate research in Australia is funded from one source – namely, the government department which has the specific task of selling to the public the idea that something drastic and expensive has to be done to the structure of society in the name of mitigating climate change. And if you think that government agencies shouldn’t be in the game of social engineering, then you are way behind the times. Over the last two years more than 100 million dollars was distributed by the DCC for exactly that purpose.

So there can be no doubt that climate-research grant recipients know perfectly well that scepticism concerning the climate-change story does very little for their careers. One therefore wonders a bit about the much-vaunted consensus of the global warming establishment regarding climatic doom."
(to be cont.)

Extracts from Garth Paltridge article cont.

"Surely there is no way a whole scientific discipline can be subverted, either consciously or subconsciously, by crass materialism? Well, maybe not in the long term. But if past experience is any guide, the sorting out of a problem of vested scientific interest can take many decades.

The average climate scientist is extremely reluctant to go against the tide of official opinion set by the research activists of his field, whatever might be his private thoughts on the matter. Loyalty to colleagues gets in the way, and perhaps also the seductive attraction of a ‘noble cause’. With those sorts of justification, it is much easier for an idealistic scientist to be mindful of the fact that, when Julia buys people, they have to stay bought if they want to continue in the game.

Surely there are independent scientific establishments whose advice can be trusted by both government and public? Well yes there are – most of the time. The Australian Academy of Science is a prime example. But one has to mumble a bit when talking about the independence of such bodies in the context of climate change. They generally don’t have much in-house expertise on the subject, and when asked for advice, are obliged to put together committees of advisors from the relevant research establishments. It is not too difficult to imagine where the advisors come from. Moreover, it costs money to service a committee. Guess where that comes from."

Raycom

I had posed you the challenge of finding just one reputable scientific body that supported your views, but congratulations on at least posting quotes from a scientist. According to Wikipedia Garth Paltridge is one of a grand total of 4 scientists (they have their criteria listed) whose position is that the accuracy of IPCC climate projections is questionable.

As per Paltridge "There are good and straightforward scientific reasons to believe that the burning of fossil fuel and consequent increase in atmospheric carbon dioxide will lead to an increase in the average temperature of the world above that which would otherwise be the case. Whether the increase will be large enough to be noticeable is still an unanswered question."

So he is a long way from being an outright denier which is encouraging. Less encouraging is that the foreword to his book is written by Monckton whose talk slides have been comprehensively demonstrated to be misleading by the simple expedient in many cases of contacting the researchers whose work he quotes and agreeing with them that Monckton had misinterpreted it.

I think you have lost touch with reality if you believe the conspiracy theory. Even if you could explain the situation in Australia (which you can't) then what about the rest of the world? No matter what political power is involved, and therefore the source of some funding, the scientific answer is always the same, and has been over many years and many governments. The premise that governments of all persuasions are pro climate change science is just nonsense. The reality around the world is that governments have done their level best to ignore the science and just hope the problem goes away. The last thing governments want to do is take on powerful vested interests that have a lot of money to spend on lobbyists, advertising and pseudo scientific organisations.

I see you are proud that you didn't look at the video link I provided. You are not going to learn much that way.

Raycom says:
"The ACSC members have a wealth of scientific knowledge and experience; are honest, dedicated and responsible; they employ scientific method to seek out the scientific truth about climate change; they are genuinely mindful of the national (and international) interest; and they do not have any political axe to grind."
Well, if you can believe that you can believe anything. So far as I know, no currently active climate scientist is associated with the ACSC. ACSC "scientists" are the familiar denialist group: Plimer, Carter, Evans, McClean, et al, with no climate credibility. The political axe that they have to grind is huge and obvious. The ACSC was established by the Australian Environment Association, itself a front for the far-right IPA, and involving such right-wing activists as Hugh Morgan, Tom Quirk, and Ray Evans, all associated with the mining industry. The "national and international interest" which they are genuinely mindful of, is the interest of the extractive idustries. This of course doesn't make them wrong, or right, but it makes a nonsense of Raycom's one-eyed claim.