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."