Geoff: I look at it this way (I’m sure you understand) – the ‘Leos’ of this world are stuck between a rock and a hard place – business-as-usual the former, their understanding of ‘climate science’ the latter. They parade their ignorance (innocent though it may be) as a badge of honour, unwittingly digging their holes evermore deeper. Carter tagged himself (and dug his own hole) to the paper of McLean (OLO’s ‘snowman’) and de Freitas ostensibly to counter the fact that he had not written or even contributed to any scientific paper on ‘climate science’, at all.

Carter may be a doyen in geology, but his climatology credentials are sparse, if not lacking altogether. Nevertheless, he seems more intent on doing the rounds of the public speaking circuit these days – his next big event with the Heartland Institute’s annual gabfest in New York (I surmise) with the likes of the inimitable Anthony Watts. Further, it is well known that Carter and McLean (and Plimer for that matter) are stalwarts of the Lavoisier Group – that mendacious Australian right-wing think-tank with direct links to the mining lobby and the ‘Greenhouse mafia’. Of course, this group (like Heartland, CATO, Marshall, etc) spread their tentacles far and wide – the Institute of Public Affairs (IPA) and other nefarious groups like the Climate Change Coalition also come to mind – the latter of which is a favourite haunt of de Freitas (and Vincent Grey) in New Zealand.

As far as Don goes, silence maybe golden. However, I like reading his opinions, particularly on the political science of the so called ‘climate debate’. I would have liked he comment on http://forum.onlineopinion.com.au/thread.asp?article=10186#165173 but then, he may not have even heard of Waleed Aly, watched Q&A, or had the opportunity to read his ‘On the Future of Conservatism: Where the Right Went Wrong’. Nevertheless, I think it worth restating: The “debate” is not about the science ... it is a bun-fight about political ideology - demonstrated at Copenhagen and being witnessed here between Tony Abbott's 'old school', Rudd's centrists, the Green hardliners, and Senator Fielding's faith.

odo, I stand corrected. You didn't mention Bob Carter. You only sprayed colourful epithets.

qanda, I agree the debate seems to be mostly about ideology. It certainly isn't about science. My puzzle has been what people find emotionally threatening in the prospect of changing our lives a bit so as to be kinder to the planet, and ourselves. It sounds like good news to me, but not to many people. Nor is it just about change, because we have had lots of change in the past thirty years, including the deliberate destruction or debilitation of many industries. It's OK to dump textiles, footwear, sugar, many primary products, family farms, etc. etc., but not coal. Ideology is the common thread. Free market, libertarian (big money) world view. Cooperate? Communist! It would be interesting to know how many "sceptics" have right wing political views. I'll have a look at Aly.

I wouldn't characterise Greens as 'hardliners' though. That just invites people to do less than is necessary, and to continue to treat the problem as political. Our petty little political fashions don't dictate reality, the Earth does.

You mention an Anthony Watts. Got a link? I used to know one in my line of business and I'd be reassured to know it's not him.

It is pleasant to be asked to keep the thread going! I simply have other things to do much of the time, so my return is sporadic. I'll get to Geoff Davies in a moment. I am also trying to finish the QE by Waleed Aly, who writes beautifully. I can see that he is going to launch into climate change soon, and I'll comment on that (if I do at all) in QE itself.

Qanda: Who do you think does have 'climatology credentials'?. If there is an undergraduate major in 'climate science' anywhere in Australia, it is very new. There are new centres in the field, and no doubt postgraduate degrees, but on what body of the natural sciences are they based? As I have written before, all those whose work I have read have come to climate from a basic scientific discipline: geology, biology, chemistry, mathematics, physics, statistics. One reason that the science is not (and can't be) 'settled' is that those who write about tend to put their own field first, and use that as their vantage point. As someone who has studied the history and evolution of the planet, Bob Carter's credentials are as valid as anyone else's. So are Geoff Davies' credentials (he is also a geologist). But no one can claim to know it all, and to be omnicompetent.

Geoff Davies: I asked what I thought were central questions, and you have responded. I'll use your identifiers.

'First' — the models can't account for recent warming without human emissions. But that won't do. (i) How do the models account for the MWP? (ii) How do the models deal with the lack of warming over the last decade or so? (iii) In any case, as I have argued before, the models have to make large numbers of assumptions, whose validity is not clear. (iv) And models are never evidence of anything — they are exercises in playing with hypotheses and data.

'Second' — 'the warming signal would emerge from the noise early in the new century' Really? That is not what Hansen, Gore et all, let alone Jones et al, or any of the four IPCC reports, were saying. They said it was here now, and disastrous. Is 'noise' a way of describing natural forces or variation? And I'm not aware of any work that distinguishes human emissions form natural forces (whatever they are). This is really very vague.

'Third' — 'geological evidence' Here, as elsewhere, it seems to me that you like the evidence that fits your case and brush away the evidence that doesn't. I'm aware of the danger of doing this myself, which is why I remain agnostic rather than sceptical. But the geological evidence offers a number of possibilities, doesn't it? A huge (in human terms) lag time, and periods of high CO2 and low temperatures, make one wonder at the relationship, at least I do.

(more to come)

Geoff "My puzzle has been what people find emotionally threatening in the prospect of changing our lives a bit so as to be kinder to the planet, yada yada yada including the deliberate destruction or debilitation of many industries. It's OK to dump textiles, footwear, sugar, yada yada, but not coal. Ideology is the common thread. Free market, It would be interesting to know how many "sceptics" have right wing political views"

This is not climate science - it is environmental activism.

Confronted by skeptics of CO2 caused AGW, you flip into this realm of "Our petty little political fashions don't dictate reality, the Earth does."

It has nothing to do with this particular subject, you are off message and it appears you are a confused communicator.

My beef with the whole AGW debate is that AGW is used as a lever by environmentalists like yourself.

I have no problem with reduction in pollution, in all manner of 'kind to the earth" programs, we do these in our household constantly.

But I have real problem with being bullied with the CO2 AGW debate to get a result in socialized redistribution of wealth and socialized environmentalism. Copenhagen failed on this point.

Your motives and your arguments about being an activist and nothing really to do with science, just as qanda is more about politics and throwaway lines interspersed with insults.

I have a range of political views, depending on the subject at hand, not everyone is hard in one camp or the other, as you seem to think. I have some socialistic sympathies and also some hardline conservative tendencies when it comes to say, taxation.

If you want to get out a message on activism, fine, but now can you see why the communty is confused by climate scientists? You don't know the difference in your own pitch when it comes to AGW or envirnmental activism.

So get off the environmentalism from the AGW Climate Science Pulpit - you are bringing your personal beliefs and predjudices into a scientific debate, and self justifying doing that.

(final post)

Manipulation does worry me. I don't like the suppression of outliers in data. They are telling you something, perhaps that your instrument is not working, or that there is a chance blip, but the smoothing and averaging and adjustments that have gone on with 'av.glob.temp' always seem to point in one direction, and that doesn't fill me with confidence.

Natural fluctuations were not much talked about until now, where they have to be taken seriously, because, as Jones and Trenberth separately pointed out, the observations simply don't stack up well against the models. So, how much of current warming (if real) do you attribute to natural variations and how much to human emissions?

Mediaeval Warm Period. More equivocal data, all of them relying on proxies, and different proxies. But I've been to Fountains Abbey, not far below the Scottish border, and there you can see stone evidence of the vineyards and wine-making that went on there in the 14th and 15th centuries. There are a few vineyards in Kent today. That's about it. I haven't been to Greenland, but if there is a graveyard there that lies in permafrost, that would also tell us about the difference between MWP and today.

It seems to me, at least, that the evidence you point to is not compelling, and much of it is simply hypothesis. I've looked at all the papers about tipping points, and they are arguments for there being tipping points, not evidence, data, or observations that make such a hypothesis more than possible. You seem determined to see it your way, and you may be right. But not because of the current evidence.