Don Aitkin,

Excellent post. It's great to get some objective analysis from time to time.

The temperature projection models are one thing. But the analyses of costs and benefits of warming are an entirely different matter. So far, many people assume warming is bad. But is it really? There seems to be a growing realisation that warming is more good than bad up to around 2.2 C above present temperatures (i.e. up to about 3C above pre industrial temperatures):

http://www.lomborg.com/sites/default/files/Congress_testimony_April_2013_3.pdf

http://www.spectator.co.uk/features/9057151/carry-on-warming/

It is clear that the judgement of the people is correct - as it usually is - there is no justification for wasting enormous sums of money and damaging human wellbeing now, for the sake of an unfounded and poorly supported belief in catastrophic climate change. The evidence for catastrophic or dangerous climate change is weak to non existent.

Hi Leslie,

You ask << Is it possible to establish one basic "fact": that the polar caps are melting? >>

This may help you.

http://nsidc.org/arcticseaicenews/

Spindoc...typical obfuscation from your "denial world";

The NIPCC you quote is funded by the coal & gas industry sponsored Heartland Institute and according to the Heartland 2012 budget plan, the purpose of the NIPCC report is to critique the IPCC report. Also according to the Heartland 2012 Fundraising Plan, its ultimate purpose is to create a rebuttal to the IPCC report.

In short, the purpose of the IPCC report is to accurately summarize the most up-to-date state of climate science research and understanding, whereas the purpose of the NIPCC report is to try and poke holes in the IPCC report (unsuccessfully, as can easily be found via online search).

Second, unlike the IPCC report, the scientists contributing to the NIPCC report are paid for their efforts. The overall Heartland budget for the NIPCC reports from 2010 to 2013 is nearly $1.6 million ($388,000 in both 2011 and 2012), with $460,000 going to the lead authors and contributors ($140,000 in both 2011 and 2012). The 2011 Interim NIPCC report has 3 lead authors (Craig Idso, Fred Singer, and Robert Carter) and 8 contributors (Susan Crockford, Joe D'Aleo, Indur Goklany, Sherwood Idso, Anthony Lupo, Willie Soon, Mitch Taylor, and Madhav Khandekar), most of whom also receive a monthly salary from the Heartland Institute.

Compare to the IPCC where none of the reports are paid for nor does the IPCC receive funding for a predetermined result, merely funded by governments world wide to collect, summarize and present the work of qualified scientists.

So your quoted "evidence" is a fiction of course. I guess you have to post somewhere as I note the global newspaper industry (Murderocracy excluded) are refusing to accept denial drivel from your team anymore.

And all of the "denier" posts here are flawed by citing or inferring errors in modelling.

The existence of AGW is not predicated on modelling but global observational data and analysis. The modelling that the author and his cohorts are fond of belittle is used to predict the likely or possible future effects of the dramatic changes being exhibited. Clearly one can not say foe example, that the melting Greenland ice cover is going to raise sea levels by x meters without trying to model how much ice will be converted to water; just because it is being modeled does not mean the ice is not melting.

"I doubt there are many sceptics who would disagree with climate change."

I seem to be reading from a lot who accuse anyone who says he knows it is AGW, that it is anything from a plot by all the worlds scientists ( who ever managed that should be signed up to run the government he is such a good organiser)
and a conspiracy to steal from the "people" though quite how this works I cannot see.
So the number of sceptics who believe in climate change is pretty thin on the ground.

Leslie and Peter King
Is it possible to establish that the polar caps are melting? Yes and no.. for most people melting means change in the arctic sea ice which has recently been at historical lows during the Northern summer, but its not the actual cap.. there is no particular evidence that this trend is continuing as one of the links to the US National Snow and Ice Data Center shows. Is the cap itself melting? You'll see some evidence about this around - but I think you'll find the most pessimistic assessment (assuming any melting is occurring)still has the northern cap around for some time to come..

Every now and then you'll hear reports of chunks of the Southern ice cap falling off but it seems to regrow. Any overall shrinkage would be hard to prove.. I don't think there is any convincing evidence..