Leigh Jackson, I'm not certain what is your reason for commenting here.

"Half of the harm that is done in this world
Is due to people who want to feel important.
They do not see the harm - or they justify it
Because they are engaged in the endless struggle
To think well of themselves."

Well, I think man DOES affect the climate throu various means. Land use, land change, emmissions, and so on. I am in the 97% right?

The question should really be 'how much does man affect climate versus natural variation', and maybe there would be far more easily defined divisions.

I'm glad this thread has resurrected itself. It gives me a chance to gather my thoughts.

In answer to Richards question I think:

* Tyndall/Arrenhuis is repeatable good science
* however, it is lab science that falls over when it gets to the climate system, this is self evident.
* other factors can overwhealm the forcing when it is in a complex system as witnessed by the slowing/stopping we have seen
* other factors could be albedo, negative feedbacks from other atmospheric components, or variations in energy input or things we haven't even thought of yet.
* it would be odd if we didn't affect the climate in some way either by land use or input into the atmosphere. Anyone who denies this deserves the denier label
* modelling a multi-input chaotic system is futile, if you think you can do it I'll have next weeks lotto numbers now please
* the divergence between the models and observations gets wider month on month anyone who denies that deserves the denier label
* science has not been ready enough to defend itself when scientific results have been spun
* confirmation bias and noble cause have played their part
* politico-economic pressure has played its part
* tenure, grant money and pressure to publish have played their part
* Agenda 21 has played its part, especially in the UN involvement
* using the models for policy decisions even when we know there is a divergence is reckless and leads you down the Kev Henderson fallacy that to meet model predictions the temperature is going to have to do something way outside the realms of possibility
* growing uncertainty means that closes the validity gap rather than increasing the validity of a particular course.
* deriving a global temperature before satellite data is never going to give anything but huge error bars
* however, the case for 97% was not proven by cook's paper. His methodology and data handling are highly suspect.
* the perversion of the paper has been irresponsible but on the other hand Cook's lack of response to misrepresentation by politicians and media makes him complicit in the deception
* the concept of
* future generations are best served by passing them a vibrant economy and wealth. CO2 reduction policies will pass a broken economy that is pre industrial revolution except for countries who are willing to put their future over the requirements of the undemocratic UN
* people are catching on. Activists have almost warn out the cry of 'wolf'
* politicians are starting to catch up with the voters. More green giveaways from already empty coffers will eventually get them the sack.

So now you know ;)