i wouldn't say there's no reason to claim global warming is happening when it's not (plenty of companies are jumping on the bandwagon), but there are an awful lot more financial reasons to claim it's not, if you ask me.
This is the interesting one - how many companies have jumped on the Green band wagon for fear of losing sales by not being perceived as being environmentally friendly? It bugs the hell out of me to see car companies and airlines claiming to be 'Green' - sure, you can be less polluting than you were, but they are a long way from being environmentally friendly, however you look at it.
On the scientific stuff - problem is that we don't have any accurate data which goes back far enough to draw any logical conclusions - and you don't want to be an enviro-sceptical boffin, because you will get your funding withdrawn from the government who is busy collecting green taxes. My conclusions are pretty much with Johnny Mac:
1. Is climate change a fact of life? - Yup
2. Is our consumption of Earth's raw materials contributing to this? - Probably
3. Will going Green reverse climate change? - No
4. Is going Green still a valid thing to do in order to conserve scarce resources - Yes
In my view, (and apologies if I offend anyone) - the one biggest thing that the world could do in order to slow down 4 is to control population growth - in 1950 there were about 2.5 Billion people on Earth - we now have more than 6 Billion!! - so we should be doing everything we can to REDUCE this number, rather than letting it increase. I'll stop before I get on my really radical soap box about this one.....