Anyone who has seen Al Gore's fantastic documentary An Inconvenient Truth will be as dismayed as I am to see the supposedly respectable BBC publishing a report from supposedly respectable scientists which claims that "Global climate change is 'very likely' to have a human cause". The link between human activity and climate change is not "very likely", it's "fact". The evidence is overwhelming. To imagine otherwise is like claiming that the pope is "very likely catholic" and bears "very likely" shit in the woods.
Doubt, as generated by phrases sure as "very likely", is the greatest weapon of the pro-polluting lobby. Just like the tobacco lobby used to claim it was just "very likely" that smoking could affect your life expectancy.
On the subject of the latter, I have given up again. Ouch.