Here in the UK, Channel 4 just screened an interesting documentary: The Great Global Warming Swindle. Good viewing and challenges what seems to have become the accepted view that global warming is caused by man-made CO₂ emissions. Instead, the programme points out that climate change has always been with us (including a medieval warm period, even balmier than today, and a mini ice-age in the seventeenth century when the River Thames froze so solid that fairs were regularly held on the ice). The programme presents some evidence to suggest that the rise in carbon dioxide lags behind temperature rises by 800 years and therefore can't be the cause of it. It also suggests that man-made sources of carbon dioxide are dwarfed by natural sources and that the source of variation in temperature is really linked to variations in sun activity.

The programme suggests that we can hardly be surprised when "environmental journalists" whose continued employment requires publication of stories produce newsworthy doom-laden stories. After all, why would the media publish stories from such journalists the gist of which is there is no need to panic because climate variation is nothing to do with us.

Anyway, if you are able, see the programme again in the UK on More4 (Monday 12 March 2007, 10.00pm): "Polemical film challenging the consensus that man-made CO2 is heating up the earth. Featuring leading academics, the film questions the science behind the accepted reasons for global warming and argues other explanations for climate change are not being properly aired".