If you measure the significance of a topic by how much media attention it receives, I would guess that last year climate change came close to ousting the Iraq war as the number one issue. And as the new year stretches ahead of us on this first weekend of January, I am sure that the future of the planet - in particular the seemingly unstoppable rise in greenhouse gas emissions - will dominate our press and television.

The event that truly triggered the rising wave of concern with global warming in this country was the publication in October of the Stern Report on Climate Change. Sir Nicholas Stern, a former World Bank chief economist, pointed out that climate change could shrink global economies by 20 per cent; world temperatures were likely to rise by 2°C by 2050, or sooner; up to 200m people could become refugees through flooding or drought.