I think Al Gore has done a great service in making global warming cool. He's basically taken it from a nerdy, almost ignored issue to making it what it is - namely, a problem.

When thinking about the future, it is fashionable to be pessimistic. Yet the evidence unequivocally belies such pessimism. Over the past centuries, humanity's lot has improved dramatically - in the developed world, where it is rather obvious, but also in the developing world, where life expectancy has more than doubled in the past 100 years.

If every country committed to spending 0.05 per cent of GDP on researching non-carbon-emitting energy technologies, that would cost $25 billion a year, and it would do a lot more than massive carbon cuts to fight warming and save lives.

Of course, the world is full of problems. But on the other hand it's important to get the sense... are we generally moving in the right direction or the wrong direction?

Winter regularly takes many more lives than any heat wave: 25,000 to 50,000 each year die in Britain from excess cold. Across Europe, there are six times more cold-related deaths than heat-related deaths...by 2050...Warmer temperatures will save 1.4 million lives each year.

The second thing is, if you want to do something about global warming, you have to think much more long-term. There is something wrong with saying we should start using renewables now, while they are still incredibly expensive.

We've had the U.N. for almost 60 years, yet we've never actually made a fundamental list of all the big things that we can do in the world, and said, 'Which of them should we do first?'