This disaster is not set to happen in some science fiction future many years ahead, but in our lifetimeI think that there is plenty of evidence that temperatures are rising. Things like the fact that of the highest temperature summers on record in the UK, four or five have been in the last 10 years. Things like record sea temperatures in the tropics.
I think that this is likely to lead to more chaotic weather systems - El NiƱo recurring, exceptional hurricane years in the Caribbean like 2005 (though obviously this year hasn't seen anything like the same number), failure of monsoons, and droughts.
On the other hand, it is quite possible that this is fundamentally a cyclical change - that the human impact on the climate is marginal. It's possible that as the temperature rises, the cloud cover and vegetation levels will increase, providing a feedback system. It's conceivable, as suggested in a BBC Horizon programme, that the rising temperature will switch off the Atlantic Conveyor, causing a subsequent catastrophic fall in temperature. I'm neither of the apocalyptic camp, nor of the capitalist, laissez-faire camp, because I don't have enough information.
So what do I think we should do? Fundamentally, in my opinion, it comes back to theology. If humans are supposed to be stewards of creation, then we are to use the resources we have wisely. That means being careful about our use of limited resources, and doing what we can to protect the world about us - minimising our footprints, if you like. I don't think it means we have to be vegetarians - the Bible suggests that there is a divide between humans and animals which is reflected in their different nature (for example, with the exception of cats, few creatures attempt to organise humans ...), and that God specifically gave animals to humans for their "use" - but I do think we aren't free to abuse animals. I was also shocked to discover that, according to The Rough Guide to Ethical Shopping, it takes 100,000 litres of water to produce 1 kg of beef. I'm not opposed to nuclear power - but as with any form of power generation or industry, thought has to be given to the impact throughout its life - from construction to decommission and decontamination.
So that's it really. I believe that we should be careful about how we use resources not fundamentally for fear of climate change but because it is our job to take care of a limited resource.