With the UN conference on climate change now under way in Nairobi, with new reports of Rupert Murdoch having a change of heart on climate and now calling for a new global treaty, and with reports that Governor Arnold Schwarzenegger is taking California down the most aggressive climate change strategy in North America, there are signs that business has realised that global warming is a market issue.

One of the catalysts of course was the Stern review on the economics of climate change. Released by the Blair Government at end of last month, the report comes across in parts as a salvo at the Bush administration.

Despite the interest from business, there is still a long way to go and I examine some of the problems in this article here.

It's one thing to talk about business doing something to fix the problem. But costs, like a carbon tax, would be passed on to consumers. One question is whether they would accept it. Another is whether Governments would take that risk.

No simple solutions here. Tackling climate change means that we have to change, says UN Secretary General Kofi Annan.