Climate change 'brings huge cost'
But taking action now would cost just 1% of global gross domestic product, economist Sir Nicholas Stern says.
Without action up to 200 million people could become refugees as their homes are hit by drought or flood, he adds.
Chancellor Gordon Brown is to promise the UK will lead the international response to tackle climate change. < !-- E SF -->
n is to say of the government-commissioned report: "The truth is, we must tackle climate change internationally, or we will not tackle it at all."
The Prime Minister, writing in The Sun newspaper, said the review was the most important report he had received during his period in office.
He said Britons were keen to lead the way in saving energy, but the problem needed to be tackled globally not just domestically.
The Stern Review, which is published on Monday, will say the key to solving the crisis is getting the big polluting countries, such as the US and China, to cut their emissions.
Sir Nicholas will say the polluters must be made to "pay the price" for the problems they are causing the planet.
The report warns unless the world moves to cut green house gases it is heading for a "catastrophic climate change" which would create the worst global recession ever seen.
The Stern Review forecasts that 1% of global gross domestic product (GDP) must be spent on tackling climate change immediately.
It warns that if no action is taken:
- Floods from rising sea levels could displace up to 100 million people
- Melting glaciers could cause water shortages for 1 in 6 of the world's population
- Wildlife will be harmed; at worst up to 40% of species could become extinct
- Droughts may create tens or even hundreds of millions of 'climate refugees'
The study is the first major contribution to the global warming debate by an economist, rather than a scientist.
Already Environment Secretary David Miliband is considering a range of taxes designed to change people's behaviour to offset global warming.
And Mr Brown has recruited former US vice president Al Gore as an environment adviser.
Meanwhile, the Conservative Party said it was examining the possibility of taxing air travel.
BBC environmental analyst Roger Harrabin said some economists say climate science is so uncertain that we should not spend huge amounts now to cut emissions.
However the review says failure to act early could end up costing between 5% and 20% of global GDP and render large parts of the planet uninhabitable with poor nations hit first and hardest.
Africa is likely to be most harmed by climate change and Sir Nicholas says we have a "moral duty" to cut emissions.
Switching to cleaner energy sources, like wind and solar, can help us avoid the worst of the damage, the report adds.
Green taxes and changing behaviour will help reduce the effect of climate change - but any schemes should encompass the globe, it continues.
Unilateral moves would not be enough, says Sir Nicholas. For example, if the UK shut down all of its power stations tomorrow, the reduction in global emissions would be wiped out in just over a year by increased emissions from China.
'Urgent deal needed'
The review calls on the international community to sign a new pact on greenhouse emissions by next year rather than in 2010/11, when they had planned to agree a successor to the Kyoto agreement on cutting carbon dioxide and other gas emissions.
Even if immediate action is taken to cut pollution, slow acting greenhouse gases will continue to have an effect on the environment for another 30 years, it adds.
Action groups and development agencies have welcomed the review and urged the government to take action to protect poor countries from the effects of climate change.
"Poor communities, who have contributed least to climate change, are suffering the most from its effects. Current efforts to respond to climate change are simply not urgent enough," said Tearfund Advocacy Director, Andy Atkins.資料來源：BBC http://news.bbc.co.uk/1/hi/business/6096084.stm