Science Story

02 December 2008 23:43 BST

'Act now' to prevent climate change

A powerful report on the effects of climate change on the world economy today warns that global warming could cost the Earth 20 per cent of its wealth if the problem is not dealt with soon.

The Stern report, conducted by the former chief economist of the World Bank, Sir Nicholas Stern, and commissioned by chancellor Gordon Brown, urges the world to spend one per cent of the global gross domestic product (GDP) in combating climate change now.

This spending would amount to around £184 billion, but is said to be able to prevent a drastic shrinking of the world's economy by a predicted £3.68 trillion.

Stern's conclusions warn that unabated climate change risks raising average temperatures by over 5C from pre-industrial levels, leading to a transformation of the physical geography of our planet.

The report also warns of mass migration of the world's population as 200 million could become refugees with their homes destroyed by rising water levels.

If the problem of climate change is to be tackled, the report adds, then the big polluters of the world such as China, India and the US need to take steps to reduce carbon emissions.

Announcing his report, Sir Nicholas said: "The conclusion of the review is essentially optimistic. There is still time to avoid the worst impacts of climate change, if we act now and act internationally.

"Governments, businesses and individuals all need to work together to respond to the challenge. Strong, deliberate policy choices by governments are essential to motivate change."

He added: "But the task is urgent. Delaying action, even by a decade or two, will take us into dangerous territory. We must not let this window of opportunity close."

Speaking at the launch of the report at the Royal Society, the prime minister Tony Blair said that it "offers a stark warning but also hope that this challenge can be tackled".

Although he said that individuals must be encouraged to take action, Mr Blair placed an emphasis on the need for global collaboration, saying: "The review sets out a framework for international action.

"It is only international action that will tackle the problem. What is absolutely clear is that we have to be bolder at home, in Europe and internationally."

He added: "Investment now will pay as back many times in the future. Should we fail to address this challenge I don't think we will be able to excuse ourselves to future generations."

Speaking after Mr Blair, the chancellor Gordon Brown announced a number of initiatives to work with other countries to reduce emissions and said that both public and private investment in low carbon technologies are vital in reducing climate change.

The government will legislate for a climate change bill, he added, and will establish an independent body to advise it on global warming.

Responding to the report, Tim Yeo, chairman of the Commons environmental audit committee, described it as "wholly welcome" and Andrew Simms, policy director at the New Economics Foundation said that he "welcomes what feels like a real political turning point".