The Stern Review, a government-commissioned report on climate change, is set to warn that unchecked global warming could shrink the world economy by as much as 20 per cent, or £3.68 trillion.
Sir Nicholas Stern, former chief economist of the World Bank, says one per cent of that sum must be spent, now, to combat climate change and cut global carbon emissions.
Gordon Brown is expected to respond to the report by championing more emissions trading, and by employing old mate and ex-US vice president Al Gore as an adviser on green issues.
Tony Blair, meanwhile, has taken steps to alert the public by setting out the main points of the report in The Sun.
Brown will propose that the EU commit to targets of a 30 per cent reduction in carbon emissions by 2020, and a 60 per cent reduction by 2050. He wants to see the embryonic European carbon trading scheme extended and linked to other markets, such as California.
However, the Stern Report identifies the US and China as key to halting climate change. Without getting two of the most polluting economies on board, carbon cuts in the UK will be swamped by increases elsewhere.
Stern paints a bleak picture. He warns that the "catastrophic climate change" for which we are heading will create hundreds of millions of refugees. One hundred million could be displaced by rising sea levels alone.
As many as 40 per cent of species could go extinct, and up to one in six people will face severe water shortages as a result of melting glaciers.
To tackle the economic crisis he foresees, Stern asks the international community to agree on a successor to Kyoto next year, rather than waiting till 2011 as originally planned. He describes it as our "moral duty" to reduce emissions, as failure to do so will hit the poorest nations of Africa first, and hardest.
The Stern Review is the first assessment of the likely impact of climate change produced by an economist, rather than from within the mainstream academic community. ®
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