Failure to take action to combat climate change will cause environmental catastrophe and cost the global economy US$20 trillion a year by the end of the century, the pressure group Friends of the Earth said yesterday.
In a report based on research from more than 100 scientific and economic papers, the group says that allowing global warming to continue unchecked will mean a temperature rise of 4oC by 2100, causing economic damage worth up to 8 percent of global GDP.
The study coincides with research from the oil group Shell yesterday, which said the need to find solutions to climate change could create a ?30 billion (US$56 billion) market for British business over the coming decade.
Shell's chairman, James Smith, said: "We do have to tackle climate change and that's a matter for government, companies and individuals as well, because the costs in the coming years from rising sea levels, from floods and extremes of climate will be too high.
"The cost-benefit equation of action to tackle climate change is favorable. That's true not just for the UK but internationally as well," he said on the BBC Radio 4.
Both reports were released ahead of the British government's own review of the economics of climate change carried out for the Treasury by Sir Nicholas Stern. That is expected to be published later this month and is likely to conclude that the costs of tackling climate change are far more modest than had been thought.
The Friends of the Earth report was compiled by economists at the Global Development and Environment Institute at Tufts University in Massachusetts in the US. Institute director Frank Ackerman said: "The climate system has enormous momentum, as does the economic system that emits so much carbon dioxide. Like a supertanker, which has to turn off its engines 25km before it comes to a stop, we have to start turning off greenhouse gas emissions now in order to avoid catastrophe in decades to come."
According to the report, global temperatures are already 0.6oC above pre-industrial levels and temperatures will rise by more than 2oC unless there are "immediate and vigorous efforts to reduce emissions," that a 3oC increase was "extremely likely without major efforts at reducing emissions," and the increase would be 4oC with "no efforts at reducing emissions."