THE world will warm by 3C, even under the most optimistic emissions projections for 2050, according to the UN group that studies global warming. The increase, which would cause drought and famine for 400 million people and devastate wildlife, is predicted by the Intergovernmental Panel on Climate Change in its most confident assessment yet of how greenhouse gases are affecting global temperatures.
A draft of part of the panel's fourth report, which the US Government has released on the internet, shows that it has, for the first time, placed a likely figure on the progress of global warming, indicating a degree of scientific certainty that it has avoided in the past.
It says that temperatures could increase by between 2C and 4.5C when atmospheric carbon dioxide reaches double the pre-industrial level, but it declares 3C to be the "most likely value" for such change. A 3C rise is the level at which a British Meteorological Office conference last year judged that "dangerous" climate change would occur.
Previous reports from the IPCC, a traditionally cautious body, have given only wider ranges of possibilities, which it acknowledged to be highly uncertain.
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