On current projections, global emissions of CO2 will plateau at around 50 billion tonnes during the coming decades, putting the world on course for changes to the climate that are way beyond the experience of modern civilisation.
As ministers join negotiators from around the world for the UN climate talks in Doha, Qatar, environmental experts have warned that countries were acting as if change was too difficult and costly, while delay did not pose any problems.
The paper by Lord Nicholas Stern (who wrote a review into the economics of climate change in 2006) and colleagues at the Centre for Climate Change Economics and Policy and the Grantham Research Institute on Climate Change and the Environment, said rigidity at the UN talks and the behaviour of negotiators was hampering progress, while vested interests remained powerful.
But they said accelerating the pace of changing to a low-carbon economy was both feasible and crucial.
They also warned that in order to keep global temperature rises to no more than 2ºC, considered to be the point beyond which the world would experience dangerous climate change, action to cut emissions was also needed from developing countries even if rich nations cut their greenhouse gas emissions to zero.
The experts warned there was a deep inequity in that poor countries would be worst hit by climate change while developed countries had benefited most from high-carbon growth.