Climate scientists warned the United Nations Climate Conference in Bali of the need to act immediately to cut greenhouse gas emissions, with a window of only 10-15 years for global emissions to peak and decline, and a goal of at least a 50 per cent reduction by 2050.

They stated that if immediate action is not taken, millions of people will be at risk from extreme events such as heat waves, drought, floods and storms, with coasts and cities threatened by rising sea levels, and many ecosystems, plants and animal species in serious danger of extinction.

The researchers have issued a ‘Bali Climate Declaration by Scientists’ in which they call on government negotiators from the 180 nations represented at the meeting to recognize the urgency of taking action now. They say the world may have as little as 10 years to start reversing the global rise in emissions.

Prof Corinne Le Quéré of the British Antarctic Survey said: “Climate change is unfolding very fast. There is only one option to limit the damages: stabilise the concentration of CO2 and other greenhouse gases in the atmosphere.

“There is no time to waste. I urge the negotiators in Bali to stand up to the challenge and set strong binding targets for the benefit of the world population.”

The Bali Declaration states that long-term greenhouse gas concentrations need to be at a level well below 450ppm CO2e (450 parts per million measured in carbon dioxide equivalent). The declaration calls on governments to reduce emissions “by at least 50 per cent below their 1990 levels by the year 2050.”

The Bali Declaration states that every effort must be made to keep increases in the globally averaged surface temperature to below 2 degrees C and that “to stay below 2 degrees C, global emissions must peak and decline in the next 10 to 15 years”.

The critical reductions in global emissions of greenhouse gases and the atmospheric stabilisation target highlighted in the Bali Declaration places a tremendous responsibility on the Bali United Nations Framework Convention on Climate Change and must include the vast majority of the nations of the world.

“As scientists, we urge the negotiators to reach an agreement that takes these targets as a minimum requirement for a fair and effective global climate agreement.”