Campaigners have demanded the world moves away from using fossil fuels, ahead of a major international report by the UN's Intergovernmental Panel on Climate Change.
The latest report will set out ways to curb rising temperatures by tackling greenhouse gas emissions.
The third of a trilogy, the study comes just two weeks after the second part of the report warned that the effects of rising temperatures were already being felt across the world.
It said that without action climate change would increasingly threaten security, health and food supplies, exacerbate poverty and damage species and habitats.
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