For the first time, the U.N-backed Intergovernmental Panel on Climate Change says the use of fossil fuels – coal, oil and gas – will need to be “phased out almost entirely” by the end of the century.
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The IPCC’s latest report, released in Copenhagen Sunday, warns of “severe, pervasive and irreversible impacts for people and ecosystems,” if action is not taken to reduce emissions of carbon and other greenhouse gases (GHGs) globally – with a target of zero by 2100.

It declares “with greater certainty” than four other major assessments released since 1990, that human actions – “emissions of greenhouse gases and other anthropogenic drivers” – are chiefly responsible for global warming measured since the middle of the 20th century.