When the dust settles on the latest report by the Intergovernmental Panel on Climate Change, scientists will be more certain than ever before about humans' effect on the climate.
Governments will be urged to take drastic action to cut climate change emissions.
And according to the BBC, the panel will say it is "95% certain that the "human influence on climate caused more than half the observed increase in global average surface temperatures from 1951-2010."
Although the report is not published until Friday, the fallout has already started, with both sides of the debate getting in pre-emptive strikes in the weeks leading up to its release.
But however persuasive the arguments in the IPCC study, it's safe to say it'll be a while before this lot switch to an electric car and hoist a wind turbine on their roofs: