It is a vision of a future so apocalyptic that it is hard to even imagine.

But, if leading scientists writing in one of the most respected academic journals are right, planet Earth could be on course for global warming of more than seven degrees Celsius within a lifetime.

And that, according to one of the world’s most renowned climatologists, could be “game over” – particularly given the imminent presence of climate change denier Donald Trump in the White House.

Scientists have long tried to work out how the climate will react over the coming decades to the greenhouse gases humans are pumping into the atmosphere.

According to the current best estimate, by the Intergovernmental Panel on Climate Change (IPCC), if humans carry on with a “business as usual” approach using large amounts of fossil fuels, the Earth’s average temperature will rise by between 2.6 and 4.8 degrees above pre-industrial levels by 2100.