The break-up of a supercontinent may have caused a ‘Snowball Earth’.

The Earth might have been sent into an ice age by the break-up of a supercontinent 750 million years ago, creating a global snowball.

The break-up probably caused an increase in rainfall and weathering of rock, say climatologists. This would have sucked greenhouse gases out of the atmosphere and…

caused a run-away cooling effect. The mechanism could explain how the entire planet becomes encased in a mass of ice, as many researchers think it has done in the past.

The theory that the Earth was once completely frozen emerged in the 1960s, when scientists realised that global freezing could happen if the polar ice sheets grew above a certain threshold size. Because bright ice reflects sunlight and heat back into space, growing ice sheets cause further cooling. This feedback loop could tip the climate system into a deep freeze.

The planet could eventually thaw as carbon dioxide from volcanoes poking through the ice warm it.

In the late 1980s…

Full story here.