The far-reaching damage

But the destruction close to the volcanoes would just be the beginning.

The eruptions would send plumes of volcanic ash into the sky that could travel for thousands of miles.

Dr Watson said: 'Ash is pretty unpleasant stuff. Its comprised of tiny fragments of glass, crystals and rock.'

Pyroclastic flows, are fast-moving clouds of rock, ash and gas that are very hot - with temperatures rising up to 1000 degrees centigrade. Pictured here, a pyroclastic flow from Mount Oyama on the island of Miyakejima, some 200 kilometers south of Tokyo, heads into the sea

You may remember the worldwide flight cancellations caused by the 2010 eruption of Eyjafjallajökull in Iceland, in the fears of damage to airplane engines.

As well as the potential damage to engines, volcanic ash is so heavy that it could actually collapse buildings, by piling up and slowly sinking the foundations.

Breathing in ash can cause massive problems to our lungs, including silicosis, and damage that sends our immune systems into overdrive, leading to a range of secondary problems.

Essentially, there would be no buildings, no vehicles run by an engine, and you would not be able to go anywhere without a gas mask.

To add to this, communication channels would be out of the question - ash can disrupt satellite dishes and block radio waves.