A huge volcano in the US would have catastrophic worldwide consequences if it erupted, potentially killing millions and sparking the next ice age.
Found in the state of Wyoming, the supervolcano in Yellowstone National Park was formed by an eruption 640,000 years ago and is one of the largest in the world at a huge 30 by 45 miles.
It has only had three eruptions over the past two million years with the last one taking place 631,000 years ago, according to experts.
Should the supervolcano erupt any time soon, millions would die almost instantly and the repercussions would be felt for decades.
Professor Michael Branney, a volcanologist at the University of Leicester, previously warned Yellowstone could erupt at any time.
He explained: “Yellowstone will erupt again, but it is not known when this will happen or on what scale.
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"Volcanoes do not erupt according to a timetable or schedule, and the next major eruption could be far away in the future.”
The magma building under Yellowstone would be one of the most dangerous parts of any future eruption.
Not only would there be hot molten lava pouring onto the Earth below, but magma would also be shot out into the sky becoming ash particles.
Yellowstone's sheer size means the ash would impact almost everywhere in the USA and Canada, making most of North America uninhabitable.
People within 1,000 kilometres of the eruption would be killed by the blast and its ash, resulting in the death of tens of millions.
The impact on cities and towns would also be devastating.
Just 12 inches of ash is enough to cave in roofs, so any buildings which are hit would be destroyed.
People outside of the 1,000 kilometre radius would not be safe either.
Scientists believe that any potential eruption of Yellowstone would reach as far as the east coast of the United States.
In the event of an eruption, the coast would be covered in 0.4 inches of ash.
This amount would be incredibly dangerous to human lungs and result in respiratory problems for millions.
Ash from Yellowstone could spread even further afield and reach parts of Europe.
One of the most concerning effects of the amount of ash particles in the air would be on the climate.
The ash would block out the sun causing the whole world to experience a sudden temperature drop of up to ten degrees.
It would even spark a mini ice age.
Temperature decreases could last for up to a decade resulting in numerous changes to the ecosystems on Earth.
This would devastate the environment and cause an instant change in weather systems globally.
A chain reaction would result in crops and the water supply being affected making it harder for humans to grow food.
However, fortunately an explosion on such a scale is considered to be extremely unlikely to happen any time soon.
