BBC HomeExplore the BBC
This page has been archived and is no longer updated. Find out more about page archiving.

17 September 2014
Accessibility help
Science & Nature: TV & Radio Follow-upScience & Nature
Science & Nature: TV & Radio Follow-up

BBC Homepage

In TV & Radio

Contact Us

You are here: BBC > Science & Nature > TV & Radio Follow-up > Programmes > Supervolcano
The world's biggest bang

A global disaster never witnessed by modern man may one day mushroom above the pine forests and hot springs of Yellowstone National Park in the United States.

While ordinary volcanoes can kill thousands of people and destroy entire cities, it's thought a supervolcano could claim up to a billion lives and devastate continents.

Ash tilts a jet photo: RL Rieger/USGS

Heavy stuff: Ash from the 1991 eruption of Mount Pinatubo in the Philippines settles on the tail section of a World Airways DC-10, causing it to tilt onto its rear wheels.

It's very likely a super-eruption would shutdown airports worldwide.

"A super-eruption is the world's biggest bang", says Prof. Bill McGuire of the Benfield Greig Hazard Research Centre at the University of London. "It's a volcanic explosion big enough to dwarf all others and with a reach great enough to affect everyone on the planet".

Considering their destructive potential, it's a good thing super-eruptions are so rare – the last one happened in Toba, Indonesia, about 74,000 years ago. Geologists think these eruptions take place about every 50,000 years, which suggests one is overdue.

About 40 supervolcanoes are dotted across the globe. There are two in Britain – one in Glencoe, Scotland, the other in Scafell in the Lake District. However, most supervolcanoes, including those in Britain, burned out long ago.

Yellowstone, located in the western state, Wyoming, is a dormant supervolcano, which means a major eruption could happen in the future. But before you get worried, it's important to remember that most volcano experts say a Yellowstone super-eruption is probably a long way off, or it may never happen at all.

Mt St Helens erupts photo: Austin Post/USGS

Super size: About 2.1 m years ago the Yellowstone supervolcano erupted 2,500 times more ash than Mount St Helens (pictured).

Read about the 1980 Mount St Helens eruption on BBC On This Day.

"It's far more likely, if there is an eruption, it'll be on a small scale, perhaps comparable to Mt St Helens," says volcano expert Prof. Steve Sparks of the University of Bristol.

Although they're called 'super', most people would have trouble spotting a supervolcano. Their main feature is a large magma chamber, which is an underground reservoir filled with flowing, hot rock under huge pressures.

Some stats on the Yellowstone supervolcano:

  • A super-eruption would equal the force of 1,000 Hiroshima atomic bombs exploding every second.
  • You could fit Tokyo, the world's biggest city, in Yellowstone's super-volcanic crater.
  • Three super-eruptions at Yellowstone appear to have occurred on a 600,000-700,000 year cycle starting 2.1 million years ago. The most recent took place 640,000 years ago – suggesting Yellowstone is overdue for an eruption.

Continue to page two and find out how much volcanic ash it takes to collapse a roof.

The US Geological Survey has more information about the Yellowstone supervolcano.

(The BBC is not responsible for the content of external websites.)

Back to Supervolcano homepage

 Elsewhere in Supervolcano

Supervolcano homepage

Read about the programmes.

Photo gallery
See dramatic scenes from the programme and download wallpapers for your computer.

Respond to a disaster
Play a game where it's your job to handle an eruption of the fictional Mount Spur.

 Elsewhere on

Horizon: Supervolcanoes
Read a transcript of the programme that inspired Supervolcano.

Natural disasters
Ten per cent of the world's population may live within volcanic danger zones.

Radio 4: Supervolcano
Listen as Peter Evans meets scientists studying the Yellowstone supervolcano.

Mount St Helens erupts
BBC On This Day has video and articles about the 1980 eruption of the famous US volcano.

 Elsewhere on the web

Yellowstone Volcano Observatory
The US Geological Survey has detailed information about the supervolcano.

Discovery: Supervolcano describes what is under Yellowstone.

Volcanoes and climate change
A NASA article explaining how volcanoes change the weather.

London Volcanic Ash Advisory Centre
London VAAC is one of nine international centres on the lookout for volcanic ash.

The Geological Society
An in-depth study of the effects of super-eruptions.

Volcano Live
Volcano news and information from expert John Seach.

Volcano World
A University of North Dakota site with information about volcanoes around the world.

How Volcanoes Work
A NASA sponsored site about volcano science.

What is ash?
The US Geological Society explains what to do if you experience volcanic ash.

USGS photo library
The US Geological Society has an extensive collection of geology photographs.

The BBC is not responsible for the content of external websites

Science Homepage | Nature Homepage
Wildlife Finder | Prehistoric Life | Human Body & Mind | Space
Go to top

About the BBC | Help | Terms of Use | Privacy & Cookies Policy