TOURIST SPOT TIMEBOMB THAT COULD KILL FIVE BILLION
Bubbling away beneath the Earth’s crust is a supervolcano so dangerous, its explosive power would bring ash clouds, acid rain and famine to Britain… and scientists fear it’s overdue an eruption
ATICKING timebomb beneath America is set to explode with the force of more than a thousand Hiroshima atomic bombs, sparking a global catastrophe. Some 70,000 people would be killed within minutes. Billions more could die in the ensuing drought and famine.
The skies clouded over with ash, temperatures worldwide would plummet by 15 degrees. Air travel would be impossible for months, possibly even years.
The global economy would collapse, plunging the world deeper into a humanitarian crisis. Britain would be stranded beneath endless dark skies and deluged with acid rain that would contaminate water, destroy crops and kill livestock – a catastrophe spreading across the Earth. There’s nothing we can do to stop it... and it could happen tomorrow.
That’s the shocking warning from the new Channel 5 documentary Doomsday Volcano, which airs tomorrow night.
More than 500 active volcanoes rumble menacingly across the world, yet the biggest threat to the planet is the “supervolcano” that lies beneath America’s famously picturesqueYellowstone National Park inWyoming.
“Potentially a supervolcanic eruption on the scale of Yellowstone could be a speciesending event,” says science writer Bryan Walsh, author of End Times.
One scientist predicts that five billion people could die in the aftermath of a Yellowstone supereruption, as ash-filled skies create a “volcanic winter” that devastates the global food chain. Yellowstone has experienced catastrophic eruptions three times in the past: two million years ago, 1.3 million years ago and, most recently, 640,000 years ago. Some scientists believe it is overdue for its next eruption.
“Geological history would tell us that Yellowstone in the future will have a big, big, catastrophic eruption again,” says Prof Christopher Jackson of Imperial College London. Prof John Grattan of Aberystwyth University agrees: “It’s inevitable, it will happen.”
One of the world’s largest geothermal regions,Yellowstone lures millions of tourists a year to admire its majestic mountains, valleys and streams where elk, bison and grizzly bears roam. Its natural wonders feature one third of the world’s hot geysers, including Old Faithful, which regularly shoots boiling water up to 185 feet high.
There are more than 10,000 hot springs in the park, including one of the world’s largest, Grand Prismatic Spring, with its striking rainbow-coloured reflections. But beneath the awe-inspiring landscape lurks one of the world’s most dangerous supervolcanoes.
A supervolcano is one that has already experienced an eruption of magnitude eight – the maximum possible – on the Volcanic Explosivity Index. Yellowstone’s past eruptions and the ensuing volcanic winter caused by global clouds of ash devastated early life on Earth.
BUT MODERN humans have only been around for about 200,000 years, and a new supereruption could bring an unprecedented Armageddon. “It would look like hell on Earth,” says Prof Jackson.
A remnant of the last cataclysm is one of Yellowstone’s most dramatic features: a caldera 45 miles across: the crater left when the volcano collapsed after spewing its magma into the atmosphere. Yellowstone is unusual in that it now has not one, but two gargantuan magma chambers churning with molten hot rock beneath the caldera, extending 50 km below the surface.
“We’re talking about 3,000 to 11,000 cubic miles of material under there,” says Prof Jackson. “That is jaw-droppingly huge.”
A supereruption could shoot five million tons of molten lava, rocks, ash and gas into the atmosphere every second for weeks or
months, scientists estimate. The eruption of Mount Vesuvius in 79 AD, which saw thousands buried alive in ash before they could flee, was small in comparison.
A Yellowstone supereruption would cause devastation on a horrifically larger scale.
“One could conceive of pyroclastic flows, which are hurricanes of superheated volcanic ash, travelling across the landscape at several hundred miles an hour, potentially for a thousand miles or more, and it’s 400 degrees Centigrade, burning everything in its path,” says Prof Grattan. “If you’re in its way you’re going to die.”
The eruption’s initial blasts could flatten seven US states “like a nuclear bomb”, and “significantly cool the planet for years on end”, claims the documentary.
Geological evidence from Yellowstone’s past eruptions suggest that ash would cover America from coast to coast. A US Geological Survey (USGS) study in 2014 predicted that 70,000 residents living in the vicinity of Yellowstone would not survive the immediate cataclysm. Cities like Billings in Montana, and Casper in Wyoming, could be buried beneath a metre of burning ash. Los Angeles, New York and Washington, DC, would be carpeted with ash, potentially devastating agriculture across the continent. The global climate could be dramatically impacted for “years to decades”.
The 2010 eruption of Icelandic volcano Eyjafjallajökull sent clouds of ash and dust into the sky that grounded air travel across Europe and North America, cancelling more than 100,000 flights and stranding millions of passengers for days.
A Yellowstone supereruption would be far more destructive.
“If Yellowstone does its worst, it could mean no planes in the skies for months, or even years, the world’s economy brought to a complete halt,” claims the documentary. Volcanic sulphur clouds would combine with atmospheric moisture to create sulphuric acid – acid rain – that coupled with ash-filled skies could kill wildlife, livestock and crops across the planet. Disturbingly, modern science has no way to prevent such a cataclysm. Drilling down into the supervolcano’s magma to relieve the pressure is not an option, apparently, since minerals quickly crystalise to block any drilling holes. The USGS warns: “Research has proven again and again that depressurisation is one of the factors that drives magma toward the surface to erupt.” That doesn’t mean researchers aren’t trying to find ways to warn the planet of impending catastrophe.
YELLOWSTONE is one of the most closely monitored volcanoes in the world. Satellites scrutinise the surface of Yellowstone to measure every millimetre the Earth rises as magma pressure builds beneath, while seismographs and GPS stations measure ground movement, sample gasses and water chemistry, and scientists track gravitational fluctuations as subterranean mass increases. Yet the USGS predicts that when Yellowstone next blows, it is unlikely to be a supereruption.
“The most likely explosive event to occur at Yellowstone is actually a hydrothermal explosion – a rock-hurling eruption – or a lava flow,” states the agency. “Hydrothermal explosions are very small… and form a crater a few metres across.” But Yellowstone lava flows of molten rhyolite are nothing to sneeze at. Yellowstone’s chief scientist Mike Poland says: “They can have flow fronts that are basically cliffs which are 450 feet high.”
Reassuringly, neither earthquakes nor a nuclear bomb could trigger a supereruption, say USGS scientists. In fact Yellowstone is routinely shaking: it registered 267 quakes in October. It is certain to keep rumbling, its subterranean forces mounting like a pressure cooker, while visitors continue to enjoy the raw beauty of a natural landscape still being carved out over millennia.
Should the world be worried? At present, the USGS insists: “The threat of an eruption remains low.” But real danger remains. “There are no indications at the moment that the magma chamber below Yellowstone is cooling down and settling down, so there is a potential for a supervolcanic eruption,” says Prof Grattan. One thing is certain: sooner or later, Yellowstone’s supervolcano will blow.
“Whether we’re here to see it is a different thing entirely,” says Prof Jackson. “But it’s likely to happen again.”
‘At its worst, an explosion would mean no more planes in the sky for months or years, the world’s economy halted’
●●DoomsdayVolcano: The Next Pompeii is broadcast tomorrow at 10pm on Channel 5