The Yellowstone volcano is one of the few dozen volcanoes on Earth labelled a supervolcano for its ability to expel more than 250 cubic miles of ash and debris. The plumes from such eruptions can rise 17 to 30 miles into the atmosphere, above the cruise-level of jets and can cause devastation on a global level. This type of event has occurred three times in history: 2.1 million years ago, 1.3 million years ago and 630,000 years ago.
Larry Mastin, a USGS Hydrologist, worked with fellow colleague Jacob Lowenstern in 2016 to produce a paper on the ash-fall impacts in the event of another supereruption.
Speaking during a public lecture the same year, he explained: “The objective was to see how the growth of umbrella clouds would affect ash distribution from Yellowstone.
“We did a few dozen simulations starting with an erupted volume of a few hundred cubic kilometres of magma.
“So this is – if you consider the volume of tephra that expands as it erupts – the volume of the tephra blanket that forms would be a few times greater than that of the magma alone.
A simulation of Yellowstone volcano activity in the month of July (Image: USGS/GETTY)
Larry Mastin is a USGS Hydrologist (Image: USGS)
So in these simulations you can see, that over a three-day period, this umbrella cloud covers most of the North American continent
“So this would be comparable to a tephra volume over 1,000 cubic kilometres.
“We used a duration that ranged from three days to one month and an umbrella cloud height that ranged from about 15 to 35 kilometres (nine to 18 miles).
“The wind fields were randomly chosen from historical patterns, but turns out they are actually not that important.”
Mr Mastin then demonstrated how a Yellowstone supereruption would bury the majority of North America in ash, with some regions more heavily affected.
He detailed how the duration of the eruption, or the time of year seemed to make little change on its consequences.