The supervolcano next door

The horrific deaths of 16 tourists on White Island, New Zealand, are a reminder of the lethal force of volcanoes.

White Island

Lillani Hopkins, a 22-year-old student, witnessed the eruption. She was on a boat leaving the island when it blew. Clouds of scalding hot water and ash descended on those tourists still on the island. Twenty three of the tourists from the island were taken to Lillani’s boat where passengers frantically attempted to treat them. They were in bad shape.

Lillani had never seen anything like it. Welts and burns that covered every inch of exposed skin. People’s faces coated in grey paste, their eyes covered so they couldn’t see, their tongues thickened so they couldn’t talk. Some of them still screaming. The boat appeared to be filled with discarded grey rubber gloves. But they weren’t gloves, they were husks of skin that had peeled away from people’s bodies (Globe and Mail, December 11, 2019).

Most of those who survived the eruption at White Island on December 9 suffered burns and 28 patients remain hospitalized, including 23 in critical condition. Hospitals are calling on international skin banks for the large quantity of grafts required.

Lillani’s chilling eyewitness account reminds me of the victims I saw in Pompeii, Italy. When Mount Vesuvius erupted in AD 79, plumes of scalding mud covered citizens. I remember one statue-like victim in particular, sitting on the ground, hands covering face, entombed for eternity in a thick crust of ash.

You don’t have to be standing on the rim of an active volcano to feel its affects. I still remember waking up on May 19, 1980, in Calgary the day after Mount St. Helens, Washington, erupted killing 57 people. Even though the volcano was 800 km away, there was a deposit of ash on my car.

The most powerful eruption in recorded history was at Mount Tambora in present-day Indonesia. Most of the deaths that resulted were not from burns but from climate change –the 92,000 fatalities were largely from starvation. The ash from the eruption was dispersed around the world and lowered global temperatures in an event sometimes known as the “Year Without a Summer” in 1816. The resulting volcanic winter triggered extreme weather and harvest failures around the world.

However, the force of Mount Tambora pales in comparison to the supervolcano that hit what is now Yellowstone National Park before recorded history, 631,000 years ago. That was long before modern humans roamed the Earth. The Yellowstone blast would have been at least ten times that of Mount Tambora, leaving molten ash and rock so thick that it filled entire valleys and left debris over much of the North American continent. The resulting volcanic winter would have killed many animals including some of our prehistoric ancestors (Scientific American, Dec, 2018).

Yellowstone is a simmering supervolcano, characterized by a relatively cool pool of magma sitting on top of a hot plume. The magma is the consistency of crystalline mush that’s “only” 800 C degrees compared with the 1,200 C of the hot plume. The magma is not on boil at this time; however, the relative cool of the magma cap is deceiving. It only takes a few decades of cooking by the mantle below to cause the magma to blow explosively.

When that happens, a few ashes on our cars will be the least of our worries.