Researchers from Arizona State University analyzed minerals in fossilized ash from the volcano’s most recent mega-eruption (more than 630,000 years ago) and found some startling details, according to National Geographic.
The minerals showed that changes in temperature and composition had built up in only a few decades. Until now, scientists believed it would take centuries for the supervolcano to make this transition.
“We expected that there might be processes happening over thousands of years preceding the eruption,” study co-author Christy Till said in an interview with the Times.
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If it does blow, the volcano has the ability to expel 1,000 cubic kilometres of ash and rock, which could blanket the United States and possibly send the world into a volcanic winter (volcanic ash and sulphur cutting out sunlight and cooling the Earth’s surface).
The explosion could also be 2,000 times the size of 1980’s eruption of Mount St. Helens, which killed 57 people.
“It’s shocking how little time is required to take a volcanic system from being quiet and sitting there to the edge of an eruption,” study co-author Hannah Shamloo said in the Times article.
The researchers added it’s still too early to determine an exact timeline of when the supervolcano will erupt.
The new discovery, which was presented in August, comes after another study in 2011, in which researchers found the ground above the magma chamber bulged by up to 25 centimetres in a span of about seven years.
The past predictions have worried NASA so much that the organization is now working on a way to prevent the supervolcano from destroying humankind. According to National Geographic, NASA plans to drill into the magma chamber to cool down the volcano.
However, the U.S. Geological Survey (USGS) considers the risk of an apocalyptic eruption at Yellowstone in the next few thousand years “exceedingly low.”
“If another large caldera-forming eruption were to occur at Yellowstone, its effects would be worldwide. Thick ash deposits would bury vast areas of the United States, and injection of huge volumes of volcanic gases into the atmosphere could drastically affect global climate,” the USGS states.
“Fortunately, the Yellowstone volcanic system shows no signs that it is headed toward such an eruption in the near future.”
What is a supervolcano?
Supervolcanoes usually have a few common characteristics, including a massive cauldron-like crater, also known as a caldera, and a vast magma source, according to the USGS.
They usually have highly infrequent and intense explosive blasts that measure magnitude eight on the Volcano Explosivity Index (erupting more than 1,000 cubic kilometres).
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Yellowstone has had three major volcanic events in the past 2.1 million years, which led to the creation of the calderas in the national park. You can still see evidence of the volcano’s active state, with natural wonders like the Old Faithful geyser.
Other supervolcanoes in the world include:
- Lake Toba, Indonesia
- Taupo, New Zealand
- Long Valley Caldera, California
- Valles Caldera, New Mexico
- Aira caldera, Japan
- Campi Flegrei, Italy