Perhaps you have read an article like some of these, suggesting Yellowstone is due to erupt sooner than previously thought (or that an eruption may be larger than previously thought). This is a great illustration of why it is important to check your sources and not trust everything you read. There is no evidence that Yellowstone will erupt in the near future, or in a big eruption. In fact there have been many more small eruptions (i.e., lava flows) at Yellowstone than there have been big eruptions. And just because it erupted in the past doesn't mean the volcano will ever erupt again! Here is a great Snopes article examining this misinformation around our work and others that lead to these inaccurate headlines.
Below is an excerpt of an interview I did with ASU Now discussing our research and separating fact from fiction regarding this beloved and beautiful volcano in America's backyard.
How can we know when a volcano might erupt?
A: Scientists from the Yellowstone Volcano Observatory and academia monitor the volcano constantly to know that it shows no unusual signs of activity or imminent eruption today. We monitor volcanoes by looking at changes in the height of ground surface, changes in the chemistry of the gas being emitted, and earthquakes produced by magma or hydrothermal fluid movement beneath the volcano. It is usual to have earthquake activity and ground deformation at Yellowstone and other active volcanoes every day; most of it is caused by movement of hot fluids that produce the geysers like Old Faithful. But scientists look for unusual activity that suggests the sleeping volcano is awakening. Using these methods scientists are able to identify when there is a higher risk of the eruption in the next several months to year. We don’t see anything like that right now at Yellowstone, nor have we in the recent past.
Also academic scientists like myself and my research group research the conditions in the magma chamber preceding past eruptions by looking at the crystals in the associated volcanic deposits. These are like a black-box recorder of what happened. This allows us to build up an understanding of the events and conditions to look for if the volcano awakens, and how long we might have before an eruption.
Q: What would happen if the Yellowstone supervolcano erupted?
A: Yellowstone has had many more small eruptions than big eruptions. In fact, Yellowstone has had 23 small eruptions that produced a small lava flow since the last large eruption 631,000 years ago. Volcanoes aren’t like earthquakes; they don’t have reoccurrence intervals, so they are not “due to erupt.” So if the volcano were to erupt again, which it might never do, it is more likely to be a small eruption than a large one. The probability of a large eruption again in the future is very, very, very tiny.
Q: What else are you learning about supervolcanoes through your research?
A: Our research uses zones in crystals from the deposits from past eruptions to reconstruct the events preceding past eruptions from lots of different kinds of volcanoes around the world. The zones in these crystals are like the rings in trees; they allow us to reconstruct the climate in the magma chamber during the lifetime of the crystal — the temperature, pressure and chemistry — leading up to past eruptions. The goal is to better understand what causes a volcano to have a big vs. a small eruption and how long we have from signs of unusual activity at the volcano until an eruption. These are relatively new techniques, and we’ve still got a lot of work to do to build up this understanding, but we’re getting there one study at a time.
Some other great resources to learn the facts about Yellowstone and other volcanoes include,