The term "supervolcano" implies a volcanic center that has had an eruption of magnitude 8 on the Volcano Explosivity Index (VEI), meaning that at one point in time it erupted more than 1,000 cubic kilometers (240 cubic miles) of material. In the early 2000s, the term “supereruption” began being used as a catchy way to describe VEI 8 eruptions. Explosive events of this size erupt so much magma that a circular-shaped collapse feature, called a caldera, forms above the evacuated magma storage region.  The largest eruption at Yellowstone was 2.1 million years ago and had a volume of 2,450 cubic kilometers. Like many other caldera-forming volcanoes, most of Yellowstone’s many eruptions have been smaller than VEI 8 supereruptions, so it is confusing to categorize Yellowstone as a “supervolcano.”  Other caldera-forming volcanoes that have produced exceedingly large pyroclastic eruptions in the past 2 million ...