Earth ChangesYellowstone’s supervolcano is creating a 19-mile bulge Posted on March 3, 2026 by Administrator In Yellowstone National Park, a bulge the size of 279 football fields has risen by an inch since last July. With no signs of slowing down, the bump that’s roughly 19 miles across may cause some worry that the iconic locale’s hibernating supervolcano is readying for an apocalyptic reawakening. Although impressed by the situation, the Yellowstone Volcano Observatory’s scientist-in-charge doesn’t sound particularly worried.