supervolcano

Toba, Yellowstone, Tambora, Krakatau, and Pinatubo compared by volume, climate effect, and death toll, with a plain explanation of the VEI scale and why the biggest eruption is rarely the deadliest.

The asteroid that ended the Cretaceous period 66 million years ago released energy equivalent to roughly 100 million megatons of TNT — more than a billion times the bomb dropped on Hiroshima. That is not a metaphor. Scientists have calculated this from the crater geometry, the global debris layer, and the seismic signature preserved in rock. Understanding how energy scales from a hand grenade to a world-altering asteroid impact requires only arithmetic — and it reveals why some explosions leave no survivors within thousands of kilometers.

The Yellowstone supervolcano produces a major eruption roughly every 600,000–800,000 years. The last was 631,000 years ago. If it erupted today, parts of the western United States would be buried in ash, global temperatures would drop, and agriculture would collapse for years.