Lists promising “facts you didn’t know” are usually filled with things everyone already knows or things nobody cares about. But volcanoes are weird enough that actual surprising facts exist. Here are some that might actually surprise you, assuming you’re not a volcanologist who’s already insufferably informed about everything.
Volcanic Lightning Happens Because Static Electricity Doesn’t Care About Your Understanding of Physics
When volcanoes erupt explosively, ash particles colliding at high speeds generate static electricity. The result is lightning bolts inside eruption clouds which looks like something from a fantasy movie but is just physics being dramatic.
The 2010 Eyjafjallajökull eruption produced spectacular lightning displays photographed from miles away. The images went viral, which makes sense—volcanic lightning looks fake even when it’s real.
This isn’t rare. Most major explosive eruptions generate some lightning. We just don’t always see it because eruptions often happen at night or in remote locations where nobody’s watching with cameras ready.
The Loudest Sound in Recorded History Was a Volcano That Literally Exploded Itself Into Oblivion
Krakatoa in 1883 produced an eruption heard 3,000 miles away in Perth, Australia and Rodrigues island near Mauritius. The pressure wave circled the globe seven times, registered on barographs worldwide. People in Jakarta 150 kilometers away had eardrums ruptured.
The explosion had equivalent energy of 200 megatons of TNT. Four times more powerfull than Tsar Bomba, the largest nuclear bomb ever tested. One mountain outdid humanity’s most destructive weapon by a factor of four.
Krakatoa essentially disintegrated. The island collapsed into the ocean, triggering tsunamis that killed 36,000 people. What remains is a caldera and Anak Krakatoa—”Child of Krakatoa”—a new volcano growing in the same spot because Earth has a dark sense of humor.
There’s a Volcano That’s Been Erupting Continuously For Over Two Thousand Years Like Some Kind of Geological Energizer Bunny
Stromboli in Italy has erupted every 15-20 minutes for at least 2,000 years. Possibly longer—records only go back so far. It’s so regular that sailors used it as a lighthouse, hence the nickname “Lighthouse of the Mediterranean.”
Small explosions throw glowing lava fragments into the air. Then it rests for 15 minutes. Then repeats. Forever, apparently.
People live on the island despite the volcano’s constant activity. About 500 residents plus tourists who specifically visit to watch eruptions from viewing platforms. The volcano is literally the island’s main attraction and biggest threat simultaneously.
The Biggest Volcanic Eruption in Human History Caused Global Famine and Maybe Inspired Frankenstein
Mount Tambora in Indonesia erupted in 1815 with VEI 7 intensity, ejecting 160 cubic kilometers of material. The eruption killed 71,000 people directly. Then sulfur aerosols in the stratosphere cooled global temperatures, causing crop failures worldwide.
1816 became “the year without a summer.” Snow fell in New England in June. European harvests failed catastrophically. Food prices skyrocketed. Tens of thousands starved.
Mary Shelley spent that gloomy summer indoors at Lake Geneva, writing Frankenstein partly because the weather was too miserable for outdoor activities. So volcanic eruptions influence literature, apparently.
More Volcanic Eruptions Happen Underwater Than on Land and We Miss Almost All of Them
The mid-ocean ridges—65,000 kilometers of underwater volcanic systems—erupt constantly. New ocean floor forms at rates of 2-20 centimeters per year. That’s continuous volcanic activity nobody sees because it happens in darkness miles underwater.
Occasionally underwater volcanoes build high enough to breach the surface, creating new islands. Surtsey off Iceland formed this way in 1963-67. The Tonga eruption in 2022 was submarine, producing the largest explosion since Krakatoa and briefly creating a new island that quickly eroded.
We’ve mapped more of Mars’ surface than Earth’s ocean floor. Countless submarine eruptions occur unobserved, unremarked, until occasionally one makes enough noise to be noticed.
Yellowstone Sits There Being a Supervolcano and Everyone Just Hopes It Stays Sleepy
Yellowstone is a supervolcano with a magma chamber 90 kilometers long. Last major eruption: 640,000 years ago. Average eruption interval: 600,000-800,000 years, which sounds concerningly overdue until you remember geological margins of error span millennia.
If it erupts at full scale, it would blanket much of North America in ash and trigger volcanic winter. We have no meaningful response plan because you can’t evacuate half a continent.
Scientists monitor it continuously. The volcano shows ongoing activity—earthquakes, ground deformation, geothermal features. But “active” doesn’t mean “erupting soon.” Could be tomorrow. Could be 100,000 years. Probably the latter, but the uncertainty is what makes it interesting in a terrifying sort of way.
