What if all the volcanoes on Earth erupted at once?

The simultaneous eruption of more than 1,500 active volcanoes would be absolutely catastrophic

Of the thousands of volcanoes currently active on our planet, there are a handful that could seriously harm life on Earth if they blew. If they all erupted at once we’d be done for. Cone-shaped stratovolcanoes would spew sticky magma upwards in violent bursts, splattering the ground with molten rock. Dome-shaped shield volcanoes would dribble runny lava out across the floor, engulfing anything in its path. Fissure vents would make curtains of fi re and vast lava lakes would open as the ground collapsed. But these would be the least of our problems. Within moments, ash would bury the Earth. Our machines would stop working, buildings would collapse, animals would suffocate, and crops would fail. Sulphurous gases would rise high into the atmosphere, blocking out the Sun’s light and plunging the whole planet into winter. Then, as the gases mixed with water, they’d rain down on the ground as acid. Oceans would become acidic, the shells of sea creatures would dissolve, and food chains would collapse. In the aftermath, carbon dioxide would create a greenhouse effect, heating Earth so fast that life would struggle to adapt. Only time would tell which organisms, if any, would be able to survive.


Extract from WHAT IF…? by Laura Mears. Featured in How It Works 119.

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