With molten lava flowing down and flames flickering amid clouds of dust, the sight of a volcanic eruption is both terrifying and awe-inspiring. So, what would happen if all the volcanoes on Earth erupted simultaneously?
Scientists estimate that there are about 1,500 active volcanoes on Earth, not including the uncounted number of underwater volcanoes. Each day, between 10 to 20 volcanoes erupt around the globe. However, scientists believe that the likelihood of all these volcanoes erupting at once is extremely low, to the point of being nearly impossible.
But suppose this does happen, would Earth have any chance of survival? Parv Sethi, a geologist at Radford University in Virginia, states that the answer is no.
The eruption of just the surface volcanoes would be enough to trigger severe environmental impacts in a domino effect, with power many times greater than that of nuclear bombs. While the molten lava would initially kill those living near the volcanoes, this number pales in comparison to the casualties caused by climate change.
Volcanic Eruption. (Image: livescience.com)
Sethi predicts that if all the volcanoes on Earth were to erupt simultaneously, a thick blanket of ash would cover the Earth, blocking out all sunlight.
“The Earth would be completely plunged into darkness. Without light, trees would be unable to photosynthesize and grow, crops would fail, and temperatures would drop significantly,” the scientist explained. This blanket of ash could envelop the Earth for up to 10 years.
In reality, not all volcanoes are capable of producing large amounts of ash; for instance, the volcanoes in Hawaii primarily emit lava. However, the list of 1,500 active volcanoes compiled by the United States Geological Survey includes supervolcanoes, which could blanket the entire United States in a layer of ash with just one eruption.
Even if one were to survive the ash cloud, another problem arises: acid rain. The emissions from erupting volcanoes contain significant amounts of hydrochloric acid, hydrogen fluoride, hydrogen sulfide, and sulfur dioxide, which, in large concentrations in the atmosphere, can lead to acid rain, contaminating groundwater and ocean surfaces.
Acidic ocean water would lead to mass die-offs of coral and marine life, disrupting the marine food chain and potentially causing mass extinction events, similar to those that occurred in Earth’s past at the end of the Permian, Triassic, and Cretaceous periods.
Furthermore, the ash and gases released into the atmosphere would block sunlight, causing Earth’s temperatures to drop significantly, even if only temporarily.
Although volcanic eruptions also release carbon dioxide, which can contribute to global warming, scientist Sethi argues that the amount of carbon dioxide emitted from 1,500 simultaneous volcanic eruptions would be so great that it would poison the atmosphere and raise Earth’s temperatures too high, creating an environment unsuitable for human life.
In the face of this apocalyptic scenario of simultaneous volcanic eruptions, Sethi believes that only extremophiles—bacteria that thrive in extreme conditions—would be able to survive. These organisms live in incredibly harsh environments like hot springs or deep-sea vents, where they are safe from the destruction on the surface.
Another science fiction scenario considers that only a few people might survive by taking refuge in underground bunkers built by governments and the wealthy, waiting for the disaster to pass, or abandoning Earth to venture into space.
“In that case, the luckiest ones would actually be those who have died,” Sethi concludes.
