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Abstract
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Smoke filled the cabin as the Boeing 747 plunged towards snow-covered mountains in southern Alaska. All four engines had shut down, and it took the pilots eight long minutes to regain control of the aircraft. No one on board was hurt — but they had a very close call with an erupting volcano. The jet had flown through an ash cloud.
Incidents such as this near miss from 1989 show why geologists have long sought to forecast volcanic eruptions: to protect people on the ground and in the air. Now scientists are one step closer to this goal.
Maurizio Ripepe, a geophysicist at the University of Florence and his colleagues have created the world’s first automated volcano early-warning system, which alerts authorities near Mount Etna in Sicily about one hour before an eruption. The team described the system last month1 in the Journal of Geophysical Research: Solid Earth.
The approach relies on the fact that volcanoes are noisy. Their rumblings and explosions can sound like a jet engine or even a high-pitched whistle, but they also produce low-frequency infrasound waves that people cannot hear. Unlike seismic waves, infrasound waves can travel for thousands of miles, allowing scientists to spot volcanic eruptions from afar. When Krakatoa erupted in Indonesia in 1883, its infrasound signal travelled around the globe twice.
Bubble and squeak
With that in mind, Ripepe and his colleagues turned to Mount Etna, Europe’s largest active volcano. At first, they wanted to create a simple system that could detect an eruption using data from an existing array of infrasound sensors, and automatically alert authorities. But their ambitions grew when they discovered that the volcano often produces infrasound waves before it erupts, making prediction possible ...
Language: en |