Sky lights up over Sicily as Mount Etna's Voragine crater erupts
Display of volcanic lightning inside giant smoke and ash cloud over Europe’s tallest active volcano is Voragine crater’s first eruption in two years
The night sky lights up over the east coast of Sicily as Mount Etna’s Voragine crater erupts for the first time in two years. The giant plume of smoke and ash thrown up by the blast creates a dazzling display of volcanic lightning, a mysterious phenomenon seen in many of the most powerful volcanic eruptions.
It is thought that ash particles rubbing together inside the cloud could lead to the buildup of an electric charge that triggers the lightning strikes, much as a weak charge builds up on a balloon rubbed on a jumper.
When the Icelandic volcano Eyjafjallajökull erupted in 2010, the combination of dust with ice and water from an overlying glacier produced a spectacular “dirty thunderstorm” that sent streaks of lightning leaping around inside the plume that drifted overhead.
The tallest active volcano in Europe, Mount Etna stands 3329m high and has been erupting for an estimated 2.5m years. In modern times, towns and villages in the foothills of Etna have been protected by ditches and concrete dams that divert lava flows to safer ground. The volcano has five craters: the Bocca Nuova, the north-east crater, two in the south-east crater complex and the Voragine. The Voragine crater formed inside the volcano’s central crater in 1945.
Volcanic activity in the region is driven by the collision of the African tectonic plate with the Eurasian plate. Magma from molten rock erupts as lava and ash and builds the volcano in the process.
Thanks to: http://www.theguardian.com