Why in the news?

• Volcanoes generate electrical discharges while eruption, known as the Volcanic lightning.

Volcanic Lightning

• What is it?:
  • Volcanic lightning, also known as dirty thunderstorm is a natural electrical discharge that occurs within or near a volcanic ash plume during an eruption.
  • It combines two natural phenomena- volcanic eruptions and lightning, resulting in a spectacular yet dangerous display of atmospheric electricity.
• Mechanism of Formation:
  • Volcanic lightning originates from ash, rock fragments, and ice within an eruption column.
  • The main charging mechanisms include:
    • Triboelectric charging: Friction between ash particles, rock fragments, and ice crystals causes charge separation.
    • Fragmentation charging: Breaking apart magma and rocks during eruption releases charged particles.
    • Induction charging: Rising plume interacts with the Earth’s electric field.
  • Once charge separation reaches a critical point, electrical discharge (lightning) occurs- similar to thunderstorms.
• Scientific Importance:
  • Provides insight into ash plume dynamics and eruption intensity.
  • Helps volcanologists map eruption columns when visibility is low.
  • Lightning detection networks can be used as an early-warning system for eruptions.