You might have learnt about volcanos and volcanic eruptions from school, class or from the internet. Then you know that heat and pressure inside the earth explode through the weak spots on the earth and exclude pressure as molten lave and ashes. As time goes on, that molten lava hardens and become hills that we call volcanos. Have you ever heard about volcano lightning? If not, let me explain! Volcanic lightning is an amazing incident of nature. Absolutely it has nothing to do with natural lightning happening in the storms. It is totally connected with everyday physics. Volcanic lightning happens with the eruptions of volcanos.
Some think volcanic lightning starts from the deep ground. But that’s not true. It forms in volcanic ash emitted by volcanos when erupting. Those ashes are cylinder-shaped columns and they are called volcanic plumes. Volcanos that do not have thick volcanic plumes usually do not have this volcanic lightning effect. For example, volcanos in Hawaii eject fountains of lava fluid instead of ejecting thick volcanic plumes. So they rarely show the volcanic lighting when erupting.
How does Volcanic Lightning happen?
You must have definitely experienced lightning that occurs with a thunderstorm. When there is a thunderstorm, there are cold and warm waves of air collide with each other. It causes to have friction between water droplets and particles located in those storm clouds. It induces ionization in air and creates a difference in potential between parts of the clouds. This ends with generating rays within clouds and discharging them as lightning to the ground. The same thing happens when there is a volcanic eruption.
When a volcano is erupting, it releases billions of tiny smoke and ash particles. In the beginning, they are neutral. It means they do not contain an electrical charge. They cause to create friction and this friction changes electrons in the atmosphere into static electricity. It results in a massive lightning bolt! According to some studies done by scientists, when molten lave contact with seawater or groundwater, it creates high positively-charged clouds.
According to some experimental evidence, large particles in the ash plumes become positively charged and small particles become negatively charged. Some powerful volcanos have sufficient heights to create airborne ice crystals. Then both ash charging and ice charging mechanisms happen at different elevations in the same plume at the same time. As a result, it creates upper plume lightning which is similar to thunderstorm lightning.
When did the first volcano lightning discover?
Can you believe that the first volcano lightning was discovered more than 1900 years ago? Yes, that’s true. In the year 79, A Roman historian called Pliny has described the eruption of Mount Vesuvius in his observations. The first scientific study about volcano lightning was also done on Mount Vesuvius by professor Luigi Palmieri during the eruption in 1858. And also he continued his studies during the eruptions in 1861, 1868, and 1872.
The Bulleting of Volcanology published an investigation in 2008 and according to that 27-35% of volcano eruptions have happened with volcano lightning. Many volcano plumes with lightning strikes have been photographed in many parts of the world. Etna in Sicily, Eyjafjallajökull in Iceland, Chaitén in Chile, Mount Augustine in Alaska, Colima in Mexico, Sakurajima in Japan, and Calbuco in Chile are some volcanos that were photographed during volcano lightning.
The brightest single lightning strike that happened was recorded at Sakurajima Volcano in Japan. Volcano lightning is very dangerous when compared to thunderstorms. As they have a high peak current and opposite polarity, they will strike trees and tall structures on the ground. According to scientists, volcanic lightning prevents the extreme stage of a volcanic eruption. As dust particles consist of static electricity and heat, lightning bolts act as a warning about the upcoming lava waves. Lave waves come under gray clouds destroying all the things in their way with an estimated temperature of 16,650 degrees of C!