transitionThe phenomenon that I choose to talk about is the ‘Volcanic Lightning’. But, before I start talking about this, I’m going to touch a little about static electricity.
Have you ever wonder about why does your hair stick to a balloon after rubbing the said balloon on your hair? Well the answer to your question is static electricity. Static Electricity is a familiar electricity phenomenon which particles are transferred from one body to another. Therefore, when you rub a balloon against your hair, the balloon will steal electrons from the hair leaving it completely positively charged. Since opposite attracts, when you try to retract the negatively charged balloon from your hair, the positively charged hairs causes it to be attracted to the balloon.
transitionThe phenomenon of volcanic lightning also revolves around this theory.
A volcanic lightning is basically a rare weather phenomenon which is usually related to the production of lightning in a volcanic plume. It is by far the most vivid demonstration of power, beauty and mystery that the Mother Nature has to offer.
This breath-taking phenomenon has happened several times in our decade. Some of the notable eruptions are from the Chaitén, Kirishima and Sakurajima volcanoes. These dirty storms are twice as powerful as a normal supercell thunderstorm.
Before science and technology have developed to where it is now, the ominous lightning flashing above the erupting volcanoes are always considered as a nightmare as it is considered almost impossible to happen. However, with the advancement that we have achieved now, scientists are a step closer to understanding the phenomenon of volcanic lightning also known as the ‘dirty thunderstorm’.
However, the task of unravelling the origin of volcanic lighting has been proven to be tough.
In normal thunderstorms, the cause of lightning is the colliding small bits of ice crystals which is frozen raindrops. This collision generates enough electric charge in a cloud to trigger lightning. However, ash clouds are harder to observe than supercell because it is less predictable.
Volcanic lightning has little to nothing to do with tectonic activity, and everything to do with everyday physics. Unlike lava, volcanic lightning was not formed deep in the volcano. It only started to form in the volcanic plume, which is simply the ash cloud that caused by eruptions. Volcanoes like the ones in Hawaiian are more likely to eject lava fountains than thick plumes of ashes. Therefore, these types of volcanoes would never have volcanic lightning.
When the tiny particles that make up a volcanic plume are in a volcano, it is tightly packed and are under high pressure. The atmosphere above ground are way less dense than the atmosphere beneath a volcano. This change in density contributes greatly to the occasion of volcanic lightning. As the previously dense particles are ejected with a very high acceleration into the lose atmosphere, they rubbed violently against each other. This generates friction, which causes ash particles gain or lose electrons and become electrically charged. Due to a big difference in the mass between electrons and protons, the plume experiences charge separation as the charged particles were released into the less dense atmosphere in an impressive acceleration.
The distance between the positively charged particles and the negatively charged particles continues to increase until it becomes too big for air to resist the flow of electricity. Since opposite attracts, there is a strong attractive force between the charged particles. This creates a path for the lightning to tear through the volcanic plume to connect the separated positively and negatively charged particles.