6. Volcanic Eruptions: Electric Blue in Ash Clouds
Blue lightning finds a distinctive and dramatic backdrop from volcanic eruptions. Volcanoes generate their own weather systems including lightning storms as they release ash and gases into the atmosphere. Sometimes known as a “dirty thunderstorm,” the phenomena of volcanic lightning results from the collision of ash particles creating static electricity. Sometimes this lightning seems blue, producing an amazing contrast against the dark ash cloud. The dry, particle-filled air surrounding the volcano lets the blue wavelengths go farther without dispersing, which makes the colour especially noticeable. Researchers of volcanic lightning have noted that the blue flashes usually start early in the eruption while the plume is still somewhat dry. For volcanologists, this blue lightning is a useful instrument in addition to a stunning visual show. Through tracking the frequency and intensity of blue lightning in volcanic plumes, scientists can learn about the type and direction of eruptions, so enhancing early warning systems for volcanic activity.