For the first time, scientists have captured high-speed video of a phenomenon in which trees emit an electrical glow by generating sparks during thunderstorms. Results of a study published in Geophysical Research Letters show that tree branches can emit a faint blue light known as a corona discharge, thanks to sensors and cameras dotted in the Blue Ridge Mountains.
The creation of the corona occurs when the storm’s very strong electric field ionizes the air near the sharp edges of tree leaves. Sailors have noticed this same glow on ship masts for hundreds of years. This observation is important for atmospheric scientists, as the results suggest that forested areas may have a much greater influence on the Earth’s electrical balance and greenhouse gas composition than previously thought.
How do trees emit an electric glow without catching fire?
The blue light on treetops is the result of a phenomenon called corona discharge, which is separate from a lightning or wildfire event. The electric field of a thunderstorm is so massive that it can snatch electrons away from air molecules. This causes electricity to be emitted into the air in the form of plasma. Unlike lightning, which is an extremely hot and large discharge, a corona discharge is “cold” electricity. According to Science News, because this type of electricity is less powerful and less diffuse, it accumulates in the sharpest points on the tree, such as pine needles and leaf tips, allowing the trees to emit a faint glow.
However, there will be no actual burning or other type of damage to the tree from this electricity.
Why glowing trees are important for climate
In addition to their beautiful appearance with their sparkling blue glow, the electrical discharge generated by the corona that shoots around tree limbs has a significant impact on air quality.According to research conducted by Pennsylvania State University, electrical discharges resulting from corona discharges on tree limbs produce large amounts of free hydroxyl as well.
Hydroxyl acts as the main cleaning agent for our atmosphere. Hydroxyl radicals are also highly reactive and are used to break down many pollutants and greenhouse gases, such as methane, which would contribute to global warming.
Why do some trees glow brighter than others?
After a thunderstorm, different species are known to respond differently. According to recent studies conducted by scientists and published in the journal Geophysical Research Letters.
This research confirmed that the relative size of a tree canopy is responsible for producing a greater or lesser amount of “ghostly” light with age. Evergreen trees are actively involved in producing this electrical phenomenon. The pointed tips of the needle-like leaf shape of the conifer tree create excellently effective natural “conductors”, allowing the upward-producing electric fields to concentrate greatly at the pointed tips of the vine and create the upward-producing electric flashing blue light more easily (and many times over).
