Were you aware that there are many types of lightning? There are Anvil crawler (Spider), Ball, Bead, clear-air, Cloud-to-air, Cloud to Ground, Cloud to Cloud, Dry, forked, heat, Upward lightning or ground-to-cloud lightning, Staccato lightning, and Super Bolts, to name a few.
There are three primary types of lightning, defined by what is at the “ends” of a flash channel.
- Intracloud (IC), which occurs within a single thundercloud unit
- Cloud to cloud (CC) or intercloud, which starts and ends between two different “functional” thundercloud units
- Cloud to ground (CG), that primarily originates in the thundercloud and terminates on an Earth surface, but may also occur in the reverse direction, that is ground to cloud.
The air between the clouds and Earth blocks the connection — until the charge gets so strong that an electrical impulse called a “stepped leader” shoots down from the cloud.
The leader drops in steps of about 150 feet each at about 136,000 mph, until it almost reaches the ground. That’s when an electrical charge called a streamer rises up to meet it and complete the circuit.
A lightning bolt is about 54,000 degrees Fahrenheit — roughly five times hotter than the surface of the sun!
One can approximate the distance to the strike by timing the interval between the visible lightning and the audible thunder it generates. A lightning flash preceding its thunder by one second would be approximately 1000 feet in distance; a delay of three seconds would indicate a distance of about 3000 feet, and a flash preceding thunder by a five second count would indicate a distance of approximately one mile, thus, a lightning strike observed at a very close distance will be accompanied by a sudden clap of thunder, with almost no perceptible time lapse.
Objects struck by lightning experience heat and magnetic forces of great magnitude. The heat created by lightning currents traveling through a tree may vaporize its sap, causing a steam explosion that bursts the trunk. As lightning travels through sandy soil, the soil surrounding the plasma channel melt, forming tubular structures called fulgurites. Even though roughly 90 percent of people struck by lightning survive, humans or animals struck by lightning may suffer severe injury due to internal organ and nervous system damage, keeping in mind that lightning kills about 2,000 people a year, so stay inside during lightning storms.
Buildings or tall structures hit by lightning may be damaged as the lightning seeks unintended paths to ground. By safely conducting a lightning strike to ground, a lightning protection system can greatly reduce the probability of severe property damage. Lightning also serves an important role in the nitrogen cycle oxidizing diatomic nitrogen in the air into nitrates which are deposited by rain and can fertilize the growth of plants and other organisms. The very high temperatures generated by lightning lead to significant local increases in ozone and oxides of Nitrogen. The ground has a positive charge, so the positively charged ground attracts the negative lightning bolt, and when the two meets, it produces a strong electrical current. This reaction helps our earth maintain its electrical balance as lightning helps transfer negative charges back to the earth.
Because the electrostatic discharge of terrestrial lightning superheats the air to plasma temperatures along the length of the discharge channel in a short duration. Kinetic theory dictates gaseous molecules undergo a rapid increase in pressure and thus expand outward from the lightning creating a shock wave audible as thunder. Since the sound waves propagate not from a single point source but along the length of the lightning’s path, the sound origin’s varying distances from the observer can generate a rolling or rumbling effect.
Lightning at a sufficient distance may be seen and not heard; there is data that a lightning storm can be seen at over 100 miles whereas the thunder travels about 20 miles. Anecdotally, there are many examples of people saying ‘the storm was directly overhead or all-around and yet there was no thunder’.