Types of Lightning
We’ve all had the experience looking out the window and seeing the flash in the sky and hearing the roar of thunder. What was that flash? It was lightning.
The most common occurrences of lightning are during thunderstorms, although it can be formed during volcanic eruptions and dust storms. It is an electrical discharge which travels approximately 130,000 mph with temperatures up to 30,000 degrees C.
On an interesting note, there is actually a science of lightning: fulminology, which makes a lightning scientist a fulminologist.
Types of Lightning
There are three types of lightning, which takes many forms.
Cloud to Ground Lightning (C-G) is the least common but most understood. It is also the most dangerous in that it causes the most damage. This is the type of lightning that is commonly thought of when the word lightning is mentioned.
There are four kinds of C-G lightning. Bead lightning, also called chained lightning, looks like a string of beads as it breaks up and fades. Ribbon lightning occurs in storms with high winds. It looks like a ribbon because each bolt is blown slightly out of position from the previous one. Staccato lightning is the third kind. This forms many branches and is of short duration, usually appearing in a bright flash. Finally, there is forked lightning, which is just a name used to distinguish lightning with many, many branches.
Ground to Cloud Lightning (G-C) is lightning that starts on the ground and goes up to the cloud, usually a cumulonimbus cloud. This lightning comes in only one form—the strike just zaps up to the cloud.
Next is intra-cloud lightning. This kind is the most common, and occurs within the cloud itself as opposite charged particles move within the cloud. Here, the cloud seems to light up within itself.
The final general type is inter-cloud lightning. This kind occurs between two different clouds when opposite charged particles are near the edges of neighboring clouds.
Special Types of Lightning
Some lightning have a look which does not follow the generalized type. They may not look like what is generally thought of as lightning, or may even be too far away to hear the thunder that accompanies it.
First, there is St. Elmo’s Fire (no, not the movie). This occurs when a positive charge reaches up to the negative charge in the air. Named for the patron saint of sailors, St. Elmo’s Fire glows blue and may occur just before a lightning strike if there is a thunderstorm in the area.
Ball lightning, the least common type of all—if it even exists—occurs as a glowing blue ball less than three feet wide. There is no damage except for minor burn marks as it lasts for just a second or two. It is most commonly seen by airline passengers looking out over the wing.
Heat lightning is seen in storms too far way to hear the thunder. It is named heat lightning because it occurs in the heat of the summer when the skies are not overcast.
The final type actually occurs above the storm. This is called high altitude lightning, and its strikes go up out of the top of the cloud. Among other names, high altitude lightning is also called red sprites or green elves.
Lightning is a very complicated subject, and there is so much more to learn. There is a lot of work to do for those fulminologists out there.