Charges at Work
By: Brandon Chong
Lightning
Lightning is a massive electric discharge that is caused by unbalanced electric charges up in the atmosphere, which therefore, results in a strike. These strikes are from the cloud to itself, or cloud to the ground and it is often accompanied by the loud noise of thunder.
A Cloud to ground lightning usually strikes for over 5 kilometers long, while a typical thunderstorm can have up to 3 or more strikes per minute at its peak.
Lightning is usually produced in the cumulonimbus clouds which are up to 25 kilometers high and 5 - 6 kilometers above the ground.
Interestingly, lightning may also occur during snow storms, volcanic eruptions, dust storms, forest fires or tornadoes.
How Lightning is Created
2. The negative charges that are located on the bottom of the cloud induces a positive charge on the ground which is below the cloud. This is accomplished by repelling the negative charges in the ground.
Some Types of Lightning
Anvil Crawlers
These anvil crawlers form tree- like lightning discharges and they are sometimes referred as ‘crawlers’ or rocket lightning’. Compared to most other lightning discharges, an anvil crawler’s movements are slow enough that a human or a normal speed video can see its motion across the sky. They often span large distances and thus filling the sky with spectacular lightning discharges.
Cloud-to-Ground Lightning
Cloud to Ground Lightning is one of the best known and it is the second most common type of lightning. This type of lightning is generally a lightning discharge between a cumulonimbus cloud and the ground. It is caused by a leader stroke moving down from the cloud. This form of lightning has proved to be life threatening and also a threat to property, in the view of the fact that it strikes the ground.
Cloud to Cloud Lightning
However, Lightning discharges does not always have to contact the ground. They could also occur between areas of clouds called cloud to cloud lightning. They are the most common found between the upper anvil portion and lower reaches in a given thunderstorm. Cloud to cloud lightning could also sometimes be observed at great distances during the night as “heat lightning.” In these situations, the observer of the lightning may only see the flash of light, but without the accompaniment of the sound of thunder.
References
- Zavisa, John. "How Lightning Works." HowStuffWorks. Howstuffworks, n.d. Web. 12 Feb. 2013.
http://science.howstuffworks.com/nature/natural-disasters/lightning1.htm
- "Lightning." Lightning. The Physics Classroom, n.d. Web. 12 Feb. 2013.
http://www.physicsclassroom.com/class/estatics/u8l4e.cfm
http://www.theairlinepilots.com/met/cloudtocloudlightning.htm
http://stormhighway.com/types.shtml
Blake, Lessa, Michael Mazza, Alex Mills, Frank Mustoe, Jim Ross, and Thomas Stiff.ON Science 9. Toronto: Diane Wyman, 2009. Print.
http://www.theairlinepilots.com/met/cloudtogroundlightning.htm
http://www.ec.gc.ca/foudre-lightning/default.asp?lang=En&n=9353715C-1