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In essence, all lightning can look pretty much the same to the naked human eye. The spark of lightning is a natural phenomenon that occurs in a matter of milliseconds, making it hard to capture the different types of sparks that can occur. Different factors can characterize these different sparks, making key distinctions that can only be discussed when taking an in depth look at the formation of the lightning bolt. These key distinctions include the starting and ending points of the bolt, as well as the direction of the travel of energy, and its appearance from a distance. Feel free to continue reading below as we begin to characterize the 3 general kinds of lightning and the characteristics that make each unique.
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Cloud to Groundwww.media-2.web.britannica.com
Simple as it may seem, cloud to ground lightning is probably the most common type of spark that comes to mind when you think about lightning. Although it is not the most common type of lightning, it is the most "stereotypical" form of lightning that usually occurs during a storm. As a thunder cloud looms over the surface of the earth, negative charges quickly build up along the lower base of the cloud while positive charges also begin to accumulate below on the Earth's surface ("Lightning"). Once these 2 polar opposites are established, it allows an opportunity for a step leader (refer back to 'Thunderstorms' page) to lurch down from the negatively charged cloud base. This is then intercepted by a positive streamer shooting up from the positively charged ground, and causes a huge spark of energy when it meets the step leader. ("Lightning FAQ"). Almost any object and organism can attract a step leader during a storm, but lightning looks to the path of least resistance, so usually taller, more conductive objects are at higher risk of being struck.
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Ground to Cloudwww,news.bbcimg.co.uk
Ground to cloud lightning is, as you could've guessed, a bolt that originates from the ground and travels up to the base of the storm. This type of lightning is the most rare and least naturally-occurring of the three, as it usually requires a tall and highly conductive man-made structure to initiate the positive step leader charge. Once this positive step leader charge shoots up from the point of origin (a skyscraper, antenna, radio tower, etc...), it attracts a negative streamer from the storm cloud and causes the bolt of lightning when these two different particles meet (Robinson).
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Intra-cloudwww.images.fineartamerica.com
About 75% of all lightning produced during a storm never actually leaves the cloud! This form of lightning within a cloud occurs when the bolt finds a region of positively charged particles within the storm, as opposed to on the surface of the earth (Robinson) The result is a lightning bolt that both originates and terminates in the cloud itself, causing the storm cloud to light up!
Lightning can also sometimes leave the cloud but stay in the sky in a phenomenon that can take many forms. All the bolt needs is a region of positively charged particles to react with in order to generate the bolt of lightning. This positively charged region can be in another cloud, causing inter-cloud lightning, or it can simply strike the air around the storm itself if it has enough positive charges built up (Robinson). This sort of lightning that tends to stay in the sky is not a threat to humans on the surface of the earth, but it can often pose threats to aircraft flying in the area. Planes, jets, and helicopters all run the risk of electrical system failure if it is struck by lightning during a storm. |