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Bolts
Bolts

Cloud-to-ground lightning bolts are the most familiar and the most dangerous. Most cloud-to-ground lightning strikes come from the negatively charged bottom of the cloud to the positively charged ground below. Often, cloud-to-ground lightning bolts strike the highest object, like the top of a building or the highest limb on a tree. The lightning strikes can cause fire and property damage. If a human being is the highest object in the lightning bolt's path, the strike can cause severe injury or death. Although cloud-to-ground lightning is the most dangerous, it is also the most understood because it leaves so much evidence behind.

Most cloud-to-ground lightning strikes bring negative energy down to the ground, but some strikes deliver positive charge to the ground. Positive strikes are less common and emerge from the higher regions of the thundercloud. Some meteorologists believe that positive lightning strikes indicate storms that are more likely to spin out tornadoes.

Not all lightning bolts strike the ground. Many lightning discharges occur within and between thunderclouds. The most common type of lightning, called intracloud lightning, strikes between positive and negative areas in the same cloud. The bolt is not usually visible, but rather appears like a broad flash in the sky. A less common lightning strike occurs between oppositely charged areas of separate clouds. Known as intercloud lightning, the strike passes through clear air and provides a stunning bolt of light. Intercloud lightning poses a particular hazard to airplanes in flight because it passes through the clear air between clouds.

 
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