What causes lightning?
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Lightning is a natural electrical discharge that occurs during thunderstorms. It is caused by the buildup and release of electrical energy between the cloud and the ground. The specific process leading to lightning formation is not fully understood, but it is believed to involve the following steps:
1. Charge separation: Thunderstorms contain a combination of positively charged ice particles and negatively charged water droplets. Updrafts within the storm help to separate these charges, with the top of the cloud becoming positively charged and the lower part becoming negatively charged.
2. Electric field formation: The charge separation produces an intense electric field within the storm cloud. This electric field increases as the charge separation becomes more significant.
3. Leader formation: When the electric field becomes strong enough, a channel of charged particles called a "stepped leader" starts to form. It descends from the negatively charged portion of the cloud toward the ground. This channel is not visible to the naked eye.
4. Streamer formation: As the stepped leader approaches the ground, it induces a positive charge on the objects or structures on the ground. These positively charged objects then send up a streamer, which is a branch-like channel of positive charge.
5. Connection and discharge: Once the stepped leader and streamer meet, a completed path is formed for the electric current to flow. This path allows the discharge of accumulated electrical energy in the form of a bright flash of light, known as lightning. The lightning bolt can contain multiple strokes that occur within a fraction of a second.
It is important to note that this explanation is a simplified version of the complex phenomena occurring in a thunderstorm. The study of lightning is an ongoing scientific pursuit, and research is continually uncovering new insights into the exact mechanisms behind its formation.