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Disaster Strikes by Sam Schultz and Mitchell Nabata |
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Lightning Home Page [ Introduction for Lightning | How Lightning is formed | What is Thunder | Types of lightning | Saftey for Lightning | Facts about Lightning | Conclusion for Lightning ]
Introduction for Lightning:
Lightning is one of the world's most intriguing phenomenons. Lightning can be beautiful to watch, but it can also be a destructive force of nature. The giant static shock, called lightning, happens during thunderstorms and can kill or injury someone if they are struck. There are many precautions that can be taken to cut down your chances of being hit by lightning and steps to take if someone is struck. ![]() ![]() How Lightning is formed:
Lightning is formed in a procedure involving the separation of particles and the attraction of opposite particles. Lightning can go from cloud to ground, ground to cloud or cloud to cloud. Lightning starts with the formation of a thunder cloud. First warm, moist air absorbs enough heat to be lighter than other air. The warm air rises and condenses into large fluffy clouds. The water vapor in the warm air releases stored heat which makes the cloud rise even higher. The cloud needs continuous warm air to rise while it is being formed. When the water vapor and ice crystals become too heavy for the cloud, some upper level precipitation occurs. The new rain creates downdrafts that pull in cooler dry air and create drag on the updrafts. Next, the top of the cloud spreads out and becomes an icy cap. As updrafts and downdrafts work side by side, powerful winds, strong rain, thunder and lightning are created. When the thundercloud is building up, its particles separate. The positive particles go to the top of the cloud, while the negative particles go to the bottom. Super-cooled water drops, formed during the making of the thundercloud, freeze and shatter. The shattering causes the particle separation. Updrafts and downdrafts further separate the particles. The particle separation occurs in the early stages of the thunderstorm development. Lightning usually occurs in the mature stage of a storm. Lightning is an interaction between the cloud and the ground. The large number of negatively charged particles at the bottom of the cloud, attract a large amount of positively charged particles on the ground. The positive and negative particles attract, creating lightning.
What is Thunder:
Thunder is created by the flash of lightning. When the bolt of lightning travels between the cloud and the ground (in cloud to ground lightning), it heats the air to 10 000 °C hotter than the surface of the sun. The heating is so fast that it pushes the air molecules away and creates a shock wave that travels through the air. Eventually, the shock wave turns into a sound wave that is known as thunder.
Types of Lightning:
There are many types of lightning and some occur more often than others. Some types are Ball Lightning, Bead Lightning, Heat Lightning, Ribbon Lightning, Sheet Lightning, and Fork Lightning. Ball Lightning is a very rare phenomenon. Ball Lightning is a floating sphere of light that occurs during thunderstorms. Ball Lightning may move fast or slow and can be loud or even silent. Ball lightning may disappear slowly or very suddenly, and is very unpredictable. No photos have ever been taken of ball lightning and the only evidence that it exists is through eye-witness accounts. Ball lightning is a mystery to the world at this point in time. Bead Lightning looks likes a string of beads and that is why it is called Bead Lightning. Bead Lightning happens when separate illuminated strokes remain along a recently discharged lightning channel for a short period of time, making it look like a string of beads. Heat Lightning is when there are faint flashes of lightning in the distance. Heat lightning got its name because it often happens on hot summer days when thunderstorms are very common. Heat lightning is a sign that a storm is coming. Ribbon Lightning is when it appears that there are two separate return strokes side by side. Ribbon Lightning is made by the wind blowing the return strokes sideways and this creates the illusion of a ribbon of lightning. Sheet Lightning is when lightning inside a cloud makes that cloud “illuminate” and this causes the cloud to look like a sheet of light. Forked Lightning is also known as streak, jagged or zigzagged lightning, and is the visible section of a lightning channel. Almost all lightning is forked lightning and Forked Lightning is the most common type of lightning. ![]() ![]() Safety from Lightning:
There are many things that you should do if you see lightning. Here are some of them:
Facts about Lightning:
Lightning is a giant spark and a strike takes only one millionth of a second. Lightning can heat the air to 10 000 °C. Lightning is hotter than the surface of the sun. Eighty percent of lightning occurs inside a single cloud and the other twenty percent occurs from cloud to ground. If lightning hits the ground it can sometimes fuse the sand or sand and dirt together and turn them into glass called a fulgurate. It is not possible to dodge lightning and that might be why it kills more people than tornados. The Vikings thought that lightning came from the God of Thunder, Thor. Thor had a hammer that he threw at Earth called Mjolnir, and it destroyed everything it hit. The ancient Greeks believed that lightning came from the God Zeus. Zeus threw spears that were lightning bolts. North American Native tribes thought that lightning came from the Thunderbird. The Thunderbird shot lightning out of his eyes, and when his wings flapped it made thunder. ![]() ![]() Conclusion for Lightning:
Some ways that we can help prevent injury or death from lightning would be by making people more aware of the dangers of lightning and how to stay safe. Many people don't worry about getting struck by lightning because it is such a common occurrence. Awareness of the dangers and what to do could save many lives. If you live in a place with many thunderstorms, you could also put a lightning conductor in a field or open space. The lightning would use the conductor instead of other objects because lightning looks for the easiest path to the ground and the tall conductor would be it. You would have to put up warning signs because the field might be dangerous and you may need government consent to put up a conductor. This Diagram 4B shows what could happen if you put up a conductor (right) and what would happen without one (left).
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