Lightning
Electrical discharge
| Download this episode | Lightning is an electrical discharge caused by imbalances between storm clouds and the ground, or within the clouds themselves. Most lightning occurs within the clouds. During a storm, colliding particles of rain, ice, or snow inside storm clouds increase the imbalance between storm clouds and the ground, and often negatively charge the lower reaches of storm clouds. Objects on the ground, like steeples, trees, and the Earth itself, become positively charged, creating an imbalance that nature seeks to remedy by passing current between the two charges. Lightning is extremely hot, a flash can heat the air around it to temperatures five times hotter than the sun’s surface. This heat causes surrounding air to rapidly expand and vibrate, which creates the thunder we hear a short time after seeing a lightning flash. Lightning strikes the Earth more than 8 million times per day, with each bolt containing up to one billion volts of electricity. | Lightning is one of the leading causes of weather-related fatalities but the odds of being struck by lightning are only around 1 in 5,00,000 at some time in a person’s life. A total of 20 Americans died last year as a result of being struck by lightning, according to the National Weather Service. Lightning can occur during any time of the year, but lightning casualties are highest during summer. July is generally the month with the most lightning. Lightning strikes often occur in the afternoon. In fact, two-thirds of all lightning casualties occur between noon and 6pm. The Centers for Disease Control and Prevention says that males are five times more likely than females to be struck by lightning. Most lightning strike victims are children and young adults aged 15–34 years who work outside or regularly participate in outdoor recreation. Construction and farming are the two most common occupations for victims of lightning strikes. | The old saying that lightning never strikes twice is merely a myth. Lightning often strikes the same place repeatedly, especially if it’s a tall, pointy object. The Empire State Building is hit an average of 23 times a year. Lightning tends to strike tall or isolated objects, including trees, towers, shelters, flagpoles, bleachers and fences. A person is often the tallest object in an open field. Metal objects and water do not attract lightning but easily transmit electricity once they are hit. Electricity from lightning can travel from outdoor power or telephone lines to electrical equipment or telephone lines inside a house. Lightning delivers a massive electrical pulse over a fraction of a millisecond. Electrical current passing through the body generates heat, which burns and destroys tissues. About 10 percent of people struck by lightning die, most commonly from a heart attack. Other lightning injuries include blunt trauma, neurological syndromes that are usually temporary, muscle injuries, skin lesions and burns. | Providing someone who has been struck by lightning with immediate first aid can mean the difference between life and death. Don’t hesitate to touch a lightning strike victim, people struck by lightning do not carry a charge. First, call 911 and give the emergency personnel information about the victim. It’s safe to use a cell phone during a storm. If necessary, move the victim to a safer location. It is unusual for a victim who survives a strike to have any major broken bones that would cause paralysis or major bleeding complications unless the person suffered a fall or was thrown a long distance. Therefore, it may be safe to move the victim to minimize possible further exposure to lightning. Check to see if the victim is breathing and has a heartbeat. If the victim is not breathing, immediately begin mouth-to-mouth resuscitation. If the victim does not have a pulse, start CPR and continue these resuscitation efforts until help arrives. | If you find yourself caught outside in a lightning storm, you should seek shelter immediately. Avoid tall trees and whatever you do, do not lie on the ground. Lightning causes electric currents along the top of the ground that can be deadly over 100 feet away. Being inside a building doesn’t mean you’re completely safe from lightning. Stay away from windows and doors, and stay off porches and balconies. Stay away from electrical equipment or cords, including corded phones and avoid plumbing, as lighting can travel through pipes. Don’t lie down on or lean against any concrete floors or walls. And just because you don’t see any rain doesn’t mean you’re not at risk from lightning. Lightning often strikes outside areas of heavy rain and can strike as far as 10 miles away from any rainfall. Many lightning deaths occur ahead of storms or after storms seemingly have passed. Remember, if you can hear thunder, you may be in danger of a lightning strike.
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Can occur any time of the year
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Lightning can strike twice
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Get first aid fast
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Seek shelter immediately
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