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Lightning.

What effects on nature is caused by lightning?

Lightning strikes are the number two cause of forest fires. In the American Southwest, about half of forest fires are started by lightning. Lightning causes an average of 20 forest fires a day in the United States. Most of these fires go out on their own. Forest fires caused by lightning are usually 10 times stronger than fires caused by humans. About 100 lightning blots hit the Earth every second. Lightning strikes often hit trees and water. Lightning is hotter than the surface of the sun. This heat causes the air to rapidly shake and vibrate, which is what we hear as thunder. Lightning is one of the most dangerous natural things. We can't really do anything to reduce lightning, but we can always be safe from it.

What causes lightning?

Lightning happens in thunderstorms. It happens when liquid and ice particles above the freezing level collide and build up large electrical fields in the clouds. When electric charges get big enough, a giant "spark" happens between them, like static electricity, making the charge separation smaller. Lighting can happen between clouds, between the cloud and air, or between the cloud and the ground. The cloud-to-ground lightning usually occurs where the darkest clouds are and where the lighter and fuzzier clouds are. Sometimes, a lightning strike can strike outside of the storm miles away and seem like it came out of the clear blue sky. As long as a thunderstorm still has lightning, you know that it still has active updrafts and is still producing precipitation. The temperature of a lightning bolt can be up to 50,000 degrees F, hotter than the surface of the sun. Lightning can often catch trees on fire. Things that are struck by lightning can catch on fire, or show little or no evidence of burning at all.

What are the effects of lightning strikes on humans?

Lightning can be very dangerous. A lightning bolt can have an electric potential of millions of bolts and can be hotter than the surface of the sun. About 2,000 people are injured by lightning strikes around the world each year. In the United States, 9-10% of those people struck die. Lightning is the #2 weather killer in the U.S. The odds of anybody living in the U.S. being struck by lightning in a year is 1:700,000.
Lightning strikes can injure humans in different ways.
-If it is a direct strike, it is usually fatal.
-Contact injury, when the person was touching something that was struck.
-Side splash, when the current jumped from a nearby object to the victim.
-Ground strikes, when the current comes from a strike from the ground to a nearby victim.
-Blast injuries, which causes hearing damage or blunt trauma when being thrown to the ground.
Lightning bolts have been known to heat up the sap of a tree so fast that the tree explodes. When lightning strikes someone it could stop the heart, cause bad burns, damage the nervous system, and stop the breathing. Some people can survive lightning strikes by being given CPR.