Lightning and Other Wonders of the Sky|
by Q.L. Pearce
In this book, we learn that thunderstorms are formed when warm air rises quickly from Earth into the sky. As the warm air cools, it forms rain clouds called cumulonimbus clouds or thunderclouds. As the warm air continues to rise and cool inside the clouds, it drops water and ice. The water and ice then fall to Earth.
You have probably seen bolts of lightning strike Earth during thunderstorms. Lightning is caused by electricity moving in between clouds or between the clouds and the ground. The electricity is formed when ice and water particles move around rapidly inside the clouds. As the particles move they become oppositely charged and they separate. The positively charged particles go to the top of the cloud and the negatively charged particles sit along the bottom of the cloud. The negative particles along the cloud bottoms grow large and are attracted to the positive charges on the ground. When the attraction between the different charges becomes strong enough, electricity flows from the cloud to the ground. This flow of electricity is a lightning strike.
Lightning lasts only a fraction of a second, but it is filled with energy and is very hot. It can reach temperatures that are much hotter than the sun. The heat of the lightning causes thunder. As the hot electrical charge passes through the air, it heats up the air. The heated air expands quickly and makes the loud noise we call thunder.
Each year rain clouds pour trillions of gallons of water on Earth, giving life to plants and animals across the planet. Sometimes the rain, so necessary to the health of plants and animals, becomes contaminated or even poisonous, and harms or kills the life forms that need it. Acid rain is a recent problem, caused by factories and other modern inventions, such as cars. Smoke stacks from factories and cars release fumes and dangerous gases into the air. The fumes and dangerous gases combine with water and ice particles in the clouds and fall as rain. Acid rain is at least thirty times more acidic than normal rain. It can be very destructive, damaging forests, polluting water, and killing fish and animals.
Try the Lightning and Other Wonders of the Sky Activity to learn more about the processes in the atmosphere.
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