what is global warming for kids?

The Planet Earth goes through natural warming and cooling cycles that take tens of thousands of years. Our last cooling cycle covered most of the land with deadly glaciers, crushing the forests and destroying land needed by animals.

Then, ten thousand years ago, the deadly ice age ended and the Earth started warming again. As the glaciers were melted, forests grew and animals had new places to live. We now have cities built in places that were once crushed under a mile of ice.

Thanks to global warming, caused by the Sun's warming rays, we now have lots of places to live and grow food.

The sun is also warming other planets in our solar system. We don't live there, so it doesn't matter to us much. But some day it might.

Compare it to an automobile in the sun shine on a parking lot:

You know how a car in the parking lot gets warmer inside than the air around it? What is happening is that visible light (light we can see) goes through the glass and warms the interior surfaces like the dash and the seat covers. However, when the warmth tries to escape through the glass, it has to leave as infrared light, not as visible light. The glass on the vehicle is like a filter that lets light in, but doesn't let heat out. (The infrared, or heat, is a different wave length, and will not go through the glass as easily as the light wave did.) So the car gets hot, even on a mild day.

Global warming is like an earth-sized case of "hot car."

Some gases in the air like carbon dioxide (what we breath out) act much like the glass in a car. Light comes in, but heat doesn't go back out as easily. These kinds of gases are called "greenhouse gases" because they act like the glass in a greenhouse or a car.

There are other gases that act like green-house gases, but the one many scientists worry about most is carbon dioxide. When we burn gasoline in our cars, coal in our electricity generators, or oil in our heaters, we release more of this carbon dioxide.

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I hope that helps.

You might tell him I think that even if the green-house effect doesn't become "run-away" it is still a good idea to try not to pollute the air.

Hi, that's interesting question! You and your brother might want to check one or several of these nice websites:

* http://epa.gov/climatechange/kids/index.html - the governmental agency's website created to explain the basic phenomena to kids and provide them with some interactive games on this topic

* http://www.pewclimate.org/global-warming-basics/ki... - a list of questions about global warming, compiled by climate scientists for kids, and simple answers to them

* http://11thhouraction.com/takeaction-kids - for the tips from Leonardo DiCaprio on what kids can do to help to combat global warming

Good luck to your brother with his speech and enjoy checking out those websites! Also, you might recommend them to your brother's classmates and friends too!

I think Global Warming occurs when gases are trapped inside the ozone layer. Also, heat is too much nowadays. Global Warming happens because of cutting trees and using things with CFC.

The earth gets warmer sometimes, and sometimes gets cooler. The one thing we know has never happened in the history of the universe is for a planet to remain the same temperature all the time.

Right now, many people think that the temperature of the earth is going to get slightly warmer over the coming years. If that is true, then it is a good thing for people and other living things.