What It's All About
Climate change, also known as global warming, means the whole world is warming up. The planet regularly goes through periods of warmth and cold, but this time things are heating up too fast. Scientists who have been studying it for a long time have determined that it's not a natural warming like in the past. People are making the world warmer, but how and what does it mean?
We Live in a Big Greenhouse
If you've ever been to a greenhouse, maybe you remember how warm it was inside. That's because the seedlings and plants need a stable, warm environment to grow. The greenhouse keeps the plants protected from the weather and makes sure the temperature doesn't get too cold. The Earth lives in a greenhouse, too, but you can't see it. It's called the atmosphere, and it protects the Earth from the cold, harsh environment in outer space while still letting in heat from the sun to keep us warm and letting out any extra heat we don't need.
Hippo Works (www.hippoworks.com) makes funny, short cartoons about a variety of environmental issues, including a series on global warming. Episode 4 is about methane gas and has an especially catchy tune called “The Power of Poop.” It injects laughter into a very serious subject.
The atmosphere is made up of gases. Extra gases are created from things like exhaust from cars and pollution from smokestacks. These extra gases are making the greenhouse stronger; while that may sound good, it's not. A stronger greenhouse means the extra heat from the sun gets trapped in our greenhouse.
You can see how this works by taking two jars and putting a teaspoon of water into each. Put a lid on just one jar, and place them both in a sunny spot. Wait a few hours and see what happens. The open jar won't change, but the closed jar will be steamy inside. Why? Just like the greenhouse effect in our atmosphere, heat from the sun could not get out of the closed jar.
The United States, European countries, Japan, and China emit the largest amounts of greenhouse gases. It's unfair, but the places releasing the least amounts, like Africa and South America, are where people are suffering the most from the impacts of climate change. Droughts are making lakes and rivers dry up, and it's becoming difficult to grow crops for food.
What a Difference a Couple of Degrees Makes
You might be wondering what the big deal is. Why does it matter if the Earth gets a little warmer? Well, each thing in nature depends on each other. When the Earth heats up, the natural balance is upset and things can go wrong. For example, global warming is slowly melting the ice at the poles. What happens when ice melts? It turns into water and makes the ocean levels rise all over the world. People who live near the ocean will have to move inland as the water creeps up. You can see how this happens by placing a bowl upside down in the middle of a cake pan. Pour in some water to create an “island.” Place a small glob of clay near the water's edge; it can represent a house or a city. Now slowly pour in more water to simulate the melting polar ice caps and watch as the water level goes up and the clay ends up in the water. Dropping ice cubes into the bowl and waiting for them to melt takes longer, but it illustrates the point even more clearly.
Scientists also believe global warming is making the weather change. There are more heat waves. There are more severe storms and droughts. There is more lightning, which can spark forest fires. None of this is good for people or the plants and animals of the Earth.
