Global warming - What is it?
Global warming means the earth is getting hotter.
You may have heard of the phrase "greenhouse effect", which describes the way the earth traps the heat from the sun just like a greenhouse.
In a greenhouse, the clear glass (or plastic) walls and roof allow the sun's rays to enter but stop the heat escaping. But the earth is not surrounded by a giant greenhouse, so what stops the heat from escaping?
The answer is, certain gases in our atmosphere, the so called GREENHOUSE gases!
The following animation explains how heat is being trapped in the earth's atmosphere.
A topic that a lot of people are talking about these days, something you've probably heard about on the news, is carbon emissions and "cutting carbon".
World leaders are trying to agree on plans to make sure that humans stop polluting the air with so much carbon dioxide. This is not easy because we all like to make our lives a little bit easier and so use machines to help us. Machines, such as a car, need fuel to work. Unfortunately, the cheapest, most reliable and the most powerful fuels we have today are still fossil fuels. One of the problems with fossil fuels is that when they are burned, to release energy, they also release carbon dioxide along with other pollutants (in smoke) into the air.
If you're wondering why it's important to reduce the amount of carbon dioxide to help stop global warming, it's because carbon dioxide is a greenhouse gas.
Carbon dioxide, along with other greenhouse gases, acts like a blanket that keeps the heat trapped underneath.
Remember, the greenhouse effect is not the "baddie"; without it, it would be too cold for humans to live. We need warmth to survive, but too much warming will destroy the planet as we know it. Pollution can cause too much warming to happen!
One of the most dramatic effects of global warming is rising sea levels. As the planet gets hotter, the ice caps at the North and South pole will melt and as the sea gets warmer it will also expand; this means areas of land could be flooded.
