A presentation to a group of High school children on Global Warming (Ages 13-15)
Hello everyone my name's John and today I'll be talking about global warming. Ok. Before I start I'd like to talk about our planet, Earth. Can anyone guess how old the Earth is? Hands up for thousands of years. Millions? Billions? The Planet Earth is actually 4 and a half billion Years old. We've been on it for about 200,000 Years and if that sounds like a lot it's 0.004% of the time Earth's been around. For us to survive on Earth we need a lot of things but what do we need more then anything, more then computers or boyfriends? Oxygen, because without it we wouldn't be able to breathe. When we breathe, we take in oxygen and breathe out an important gas called Carbon dioxide. Remember this name because you'll be hearing it a lot in science. Carbon dioxide or CO2 is in short what's causing global warming. Now this is where it gets a bit tricky. Our atmosphere is a big blanket of air that does a million different things to keep us alive. Most importantly,when the light from the Sun comes into Earth, it traps them there and so warms us up. So the Sun's rays come down to Earth and get stuck, basically. Without this simple process the average temperature on Earth would be 0 degrees, so be grateful. Right, here's where carbon dioxide comes in. It's one of the gases in the atmosphere that traps the heat and keeps us warm. So the more carbon dioxide we have, the hotter we get. And this is where the problem is. Carbon Dioxide is in nearly all of the things we burn for energy. Can anybody name any? Coal, oil and natural gases are the big ones. And the important thing about them is 2 things. Number one; they're all trapped deep underground and number two they're full of