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"Street Cents," a teen-centered newsmagazine aired on CBC Television from 1989 to 2006, stood out for its focus on consu | dHNfd2ViMkhKMS0wWlE

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00:00 How are you?
00:01 I'm really excellent.
00:02 That's good.
00:03 And I love my planet, you know.
00:04 Neat planet we live on right there.
00:05 Good, so do I.
00:06 And I've gathered together some materials that are not necessarily environmentally friendly
00:10 and some demonstrations on what the Earth is doing.
00:13 Go ahead.
00:14 It's interesting to me how we're discovering the Earth again.
00:17 You know, in the 1400s we discovered what the Earth looked like.
00:19 That it was round, that there were continents and oceans.
00:21 Now we're discovering how the Earth works and that there are elements of it that can
00:25 change.
00:26 And mainly it's the atmosphere and the oceans and the land, right?
00:29 And people, you hear about things like the greenhouse effect.
00:31 Yeah, that's right.
00:32 Well, that's changing the chemistry of our atmosphere.
00:33 Do you have a demonstration for us?
00:34 And I have a demo here that's been going on for a while.
00:36 There are two thermometers that are exactly the same.
00:39 One thermometer is just sitting outside showing us the air temperature and the other one's
00:42 underneath a glass bowl.
00:44 If you try this in the summertime under the sun, this works very well.
00:47 Just put a thermometer out on the grass.
00:49 If we compare the temperatures of these two thermometers, you'll notice that the one that
00:54 was underneath the glass is several degrees higher than the one that was not.
00:59 And that's because the glass has trapped heat.
01:01 There's a misconception that the sun heats the Earth directly.
01:05 But actually it doesn't.
01:06 The sun doesn't heat the air.
01:08 The sun shines through the air in the same way that light shines through this glass.
01:11 And it heats the ground.
01:12 It's the ground that gets hot and gives off heat.
01:14 So there's a greenhouse around the Earth.
01:16 The greenhouse gas, carbon dioxide, is what acts like the glass here.
01:19 That heat that comes up from the light after being absorbed is kept in there.
01:22 Well, the more carbon dioxide we put into the atmosphere, mainly by burning fossil fuels,
01:26 gasoline, natural gas, things like that, we're thickening the glass.
01:31 And so that can cause the Earth to heat up and cause heat waves and desertification,
01:35 that other nasty thing.
01:36 Now, the ozone layer is very much like sunscreen.
01:39 And I have some sunscreens here.
01:41 When you go out at the beginning of the summer or if you go on a tropical vacation and you
01:44 have pale skin like you, you probably like to put on sunscreen.
01:47 Otherwise, you get burned.
01:48 What burns you is ultraviolet light from the sun.
01:51 That is very deadly radiation.
01:52 Well, the Earth has a natural sunscreen called the ozone layer.
01:55 And ozone is a gas that's in our upper atmosphere.
01:58 And it protects us in the same way that a sunscreen does.
02:01 And right now, it's about a 15.
02:03 Well, you've probably heard that down in the Antarctic, there's a hole in our ozone layer.
02:07 And it's caused by chemicals that we put in there called chlorofluorocarbons.
02:11 So in the Antarctic, we're actually down now to about, oh, say, an 8.
02:16 So we've lost more than half.
02:17 Now, that's a problem because if we lose our sunscreen, then we will start to get sunburned.
02:23 Yes, everybody will not only get more sunburns, but we'll get skin cancer and things like
02:26 that because ultraviolet light, as I say, is dangerous.
02:29 The third thing is the garbage.
02:31 We've got this wonderful stuff called plastic.
02:32 It's a great invention.
02:34 It does all these things.
02:35 You can mold it into all these shapes.
02:36 You can melt it down and use it again.
02:38 But we don't.
02:39 So there's a lot we need to do right now to fix this stuff.

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