1 00:00:00,000 --> 00:00:02,600 We're supposed to meet Dr. Lynn Chambers. 2 00:00:02,600 --> 00:00:04,100 There she is. 3 00:00:04,100 --> 00:00:05,400 Hello, Dr. Chambers. 4 00:00:05,400 --> 00:00:06,700 Treehouse detectives? 5 00:00:06,700 --> 00:00:07,900 I've been expecting you. 6 00:00:07,900 --> 00:00:09,400 Thanks for seeing us. 7 00:00:09,400 --> 00:00:11,400 Well, we wanted to learn more about clouds 8 00:00:11,400 --> 00:00:12,600 and what they mean. 9 00:00:12,600 --> 00:00:14,700 Do you know how a cloud is formed? 10 00:00:14,700 --> 00:00:15,900 Not really. 11 00:00:15,900 --> 00:00:19,000 I always thought it's when the sun sucks up a lot of water. 12 00:00:19,000 --> 00:00:20,200 Then the clouds are formed. 13 00:00:20,200 --> 00:00:21,200 Good guess. 14 00:00:21,200 --> 00:00:23,100 But maybe I can explain it to you a little better 15 00:00:23,100 --> 00:00:24,600 if I make a cloud for you. 16 00:00:24,600 --> 00:00:26,600 You can make a cloud? 17 00:00:26,600 --> 00:00:28,100 Do we get to go up in an airplane? 18 00:00:28,100 --> 00:00:29,100 No. 19 00:00:29,200 --> 00:00:30,800 We can do it right here. 20 00:00:30,800 --> 00:00:33,200 First, we'll fill this jar with water. 21 00:00:33,200 --> 00:00:35,700 We need about two centimeters of water. 22 00:00:35,700 --> 00:00:37,700 Did you know that 2.5 centimeters 23 00:00:37,700 --> 00:00:39,300 is equal to one inch? 24 00:00:39,300 --> 00:00:41,900 Then we place some ice cubes in this metal tray 25 00:00:41,900 --> 00:00:44,000 and place it on top of the jar. 26 00:00:44,000 --> 00:00:46,100 The air inside the jar will cool 27 00:00:46,100 --> 00:00:48,500 and the water vapor in the air will condense. 28 00:00:48,500 --> 00:00:50,100 What does condensed mean? 29 00:00:50,100 --> 00:00:52,500 Have you ever been outside on a really cold day? 30 00:00:52,500 --> 00:00:54,000 What happens when you breathe? 31 00:00:54,000 --> 00:00:55,600 My breath looks like smoke. 32 00:00:55,600 --> 00:00:57,000 That's condensation. 33 00:00:57,000 --> 00:01:00,000 Your breath contains water vapor just like the air does. 34 00:01:00,000 --> 00:01:01,300 Oh, that reminds me. 35 00:01:01,300 --> 00:01:02,600 We forgot to add particles. 36 00:01:02,600 --> 00:01:04,000 Do you see a cloud yet? 37 00:01:04,000 --> 00:01:05,900 I see water drops forming. 38 00:01:05,900 --> 00:01:08,900 The water condensation on the jar is not a cloud. 39 00:01:08,900 --> 00:01:11,700 We need to add something for the water to condense on. 40 00:01:11,700 --> 00:01:12,900 Any ideas? 41 00:01:12,900 --> 00:01:15,900 Um, how about some dust from my room? 42 00:01:15,900 --> 00:01:18,500 Or how about chalk dust? 43 00:01:18,500 --> 00:01:19,500 That might work. 44 00:01:19,500 --> 00:01:20,900 We could use a number of things. 45 00:01:20,900 --> 00:01:24,500 In the real world, it would be sea salt, dust, 46 00:01:24,500 --> 00:01:27,200 volcanic aerosols, or man-made pollution. 47 00:01:27,200 --> 00:01:29,200 Since we don't have any of those here, 48 00:01:29,200 --> 00:01:30,500 I'm going to use a match. 49 00:01:30,500 --> 00:01:32,400 This is the part where you need an adult. 50 00:01:32,400 --> 00:01:34,100 So what will happen? 51 00:01:34,100 --> 00:01:35,100 Let's give it a try. 52 00:01:45,900 --> 00:01:48,600 I can see a cloud forming. 53 00:01:48,600 --> 00:01:50,800 How do we know that's just not the smoke from the match? 54 00:01:50,800 --> 00:01:53,200 We can shut off the condensation and make the cloud 55 00:01:53,200 --> 00:01:55,500 disappear by simply taking the ice away. 56 00:01:55,500 --> 00:01:56,700 Do you want to try it? 57 00:01:56,700 --> 00:01:57,200 Sure. 58 00:02:01,500 --> 00:02:03,000 It vanished. 59 00:02:03,000 --> 00:02:05,000 The cloud we made looked very wispy. 60 00:02:05,000 --> 00:02:07,500 But in the sky, we see all different kinds of clouds. 61 00:02:07,500 --> 00:02:08,800 Are there different types? 62 00:02:08,800 --> 00:02:11,100 Yes, there are three main cloud types, 63 00:02:11,100 --> 00:02:13,500 cirrus, cumulus, and stratus. 64 00:02:13,500 --> 00:02:17,500 Cirrus clouds are high clouds that form above 6,000 meters. 65 00:02:17,500 --> 00:02:19,100 What are those round puffy clouds 66 00:02:19,100 --> 00:02:20,900 that look like cotton candy? 67 00:02:20,900 --> 00:02:22,400 Those are cumulus clouds. 68 00:02:22,400 --> 00:02:23,700 They're found at different heights. 69 00:02:23,700 --> 00:02:26,200 They're often seen on dry, sunny days. 70 00:02:26,200 --> 00:02:28,400 What do you call those little clouds that cover the sky? 71 00:02:28,400 --> 00:02:29,800 Those are stratus clouds. 72 00:02:29,800 --> 00:02:33,100 Their base is usually found at low levels below 500 meters. 73 00:02:33,100 --> 00:02:35,600 And they form a layer or sheet across the sky. 74 00:02:35,600 --> 00:02:37,200 Do different types of clouds indicate 75 00:02:37,200 --> 00:02:38,500 different types of weather? 76 00:02:38,500 --> 00:02:40,800 Some clouds do indicate different types of weather. 77 00:02:40,800 --> 00:02:42,500 One of our treehouse detectives' class 78 00:02:42,500 --> 00:02:44,100 belongs to your cloud club? 79 00:02:44,100 --> 00:02:46,100 Yeah, it's called school for students' 80 00:02:46,100 --> 00:02:47,800 cloud observations online. 81 00:02:47,800 --> 00:02:50,000 We have 1,000 schools around the world 82 00:02:50,000 --> 00:02:52,200 where students are observing clouds. 83 00:02:52,200 --> 00:02:54,400 They send their data to a NASA computer 84 00:02:54,400 --> 00:02:56,300 and their observations are compared to those 85 00:02:56,300 --> 00:02:59,000 from CIRRUS instruments flown on satellites. 86 00:02:59,000 --> 00:03:01,800 So kids actually help NASA? 87 00:03:01,800 --> 00:03:05,100 Yes, we use the students' data to help us identify clouds 88 00:03:05,100 --> 00:03:07,300 with which the satellite has trouble seeing. 89 00:03:07,300 --> 00:03:09,000 That is way too cool. 90 00:03:09,000 --> 00:03:11,900 Just think, kids are actually helping NASA. 91 00:03:11,900 --> 00:03:13,300 Thanks, Dr. Chambers.