1 00:00:00,000 --> 00:00:04,000 To learn more about Earth System Science, and how NASA studies the Earth, 2 00:00:04,000 --> 00:00:09,000 let's go visit with Dr. Melody Ann Avery from NASA Langley Research Center. 3 00:00:09,000 --> 00:00:14,000 Earth System Science is an integration of many scientific disciplines, 4 00:00:14,000 --> 00:00:21,000 including geology, biology, chemistry, physics, oceanography, meteorology, 5 00:00:21,000 --> 00:00:27,000 computer science, and all other sciences that study life and the Earth. 6 00:00:27,000 --> 00:00:33,000 NASA scientists use modern technologies to measure key features of our planet, 7 00:00:33,000 --> 00:00:36,000 such as concentrations of gases in the atmosphere, 8 00:00:36,000 --> 00:00:40,000 and the temperature of the ocean in many locations. 9 00:00:40,000 --> 00:00:44,000 Satellites orbiting our planet provide enormous amounts of data 10 00:00:44,000 --> 00:00:48,000 that scientists use to try to understand how our planet works 11 00:00:48,000 --> 00:00:51,000 and the changes that are happening. 12 00:00:51,000 --> 00:00:55,000 You know, Earth science, long perceived as a minor field 13 00:00:55,000 --> 00:00:58,000 compared to biology and the physical sciences, 14 00:00:58,000 --> 00:01:03,000 is now emerging as an important field because of the new ability of humans 15 00:01:03,000 --> 00:01:06,000 to change the balance of the Earth system. 16 00:01:06,000 --> 00:01:11,000 And students, with Earth System Science, you have greater opportunities 17 00:01:11,000 --> 00:01:15,000 to learn through inquiry, exploration, and discovery, 18 00:01:15,000 --> 00:01:21,000 aided by the expanded use of the Internet and visualization technology. 19 00:01:21,000 --> 00:01:27,000 I think it is fair to say that our quality of life depends on the quality of our Earth scientists 20 00:01:27,000 --> 00:01:32,000 and on the quality of our citizens' knowledge about the Earth system. 21 00:01:32,000 --> 00:01:39,000 This is because understanding the land, air, water, and life of our planet 22 00:01:39,000 --> 00:01:43,000 gives us the knowledge to best manage the world around us. 23 00:01:43,000 --> 00:01:50,000 For the first time in history, we can dramatically change the way the planet works as a whole. 24 00:01:50,000 --> 00:01:53,000 Here are a few questions for you to think about. 25 00:01:53,000 --> 00:01:57,000 How can we change the way the planet works as a whole? 26 00:01:57,000 --> 00:02:02,000 What technologies have humans developed to make that change possible? 27 00:02:02,000 --> 00:02:06,000 Well, there are so many people living on the planet, 28 00:02:06,000 --> 00:02:12,000 and each person needs energy like food, water, heating, and transportation. 29 00:02:12,000 --> 00:02:18,000 All of this energy, if used carelessly, can change the Earth's climate, 30 00:02:18,000 --> 00:02:20,000 deplete its ozone shield, 31 00:02:20,000 --> 00:02:25,000 and dramatically alter the number and kinds of other organisms that share our planet. 32 00:02:25,000 --> 00:02:31,000 Students, let's take a look back at one of the questions that Jennifer posed to you earlier in the show. 33 00:02:31,000 --> 00:02:34,000 What do you think are the parts of the Earth system? 34 00:02:34,000 --> 00:02:40,000 Everything in Earth's system can be placed into one of four major subsystems, 35 00:02:40,000 --> 00:02:45,000 land, air, water, and life. 36 00:02:45,000 --> 00:02:48,000 We call these four subsystems spheres. 37 00:02:48,000 --> 00:02:52,000 Specifically, they are the lithosphere, or land, 38 00:02:52,000 --> 00:02:54,000 atmosphere, or air, 39 00:02:54,000 --> 00:02:56,000 hydrosphere, or water, 40 00:02:56,000 --> 00:02:59,000 and biosphere, or life. 41 00:02:59,000 --> 00:03:02,000 Let's learn a little bit about each sphere. 42 00:03:02,000 --> 00:03:07,000 Suppose you were to slice the Earth in half and view its different layers. 43 00:03:07,000 --> 00:03:09,000 What would it look like? 44 00:03:09,000 --> 00:03:13,000 The lithosphere, sometimes called the geosphere, 45 00:03:13,000 --> 00:03:17,000 contains the hard, solid land of the planet's surface, called the crust, 46 00:03:17,000 --> 00:03:22,000 the semi-solid layer underneath the crust, called the mantle, 47 00:03:22,000 --> 00:03:26,000 the liquid layer near the center of the planet, called the outer core, 48 00:03:26,000 --> 00:03:29,000 and a solid, dense center called the inner core. 49 00:03:29,000 --> 00:03:32,000 The crust is very uneven. 50 00:03:32,000 --> 00:03:36,000 There are high mountain ranges like the Rockies and Andes, shown in red. 51 00:03:36,000 --> 00:03:43,000 Huge plains or flat areas like those in Texas, Iowa, and Brazil, shown in green, 52 00:03:43,000 --> 00:03:47,000 and deep valleys along the ocean floor, shown in blue. 53 00:03:47,000 --> 00:03:51,000 The atmosphere contains all the air in our system. 54 00:03:51,000 --> 00:03:57,000 It extends from the planet's surface to more than 100 kilometers above the planet's surface. 55 00:03:57,000 --> 00:04:01,000 The atmosphere itself is composed of a number of layers. 56 00:04:01,000 --> 00:04:05,000 The middle portion of the atmosphere, the stratosphere, 57 00:04:05,000 --> 00:04:10,000 protects the organisms of the biosphere from the sun's ultraviolet radiation. 58 00:04:10,000 --> 00:04:17,000 When air temperature in the lower part of the atmosphere, the troposphere, changes, weather occurs. 59 00:04:17,000 --> 00:04:22,000 As air in the lower atmosphere is heated or cooled, it moves around the planet. 60 00:04:22,000 --> 00:04:29,000 The result can be as simple as a breeze or as complex as a tornado or hurricane. 61 00:04:29,000 --> 00:04:35,000 The hydrosphere contains all the solid, liquid, and gaseous water of the planet. 62 00:04:35,000 --> 00:04:41,000 The hydrosphere extends from Earth's surface downward several kilometers into the lithosphere, 63 00:04:41,000 --> 00:04:45,000 and upward about 12 kilometers into the atmosphere. 64 00:04:45,000 --> 00:04:51,000 Solid or frozen water can be found in the form of glaciers, ice caps, and icebergs. 65 00:04:51,000 --> 00:04:54,000 This is also called the cryosphere. 66 00:04:54,000 --> 00:05:00,000 Liquid water can be found in the form of oceans, rivers, lakes, streams, 67 00:05:00,000 --> 00:05:03,000 and groundwater beneath the Earth's surface. 68 00:05:03,000 --> 00:05:08,000 Gaseous water, water vapor, can be found in the atmosphere 69 00:05:08,000 --> 00:05:12,000 and also inside your lungs where it is key to life. 70 00:05:12,000 --> 00:05:18,000 The final sphere, the biosphere, contains all the planet's living things. 71 00:05:18,000 --> 00:05:24,000 This sphere includes all of the microorganisms, plants, and animals of Earth. 72 00:05:24,000 --> 00:05:32,000 Within the biosphere, living things form ecological communities based on physical surroundings of an area. 73 00:05:32,000 --> 00:05:36,000 These communities are referred to as biomes. 74 00:05:36,000 --> 00:05:43,000 Deserts, grasslands, and tropical rainforests are three of the many biomes that exist within the biosphere. 75 00:05:43,000 --> 00:05:46,000 Can you determine what biome you live in? 76 00:05:46,000 --> 00:05:51,000 Now it is time for you and your teacher to discuss Jennifer's second question. 77 00:05:51,000 --> 00:05:57,000 How do the parts of the Earth system you identified work together to make Earth function as a whole? 78 00:05:57,000 --> 00:06:02,000 Also, now that you've compared your parts list with NASA's list, 79 00:06:02,000 --> 00:06:06,000 how does each sphere work together to make Earth function as a whole? 80 00:06:06,000 --> 00:06:13,000 This is a great time to pause the program and discuss these questions with your peers or teacher. 81 00:06:13,000 --> 00:06:19,000 Students, remember there is one last question that Jennifer would like for you to discuss with your teacher, 82 00:06:19,000 --> 00:06:25,000 and that is, how is the Earth system itself part of larger systems? 83 00:06:25,000 --> 00:06:30,000 But before you discuss that question, let's send it back to Jennifer.