1 00:00:00,000 --> 00:00:06,000 Today, NASA Connect is at Keesler Air Force Base in Biloxi, Mississippi. 2 00:00:06,000 --> 00:00:07,000 Why? 3 00:00:07,000 --> 00:00:12,000 This is the home of the Hurricane Hunters, the only military unit in the world 4 00:00:12,000 --> 00:00:16,000 to fly directly into a hurricane and collect data on a routine basis. 5 00:00:16,000 --> 00:00:21,000 We'll meet one of these hunters a little later, but first, let's learn more about hurricanes. 6 00:00:21,000 --> 00:00:27,000 A hurricane is a violent tropical storm with damaging winds and torrential rain. 7 00:00:27,000 --> 00:00:31,000 Hurricanes can form in the Atlantic, Pacific, and Indian Oceans. 8 00:00:31,000 --> 00:00:34,000 Hurricanes are given other names in different countries, 9 00:00:34,000 --> 00:00:42,000 such as a typhoon in Southeast Asia, a baguio in the Philippines, and tropical cyclones in Australia. 10 00:00:42,000 --> 00:00:44,000 How does a hurricane form? 11 00:00:44,000 --> 00:00:49,000 A hurricane gets its energy from the warm, moist air at the ocean's surface. 12 00:00:49,000 --> 00:00:54,000 As this air ascends to form clouds, more air is drawn into the hurricane. 13 00:00:54,000 --> 00:00:58,000 Clouds in the ocean spiral inward, and we begin to see the familiar shape of a hurricane. 14 00:00:58,000 --> 00:01:01,000 At the center of a hurricane, the air descends, 15 00:01:01,000 --> 00:01:05,000 forming a very quiet eye with a ring of clouds surrounding it. 16 00:01:05,000 --> 00:01:08,000 The weather in the eye is much different from the weather surrounding it. 17 00:01:08,000 --> 00:01:11,000 The winds grow calm, and the sky may clear. 18 00:01:11,000 --> 00:01:15,000 Surrounding the eye are bands of heavy rains and very high winds. 19 00:01:15,000 --> 00:01:21,000 When a hurricane comes ashore, it brings high waves, severe flooding, and wind damage. 20 00:01:21,000 --> 00:01:26,000 Hurricanes uproot trees, smash buildings, and destroy power lines. 21 00:01:26,000 --> 00:01:32,000 Hurricane Andrew was the third strongest hurricane to strike the United States coastline on record. 22 00:01:32,000 --> 00:01:40,000 Andrew swept through southern Florida and Louisiana in 1992, causing over $25 billion in damage. 23 00:01:40,000 --> 00:01:44,000 Amazingly, few people were killed, despite the widespread destruction. 24 00:01:44,000 --> 00:01:49,000 When we want to know if a hurricane is going to affect us, we turn to meteorologists. 25 00:01:49,000 --> 00:01:54,000 Meteorologists are scientists who study the causes of weather, like hurricanes, 26 00:01:54,000 --> 00:01:57,000 and try to predict where they will go after they've formed. 27 00:01:57,000 --> 00:02:03,000 More accurate forecasts will help prepare people well in advance of an approaching hurricane, 28 00:02:03,000 --> 00:02:05,000 and in turn, help save lives. 29 00:02:05,000 --> 00:02:11,000 For more on how meteorologists predict hurricanes, we came to the Weather Channel here in Atlanta, Georgia. 30 00:02:11,000 --> 00:02:15,000 Well, Jennifer, in order for meteorologists like me to predict hurricanes, 31 00:02:15,000 --> 00:02:22,000 we need to know at least four variables, temperature, moisture, air pressure, and the most important, wind. 32 00:02:22,000 --> 00:02:26,000 Wind directly or indirectly causes all the damage from a hurricane. 33 00:02:26,000 --> 00:02:29,000 For example, winds produce waves, which cause flooding. 34 00:02:29,000 --> 00:02:35,000 Anyway, the winds in and around a hurricane that push it along and produce its motion are called steering winds. 35 00:02:35,000 --> 00:02:39,000 Steering winds control three things, the speed at which a hurricane will move, 36 00:02:39,000 --> 00:02:42,000 where it will move, and whether it will strengthen or weaken. 37 00:02:42,000 --> 00:02:46,000 Well, Dr. Lyons, it seems to me, then, if you know information on the winds, 38 00:02:46,000 --> 00:02:48,000 then you can easily predict what a hurricane will do. 39 00:02:48,000 --> 00:02:53,000 Well, winds are important, but remember, I also have to look at temperature, moisture, and air pressure. 40 00:02:53,000 --> 00:02:55,000 Okay, all right, so where do you get all that information? 41 00:02:55,000 --> 00:02:59,000 We here at the Weather Channel receive data from weather stations on the ground, 42 00:02:59,000 --> 00:03:04,000 from ships and buoys at sea, from aircraft that fly into the hurricane, like the hurricane hunters, 43 00:03:04,000 --> 00:03:06,000 and from satellites in space. 44 00:03:06,000 --> 00:03:08,000 Because our atmosphere is made up of many layers, 45 00:03:09,000 --> 00:03:13,000 ideally data should be collected at all the different heights or altitudes in the atmosphere. 46 00:03:13,000 --> 00:03:19,000 Therefore, we rely mostly on airborne observations and satellites to measure these variables at different altitudes. 47 00:03:19,000 --> 00:03:25,000 So once you receive the data on temperature, moisture, air pressure, and wind, what do you do with it? 48 00:03:25,000 --> 00:03:26,000 I analyze it. 49 00:03:26,000 --> 00:03:31,000 Along with the data we receive, I look at previous data and how it is changing with time. 50 00:03:31,000 --> 00:03:37,000 I use my experience with past hurricanes to predict the hurricane's strength or intensity and its projected path. 51 00:03:37,000 --> 00:03:41,000 Computers at the National Weather Service in Washington, D.C. receive these data 52 00:03:41,000 --> 00:03:45,000 and input the data into numerical models which generate forecasts. 53 00:03:45,000 --> 00:03:48,000 I receive these forecasts at the Weather Channel in Atlanta, Georgia, 54 00:03:48,000 --> 00:03:52,000 along with forecasts made by the National Hurricane Center in Miami, Florida. 55 00:03:52,000 --> 00:03:59,000 My final forecast is a blend of hurricanes' current track and intensity, my forecast, computer forecasts, 56 00:03:59,000 --> 00:04:02,000 and a forecast from the National Hurricane Center. 57 00:04:02,000 --> 00:04:05,000 Finally, I go on television and make a prediction about the path of the hurricane 58 00:04:05,000 --> 00:04:09,000 and how it might affect people on the coast and inland. 59 00:04:09,000 --> 00:04:10,000 Thanks, Dr. Lyons. 60 00:04:10,000 --> 00:04:15,000 Hey, how would you like to use computer simulations to study the behavior of hurricanes 61 00:04:15,000 --> 00:04:18,000 and then predict their path just like Dr. Lyons? 62 00:04:18,000 --> 00:04:20,000 Shelley Canright has the scoop.