Weather

1. Weather By: Drew Harris

2. Atmosphere What is atmosphere? Atmosphere is the air that surrounds Earth. It was formed millions of years ago by volcanoes. Carbon dioxide absorbs heat and helps to heat the planet. This helps to heat the planet. Water vapor, or the gas state of water, also does this. That is how humid areas like Buena Vista are very hot. Humidity is the amount of water vapor in air.

3. Air pressure Every day air particles press down on the surface. This is called air pressure. The air particles near the surface are closer together and tighter than most. They loosen the higher they go. Therefore, the air pressure is less the higher you go.

4. The Troposphere The atmosphere has four layers. They are the troposphere, stratosphere, mesosphere, and thermosphere. The troposphere is the closet layer to the surface. We breathe its air everyday. It has most bad weather in it. In this layer air temperature decreases with height.

5. The Stratosphere The second layer from earth is the stratosphere. Some airplanes that fly long distances fly here to be above most bad weather. This area contains most of the atmosphere’s ozone and protects us from the sun’s harmful rays. Temperatures in the stratosphere increase with height.

6. The Mesosphere and Thermosphere The third layer from the earth is the mesosphere. It is the coldest layer of the atmosphere. Here temperature decreases with height. The thermosphere is the layer farthest from the surface. It is the hottest layer. Temperatures here increase quickly with height. In fact, it can reach thousands of degrees Celsius.

7. The greenhouse effect Almost all of the sun’s energy never gets to earth. 3/10 of it is reflected into space. Another 3/10 is used to warm the air. The 4/10s left is used to warm the land and water. The atmosphere traps the heat like a greenhouse. Without the greenhouse effect, earth would reflect most of the sun’s energy and be too cold to have life.

8. Air masses If you could see air from space you would see large clumps of it forming, moving, and changing. These bodies of air are called air masses. Air masses have two properties that change depending on what it is over. They are humidity and temperature. Moist ones form over water. Ones that form over land are usually dry. Air masses that form near the poles are cold. If they form near the equator they are hot.

9. Fronts When two air masses meet it is called a front. That’s because they don’t mix. They form a border. Most weather happens by fronts. A cold front forms when a cold air mass catches up with a warm air mass. It pushes the warm air up. Thunderstorms usually occur along a cold front. A cold front is represented by a line and triangles on a map. Warm fronts occur when warm air masses catch up with cold air masses. The warm air mass pushes the cold air mass up. The temperature usually becomes warmer. Warm fronts are represented by a line and half circles.

10. Stationary Fronts Sometimes a front stops moving These are stationary fronts. They cause high amounts of snow. They also cause floods.

11. How is weather predicted? Meteorologists are scientists who study weather conditions. They have created tools for developing them. Thermometers measure temperature. Air pressure is measured by a barometer. A hygrometer measures humidity in an area. Scientists measure wind speed using anemometers. Wind direction is found using weather vanes or wind socks.

12. Mapping and Charting Weather By watching and measuring weather conditions, scientists keep track of all moving air masses. They record measurements on charts and maps and then predict the weather. A weather map can be any size. Big ones can cover countries, small ones can cover states or smaller areas. A weather map uses symbols to show the weather.

13. Types of clouds There are many types of clouds. A few of them are Cirrus, Cumulonimbus,Cumulus, Stratus,Stratocumulus,andAltocumulus. Cirrus are high clouds that are made up of ice crystals. The wind stretches them into long horseshoe or feather shapes. They usually go with cool, fair weather. Cumulonimbus clouds are large, dark rain clouds that are usually in cold fronts and bring thunder. cumulonimbus Cirrus

14. Cumulus and Stratus clouds Cumulus clouds are puffy, cotton ball like clouds that form by condensing, or water turning from a gas to liquid, at the middle layer of clouds. They are found on clear, warm days. Stratus clouds are a flat layer of low clouds. They usually bring rain and occur along warm fronts. Cumulus Stratus

15. Altocumulus and Stratocumulus Altocumulus clouds are thick blanket like clouds that usually means snow or rain, or at least cloudy skies. They are blue gray in color. Stratocumulus clouds are dark clouds that, like altocumulus clouds, usually mean rain or snow. These clouds are dark, water droplet clouds that stay at low or lower middle heights. Altocumulus Stratocumulus

16. Videos Cloud Types Song Videos http://cleanvideosearch.com/media/action/yt/watch?videoId=u3QwLYfgwP0 http://cleanvideosearch.com/media/action/yt/watch?videoId=ur0k7UDrrvg Weather Instruments Song Video http://cleanvideosearch.com/media/action/yt/watch?videoId=kBfaAN_tWW4

17. Extra Vocabulary • Water cycle- recycling of water. • Evaporation- a liquid changing to a gas. • Dew point- the temperature in which water vapor condenses. • Precipitation- rain, snow, sleet, or hail. • Moisture- the small amount of liquid that causes dampness.

18. Essential questions • Do we drink the same water that was on earth millions of years ago? • What form does water take on our earth? • What happens daily to water on earth? • How does water change from a solid to a liquid to a gas? • How does water change from a gas to a liquid to a solid? • How are clouds formed? • What is the water cycle? • What are forms of precipitation? • Why do we use the following instruments: rain gauge, hygrometer, thermometer, anemometer, barometer, and wind vane. • How do we distinguish between weather and climate? • Why do we use symbols on a weather map and what do they mean? • How do we know a weather forecast is accurate? • Where does water go in a drought? • Do we drink the same water that the dinosaurs drank?

19. Enduring understanding • The weather changes every day. • Water can be liquid or solid. • Water disappears. • Weather occurs daily. • Temperatures affect water.