Unit 3: Weather

1. What is the source of all energy in our atmosphere? Sun 2. List the solids that could be found in the atmosphere? Dust, pollen, salt 3. Define atmosphere. An atmosphere is a thin layer of air that forms a protective covering around the planet. 4. Which layer of the atmosphere contains the highest concentration of ozone? Stratosphere 5. List 4 characteristics of the troposphere. (What can I find in this layer?) Lowest layer; contains 99% of the water vapor; contains 75% of the atmospheric gases; Rain, snow, & clouds occur here.

6. What is the job of the ozone layer? Protects us from harmful UV radiation from the sun 7. What are the two major gases (with %) in the atmosphere? Nitrogen=78%; Oxygen=21% 8. On a hot summer day, you are lying on the beach and feel the sun’s warmth even though you cannot touch the sun. Which method of heat transfer is responsible for the warmth you feel? Radiation * Air Pressure/Air Masses/ Fronts 9. Why does cold air have high pressure? Why does warm air have low pressure? Cold air has high pressure because the particles pack together resulting in high density pressing down. Warm air has low pressure because the particles are spread apart resulting in low density. 10. Explain wind formation. (Describe the movement of air.) Wind results when two air masses collide that have a difference in pressure; the movement of air from an area of high pressure to an area of low pressure.

11. Explain how warm fronts form. Warm air is less dense than cold air; therefore, when a warm air mass moves into a cold air mass the warm air mass slides up and over the cold air leading to gentle rain or light snow. 12. Explain how a cold front occurs. Cold air is denser than warm air; therefore, when a cold air mass pushes under a worm air mass, forcing the warm air mass to rise. Explain how a stationary front occurs. Forms when warm and cold air meet and neither has the force to move the other...a standoff happens 13. Currents in the Atlantic Ocean flow from the equator where they are warmed towards areas to the Arctic Ocean where they are cooled. As they flow back towards the equator, what is the effect on the nearby land? The air over the nearby land is cooled by the cooler water as it flows nearby Storms 14. Define a hurricane. A tropical cyclone that forms over warm ocean water as a low pressure system; may last a week or more; loses strength as it crosses land 15. In a thunderstorm, which happens first, thunder or lightning? Lightning

16. Name the large, dark clouds that produce different types of severe weather such as thunderstorms and tornadoes. Cumulonimbus 17. Define tornadoes. Rapidly whirling, funnel- shaped cloud, reaching from the storm cloud to the ground; winds at different heights in cumulonimbus clouds Global Winds 18. Which global wind system is responsible for moving weather across North America? Prevailing Westerlies 19. What is the Coriolis effect? Coriolis Effect: When the rotation of Earth on its axis causes moving air and water to appear to turn to the right (clockwise) North of the equator and to the left (counter clockwise) South of the equator.