1. EARTHS SYSTEMS

2. ATMOSPHERE Invisible layers of air primarily made up of Nitrogen (75%), Oxygen (20.9%), and Argon (.9%) gases

3. GREENHOUSE EFFECT Radiation from the sun is reflected by earth and then bounced into the atmosphere where the water particles in the air trap the heat; the water particles remain in the troposphere causing the lowest layer of atmosphere to be warmer

4. TROPOSPHERE Zone where weather occurs; a dense layer of air in which molecules are fueled by sunlight and create energy for weather

5. CORIOLIS EFFECT Affects the direction of winds; makes things appear to move in a curved path due to the Earth spinning

6. CUMULUS CLOUDS Moist air collects rapidly over a small area Cumulonimbus clouds cause thunderstorms

7. STRATUS Air rising gently over a large area and then cools slowly; makes sunlight seemed filtered; they contain ice crystals that can make the sun or moon appear to have a halo Stratonimbus clouds cause storms

8. CIRRUS High in the atmosphere and look wispy; they form when water vapor condenses directly into ice crystals

9. AIR MASSES Large areas of air with the same temperature and moisture levels of the surface

10. COLD AIR MASS Produces cold weather

11. WARM AIR MASS Produces warm weather

12. COLD FRONT Leading edge of a cold air mass in which the cold air and warm air move towards each other and the warm air rises These fronts bring snow, thunderstorms, and heavy rains

13. WARM FRONT Leading edge of a warm air mass where cold air and warm air move in the same direction but then the warm air rises These bring rainy weather followed by clear weather

14. LOW PRESSURE SYSTEM Causes cloudy and rainy weather; rapid low pressure changes cause storms

15. HIGH PRESSURE SYSTEM Causes clear and sunny weather

16. BAROMETER Measures the pressure of air pushing down on the tube of mercury

17. WIND VANE Measures the direction of the wind

18. ANEMOMETER Measures wind speed

19. RAIN GAUGE Measures the amount of rain

20. OCEAN CURRENTS Large rivers of water flow through the ocean Cold Currents- run deep below the surface and creep along the bottom of the ocean until they reach the tropics Warm Currents- water heated by the sun and are pushed along by steady winds from the equator

22. JET STREAM The jet stream is a fast flowing, river of air found in the atmosphere at around 12 km above the surface of the Earth just under the troposphere. It flows west to east.

23. GULF STREAM The warm current that flows from the equator; it originates in the Gulf of Mexico and runs past the east coast of the United States towards Newfoundland

24. Hemisphere Half of the Earth divided by an imaginary line Northern Hemisphere and Southern Hemisphere are divided by the equator Western and Eastern Hemispheres are divided by the prime meridian

25. Latitude A geographical coordinate that tells where something is located in relationship to the distance north or south from the equator Equator is at 0 degrees latitude

26. Global Wind Patterns They are named by the direction which they blow Polar Easterlies- Located between 60 and 90 degrees latitude and blow irregularly from the east and north Prevailing Westerlies- Located between 30 and 60 degrees (US) and blow from the west to the east; cause most of the weather in the US Trade Winds- Located between 0 and 30 degrees; blow from the northeast towards the equator