PART 1 1. ozone – a molecule of oxygen with three oxygen atoms (O3) 2. troposphere – from Earth’s surface up to about 12km; temperature decreases as you go higher; layer where most weather events occur 3. stratosphere – about 12km to 50km above Earth’s surface; temperature increases as you go higher (due to ozone layer); ozone layer is found here 4. mesosphere – about 50km to 85km above Earth’s surface; temperature decreases as you go higher 5. thermosphere – about 85km to 100km above Earth’s surface; temperature increases as you go higher (due to solar radiation) 6. heat – thermal energy transferred from one object to another 7. temperature – measure of the average kinetic energy of individual atoms or molecules in a substance 8. greenhouse effect – heating of Earth’s surface & atmosphere from absorption of solar radiation mostly from water vapor and carbon dioxide (CO2) 9. albedo – amount of solar radiation reflected off of a surface 10. isotherm – a line connecting points of equal temperature 11. precipitation – any form of water that falls from a cloud 12. evaporation – the change of state from a liquid to a gas 13. condensation – the change of state from a gas to a liquid 14. latent heat – energy absorbed or released during a change in state 15. humidity – water vapor in the air 16. saturated – air that contains the maximum amount of water vapor that it can hold at any given temperature and pressure 17. relative humidity – ratio of the actual amount of water vapor in a parcel of air compared to the amount of water vapor it can actually hold 18. dew point – temperature to which air has to be cooled in order to reach saturation 19. orographic lifting – pushing up of air by elevated terrain (such as mountains) 20. front – the boundary between two adjoining air masses having contrasting characteristics 21. temperature inversion – a thin layer in the atmosphere where temperature increases instead of decreases with height 22. condensation nuclei – tiny bits of material (such as dust) that serve as surfaces on which water vapor condenses 23. Words from Unit 1: convection, conduction, radiation PART 2 1. air pressure – the force exerted by the weight of a column of air above a given point 2. pressure gradient – amount of pressure change occurring over a given distance 3. Coriolis Effect – apparent deflective force of Earth’s rotation on all free-moving objects, including the atmosphere and oceans; to the right in the Northern Hemisphere 4. jet stream – fast (120-240 km/hr), high altitude winds 5. cyclones – low-pressure center characterized by a counterclockwise flow of air in the Northern Hemisphere 6. anticyclones – high-pressure center characterized by a clockwise flow of air in the Northern Hemisphere 7. trade winds – winds that blow almost constantly to the East; found between the Equator and 30o North and South 8. westerlies – winds that blow mostly from the West; found between 30o and 60o North and South 9. prevailing wind – a wind that consistently blows from one direction more than from another 10. monsoons – seasonal reversal of wind direction associated with large continents, especially Asia; winter = wind from land to sea, summer = wind from sea to land PART 3 1. air mass – a large body of air that is characterized by similar temperature and humidity at any given altitude 2. warm front – a front where a warm air mass overrides a retreating mass of cooler air 3. cold front – a front where a cold air mass pushes under a warmer air mass 4. stationary front – a front where neither air mass overtakes the other 5. occluded front – a front where a cold front overtakes a warm front 6. thunderstorm – a storm produced by a cumulonimbus cloud; always has thunder and lightening 7. tornado – small, very intense cyclonic storm with extremely high winds; usually form along cold fronts with severe thunderstorms 8. hurricane – a tropical cyclonic storm having winds greater than 119 km/hr; usually form over warm tropical waters in the mid to late summer in the Northern Hemisphere 9. storm surge – abnormal rise of the sea along a shore as a result of strong winds 10. global warming – an increase in the average temperatures of Earth and the atmosphere due in part to increased CO2 levels 11. weather – the state of the atmosphere at any given time and place 12. climate – observations of weather collected over many years that help describe a place or region