| A | B |
|---|
| troposphere | the layer of Earth's atmosphere closest to the ground; contains clouds, smog, weather, and 75 percent of atmospheric gases |
| ionosphere | a layer of Earth's atmosphere, where ions and free electrons absorb AM radio waves during the day and reflect them back toward Earth at night |
| ozone layer | a layer of the stratosphere with a high concentration of ozone; protects living things by absorbing ultraviolet radiation from the sun |
| ultraviolet radiation | a type of energy that comes to Earth from the sun and is mostly absorbed by the ozone layer; rays can damage skin and cause cancer and other health problems |
| chlorofluorocarbons | a group of chemicals used as refrigerants and aerosol spray propellants; chlorofluorocarbons destroy ozone molecules |
| radiation | the transfer of energy through matter or space by electromagnetic waves |
| conduction | the transfer of heat that occurs when molecules collide |
| hydrosphere | all the water that occurs at Earth's surface |
| water cycle | the continuous movement of water between Earth's surface and the atmosphere through evaporation, condensation, and precipitation |
| Coriolis effect | the effect of Earth's rotation on the movement of air masses; changes the direction of the air flow |
| jet stream | narrow wind belts occuring near the top of the troposphere |
| sea breeze | wind blowing from sea to land during the day when the sun warms the land faster, and cool air from above the water forces the warm air above the land to rise |
| land breeze | wind blowing from land to sea at night because the land cools faster and cool air over the land moves out over the sea |
