| A | B |
|---|
| air pressure | the force of air molecules pushing on an area |
| barometer | an instrument that measures air pressure in the atmosphere |
| wind | the horizontal movement of air caused by differences in air pressure |
| global wind | wind that travels long distances in steady patterns over several weeks |
| Coriolis effect | the influence of Earth's rotation on objects that move over Earth |
| jet stream | a wind that flows in the upper troposphere from west to east over vast distances at great speeds |
| monsoon | a wind that changes direction with the seasons |
| evaporation | the process by which liquid changes into gas |
| condensation | the process by which gas changes into a liquid |
| humidity | the amount of water vapor in air |
| saturation | a condition of the atmosphere in which the rates of evaporation and condensation are equal |
| relative humidity | the comparison of the amount of water vapor in the air with the maximum amount of water vapor that can be present at that temperature |
| dew point | the temperature at which air reaches saturation |
| sleet | small pellets of ice that form when rain passes through a layer of cold air and freezes before hitting the ground |
| hail | layered lumps or balls of ice that fall from cumulo-nimbus clouds |
| acid rain | rain that has become more acidic than normal due to pollution |
