| A | B |
|---|
| aerosol | solids, such as dust, salt, pollen, and liquid drops that are suspended in the air |
| atmosphere | layer of gases surrounding earth that protects living things from harmful doses of ultraviolet radiation |
| dew point | tempeature at which air is saturated and condensation can occur |
| front | boundary that develops when air masses of different temperatures collide; can be cold, warm, stationary, or occluded |
| humidity | amount of water vapor in the atmosphere |
| hurricane | large storm that begins as a low pressure area over tropical oceans |
| precipitation | occurs when drops of water or crystals become too large to be suspened in a cloud and fall in the form of rain |
| relative humidity | measure of the amount of water vapor in the air compared with the amount that could be held at a specific temperature |
| tornado | violent whirling wind that travels in a narrow path over land |
| troposphere | layer of the atmosphere closest to Earth's surface |
| water cycle | never-ending cycle in which water circulates betwen Earth's surface and the atmosphere |
| weather | current condition of the atmosphere |
| air mass | large body of air that develops over a particular region of Earth's surface |
