| Term | Definition |
|---|---|
| Weather | The state of the atmosphere at a certain time and place |
| Climate | The year-round weather typical of a certain place |
| Meteorology | the study of weather and of the atmospheric conditions that produce weater |
| Meteorologists | Forecast weather conditions |
| What three major factors work together to cause the earth's variable weather? | Heat energy, uneven distribution of heat energy, and water vapor in the atmosphere |
| Precipitation | The water that falls to the earth, including rain, sleet, hail, and snow |
| Melting | The process of going from a solid to a liquid |
| Freezing | In which molecules of a liquid lose enough energy to become "locked" in fixed positions |
| Evaporation | The process of liquid becoming gas |
| Condensation | If molecules in water vapor lose enough energy they will return to a liquid state in this process |
| Saturated | Air in which the water in the air is evaporating at the same rate that it is condensing |
| Humidity | The amount of water vapor in air |
| Relative humidity | The ratio of the actual humidity to the humidity of saturated air under the same conditions |
| Dew point | the temperature in which air becomes saturated |
| Water vapor, under ordinary conditions, will not turn into liquid water without what? | A surface to condense upon |
| Dew | The water vapor in the air that touches the cooler ground condenses into these drops of water |
| Frozen Dew | Occurs when temperatures drop below freezing after dew has formed, making the the dew freeze |
| Condensation nuclei | Microscopic particles, such as dust, soot, smoke, and sea salt, that are floating in the atmosphere |
| What do condensation nuclei serve as? | as the center that water vapor condenses onto |
| Frost point | Occurs when the dew point of water is below the freezing point of water |
| Deposition | The process of the air's water vapor skipping the liquid stage by changing directly into a crystal of ice on a surface |
| What some scientists call deposition | Sublimation |
| Water vapor is super cooled when what? | its temperature is below the freezing point |
| Ice deposits | Frost |
| Water vapor in air that drops below the frost point will remain super cooled until it can crystallize onto microscopic particles known as ___ ___. | Freezing nuclei (or ice nuclei) |
