| A | B |
|---|
| Absolute Humidity | The mass of water vapor in a given volume of air. |
| Absolute Instability | Occurs when the parcels temperature is greater than the ELR. |
| Absolute Stability | Occurs when the parcels temperature is less than the ELR. |
| Adiabatic Temperature Change | Temperature change to a parcel of air through the rising or sinking of the parcel. |
| Calorie | The amount of heat needed to raise 1 gram of water 1C. |
| Condensation | When water vapor becomes a liquid. |
| Conditional Instability | Occurs when a parcels temperature is in between the ELR. |
| Convective Lifting | Unequal heating of the Earth’s surfaces causes pockets of air to be warmed more than surrounding air becoming unstable and rising. |
| Convergence | When surface air meets, and increases its height to allow for the decreased area it occupies. |
| Deposition | Change in state when a gas converts directly to a solid. |
| Dew Point | The temperature which a parcel of air needs to cool to become 100% saturated. |
| Dry Adiabatic Rate | The rate at which an unsaturated parcel of air will cool as it rises. |
| Evaporation | Change in state when a liquid converts directly to a gas. |
| Freezing | Change in state when a liquid converts directly to a solid. |
| Front | The boundary between a warm air mass and a cold air mass. |
| Frontal Wedging | When cold dense air forces warm less dense air to rise and become unstable. |
| Humidity | General term used to describe the amount of water vapor in the air. |
| Hydrologic Cycle | The continuous movement of water from one form to another. |
| Hygrometer | Instrument used to measure relative humidity. |
| Latent Heat | Heat produced in a change in state but not a change in temperature. |
| Lifting Condensation Level | The point at which a parcel of air will become saturated and create a cloud and release latent heat. |
| Melting | Phase change when a solid becomes a liquid. |
| Mixing Ratio | The mass of water vapor in a unit mass of dry air. |
| Orographic Lifting | When terrains force parcels of air to move upward. |
| Psychrometer | An instrument with two thermometers and a data table to calculate the relative humidity. |
| Rain Shadow Desert | A desert that is the result of orographic lifting. |
| Relative Humidity | The ratio of the airs current water vapor compared to the total water vapor it could hold at a given temperature. |
| Saturation | The point when the air can hold no more water vapor. |
| Saturation Vapor Pressure | The pressure created by the addition of water vapor to air. |
| Stable Air | Cold air that resists movement upward. |
| Sublimation | Change in state when a solid converts directly to a gas. |
| Subsidence | When there is a general flow of air downward. |
| Transpiration | Process where plants release water into the air. |
| Unstable Air | Warm air that does not resist upward movement. |
| Wet Adiabatic Rate | The rate at which a saturated parcel of air will cool as it rises. |
