ch.5 Flashcards
Melting
Melting: solid => liquid
Evaporation
Evaporation: liquid => gas
Condensation
Condensation: gas => liquid
Freezing
Freezing: liquid => solid
Sublimation
Sublimation: solid => gas
Deposition
Deposition: gas => solid
Latent heat:
Latent heat: heat used to melt or evaporate a substance, but does not produce a temperature change
Absolute humidity
Absolute humidity: mass of water vapor in a given volume of air
Mixing ratio
Mixing ratio: mass of water vapor in a unit of air compared to the mass of the remaining dry air
Relative humidity
Relative humidity: ratio of the amount of water vapor actually in the air compared to the maximum amount of water vapor required for saturation at that particular temperature and pressure
Dew Point
Dew point: temperature at which air would have to be cooled for saturation to occur
Dew Point vs. Relative Humidity
Dew Point better indicator of moisture because if moisture remains constant but air temperature changes, relative humidity will change
The closer the dew point and air temperature are to one another => higher relative humidity
The farther the dew point and air temperature are from one another => lower relative humidity
Adiabatic process
Adiabatic process: temperature changes in which no heat is added or subtracted
Air parcel rising => expansion and cooling
Air parcel sinking => compression and warming
Orographics
Forcing air above a mountain barrier
Enhanced precipitation on windward side
Rain shadow effect on leeward side
Frontal Wedging
Displacement of one air mass over another
Cold fronts, warm fronts, and other boundaries
Convergence
Inflow of air => air rises and cools adiabatically
Convection
Localized convection => isolated to scattered afternoon thunderstorms during the summer
Absolute Instability
Environmental lapse rate > dry adiabatic lapse rate
Air parcel remains warmer than its surrounding environment whether it is unsaturated or saturated
Air parcel will continue to rise once lifted
Conditional Instability
Environmental lapse rate is between the dry and wet (saturated) adiabatic lapse rates
If air parcel stays unsaturated, then it will remain cooler than the surrounding environment and resist lifting
If air parcel becomes saturated and can be lifted sufficiently [level of free convection (LFC)], then it will continue to rise
