Atmospheric Water & Weather Flashcards
What is weather?
what’s happening now; what you get
What is climate?
long term weather conditions; what you expect
What are the unique qualities of water (6)?
- most common compound on Earth
- colorless, odorless, tasteless
- only substance on Earth which occurs in all three states
- expands as it freezes
- high specific heat
- phase change requires addition/absorption/release of energy
What is latent energy?
type of energy absorbed/released when water changes phases
What is evaporation?
liquid to gas
What is condensation?
gas to liquid
What is freezing?
liquid to solid
What is melting?
solid to liquid
What is sublimation?
solid to gas
What is deposition?
gas to solid
Which phase changes release latent heat?
evaporation, melting, sublimation
Which phase changes absorb latent heat?
condensation, freezing, deposition
What is humidity?
the amount of water vapor in the air
What is the relationship between heat and humidity?
warmer temperatures result in greater capacity for humidity because warm air has more enrgy to evaporate water
What is relative humidity?
ratio of the amount of water in atmosphere to how much water the atmosphere can contain
How does relative humidity change throughout the day?
amount of water stays the same but capacity for water increases due to increse in temperature, causing realtive humidity to drop
What is saturation?
point at which relative humidity hits 100%; results in condensation
What is dew point temperature?
temperature at which relative humidity hits 100%
Can you have a freeze without the formation of frost?
yes, if the temperature passes below freezing but is not low enough to hit the dew point
When does the highest relative humidity occur?
sunrise, at the lowest temperature
When does the lowest relative humidity occur?
midafternoon, at the highest temperature
What is specific humidity?
actual amount of water vapor in atmosphere
What are two instruments for measuring humidity?
haar hygrometer and sling psychrometer
What are air parcels?
bodies of air with specific temp. and humidity characteristics
What do rising air parcels do?
expand and cool (lower pressure)
What do sinking air parcels do?
compress and heat (higher pressure)
What is stability?
the tendency of an air parcel to rise, stay in place, or fall
What are unstable air parcels?
air parcel is warmer than surrounding air and rises until surround air is same temp. (results in clouds and precipitation)
What are stable air parcels?
air parcel stays in place or sinks (same or cooler than surrounding air)
What is the normal lapse rate?
average rate at which temp. decreases with in crease in altitude (3.5 F / 1,000 ft)
What is the environmental lapse rate?
actual lapse rate for local conditions
What are adiabatic rates?
rates at which moving air parcels cool off/heat up