Ch. 20 Quiz Flashcards
the mass of water vapor contained in a given volume of air
absolute humidity
an instrument that measures relative humidity with two identical thermometers with a wet wick attached to the end of one thermometer
psychrometer
The dew point is the temperature at which the rate of condensation ___ the rate of evaporation.
equals
If the temperature stays the same and the air becomes more moist, the relative humidity will ___.
increase
What must be present in order for clouds to form?
condensation nuclei
the process in which the temperature of an air mass decreases as the air mass moves over a cold surface
advective cooling
What does upslope fog form through?
lifting and cooling
The base of the clouds marks the ___.
condensation level
precipitation in the form of lumps of ice
hail
What’s the diameter of a normal raindrop?
between 0.5- 5 mm
What can form if rain falls through a layer of freezing air near the ground?
sleet
the most common form of solid precipitation
snow
the condensation that occurs when air comes into contact with grass and cools
dew
results from the nightly cooling of Earth
radiation fog
process where water vapor changes into a liquid
condensation
cover large areas of sky and often block out the sun
stratus clouds
have the highest altitude of any cloud in the sky
cirrus clouds
process where fast-moving molecules escape from a liquid to form water vapor
evaporation
introduces condensation nuclei into a cloud
cloud seeding
the energy absorbed or released by a substance during a phase change
latent heat
combines small cloud droplets into large droplets
coalescence
form at low altitudes with a top that resembles cotton balls
cumulus clouds
process where a solid changes directly into a gas
sublimation
cools a substance without changing its state
supercooling
forms along the coasts when warm, moist air moves across a cold surface
advection fog
