Earth Science Chapter 18
what is fog?
"a cloud with its base at or very near the ground"
what is the cause of frontal wedging?
"a front produces, and the cooler air acts as a barrier which the warm air rises."
what must happened for precipitation to form?
"cloud droplets must grow in volume by roughly one million times"
what is the cause of orographic lifting?
"mountains block airflow"
what are the four ways air can rise?
"orographic lifting, frontal wedging, convergence, and localized convective lifting"
what is the cause of lifting from convergence?
"whenever air in the lower atmosphere flows together, lifting results"
Formation of precipitation in cold clouds is called the ______________ process
Bergeron
What is the difference between humidity and relative humidity?
Humidity is the measure of water vapor in the air. Relative humidity is the humidity level compared to the actual capacity of the area measured.
Why does a parcel of air expand as it rises upward through the atmosphere?
It expands because "the atmospheric pressure decreases."
What happens when air that has reached its dew point is cooled further?
Once air is cooled further than the dew point, they become clouds, fog, or dew because the overflow of water vapor "condenses."
what is produced when two air masses collide?
a front
describe a temperature inversion
air temperature increases with height
name the low clouds a. stratus b. altostratus c. stratocumulus d. nimbostratus
c. stratocumulus d. numbostratus
the three types of __________ clouds are cirrus, cirrostratus, and cirrocumulus
cirro
what is the typical resulting weather pattern from convergence?
cloud development and precipitation
what is the typical resulting weather pattern for localized convective lifting?
cloud formation and precipitation
what is the typical resulting weather pattern because of orographic lifting?
clouds and precipitation
what is the typical resulting weather pattern from frontal wedging?
clouds and rain
When a parcel of air reaches its dew point, the process of _______________ begins.
condensation
A parcel of air that is less dense than the surrounding air is __________ and will tend to rise
cooler
When a parcel of air is allowed to expand, it ______
cools
what is the best word that describes water in the liquid state below 0ºC? a. supersaturated b. coalesced c. saturated d. supercooled
d. supercooled
air temperature increases
decreases
water vapor is removed
decreases
what a parcel of air is cooled to the temperature at which it is saturated, it has reached its _____ _________
dew point
A sling psychrometer works because the amount of cooling that occurs in the wet bulb is directly proportional to the __________ of the air
dryness
Opposite change of state for condensation
evaporation
true or false? The rate of heating or cooling of saturated air is the dry adiabatic rate.
false
true or false? in warm clouds, raindrops form by the Bergeron process
false
true or false? unstable air tends to remain in its original position
false
describe a cumulus cloud
fluffly, round, (like a cotton ball)
ice pellets with multiple layers
hail
describe a cirrus cloud
high, wispy, thin
Match each situation to its change in relative humidity. (Increases, no change, or decreases) Water vapor is added
increases
air temperature decreases
increases
After a parcel of air rises past the condensation level, the rate of cooling decreases because of the release of _______ ______
latent heat
freezing
melting
drops of water that fall from a cloud and have a diameter of at least 0.5 mm
rain
what does a hygrometer measure?
relative humidity
for condensation to occur, air must be _______________
saturated
hail, sleet, or rain? small particles of ice
sleet
deposition
sublimation
true or false? Saturated warm air contains more water vapor than saturated cool air.
true
true or false? above the ground, tiny particles called condensation nuclei serve as surfaces for water-vapor condensation
true
true or false? clouds are classified based on form and height
true
true or false? fogs can be formed by cooling or by evaporation
true
true or false? localized convective lifting produces thermals that lift birds to great heights
true
what is the cause of lifting for localized convective lifting?
unequal heating of earth
clouds associated with lifting of _________ air often produce thunderstorms
unstable
The most important gas in atmospheric processes
water vapor
how can you tell from the name of a cloud if it is a middle-range cloud?
you can tell if it is a middle-ranged cloud because of the prefix "alto" which comes before the cloud name
