Deck 6: Cloud Development and Forms

Question 1

Conditionally unstable air:

A)contains a mixture of absolutely stable air and absolutely unstable air.
B)moves through an environmental lapse rate that is between the dry adiabatic lapse rate and the wet adiabatic lapse rate.
C)always has a negative buoyance.
D)rarely provides precipitation.

Answer 1

B

Question 2

You would most likely expect a rain shadow on the:

A)east side of the Cascade Mountains in the Pacific Northwest.
B)west side of the Sierra Nevada Mountains.
C)west side of the Andes.
D)west side of the Coast Range in California.

Answer 2

A

Question 3

Fronts:

A)are rarely involved with cloud formation.
B)have substantial temperature gradients at their boundaries.
C)are best imagined as vertical walls of air.
D)come in three major varieties-cold, warm, and mixed.

Answer 3

B

Question 4

Orographic uplift is usually associated with rising air:

A)over the great plains.
B)along the Gulf of Mexico coast.
C)over oceans.
D)along the windward side of mountains.

Question 5

Frontal lifting is often likened to a conveyor belt and is referred to as:

A)overrunning.
B)trans-continental uplift.
C)frontal overload.
D)isobaric upheaval.

Question 6

Absolutely stable air:

A)has a wet adiabatic lapse rate that is greater than the environmental lapse rate.
B)will have a positive buoyancy.
C)needs a push to rise, but will continue rising once it starts moving.
D)is typically warmer than its surroundings.

Question 7

There are ________ ways to lift air in the atmosphere.

A)many
B)three
C)six
D)five
E)four

Question 8

This is the cause of most thunderstorms:

A)convergent lifting.
B)frontal lifting.
C)orographic lifting.
D)localized convective lifting.

Question 9

Sometimes,horizontal transition zones exist in which great temperature differences occur across relatively short distances.These transition zones are called:

A)fronts.
B)jet streams.
C)anti-cyclones.
D)inversions.

Question 10

This occurs when a large mass of cold air slides underneath a large mass of warm air:

A)orographic lifting.
B)convergence.
C)frontal lifting.
D)convective lifting.

Question 11

When the environmental lapse rate exceeds both the dry adiabatic lapse rate and the wet adiabatic lapse rate of a parcel of air,that air parcel contains:

A)absolutely stable air.
B)conditionally unstable air.
C)absolutely unstable air.
D)air that cannot reach the lifting condensation level.

Question 12

Static stability:

A)is similar to buoyancy.
B)is unrelated to adiabatic cooling.
C)is unaffected by the temperature of the air parcel.
D)is unaffected by the density of the air parcel.

Question 13

Ultimately,the buoyancy of a rising air parcel is dependent upon its:

A)composition.
B)volume.
C)concentration of water vapor.
D)rate of cooling relative to the surrounding air.

Question 14

Frontal lifting:

A)is not related to temperature differences between air masses.
B)leads to increased pressure on the warm front.
C)can act in a way that is analogous to orographic lifting.
D)is most pronounced when a cold front meets a cold front.

Question 15

Orographic uplift:

A)rarely leads to clouds forming above the top of the hill or mountain.
B)creates clouds that usually have the same height, regardless of time or place.
C)provides equal amounts of precipitation on both sides of a mountain range.
D)can create cumulus clouds.

Question 16

This type of air neither rises on its own following an initial lift nor sinks back to its original level.

A)statically unstable air
B)statically neutral air
C)statically stable
D)none of the above

Question 17

All of the following statements about convergent lifting are true,except:

A)it requires a difference in pressure between two areas with horizontal separation.
B)it typically proceeds diabatically.
C)it leads to the rising of air.
D)it causes wind.

Question 18

This occurs when a mountain range forces air to rise:

A)frontal lifting.
B)convergence.
C)localized convective lifting.
D)orographic lifting.

Question 19

This type of air will keep rising after an initial upward push:

A)statically stable air.
B)statically unstable air.
C)statically neutral air.
D)air that is colder and denser than surrounding air.

Question 20

In which state would orographic lifting be most important?

A)Louisiana
B)Florida
C)Kansas
D)Colorado

Question 21

The lower atmosphere is most likely to have the steepest environmental lapse rate at this time:

A)sunrise.
B)mid-day.
C)sunset.
D)midnight.

Question 22

Inversions:

A)are characterized by an increase in temperature with altitude.
B)increase the positive buoyancy of most air masses that enter them.
C)have no significant effect on fog formation.
D)are typically unstable.

Question 23

A rising parcel of unstable air:

A)can eventually escape into space.
B)can rise well into the mesosphere.
C)cannot rise very far above the tropopause.
D)will not be slowed by entrainment.

Question 24

The level of free convection is where:

A)moisture content in the atmosphere becomes too heavy to lift.
B)air becomes negatively buoyant and rises by itself.
C)air becomes positively buoyant and rises by itself.
D)usually occurs only early in the morning.

Question 25

Clouds are least likely to occur in the:

A)mesosphere.
B)troposphere.
C)ionosphere.
D)stratosphere.

Question 26

Which of the following causes unstable air to keep lifting?

A)ascent into a layer of stable air
B)entrainment
C)inversions
D)ascent into a layer of unstable air

Question 27

The level of free convection:

A)is relevant only when discussing absolutely unstable air.
B)occurs below the point where a rising air parcel is cooler than its surroundings.
C)is unrelated to temperature of either the air parcel or its surroundings.
D)is above the lifting condensation level.

Question 28

If air becomes progressively warmer and more buoyant than the surrounding air,it is said to be:

A)absolutely stable.
B)absolutely unstable.
C)neutral.
D)conditionally unstable.

Question 29

Inversions are detrimental to developing storm systems because:

A)they encourage instability.
B)they cap convective development
C)they increase entrainment.
D)they seriously alter the horizontal moisture profile of the atmosphere.

Question 30

Subsidence inversions:

A)are less important than frontal inversions.
B)often lead to increased pollution in Los Angeles.
C)are common on the windward slopes of large mountain ranges.
D)are common on the western margins of large high-pressure areas.

Question 31

Air that must be lifted before it becomes unstable means that the atmosphere is:

A)absolutely stable.
B)absolutely unstable.
C)neutral.
D)conditionally unstable.

Question 32

One of the fastest ways to destabilize an atmosphere is to:

A)allow it to sink.
B)advect it over a cold surface.
C)warm it from the top down.
D)lift it.

Question 33

The advection of cold or warm air can occur at:

A)low levels.
B)mid-levels.
C)upper-levels.
D)all of the above

Question 34

One of the most detrimental effects on developing cumulus clouds is:

A)the addition of more moisture to the developing cloud.
B)an injection of warm air into the center of the developing cloud.
C)a weak vertical atmospheric wind profile.
D)entrainment.

Question 35

An inversion:

A)implies that a layer of air is unstable.
B)means that a layer of air is overturning.
C)indicates that a layer of air is stable.
D)has no significance as far as a meteorologist is concerned.

Question 36

Entrainment:

A)feeds cloud growth.
B)usually increases the positive buoyancy of unstable air.
C)warms cloud margins.
D)brings unsaturated air into clouds.

Question 37

Which of the following inversions are more extensive and meteorologically important?

A)radiation inversion
B)frontal inversion
C)subsidence inversions
D)none of the above

Question 38

This is the least important factor that can influence environmental lapse rate:

A)heating of the lower atmosphere.
B)advection of cold and warm air at different levels.
C)advection of an air mass with a different environmental lapse rate.
D)changes in the amount and type of air-borne pollutants.

Question 39

Inversions:

A)are found only with frontal systems.
B)can be found at any level of the atmosphere.
C)are found only near the surface early in the morning.
D)indicate that rain could occur in a few days.

Question 40

This the most important mechanism for stopping the rise of unstable air parcels:

A)encountering a layer of stable air.
B)entrainment.
C)friction.
D)reaching the lifting condensation level.

Question 41

Altostratus clouds:

A)scatter a substantial portion of sunlight back into space.
B)allow enough light through to throw sharp shadows on the ground.
C)form halos around the Sun and the Moon.
D)form a series of rows of puffy clouds.

Question 42

Cumulonimbus:

A)can span nearly the entire troposphere.
B)are prevented by the tropopause from entering the stratosphere.
C)are typically composed of ice near the bottoms of the clouds.
D)provide smooth flying for commercial airliners.

Question 43

The English naturalist Luke Howard devised the first widely used cloud classification system in

A)1803.
B)1903.
C)1667.
D)1856.

Question 44

Noctilucent clouds are:

A)the same as nacreous clouds, but they exist at a lower elevation.
B)found in the mesosphere.
C)most easily observed in summer.
D)most easily observed near the equator.

Question 45

Lenticular clouds:

A)have linear shapes.
B)usually form over gently sloping plains.
C)result in a substantial net accumulation of moisture within the clouds.
D)are the result of waves in the air flow.

Question 46

Which of the following pairs of clouds are the primary precipitation-producing ones?

A)stratus and nimbostratus
B)nimbostratus and cumulonimbus
C)stratocumulus and cumulonimbus
D)altostratus and nimbostratus

Question 47

Cumuliform clouds:

A)are typically much wider than they are tall.
B)form in absolutely stable air conditions.
C)have very weak vertical velocities within them.
D)typically have higher water content than stratiform clouds.

Question 48

Stratus clouds:

A)form only from the adiabatic lifting of air.
B)can form sheets up to several hundred miles long.
C)have a high-water content.
D)are a most responsible for colorful sunsets.

Question 49

Middle clouds:

A)are prefixed by "cirro."
B)can often be found within a kilometer of the ground.
C)include cumulonimbus clouds.
D)are composed of liquid droplets.

Question 50

This is not a form of low cloud:

A)stratus.
B)nimbostratus.
C)nimbocumulus.
D)stratocumulus.

Question 51

Clouds that form downwind from mountain barriers and have a curved shape are called:

A)streamers.
B)lee-side clouds.
C)lenticularus clouds.
D)contrails.
E)none of the above

Question 52

High clouds:

A)have a typical ceiling around 4500 meters.
B)are composed of ice crystals.
C)include altostratus clouds.
D)have a fairly large water content.

Question 53

Contrails:

A)are not legitimate cloud forms.
B)are too high in the atmosphere to impact surface weather conditions.
C)are caused by the warm, moist jet aircraft exhausts.
D)almost never last for any appreciable length of time.

Question 54

Which of the following are not in the High Cloud group?

A)altostratus
B)cirrus
C)cirrostratus
D)cirrocumulus

Question 55

Stratocumulus clouds are considered:

A)high clouds.
B)middle clouds.
C)low clouds.
D)clouds with extensive vertical development.

Question 56

Hail formation is associated with:

A)cumulonimbus.
B)nimbostratus.
C)stratocumulus.
D)cumulus.

Question 57

Suppose you are a pilot.What is the safest option as you fly toward a cumulonimbus?

A)fly through it
B)fly around it
C)land the plane
D)use it as an opportunity to refuel

Question 58

Clouds that are high and are always composed entirely of ice crystals are:

A)stratus.
B)thunderheads.
C)alto.
D)cirrus.
E)nimbus.

Question 59

Cumulus congestus:

A)are formed in stable air, typically in inversion layers.
B)have large temperature differences between the bottom and top.
C)are composed entirely of supercooled water droplets.
D)do not have temperatures below about -4 degrees Celsius.

Question 60

Cirrostratus clouds:

A)are more likely to herald coming precipitation than are cirrocumulus clouds.
B)contain a mixture of ice crystals and supercooled water droplets.
C)are responsible for the halo effect.
D)are formed by wind shear.

Question 61

________ clouds need not form from the lifting of air parcels.

Question 62

What are the important ways in which unstable air can be prevented from rising indefinitely?

Question 63

The cloudiest city in the U.S.is:

A)Lansing, Michigan.
B)Chicago, Illinois.
C)Juneau, Alaska.
D)San Francisco, California.

Question 64

The lower atmosphere typically has a steeper environmental lapse rate in the middle of the day because

A)the surface warms more slowly than the air aloft
B)the surface warms more rapidly than the air aloft
C)water tends to evaporate at the surface, releasing latent heat
D)the air aloft tends to absorb more shortwave radiation

Question 65

Ascending parcels of unstable air seldom extend above the tropopause because

A)the troposphere is extremely stable
B)the troposphere is extremely unstable
C)the stratosphere is extremely stable
D)the stratosphere is extremely unstable

Question 66

This instrument is used to measure cloud heights and coverage.

A)ceilometer
B)barometer
C)hygrometer
D)radiosonde

Question 67

Explain why cumulus clouds have clearly defined boundaries.

Question 68

Which of the following causes unstable air to stop rising?

A)additional warming of the surface
B)additional cooling of the air aloft
C)ascent into a stable layer
D)adiabatic cooling

Question 69

An unstable air parcel that rises through a stable layer does not come to a screeching halt because

A)it takes time for condensation to occur
B)adiabatic cooling is slower in stable air
C)the rising air has upward momentum
D)the stable layer may not have any liquid water droplets

Question 70

The cloudiest city in Canada is in the province of:

A)British Columbia.
B)Yukon.
C)Quebec.
D)Labrador.

Question 71

Entrainment is especially active along the edges of growing clouds because

A)saturated air enters rising air parcels, causing evaporation
B)unsaturated air enters rising air parcels, causing evaporation
C)saturated air enters rising air parcels, preventing condensation
D)saturated air enters rising air parcels, increasing turbulence

Question 72

Which of the following increases entrainment of ambient air into a rising air parcel?

A)adiabatic cooling
B)adiabatic warming
C)greenhouse gases
D)turbulence

Question 73

The environmental lapse rate typically decreases at night because

A)the surface absorbs more longwave radiation than the air aloft
B)the surface absorbs less longwave radiation than the air aloft
C)the surface cools more slowly than the air aloft
D)the surface cools more rapidly than the air aloft

Question 74

________ are thin and wispy clouds composed of ice.

Question 75

The greatest amount of mass contained in a cloud is

A)liquid water.
B)ice.
C)aerosols.
D)air.

Question 76

List the subcategories of high-,middle- and low-cloud types.

Question 77

The sunniest city in North America is:

A)Miami, Florida.
B)Yuma, Arizona.
C)Las Vegas, Nevada.
D)Santa Fe, New Mexico.

Question 78

An unstable air parcel that rises through a stable layer eventually returns to its original level because

A)its density is less than that of the surrounding air
B)its density is greater than that of the surrounding air
C)its density remains the same despite vertical motions
D)vertical motions cannot change the air's density

Question 79

The amount of clouds in the sky is called ________.

Question 80

The most common mechanism of cloud formation is:

A)adding water vapor to the air.
B)mixing warm moist air with cold air.
C)lowering the air temperature to the dew point by adiabatic cooling of rising air.
D)none of the above