Deck 4: Moisture and Atmospheric Stability

Question 1

Water vapor constitutes about this much of the atmosphere by volume.

A)0-4 percent
B)0-12 percent
C)0-100 percent
D)4-25 percent
E)4-12 percent

Answer 1

A

Question 2

The attractive forces between the hydrogen atoms in one water molecule and the oxygen atoms in another molecule are known as:

A)water bonds
B)liquid bonds
C)hydrogen bonds
D)dark forces

Answer 2

C

Question 3

Refer to the diagram of a simple parcel above.What would the absolute humidity be if the volume were to double?

A)5 g/m³
B)20 g/m³
C)2)5 g/m³
D)The absolute humidity would remain unchanged.

Answer 3

A

Question 4

Which of the following requires the GREATEST RELEASE of latent heat energy into the atmosphere?

A)melting of 1 gram of water
B)freezing of 1 gram of water
C)evaporation of 1 gram of water
D)condensation of 1 gram of water

Question 5

Refer to the diagram of a simple parcel above.What is the absolute humidity of this parcel?

A)0)2 g/kg
B)10 g/m³
C)2 g/m³
D)5 g/kg

Question 6

Evaporation is a process which tends to keep temperatures cooler where it occurs.This is because the atmosphere:

A)increases the outgoing radiation.
B)reduces the absorption of solar energy.
C)increases the reflection of solar energy.
D)uses energy to change the phase of water instead of increasing air temperature.
E)increases the specific heat.

Question 7

The heat released when water vapor condenses to form a cloud or when liquid droplets freeze in a cloud:

A)makes the air heavier.
B)adds water to the cloud.
C)cools off the cloud.
D)evaporates more water.
E)helps the cloud to rise higher.

Question 8

All of the following are properties that make water unique among other substances on Earth EXCEPT:

A)water does not participate easily in hydrogen bonding.
B)water's solid phase is less dense than its liquid phase.
C)water exists naturally in all three phases (solid,liquid,vapor)and changes easily from one to another.
D)water is able to store large quantities of heat.

Question 9

Which of the following processes requires the highest RELEASE of energy from the water molecules?

A)melting
B)freezing
C)condensation
D)deposition

Question 10

Refer to the diagram of a simple parcel above.What additional information would you need in order to be able to calculate the relative humidity of this parcel?

A)air pressure inside the parcel
B)temperature outside of the parcel
C)current temperature/capacity to hold water vapor inside the parcel
D)current vapor pressure inside the parcel

Question 11

As liquid water is evaporated into the atmosphere,heat energy is:

A)absorbed by the remaining liquid.
B)given off by the water vapor.
C)released by the evaporating water.
D)absorbed by the evaporating water.
E)absorbed by the surrounding air.

Question 12

Refer to the diagram of a simple parcel above.What would the mixing ratio be if the volume were to double?

A)5 g/m³
B)20 g/m³
C)2)5 g/kg
D)The mixing ratio would remain unchanged.

Question 13

About what percent of Earth's water can be found in the oceans?

A)97%
B)90%
C)70%
D)53%

Question 14

The amount of water vapor in the air (by volume)usually does not exceed:

A)4 percent.
B)14 percent.
C)100 percent.
D)28 percent.
E)40 percent.

Question 15

The two changes of state that are the most important part of the water cycle for the atmosphere would be:

A)condensation,freezing.
B)condensation,melting.
C)melting,sublimation.
D)melting,freezing.
E)evaporation,condensation.

Question 16

? = The formula shown above defines the humidity measure known as:

A)the mixing ratio
B)absolute humidity
C)vapor pressure
D)relative humidity

Question 17

Saturation is best defined as:

A)a mixing ratio of at least 100 g/kg.
B)equal numbers of water molecules evaporating from and condensing into a water surface.
C)the point when water molecules completely stop evaporating from a water surface.
D)a vapor pressure greater than 1000 mb.

Question 18

? = The formula shown above defines the humidity measure known as:

A)the mixing ratio.
B)absolute humidity.
C)vapor pressure.
D)relative humidity.

Question 19

Refer to the diagram of a simple parcel above.What is the mixing ratio of this parcel?

A)10 g/m³
B)2 g/m³
C)0)2 g/kg
D)5 g/kg

Question 20

In which phase do water molecules have the lowest kinetic energy?

A)vapor
B)liquid
C)ice
D)It has the same kinetic energy in all three phases.

Question 21

An instrument used to measure relative humidity is called a:

A)hygrometer.
B)hydrometer.
C)humidimeter.
D)aquimeter.

Question 22

The air in Great Falls,Montana has a temperature of 5°C and a relative humidity of 50%.On the same afternoon,the air in Palm Springs,California has a temperature of 25°C and a relative humidity of 50%.What can be said about the amount of vapor in the air at these two cities?

A)Palm Springs will have a higher vapor content than Great Falls.
B)Great Falls will have a higher vapor content than Palm Springs.
C)Great Falls and Palm Springs will have the same vapor content.

Question 23

The capacity of the air to hold water vapor:

A)increases with a decrease in temperature.
B)decreases with an increase in temperature.
C)increases with an increase in temperature.
D)increases with an increase in pressure.

Question 24

Which of the following is a good explanation for why dew tends to form in the grass at night?

A)Temperatures are coolest in the grass.
B)The atmosphere cannot form clouds at night.
C)Pressure is greatest then.
D)More water vapor is present at night.

Question 25

An adiabatic process is one in which the:

A)temperature remains constant.
B)altitude of the air parcel remains constant.
C)heat exchanged with the surroundings is zero.
D)pressure on the air parcel remains constant.
E)work done is zero.

Question 26

During the process of adiabatic cooling,the temperature decreases because the air has:

A)been compressed.
B)lost heat to the colder air at higher altitudes.
C)lost some of its water vapor.
D)expanded to a larger volume.
E)emitted infrared radiation.

Question 27

If the air temperature remains constant,evaporating water into the air will ________ the dew point and ________ the relative humidity.

A)increase,decrease
B)not change,increase
C)decrease,increase
D)decrease,decrease
E)increase,increase

Question 28

Assume that the actual vapor content of the air remains constant over the course of a day.How does the relative humidity at 2:00 p.m.probably compare to the relative humidity at 5:00 a.m.?

A)The relative humidity at 2:00 p.m.is higher.
B)The relative humidity at 2:00 p.m.is lower.
C)The relative humidity is the same at 2:00 p.m.as at 5:00 a.m.

Question 29

When the dry and wet bulb temperatures measured by a psychrometer are equal,all but one of the following is true.Which one is false?

A)A rise in temperature would cause condensation.
B)The air is saturated.
C)Water vapor content is at a maximum.
D)Relative humidity is 100 percent.

Question 30

The buoyancy of a rising air parcel is greatly affected by:

A)heat released if water vapor condenses.
B)absorption of solar radiation.
C)air pressure.
D)convergence of the parcel.
E)wind speed.

Question 31

Relative humidity depends on the water vapor present in the air and the:

A)altitude.
B)dew point.
C)latitude.
D)air temperature.
E)pressure.

Question 32

The most important process of cloud formation in the atmosphere is:

A)cooling by release of latent heat of vaporization.
B)cooling by compression of air.
C)radiation cooling.
D)cooling by expansion of air.

Question 33

During a clear,relatively calm day,the relative humidity will tend to ________ from sunrise to early afternoon.

A)decrease
B)remain nearly steady
C)increase

Question 34

Relative humidity indicates the:

A)probability of precipitation.
B)chance of cloud formation.
C)chance for evaporation of water.
D)nearness to saturation for the air.
E)actual amount of water in the air.

Question 35

As the temperature of air is reduced to its dew point,which of these is most likely to occur?

A)freezing
B)condensation
C)melting
D)supercooling
E)evaporation

Question 36

A wet-bulb thermometer and a dry-bulb thermometer are both parts of which meteorological instrument?

A)an anemometer
B)a thermistor
C)a sling psychrometer
D)a barometer

Question 37

The temperature of rising air parcels ________ as they move upward.

A)decreases
B)increases
C)remains constant
D)may either increase or decrease

Question 38

Adiabatic processes are only important for air:

A)masses which remain near the earth's surface.
B)that is saturated.
C)that is polluted.
D)that is stagnant.
E)which is rising or sinking.

Question 39

In order to have significant snowfall accumulation,dew points must generally be above:

A)0°F.
B)-10°F.
C)10°F.
D)32°F.

Question 40

The property which primarily controls how much water can be present as a gas is:

A)number of particulates present.
B)availability of latent heat.
C)temperature of the air.
D)water's specific heat.
E)amount of dry air gases present.

Question 41

The atmosphere is most unstable when the temperature of the air ________ with height.

A)is uniform
B)drops rapidly
C)increases slightly
D)decreases slightly
E)increases rapidly

Question 42

Which type of lifting mechanism results from warm air lifting over cold air?

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

Question 43

Why does a rising air parcel cool off?

A)Its relative humidity is less than 100 percent.
B)It loses heat to its surroundings.
C)It loses energy by radiation.
D)It expands.
E)It is unstable.

Question 44

The moist adiabatic rate is different from the dry adiabatic rate because:

A)an unstable air parcel expands more rapidly.
B)latent heat is released inside a parcel of rising saturated air.
C)saturated air is always unstable.
D)a parcel of saturated air weighs less than a parcel of unsaturated air.
E)unsaturated air is always stable.

Question 45

An inversion represents an extremely stable atmosphere because a parcel of air that rises into an inversion will eventually become ________ and ________ dense than the air surrounding it.

A)colder,less
B)colder,more
C)warmer,less
D)warmer,more

Question 46

If your environmental lapse rate is 17 C/km on a partly cloudy afternoon,then the atmosphere is said to be:

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

Question 47

An increase in the environmental lapse rate of an air layer results in the layer becoming:

A)less stable.
B)an air parcel.
C)cooler.
D)more stable.
E)heavier.

Question 48

These two conditions,working together,will make the atmosphere the most unstable.

A)warm the surface and warm the air aloft
B)warm the surface and cool the air aloft
C)cool the surface and warm the air aloft
D)cool the surface and cool the air aloft

Question 49

All of the following are lifting mechanisms in the atmosphere EXCEPT:

A)Orographic
B)Divergence
C)Convection
D)Frontal wedging

Question 50

Which of these pairs of processes,working together,will make the atmosphere most unstable?

A)cool the surface and cool the air aloft
B)cool the surface and warm the air aloft
C)warm the surface and warm the air aloft
D)warm the surface and cool the air aloft

Question 51

A large negative temperature lapse rate would occur in a layer with:

A)uniformly cold temperatures throughout.
B)cold air above,warm air below.
C)warm air above,cold air below.
D)uniformly warm temperatures throughout.

Question 52

The change in the actual air temperature as you go up into the atmosphere is called:

A)environmental lapse rate.
B)convergence.
C)latent heat.
D)conversion.
E)diffusion.

Question 53

A stable atmosphere is one in which:

A)clouds are forming.
B)upward vertical motions are resisted.
C)rising bubbles of air accelerate upward.
D)temperatures are adiabatic.

Question 54

The vertical motions that occur when the air is unstable are termed:

A)convection.
B)subsidence.
C)cyclonic.
D)geostrophic.
E)convergence.

Question 55

Natural convection and turbulence are most likely to occur when:

A)temperature decreases rapidly with height.
B)relative humidity is low.
C)temperature increases with height.
D)air pressure is relatively high.
E)wind is nearly calm.

Question 56

The stability of an air layer refers to its:

A)tendency to either sustain or suppress upward vertical motions.
B)albedo.
C)overall density.
D)pressure as measured at its base.

Question 57

A convergence of winds near the surface is associated with cloud production because it:

A)increases the lapse rate.
B)creates a vortex or spiral pattern.
C)increases the wind speed.
D)increases the dew point.
E)forces the air to rise.

Question 58

The environmental lapse rate of an air layer next to the ground is strongly influenced by:

A)barometric pressure.
B)relative humidity.
C)heating or cooling of the ground.
D)adiabatic heating.
E)wind speed.

Question 59

If your environmental lapse rate is 7 C/km on a partly cloudy afternoon,then the atmosphere is said to be:

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

Question 60

An air parcel rises over a mountain and cools adiabatically.Which lifting mechanism has acted on this parcel?

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

Question 61

If the mixing ratio remains unchanged and the temperature drops,the relative humidity will increase.

Question 62

For the following questions,refer to the diagram shown below.

In the diagram shown above,the temperature and dew point at the peak (4000 m)would be: (Assume 100% relative humidity and a wet adiabatic lapse rate of 5°C/km.)

A)both equal to -5°C.
B)both equal to -15°C.
C)equal to -5°C and -10°C,respectively.
D)equal to -15°C and -5°C,respectively.

Question 63

When discussing the water vapor in the air,meteorologists prefer to use absolute humidity rather than mixing ratio.

Question 64

Which of the following would not be associated with stable atmospheric conditions?

A)buildup of pollutants
B)temperature inversion
C)widespread fog
D)afternoon thunderstorms

Question 65

The formation of frost is an example of deposition.

Question 66

For the following questions,refer to the diagram shown below.

In the diagram shown above,the parcel would have a temperature of ________ when it reached the base on the leeward side of the mountain.

A)15°C
B)20°C
C)25°C
D)35°C

Question 67

Sinking or subsiding air cannot form clouds due to the:

A)release of latent heat.
B)loss of particulates.
C)removal of water vapor.
D)formation of unstable layers.
E)warming temperatures.

Question 68

If the temperature remains unchanged and the mixing ratio drops,the relative humidity will increase.

Question 69

More water is evaporated from the oceans than is returned to the oceans by precipitation.

Question 70

Evaporation is a cooling process.

Question 71

Plants release water to the atmosphere through the process of sublimation.

Question 72

A cold air mass that is warmed at its base from contact with the warm ground will have its lapse rate:

A)compressed.
B)decreased.
C)remain constant.
D)increased.
E)changed to an inversion.

Question 73

For the following questions,refer to the diagram shown below.

Given the conditions shown in the diagram above,the elevation of the cloud base would be:

A)111000 m
B)2000 m
C)2500 m
D)3000 m

Question 74

If air at sea level with a temperature of 27°C is forced up a mountain slope and the air's dew point at the condensation level is 14°C,at what elevation will condensation begin?

A)2700 meters
B)1300 meters
C)1400 meters
D)2600 meters

Question 75

The average annual precipitation for the earth is equal to the annual amount of evaporated water.

Question 76

Which of the following will not cause air to become more unstable?

A)forceful lifting of air
B)subsidence of an air column
C)intense solar heating which warms the air from below
D)upward movement caused by general convergence

Question 77

It takes 1 calorie to raise 1 gram of water 1°C.

Question 78

Both absolute humidity and relative humidity change if the temperature of the air changes.

Question 79

If the environmental lapse rate is less than the wet adiabatic lapse rate,then the atmosphere is:

A)absolutely stable.
B)absolutely unstable
C)conditionally unstable
D)cannot determine from this information.

Question 80

The stability of the air layer close to the earth's surface can vary markedly.Much of this variation is caused by:

A)changes in wind speed.
B)changes in pressure.
C)changes in wind direction.
D)changes in heating or cooling of the surface.