Deck 9: Wind: Small-Scale and Local Systems

Question 1

What is an example of microscale motion?

A)Winds on a surface weather map of North America
B)Winds on a 500 mb chart
C)Winds blowing through a city
D)Winds blowing past a chimney
E)Average wind patterns around the world

Answer 1

D

Question 2

Compressional heating is the main source of warmth for a Chinook wind.

Answer 2

True

Question 3

Wind direction and speed can be determined with an aerovane.

Answer 3

True

Question 4

Strong winds blowing over vegetation results in rapid water loss in the plant.

Question 5

What is an example of mesoscale motion?

A)Winds on a surface weather map of North America
B)Winds on a 500 mb chart
C)Winds blowing through a city
D)Winds blowing past a chimney
E)Average wind patterns around the world

Question 6

Sand ripples can indicate the prevailing wind direction in an area.

Question 7

Microscale circulations range from a few kilometers to about a hundred kilometers in diameter.

Question 8

Clear air turbulence often occurs near a boundary of high wind shear.

Question 9

Thermal lows form in response to variations in surface air temperature.

Question 10

In city planning, sewage disposal plants must be situated upwind from large housing developments.

Question 11

The airflow on a sand dune is strongest at the top of the dune.

Question 12

Which association is most accurate?

A)Microscale - chinook wind
B)Synoptic scale - sea breeze
C)Mesoscale - land breeze
D)Planetary scale - lake breeze
E)Universal scale - ocean breeze

Question 13

In the northeastern half of the United States, the prevailing wind in winter is southwest and in summer it is northwest.

Question 14

The difference in surface wind speed between morning and afternoon is typically greater on a clear, sunny day than on a cloudy, overcast day.

Question 15

Thermal lows become weaker with increasing height.

Question 16

Friction is not restricted to solid objects; it occurs in moving fluids as well.

Question 17

Prevailing offshore winds in summer carry moisture, cool air, and fog into coastal regions, whereas prevailing onshore breezes carry warmer and drier air into the same locations.

Question 18

A valley breeze develops its maximum strength in the early afternoon.

Question 19

The amount of energy transferred to the water (and thus the height to which a wave can build)depends upon four factors:
1. wind speed
2. length of time that the wind blows over the water
3. the fetch
4. wind direction.

Question 20

Coastal areas can have heavy waves on a clear, nonstormy day.

Question 21

The most practical location for building a wind turbine would be ____.

A)in a region of strong, gusty winds
B)on the downwind side of a mountain
C)in a narrow valley
D)in a region of moderate, steady winds
E)anywhere on top of a mountain

Question 22

The wind's speed generally increases with height above Earth's surface because ____.

A)only the lowest layer of air rotates with Earth
B)air temperature normally decreases with height
C)wind instruments are not accurate at Earth's surface
D)friction with Earth's surface slows the air near the ground
E)air parcels expand and become less dense as they rise above the surface

Question 23

The nighttime counterpart of the sea breeze circulation is called ____.

A)Chinook
B)Santa Ana
C)land breeze
D)a night breeze
E)foehn

Question 24

A sea breeze circulation will reverse direction and become a land breeze ____.

A)once every few days
B)at the beginning and the end of the summer
C)several times per day
D)once per day
E)once a month

Question 25

A wind reported as 225 degrees would be a wind blowing from the ____.

A)NE
B)S
C)SW
D)NW
E)E

Question 26

A sea or land breeze is caused by ____.

A)differences in humidity
B)temperature differences
C)the Coriolis force
D)ocean tides
E)strong surf conditions

Question 27

If huge waves pound against the beach communities of Southern California for several days during clear, calm weather, it is a good bet that ____.

A)the winds are strong somewhere out over the Pacific Ocean
B)an earthquake has occurred somewhere on the ocean floor
C)it is raining offshore
D)it is a period of high tides
E)there is a large difference in water density between the shoreline of Southern California and the middle of the Pacific

Question 28

Surface winds are generally strongest and most gusty ____.

A)in the afternoon
B)in the early morning
C)around midnight
D)just after sunset
E)just before sunrise

Question 29

Suppose the wind speed increased from 5 mph to 10 mph. We can conclude that the force exerted by the wind increased by a factor of ____.

A)0.5
B)2
C)4
D)5
E)25

Question 30

Thermal turbulence above the surface is normally at a minimum during the ____.

A)early morning
B)middle of the day
C)early evening
D)late evening
E)middle of the night

Question 31

The leveche (a hot, dry wind experienced in southeast Spain)originates from a low-pressure area centered immediately north of ____.

A)Tunisia
B)Morocco
C)Algeria
D)Libya
E)Portugal

Question 32

The size and shape of a turbulent eddy depends upon ____.

A)the composition of the obstacle
B)the size and shape of the obstacle
C)the wind direction
D)topography of the surrounding landscape
E)elevation where the obstacle is located

Question 33

An offshore wind blows ____.

A)from land to water
B)from water to land
C)only at night
D)only during the day
E)a minimum distance of 100 miles away from the shore

Question 34

A wind rose indicates ____.

A)the wind speed at a location at a particular time
B)the percentage of time that the wind blows from different directions
C)observed wind speed and direction on a surface map
D)spinning wind patterns caused by buildings or other obstructions
E)a rose fossilized by wind

Question 35

Which of the below determines how high a wind wave will grow over the open ocean?

A)Water quality
B)Density of water
C)Length of time the wind blows over the water
D)Shoreline topography
E)Geographical location

Question 36

The slowing of the wind due to the random motion of air molecules is called ____.

A)eddy viscosity
B)mechanical turbulence
C)molecular viscosity
D)convective turbulence
E)kinetic viscosity

Question 37

Thermal turbulence above the surface is usually most severe ____.

A)immediately after sunset
B)during maximum surface heating
C)around midnight
D)just before sunrise
E)about midmorning, or soon after the minimum temperature is reached

Question 38

During the summer in humid climates, nighttime clouds tend to form over water during a ____.

A)land breeze
B)chinook wind
C)sea breeze
D)Santa Ana wind
E)lake breeze

Question 39

Suppose a west wind of 20 knots blows over a coastal region which is densely covered in shrubs. If this same wind moves out over the middle of a large calm lake, its speed and direction would probably be ____.

A)greater than 20 knots and more northwesterly
B)less than 20 knots and more northwesterly
C)greater than 20 knots and more southwesterly
D)less than 20 knots and more southwesterly
E)less than 20 knots and westerly

Question 40

The top of the planetary (atmospheric)boundary layer is usually near ____.

A)10 m
B)100 m
C)500 m
D)1,000 m
E)10,000 m

Question 41

Clouds and precipitation are frequently found on the downwind side of a large lake. This would indicate that the air on the downwind side is ____.

A)converging and rising
B)converging and sinking
C)stable and rising
D)diverging and sinking
E)diverging and rising

Question 42

Cumulus clouds that appear above isolated mountain peaks are often the result of ____.

A)katabatic winds
B)mountain winds
C)fall winds
D)Santa Ana winds
E)valley breezes

Question 43

In south Florida the prevailing winds are ____. Because of this, the strongest sea breeze is usually observed on Florida's east coast, and the ____ land breeze on Florida's west coast.

A)northeasterly; strongest
B)northeasterly; weakest
C)northwesterly; strongest
D)northwesterly, weakest
E)easterly; weakest

Question 44

Chinook winds are ____.

A)warm, dry downslope winds
B)warm, moist downslope winds
C)cold, dry downslope winds
D)cold, moist downslope winds
E)warm, dry upslope winds

Question 45

On the eastern side of the Rocky Mountains, chinook winds are driest when ____.

A)clouds form and precipitation falls on the upwind side of the mountains
B)the air aloft is cold
C)the Sun is shining
D)the winds are blowing from the east
E)surface friction is greatest on the downwind side of the mountain

Question 46

An upper wind direction is reported as 135°. From what compass direction is the wind blowing?

A)North
B)South
C)Northeast
D)Southeast
E)Northwest

Question 47

Wind gusts are caused by ____.

A)turbulent eddies
B)wind waves
C)mesoscale circulations
D)wind shear
E)circulations on the synoptic scale

Question 48

A sea breeze is most likely to develop along a coastline when ____.

A)pressure gradients between the land and sea are large
B)pressure gradients between the land and sea are small
C)it is raining
D)it is foggy
E)surface temperatures are high

Question 49

Dust devils ____.

A)generally form on clear, hot, dry days
B)always have a spin around the central core that is cyclonic
C)always have a spin around the central core that is anticyclonic
D)are long-lasting
E)tend to have heights greater than 100 m (300 feet)

Question 50

While fly fishing in a mountain stream, you notice that the wind is blowing upstream. From this, you could deduce that the wind is a ____.

A)chinook wind
B)valley breeze
C)Santa Ana wind
D)mountain breeze
E)katabatic wind

Question 51

The land/sea breeze, lake breeze, and mountain/valley breeze are examples of ____.

A)thermal circulations
B)mechanical circulations
C)atmospheric longwave circulations
D)thermal turbulences
E)frictional processes

Question 52

Thermally generated eddies typically peak ____.

A)at sunrise
B)around midnight
C)at sunset
D)at noon
E)in the afternoon

Question 53

When a sea breeze moving north meets a sea breeze moving south, they form a ____.

A)land breeze
B)sea breeze convergence zone
C)katabatic wind
D)valley breeze
E)thermal low

Question 54

What is a serious hazard to aircraft?

A)Molecular viscosity
B)Laminar flow
C)Clear-air turbulence
D)Longwaves in the westerlies
E)Thermal lows

Question 55

The heat from a chinook wind is generated mainly by ____.

A)compressional heating
B)sunlight
C)warm, ocean water
D)friction with the ground
E)forest fires

Question 56

The summer monsoon in eastern and southern Asia is characterized by ____.

A)wet weather and winds blowing from land to sea
B)dry weather and winds blowing from land to sea
C)wet weather and winds blowing from sea to land
D)dry weather and winds blowing from sea to land
E)continual rain and winds blowing from all directions

Question 57

The winter monsoon in eastern and southern Asia is characterized by ____.

A)wet weather and winds blowing from land to sea
B)wet weather and winds blowing from sea to land
C)dry weather and winds blowing from sea to land
D)dry weather and winds blowing from land to sea
E)dry weather and Chinook winds

Question 58

An ideal setting for a katabatic wind is ____.

A)a valley that is near a large river
B)a canyon that flows into the sea
C)a large elevated lake with a forest nearby
D)an area where the land and the shore meet
E)an elevated plateau surrounded by mountains with a nearby downhill slope

Question 59

During the summer along the coast, a sea breeze is usually strongest and best developed ____.

A)in the afternoon
B)just after sunrise
C)just before sunset
D)just before noon
E)around midnight

Question 60

The synoptic scale describes circulations on the ____ scale.

A)micro
B)global
C)meso
D)macro
E)weather-map

Question 61

An aerovane is an instrument that indicates both wind ____________________ and ____________________. It consists of a bladed propeller that rotates at a rate proportional to the wind speed. Its streamlined shape and a vertical fin keep the blades facing into the wind. When attached to a recorder, a continuous record of both wind speed and direction is obtained.

Question 62

Turbulent eddies can occur in conjunction with mountain waves, which may extend upward into the stratosphere. When these huge eddies develop in clear air, this form of turbulence is referred to as ____.

Question 63

The macroscale combines the ____________________ and ____________________ scales.

Question 64

When wind encounters a solid object, a whirl of air, called an eddy, forms on the object's ____________________ side.

Question 65

When the slowing of a fluid-such as air-is due to the random motion of the gas molecules, the viscosity is referred to as ____________________.

Question 66

Stationary storm systems, centered somewhere over the open sea, are capable of creating large waves with wave heights measuring over ____.

A)11 m (36 feet)
B)21 m (69 feet)
C)31 m (100 feet)
D)41 m (134 feet)
E)51 m (167 feet)

Question 67

Eddies that form both close to the mountain and beneath each wave crest are called ____.

A)mountain wave eddies
B)wind shear
C)clear air turbulence
D)leeward eddies
E)rotors

Question 68

The friction of fluid flow is called ____________________.

Question 69

The force of the wind on an object is ____________________ to the wind speed squared.

Question 70

When wind blows over a snow field, and if the wind is sufficiently strong, the moving clumps of snow become cylindrical, often with a hole extending through them lengthwise. These snow ____ range from the size of eggs to that of small barrels.

A)rollers
B)waves
C)ripples
D)dunes
E)dunes

Question 71

If you are standing directly south of a smoke stack and the wind from the stack is blowing over your head, what would be the wind direction?

A)North
B)East
C)South
D)West
E)Northeast

Question 72

To protect crops and soil from wind-related erosion, shelterbelts, more formally known as ____, are planted.

Question 73

A pilot enters the weather service office and wants to know what time of the day she can expect to encounter the least turbulent winds at 760 m (2,500 feet)above central Kansas. If you were the weather forecaster, what would you tell her?

A)At midnight
B)In the early morning
C)At noon
D)In the afternoon
E)At sunset

Question 74

A katabatic wind is a cold and ____________________ wind.

Question 75

Mesoscale circulations have a(n)____________________ (longer/shorter)duration than microscale circulations.

Question 76

When sustained winds or frequent gusts reach 35 miles/hour, the blowing or falling snow can produce ____________________ conditions.

Question 77

Waves forming by wind blowing over the surface of the water are known as ____.

A)ripples
B)waves
C)wind waves
D)fetch
E)surf

Question 78

Santa Ana winds warm by ____________________ as they flow down an elevated desert plateau.

Question 79

Wind blowing with sufficient force to move an automobile ____.

A)is common
B)is impossible
C)is uncommon
D)generally only happens during a hurricane or tornado
E)generally only occurs at high elevations

Question 80

Blowing sand eventually comes to rest ____________________ obstacles, which can be anything from a rock to a clump of vegetation.