Deck 9: Wind: Small Scale and Local Systems

Question 1

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)2
B)4
C)5
D)25

Answer 1

B

Question 2

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.

Answer 2

A

Question 3

Dust storms and dust devils are ____ on Mars.

A) infrequent
B) extremely rare
C) common

Answer 3

C

Question 4

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.

Question 5

The howling of wind on a blustery night is believed to be caused by

A) variation in air temperature.
B) wind blowing around a frozen surface.
C) snowflakes striking one another but not sticking together.
D) eddies of higher air density.
E) wind lifting,then lowering small objects at the surface.

Question 6

Which below has the least influence on determining how high a wind wave will grow over the open ocean?

A) fetch of water
B) density of water
C) length of time the wind blows over the water
D) wind speed over the water

Question 7

Which below is not true concerning an "air pocket"?

A) can form in a downdraft of an eddy
B) often form in the atmosphere where the air is too thin to support the wings of an airplane
C) often form in regions that exhibit strong vertical wind shear
D) can develop in clear air

Question 8

The size and shape of a turbulent eddy depend on

A) the size of the obstacle.
B) the shape of the obstacle.
C) the speed of the wind.
D) all of the above
E) only size and shape of the obstacle.

Question 9

Which of the features below could indicate prevailing wind direction?

A) sand ripples
B) sand dunes
C) "flag" trees
D) all of the above

Question 10

On a clear,windy day,the depth to which mixing occurs above the surface depends upon

A) the wind speed.
B) surface heating.
C) the landscape.
D) all of the above

Question 11

An example of microscale motion is

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 12

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.

Question 13

Which of the following associations is most accurate?

A) microscale - chinook wind
B) synoptic scale - sea breeze
C) mesoscale - land breeze
D) planetary scale - lake breeze

Question 14

The wind's speed generally increases with height above the earth's surface because

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

Question 15

Thermal turbulence above the surface is usually most severe

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

Question 16

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.

Question 17

Clear Air Turbulence (CAT)can occur

A) near a jet stream.
B) in areas of mountain waves.
C) where strong wind shear exists.
D) all of the above

Question 18

An example of mesoscale motion is

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 19

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

Question 20

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 21

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.

Question 22

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 23

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 24

A katabatic wind is a ____ and ____ wind.

A) cold,upslope
B) warm,upslope
C) cold,downslope
D) warm,downslope

Question 25

The nighttime counterpart of the sea breeze circulation is called a

A) chinook.
B) Santa Ana.
C) land breeze.
D) night breeze.
E) foehn.

Question 26

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 27

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) diverging and sinking.
D) diverging and rising.

Question 28

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 29

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.

Question 30

Which is not a characteristic of a thermal low?

A) forms in a region of warm air
B) forms in response to variations in surface air temperature
C) becomes stronger with increasing height
D) lowest pressure is at the center

Question 31

A wind reported as 45 would be a wind blowing from the:

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

Question 32

A valley breeze would develop its maximum strength

A) at sunrise.
B) in early afternoon.
C) about an hour after sunset.
D) about midnight.

Question 33

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.

Question 34

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 35

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 36

Low pressure becomes best developed over the Asian continent in

A) summer.
B) winter.
C) fall.
D) spring.

Question 37

An offshore wind

A) blows from land to water.
B) blows from water to land.
C) blows only at night.
D) only blows during the day.

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.

Question 39

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

A) east,west
B) west,east
C) west,west
D) east,east

Question 40

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.

Question 41

A northeaster along the east coast of the United States is best developed when a low pressure area

A) moves from west to east over Canada.
B) moves eastward over the Great Lakes.
C) moves northward over Ohio.
D) moves northeastward from the Texas panhandle.
E) moves northeastward over the Atlantic Ocean adjacent to the coast.

Question 42

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

A) away from the shore,pressure gradients are large.
B) away from the shore,pressure gradients are small.
C) it is raining.
D) it is foggy.

Question 43

What is clear air turbulence (CAT)? Why does clear air turbulence represent a hazard to aviation?

Question 44

Summertime weather forecasts for cities on the shores of the Great Lakes often contain the phrase "cooler near the lake".Explain the relevance of this phrase.

Question 45

You are hiking on a mountain trail at sunrise when you smell the smoke from cooking bacon.You can't see where the smoke is coming from.Would you expect the camp to be above you or below you on the mountain? Explain.

Question 46

Draw a sketch to show where eddies can form when air blows rapidly over a mountain range.Show on your sketch where you might expect clouds to form.How would these clouds appear when viewed from the ground?

Question 47

Strong winds blowing over vegetation results in

A) physically damaged plants.
B) decreased crop productivity.
C) rapid water loss.
D) all of the above

Question 48

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 49

List the scales of atmospheric motion from largest to smallest and give an example of each.From what you know about the various types of wind systems,are the size and duration related?

Question 50

Good hang-gliding conditions require

A) thermal turbulence.
B) upward air motions.
C) molecular viscosity.

Question 51

What is meant by the term monsoon wind system? Briefly describe or sketch the wind and pressure pattern during the summer and winter monsoon in Asia.

Question 52

Which of the following is a serious hazard to aircraft?

A) molecular viscosity
B) laminar flow
C) clear-air turbulence
D) longwaves in the westerlies
E) none of the above

Question 53

Briefly sketch or describe the formation of a chinook wind.Would you expect chinook winds to form more often on the eastern or the western slopes of the Cascade Mountains in Oregon?

Question 54

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

A) thermal circulations.
B) mechanical circulations.
C) atmospheric longwave circulations.

Question 55

How might knowledge of the direction of the prevailing wind at a given location be used in landscape design or the design of an energy efficient home?

Question 56

Which of the following conditions favor the development of dust devils?

A) hot,moist days
B) hot,dry days
C) cold,moist days
D) cold,dry days

Question 57

Briefly sketch or describe the conditions that lead to the formation of a Santa Ana wind.Is the Santa Ana wind dry or moist,warm or cold?

Question 58

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

A) expansion
B) compression
C) evaporation
D) both expansion and evaporation

Question 59

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 60

Would you expect a well-developed sea breeze circulation to cause clouds to form over the land or over the ocean?

Question 61

Will a valley breeze or a mountain breeze produce clouds? Explain.

Question 62

Explain how Florida's sea breezes can increase the potential for wildfires.

Question 63

When air flows over a mountain range,why do clouds tend to form on the upwind rather than on the downwind side of the range?

Question 64

How can winds be observed by satellites?

Question 65

Areas along the shores of the Great Lakes often experience a lake breeze circulation.Are these winds different than those associated with a sea breeze circulation? Explain.