MET Flashcards
(209 cards)
1
Q
The part of the earth’s atmosphere where most of the clouds and precipitation are found is:
A
A) The insulation zone
B) The mesosphere
C) The troposphere
D) The terrestrial radiation zone
C
2
Q
Pick the false statement with respect to the tropopause.
A
A) The tropopause is lower over the poles.
B) The tropopause is higher over the equator.
C) The temperature at the tropopause is colder over the poles.
D) The temperature at the tropopause is warmer over the poles.
C
3
Q
Is the height of the tropopause higher over the poles or equator?
A
A) Poles - the density of the air in this region is greater and therefore higher
B) Equator - the density of the in this region is greater and therefore higher
C) Poles - the density of this air in the region is less and therefore higher.
D) Equator - the density of the air in this region is less and therefore lighter.
D
4
Q
The height of the tropopause will tend to be higher in:
A
A) In a warmer air mass.
B) When the MSL pressure is high.
C) At a lower level in a warmer air mass.
D) Both (a) and (b) are correct
D
5
Q
That region of the atmosphere between the stratopause and the mesopause is known as:
A
A) The exosphere
B) The thermosphere
C) The ionosphere
D) The mesosphere
D
6
Q
The sun emits large amounts of ultraviolet radiation and is largely absorbed by a colourless gas that is found at varying amounts throughout the atmosphere. This gas is known as:
A
A) Carbon monoxide
B) Nitrogen pentoxide
C) Ozone
D) Methane
C
7
Q
The earth’s surface is heated by:
A
A) Short wave solar (ultraviolet) radiation
B) Kinetic activity in the lower troposphere
C) Long wave solar (infrared) radiation
D) Conduction
A
8
Q
What is the Intertropical Convergence Zone (ITCZ)?
A
A) It is the area on the earth where solar radiation is at its weakest
B) It is the area on the earth where solar radiation is at its strongest
C) It is where two highs converge together
D) It is where two lows converge together
B
9
Q
Why does the ITCZ move south during the winter months?
A
A) The relationship between the earth, the sun and the moon slightly shifts earth’s orbit causing the maximum solar radiation to shift south (Jesus H Christ)
B) Where the cold air and warm air meet shifts the ITCZ southwards during the winter months
C) The Northern Hemisphere tilts towards the sun during winter forcing the cold air southwards along with the ITCZ
D) The Northern Hemisphere becomes tilted away from the sun during winter meaning the point of maximum solar radiation striking the earth moves southward.
D
10
Q
The lower atmosphere is heated by:
A
A) Short wave solar (ultra violet) radiation.
B) Conduction
C) Long wave solar (infrared) radiation.
D) Both b and c are correct.
D
11
Q
Temperatures in the lower stratosphere approximate those:
A
A) That exist at the 300 hPa pressure surface.
B) Of the stratosphere
C) That are observed a the midpoint of the earth’s laminar boundary layer.
D) Of the tropopause.
D
12
Q
In the International Standard Atmosphere (ISA) the temperature at Sea Level is 15degC and the pressure at the level is 1013.2 hPa. What would the ISA temp be for FL300?
A
A) -75degC
B) -45degC
C) -60degC
D) -56.5degC
B
13
Q
The actual temperature at FL280 IS -48C. How would this temperature be expressed in terms of an ISA deviation?
A
A) ISA -10C
B) ISA +7C
C) ISA -7C
D) ISA +8C
C
14
Q
If you are flying at 34,000’ with a SAT of -50C and the tropopause was actually at 30,000’ where SAT was -45C, what is the deviation from ISA?
A
A) ISA -3C
B) ISA +3C
C) ISA +5C
D) ISA -5C
B
15
Q
As air moves horizontally over the earth in the N Hemisphere, the air is deflected to the right. This is known as the Coriolanus and it is caused by the :
A
A) Rotation of the earth
B) Vorticity in the lower atmosphere
C) Mesoscale gravity waves
D) Geostrophic acceleration
A
16
Q
Which of the following statements with respect to Coriolis is correct?
A
A) Coriolis is stronger closer to the equator
B) Coriolis is weaker at the higher latitudes
C) Coriolis is stronger nearer to the poles
D) Coriolis does not change with change in latitude
C
17
Q
Vertical air currents are often created within the atmosphere by varying means. A process that will lead to rising air is known as:
A
A) Advection
B) Convection
C) Dispersion
D) Convergence
D
18
Q
Which of the following would experience the LEAST diurnal range in temperature?
A
A) Tropical rain forest
B) Temperate zone oceans
C) Desert
D) Mountain valleys
B
19
Q
Which of the following statements is false
A
A) Deserts and open fields on the Earth’s surface heat up and cool down relatively easy promoting rising air during the nighttime
B) Lakes and oceans will promote convection and rising air
C) Convection is more likely to occur over water-free surfaces
D) a and b are false
D
20
Q
The lifting process responsible for the choppy type of turbulence often encountered during flight within the lower 3000’ of the troposphere is:
A
A) Orographic lift
B) Convergence
C) Mechanical turbulence
D) Advection cooling
C
21
Q
Which of the following is NOT a lifting agent?
A
A) Evaporation
B) Convection
C) Mechanical turbulence
D) Convergence
A
22
Q
Meteorologists use the term convergence to depict air that is:
A
A) Flowing along the earth’s surface from areas of higher pressure into and converging at an area of lower pressure.
B) Lifting orographically.
C) Spreading out from an area.
D) Becoming conditionally stable.
A
23
Q
Which of the following processes can result in expansional cooling, subsequent condensation and formation of cloud?
A
A) Subsidence
B) Divergence
C) Frontolysis
D) Overrunning
D
24
Q
Define “overrunning”
A
A) It refers to how fast the cold air rises vertically as it flows up along the frontal surface over the retreating warm air.
B) It is a term used to describe how fast the warm front is moving.
C) It is a term used to describe how fast the cold front is moving.
D) It refers to how fast warm air rises vertically as it flows up along the frontal surface over the retreating cold air.
D
25
The clouds and precipitation often associated wth a cyclone are due to:
A) The presence of strong winds and associated mechanical turbulence.
B) The associated cold outflow leads to a steep lapse rate and instability.
C) Surface convergence and ascending air.
D) Advectional heating of moist air that inflows across the surface isobars.
C
26
Which of the following would be used to describe the process whereby a rising, expanding parcel of air does not undergo any heat transfer in or out of the parcel as it ascends?
A) Osmotic
B) Diabatic
C) Isentropic
D) Adiabatic
D
27
Subsiding air, even if it’s initially saturated, will:
A) Continue to warm at the saturated adiabatic lapse rate
B) Warm at the dry adiabatic lapse rate
C) Warm at the environmental lapse rate
D) Increase in temperature at the ISA lapse rate
B
28
With respect to air that is descending rapidly down the lee slopes of a mountain range, which of the following statements is true?
A) Considerable cloud will be found near the end of its descent
B) This air will warm at the dry adiabatic lapse rate almost immediately after the start of it’s descent
C) The relative humidity of this air increases rapidly during its descent
D) Warming of this air will be at the saturated adiabatic lapse rate during most of its descent
B
29
When air subsides, normally the:
A) Pressure gradient steepens
B) Moisture content increases
C) Temperature decreases
D) Relative humidity decreases
D
30
When air ascends, its ability to contain moisture:
A) Increases
B) Remains unchanged
C) Initially increases, then decreases
D) Decreases
D
31
During the condensation process which of the following is true?
A) The relative humidity of the surrounding air decreases
B) Latent heat is released to the surrounding air
C) Latent heat is absorbed from the surrounding air
D) The condenses water vapour molecules will enter a higher energy state
B
32
When condensation occurs in an unstable air mass, the stability of the air tends to become:
A) More unstable as heat is released to the surrounding air
B) More stable as heat is released to the surrounding air
C) More unstable as the surrounding air is cooled from absorption of latent heat
D) More stable as the surrounding air is cooled from absorption of latent heat
A
33
With a surface temp of 28C and a dew point of temp of 16C reported at your airport, you would predict the base of any connective cloud that might form to be approximately:
A) 7600’ AGL
B) 6400’ AGL
C) 4900’ AGL
D) 2900’ AGL
C
34
With respect to a rising parcel of air which commences to ascend from a seal level airport where the temperature is 30C, what would be it’s temperature at 14, 000’ above sea level if it became saturated at 6, 000’ above sea level?
A) +2C
B) +0C
C) -1C
D) +6C
B
35
When discussing the stability/instability of the atmosphere, we are referring to:
A) The diurnal fluctuations in the height of pressure surfaces aloft
B) A property of the atmosphere that suppresses or promotes vertical motion
C) The varying speeds and slopes of frontal surfaces and their effect on the surface temperature field
D) The effects of macro-scale temperature distribution in the upper troposphere
B
36
The stability of warm, dry air depends on the relationship between the:
A) Saturated adiabatic lapse rate and the dry adiabatic lapse rate
B) Dry adiabatic lapse rate and the standard lapse rate
C) Dry adiabatic lapse rate and the environmental lapse rate
D) Saturated adiabatic lapse rate and the environmental lapse rate
C
37
Stable air is most likely to be associated with:
A) Cold air advecting over a warm surface
B) Showery precipitation
C) Gusty winds
D) Sustained low visibility
D
38
Haze layers, drizzle and fog are features of:
A) Overrunning air
B) Stable air
C) A convergence zone
D) Advectional heating of cold air
B
39
Stable air becomes unstable as a result of:
A) Subsidence
B) Radiational cooling
C) Addition of moisture
D) Heating from below
D
40
A good signpost of mid-level instability would be the presence of:
A) Stratocumulus
B) Cirrocumulus
C) Altocumulus Castellanus
D) Cumulus Fractus
C
41
Which of the following effectively inhibits or blocks rising air?
A) A frontal depression
B) A supercooled layer aloft
C) An inversion
D) A convergence zone
C
42
The pilot of an aircraft would expect the smoothest low level flight during a hot summer afternoon when passing over which of the following surface features?
A) A forest
B) A plowed field
C) A lake
D) A vineyard
C
43
A pressure of 200 hPa is closest to which of the following levels in the ICAO standard atmosphere?
A) FL600
B) FL450
C) FL390
D) FL340
C
44
FL450 is associated with which pressure level in the ICAO Standard Atmosphere?
A) 250 hPa
B) 150 hPa
C) 200 hPa
D) 300 hPa
B
45
The vertical distance between any two specific pressure levels is:
A) Greater in cold air than in warm air
B) Not affected by the temperature of the air
C) Less in cold air than in warm air
D) Solely determined by the adiabatic lapse rate
C
46
The height of a pressure level (ex. 500MB) will tend to be found at:
A) At a higher level in a colder air mass
B) At a higher level when the MSL pressure is low
C) At a lower level in a warmer air mass
D) At a lower level in a colder air mass
D
47
The height of a pressure level will:
A) Become lower when a Low is deepening
B) Become higher when a Low is deepening
C) Become lower when a Low is filling
D) Remain unchanged whether a Low is deepening or filling
A
48
Flying in the lower levels towards the centre of an anticyclone which has a strong pressure gradient, a pilot would expect:
A) High winds and increasing barometric pressure
B) Light winds and relatively constant barometric pressure
C) Clear weather and relatively low barometric pressure
D) High winds and decreasing barometric pressure
A
49
When flying towards a ridge of high pressure at FL200, what happens to the height of the pressure level and your true altitude?
A) Pressure level goes up and your true altitude goes down
B) Pressure level goes up and your true altitude goes up
C) Pressure level goes down and your true altitude goes down
D) Pressure level goes down and your true altitude goes up
B
50
When flying at FL200 towards an area of colder air on the surface of the earth, what happens to the height of the pressure level and your true altitude?
A) Pressure level goes up and your true altitude goes down
B) Pressure level goes up and your true altitude goes up
C) Pressure level goes down and your true altitude goes down
D) Pressure level goes down and your true altitude goes up
C
51
When flying at FL370 towards a ridge of high pressure and an area of warmer air on the surface of the earth, what happens to your indicated altitude (shown on your altimeter) and your true altitude?
A) Indicated altitude goes up, therefore your true altitude goes up
B) Indicated altitude goes down, therefore your true altitude goes up
C) Indicated altitude stays the same, but your true altitude goes down
D) Indicated altitude stays the same, but your true altitude goes up
D
52
An aircraft is parked on the apron. You go home fo the night. During the evening, cold air moves into the vicinity of the airport. When you return to your aircraft in the morning, what does the altimeter show?
A) It will over-read and indicate a higher than normal altitude
B) There will be no change to the altimeters reading
C) It will under-read and indicate a lower than normal altitude
D) It will over-read and indicate a lower than normal altitude
B
53
Which of the following statements relating to an anticyclone is not true?
A) Within this pressure region there is a general increase in relative humidity
B) Fair weather and clear skies normally prevail within the region of an anticyclone
C) An anticyclone is generally characterized by a downward vertical movement
D) Anticyclones can be described as strong or weak and strengthening or weakening
A
54
Surface highs and lows develop as a result of:
A) Converging or diverging air at the surface
B) Strong pressure gradients along the surface
C) Unstable air masses
D) Upper level convergence and divergence forcing air to sink or rise respectively
D
55
A trough is:
A) A wedge-shaped extension of an anticyclone
B) An upper-troposphere contour pattern which is associated with warm air moving towards the North Pole
C) An elongated area of relatively low atmospheric pressure
D) An indefinite isobar configuration located between two highs an two lows
C
56
A neutral area, not bounded by any one isobar, within which light winds are blowing and the weather is changing very slowly, exists between two high and two low pressure systems. The name given to this indefinite pressure area is:
A) A secondary depression
B) A geostrophic divergence zone
C) A surface occlusion
D) A col
D
57
During descent from 3000’ AGL to the surface, you would expect the wind to:
A) Veer and increase
B) Veer and decrease
C) Back and increase
D) Back and decrease
D
58
The wind at 3000’ over the land is parallel to the isobars at 30 its. What would be the most probable angle to the isobars and speed of the surface wind assuming it is not affected by local topography?
A) 0 deg and 20 kts
B) 10 deg and 30 kts
C) 30 deg and 20 kts
D) 40 deg and 40 kts
C
59
Given the same pressure gradient over the land and over the adjacent water, what is the most probable wind angle to the isobars and wind speed over the water if the surface wind over the land is blowing across the isobars at angle of 30 deg and at a speed of 30 kts?
A) 40 deg and 20 kts
B) 30 deg and 30 kts
C) 20 deg and 20 kts
D) 20 deg and 40 kts
D
60
A flight from Vancouver to Montreal at a constant pressure level experiences winds that gradually veer from the southwest to the northwest. The aircraft’s actual height about mean sea level will have: (Hint: port drift - A/C true altitude is increasing; starboard drift - A/C true altitude is decreasing)
A) Increased steadily
B) Increased for a time and then decreased steadily thereafter
C) Decreased steadily
D) Decreased for a time and then increased steadily thereafter
B
61
If the temperature to the southeast today are warmer than those to the northwest, the winds aloft would be blowing from the: (recall Buys-Ballot’s Law - with your back to the wind, your left hand will point to the area of the lower pressure; for upper level winds, your left hand will point to the area of lower temperatures)
A) Northeast
B) Southeast
C) Northwest
D) Southwest
D
62
From the statements listed below which relate to density altitude, select the one which is false:
A) The calculation of the density altitude at a given aerodrome consists of correcting the existing pressure altitude with the ISA temperature for that level.
B) The density altitude is that altitude in the standard atmosphere which corresponds to a given density value.
C) An increase in density altitude corresponds to a decrease in density.
D) The density altitude for a given aerodrome is changing continually in response to changes in pressure and temperature.
A
63
An aerodrome’s density altitude is calculated with a fight computer using the:
A) The aerodrome’s published elevation matched with the ambient air temperature.
B) The aerodrome’s pressure altitude matched with the aerodrome’s outside air temperature corrected in terms of ASL.
C) The aerodrome’s pressure altitude matched with the the aerodrome’s outside air temperature corrected in terms of AGL.
D) The aerodrome altitude above seal level matched with the average sea level temperature during the previous 12 hours.
B
64
An aircraft’s true altitude would be greater than its indicated altitude in conditions of:
A) Warm air and high pressure.
B) Warm air and low pressure.
C) Cold air and high pressure.
D) Cold air and low pressure.
A
65
Which of the following statements is true with respect to the term MSL Pressure?
A) It is a station pressure reduced to MSL assuming ISA conditions.
B) It is a station level pressure extracted from the appropriate synoptic chart.
C) It is a station pressure reduced to MSL using the average surface temperature for the last 12 hours.
D) It is the average sea level pressure reading at a given station during the previous 3 hour period.
C
66
Altimeter setting is:
A) Measured MSL pressure corrected for non-standard temperature.
B) Station pressure reduced to sea level with a 12 hour average temperature correction applied to it.
C) Measured MSL pressure with ISA deviation correction applied.
D) Station level pressure reduced to MSL assuming ISA conditions.
D
67
It is essential that a pilot flying in the Standard Pressure Region closely monitor terrain clearance, when:
A) Pressures are high and temperatures are high.
B) Operating in an air mass having a variable pressure gradient.
C) Pressures are low and temperatures are low.
D) The current altimeter setting is greater than 31.00 inches (Hg).
C
68
An aircraft descends from FL380 for an approach to the Kelowna Airport. During the descent, then pilot forgets to reset the altimeter subscale. If the published decision height (DH) is 2060 feet ASL, what would be the actual height of the aircraft on reaching the indicated DH? (Refer to the following METAR)
METAR CYLW 281700Z 18010KTS 5SM-SHRA OVC015 10/06 A2962 RMK SF8 SLP150=
A) 2060’ ASL
B) 2360’ ASL
C) 1760’ ASL
D) 1460’ ASL
C
69
Compare two aircraft on approach - the 1st aircraft is flying the approach in standard atmospheric conditions; the 2nd aircraft in colder than standard conditions. Both aircraft arrive over the final approach point/fix at the altitude that is shown on the approach plate (no temperature corrections applied). What is the second aircraft’s altimeter reading in relation to the first, and what is the result (Hint: HLHL)?
A) The second aircraft’s altimeter will be over-reading, and therefore the aircraft will be lower than the published altitude.
B) The second aircraft’s altimeter will be under-reading, and therefore the aircraft will be lower than the published altitude.
C) The second aircraft’s altimeter will be under-reading, and therefore the aircraft will be higher than the published altitude.
D) The second aircraft’s altimeter will be over-reading, and therefore the aircraft will be higher than the published altitude.
A
70
Consider that same two aircraft in the question above on a RNAV/RNP style approach. What will happen to the slope of the approach flown by the second aircraft?
A) No difference.
B) The second aircraft will fly a steeper approach path and will touchdown with zero temperature error on the altimeter.
C) The second aircraft will fly a shallower approach path and touchdown with a temperature error the altimeter.
D) The second aircraft will fly a shallower approach path and touchdown with zero temperature error on the altimeter.
D
71
The relationship between the amount of water vapour actually presents in the air and the maximum possible amount of water vapour that could be held by the air at that temperature and pressure (without condensation occurring) is expressed by which of the following terms?
A) Dewpoint temperature.
B) Saturation vapour pressure.
C) Relative humidity.
D) Saturation index.
C
72
The height of a cloud base is most dependent upon the:
A) Moisture content of the air.
B) The dry adiabatic lapse rate.
C) The amount of cooling that is taking place at the earth’s surface.
D) The strength of any vertical motion present at the 400 hPa level.
A
73
Clouds and precipitation are common in areas:
A) Of subsiding air.
B) Located immediately above an isothermal layer.
C) Where katabatic flow is present.
D) Of ascending air.
D
74
Which of the following types of cloud frequently forms as a result of evaporation from rain rather than from expansional cooling?
A) Orographic cloud.
B) Altocumulus castellanus.
C) Cumulus fractas.
D) Stratus cloud.
D
75
If the air mass is moist and stable with mechanical turbulence prevent in the lower levels, what type of clouds can you expect to be present?
A) Stratus cloud.
B) Stratocumulus cloud.
C) Cumulus fractals.
D) Stratus and Stratocumulus cloud.
D
76
Rain droplets or snowflakes that fall from cumuliform could and evaporate or sublimate before reaching the ground is called:
A) Refractive cloud.
B) Curtain cloud.
C) Virgo.
D) Nimbostratus opacus.
C
77
Flying through or underneath virga usually results in:
A) Smooth flying conditions due to the cooling effect as water droplets evaporate back into a gaseous state.
B) Choppy conditions from the condensation process.
C) Choppy flying conditions due to the cooling effect as water droplets evaporate back into a gaseous state causing the more dense air to sink rapidly creating a form of wind shear.
D) Choppy flying conditions through the virga but smooth underneath the virga.
C
78
Drizzle forms through the:
A) Splitting of large supercooled droplets into smaller droplets as they descend from higher altitudes.
B) Melting of large snowflakes at the base of stratocumulus cloud.
C) Condensation process.
D) Condensation and coalescence processes occurring in stratus cloud.
D
79
Snow falling from a layer of stratocumulus cloud would indicate that:
A) The liquid water content in the cloud is decreasing.
B) The population of large supercooled water droplets will increase in the cloud as the snow continues to fall.
C) An above-freezing layer is present aloft.
D) The liquid water content of the cloud will increase de to the melting of the ice crystals.
A
80
An airport weather observer reports snow grains; this type of precipitation would imply:
A) That freezing rain exists aloft.
B) That a layer of snow aloft had melted and then, during its descent, had passed through a sub-freezing layer.
C) That a layer composed of ice pellets lies above the airport.
D) That freezing drizzle is present aloft.
D
81
A large area of land or ocean of relatively uniform characteristics and above which an air mass can form is known as a:
A) Synoptic region.
B) Source region.
C) Semi-permanent air mass cell.
D) Tropospheric mixing zone.
B
82
A true statement with respect to air masses would be:
A) They have uniform properties of temperature and moisture in the vertical.
B) Air masses are classified according to their moisture content.
C) The transition zone between adjacent air masses is always very wide and diffuse.
D) Air masses are seldom more than several hundred kilometres across.
B
83
When Continental Arctic (cA) air moves southbound over the Great Lakes during the winter you would expect:
A) Steam fog over the southern shorelines.
B) Freezing rain over the southern portions of the lakes.
C) Radiation fog to form over the northern shorelines.
D) Snow showers immediately to the south of the southern shorelines.
D
84
Which of the following would you expect to occur when Maritime Tropical (mT) air moves northwards over the Great Lakes in the spring and early summer?
A) Scattered thunderstorm activity.
B) The formation of nimbostratus cloud layers over the middle of the lakes.
C) Rain showers over the southern shores.
D) Low stratus cloud, drizzle and fog over the north shores.
D
85
As Continental Arctic (cA) air moves southbound over the Great Lakes in early autumn, it often produces:
A) Extensive stratocumulus cloud development over the northern shorelines.
B) Widespread advection fog over the southern shorelines.
C) Steam fog over the northern portions of the lakes.
D) Snow showers over the middle portions of the lakes.
C
86
Fronts are named according to:
A) The steepness of the lapse rate in the warmer air mass.
B) The colder air mass and its direction of movement.
C) The pressure gradient across the frontal surface.
D) The warmer air mass and its direction of movement.
B
87
Which of the following warm fronts would mostly likely be present on Canadian weather charts during the winter months?
A) Maritime Polar and Maritime Tropical.
B) Continental Arctic and Maritime Polar.
C) Maritime Arctic and Maritime Polar.
D) Continental Arctic and Maritime Arctic.
D
88
As you fly towards a warm front where the warm air is moist and unstable, the sequence of clouds that you would expect to encounter would be:
A) CI, CS, AS, NS.
B) CI, CS, AS, NS, and embedded CB’s.
C) CS, AC, SC, SF.
D) CI, CC, ADD, ST.
B
89
The extensive stratiform cloud decks commonly associated with warm fronts are caused by:
A) The cold air being conditionally unstable.
B) Pronounced conductive cooling of the warm air.
C) The cold air having a high relative humidity.
D) Expansional cooling of the overrunning warm air.
D
90
During flight in the lower levels toward a warm front (ie., from the cold air side), you notice that the precipitation changes from steady rain to heavy rain showers. You would assume that:
A) The front was slow moving but had a steep frontal slope.
B) The cold air was moist and unstable.
C) The front had a shallow slope but was retreating rapidly.
D) The warm air was moist and unstable.
D
91
As you fly in the lower levels of the cold air mass side toward a winter warm front (mA air overrunning cA), you encounter ice pellets. In this case, you would know that there was:
A) Very unstable aloft.
B) Freezing rain above.
C) Widespread sublimation occurring in a layer immediately above.
D) A region of dry snow immediately above you.
B
92
Which of the following cold fronts are likely to be found in Canada during the summer months?
A) Continental Arctic and Maritime Arctic.
B) Maritime Arctic and Maritime Polar.
C) Maritime Polar and Maritime Tropical.
D) Continental Arctic and Maritime Polar.
B
93
Cold frontal weather is determined by:
A) The stability of the warm air mass.
B) The moisture content of the warm air mass.
C) The speed of the front and the steepness of it’s frontal passage.
D) All of the above.
D
94
The cloud and precipitation associated with a cold front develops because:
A) The warm air that is in contact with the cold air is cooled conductively.
B) The warm air that is lifted up the frontal surface cools by expansion.
C) The cold air becomes saturated as it overruns the warm air.
D) Advectional heating of the cold air occurs as it advances over ground recently occupied by the warm air.
B
95
A rapidly moving cold front with a steep frontal surface has moved into your region. You note however, that no extensive areas of convective cloud have formed along the front. This would indicate that:
A) The warm air mass has a low relative humidity.
B) An inversion was present in a cold air mass.
C) The warm air must have been conditionally stable.
D) The cold air mass has a low relative humidity.
A
96
An approaching cold front that initially has a shallow frontal surface, steepens some distance behind the surface front. You experience a wind shift and a drop in temperature, when would you expect clouds and precipitation to occur?
A) It would have already occurred.
B) At the same time as the wind shift.
C) Will occur later.
D) No weather change is expected.
C
97
You are at an airport that experiences the passage of a cold front in the early afternoon. Shortly afterwards, the clouds scatter out leaving a clear sky. During the 12 hours, you would expect temperatures to:
A) Decrease, then increase slightly.
B) Steadily decrease.
C) Remain relatively constant.
D) Increase slightly then decrease.
D
98
A cold front with a steep frontal surface that is advancing rapidly upon noise, unstable air produces a suitable environment for:
A) A frontal depression.
B) A squall line of thunderstorms.
C) Orographic subsidence.
D) A “bent back” occlusion.
B
99
A combination of both cold front and warm front weather conditions would most likely be associated frontal wave will tend to be parallel to the:
A) An upper cold front.
B) An occluded front.
C) A trowel.
D) Both (b) and (c) are correct.
D
100
In the Northern Hemisphere, the future of a mature frontal depression and its associated frontal wave will tend to be parallel to the:
A) Isobars behind the cold front.
B) Warm sector isobars.
C) Surface isobars it the air immediately to the North of the crest of the wave.
D) Contours of the 500 hPa surface.
B
101
At a stationary front, the cold air moves:
A) Towards the front.
B) Against a steep surface pressure gradient.
C) Parallel to the front.
D) Away from the front.
C
102
The transition zone between two different air masses where there is a sudden change in temperature and moisture content is called:
A) The mixing zone.
B) A col.
C) A stagnation zone.
D) A front.
D
103
When the properties of two air masses along a front are becoming increasingly different in temperature and moisture content is called:
A) Frontolysis.
B) Cyclogenesis.
C) Frontogenesis.
D) Deepening.
C
104
A land breeze:
A) Blows from the water to the land during the day.
B) Blows from the land to the water during the night.
C) Is always more pronounced and more regular than the sea breeze.
D) May spring up very suddenly, especially during the mid-morning.
B
105
A condition favourable for the development of strong Katabatic winds would be:
A) A region of extensive glaciers.
B) Sloping terrain whose temperature is warmer than the air that rests upon it.
C) An area of gently rolling hills that adjoin a snow-covered plain.
D) Daytime heating of ice-free slopes in the. Canadian Arctic during the summer months.
A
106
A warm katabatic wind found in very hilly terrain is known as a:
A) Mistral wind.
B) Coast winter outflow wind.
C) Bora.
D) Chinook wind.
D
107
Anabatic winds can best be characterized as:
A) Strong winds associated with mid-latitude cyclones and frontal boundaries.
B) A gusty mountain breeze that results from nocturnal cooling.
C) Very cold and intense winds that have been funnelled through narrow mountain passes and are pulled towards low pressure systems to the east.
D) Upslope winds that develop on mountain slopes as they are heated by the sun.
D
108
An aircraft flies over an airport on radar vectors for an approach. The pilot notes that he/she can see the airport through a thin later of fog. What can the pilot foresee as he/she turns onto final approach?
A) The airport will not be clearly seen since flight visibility will be less.
B) The airport will be clearly seen, as there will been no difference in flight visibility.
C) The airport will be clearly seen, as there will be no difference in slant range visibility.
D) The airport will not be clearly seen since slant range visibility will be less.
D
109
What adds to a whiteout illusion (ie no depth perception) besides a snow covered surface?
A) No wind conditions.
B) Uniformly overcast sky.
C) Moderate snow.
D) During the night time hours.
B
110
The requirements for the formation fo all types of fog is:
A) High relative humidity.
B) Cloudless nights.
C) Light breezes that do not exceed 13 kts.
D) The presence of an inversion.
A
111
A south-westerly flow of mT air moving over the Labrador Current would produce:
A) Steam fog.
B) Advection fog.
C) Radiation fog.
D) Adiabatic fog.
B
112
In the answers below, choose the answer that best describes the fog that would develop as the air flows from the Pacific Ocean towards the Rockies:
A) Advection fog.
B) Upslope fog.
C) Radiation fog.
D) Steam fog.
B
113
The fog that forms ahead of a warm front is the result of:
A) Rain that is falling from the overrunning cold air.
B) Radiational cooling of the warm air as it advects over the cold ground.
C) Expansional cooling of the cold air as it is forced aloft.
D) The evaporation of rain as it falls from the warm air into the cold air below.
D
114
Which of the following cooling processes is involved in the formation of the fog that frequently follows a warm front?
A) Expansion.
B) Radiation.
C) Advection.
D) Evaporation.
C
115
Which of the following types of fog forms as a result of raising the dewpoint up to the outside air temperature:
A) Steam fog, Arctic Sea Smoke, and Frontal Fog.
B) Steam fog, Arctic Sea Smoke, and Upslope fog.
C) Steam fog and Advection fog.
D) Arctic Sea Smoke and Upslope fog.
A
116
Steam fog forms when:
A) Warm moist air moves over a cooler surface.
B) A strong wind blows moist, cool air towards the land during the winter.
C) Moist air is cooled expansionally.
D) Water evaporates into very cold air in contact with it.
D
117
When very cold, dry air drifts across the relatively warm waters of lakes, streams or marsh surfaces during cold autumn mornings, you would expect the formation of:
A) Radiation fog.
B) Stratocumulus cloud.
C) Ice fog.
D) Steam fog.
D
118
Both steam fog and radiation fog require which of the following for their formation?
A) Cold, moist air moving horizontally over a cold surface.
B) Condensational nuclei.
C) Expansional cooling.
D) Contact with a surface that is undergoing radiational cooling.
B
119
From the conditions listed below, choose those that are favourable for the production of radiation fog:
1. High relative humidity
2. An overcast sky at approximately the 6000’ to 8000’ ASL level
3. The presence of industrial smoke
4. An air temperature that is much higher than the dewpoint temperature
5. Light winds (2-5 kts)
6. The presence of an anticyclone
7. A very small spread between the frost point and the dewpoint
A) 1, 2, 4, 6
B) 2, 3, 5, 7
C) 1, 3, 4, 7
D) 1, 3, 5, 6
D
120
Radiation fog does not form over the ocean surface since:
A) Favourable low-level, anticyclonic conditions do not prevail over the oceans.
B) The continuous presence of strong winds over the ocean surface prevents radiational cooling.
C) A dry layer aloft that arises from subsidence and which enhances radiation cooling at the surface never exist over an ocean.
D) This surface does not cool by radiation at night.
D
121
The development of radiation fog can be aided by:
A) A mid-level overcast layer of cloud.
B) The presence of pronounced low-level subsidence.
C) The absence of any wind at the surface.
D) The presence of industrial smoke.
D
122
When comparing advection fog to radiation fog, you would know that:
A) Both advection and radiation fog depend on the presence of clear skies at night for their formation.
B) Advection fog requires a considerably higher relative humidity for its formation than does radiation fog.
C) Advection fog can form over both land and water, whereas radiation fog forms only over the land.
D) Both advection and radiation fog require a dry strong wind to assist in their formation.
C
123
Adiabatic cooling causes which of the following types of fog to form:
A) Advection fog.
B) Upslope fog.
C) Radiation fog.
D) Ice fog.
B
124
When moist air moves from the east to west across the Prairies you would expect which of the following to occur?
A) Widespread rain showers and low level turbulence.
B) Extensive build-ups of stratocumulus cloud with good visibilities underneath and moderate turbulence.
C) Unstable conditions with considerable convective cloud development.
D) Widespread upslope fog increasing toward the foothills of the Rocky Mountains.
D
125
The physical process involved in the formation of Ice Fog is:
A) Expansional cooling.
B) Sublimation.
C) Advectional cooling.
D) Condensation
B
126
During the spring, what is the name of the air mass and the associated front that can lead to advection fog occurring in the vicinity of South Western Ontario?
A) Maritime Tropical/Polar Front.
B) Maritime Arctic/Maritime Front.
C) Continental Arctic/Arctic Front.
D) Continental Polar/Continental Front.
A
127
When temperatures are very low, a jet aircraft that takes off from a northern airport can trigger the formation of which of the following types of fog?
A) Upslope fog
B) Prefrontal fog
C) Advection fog
D) Ice fog
D
128
With respect to airframe icing, choose from the factors listed below those that determine the rate of catch (collection efficiency):
1. Supercooled water droplet size
2. The number of freezing layers present
3. The temperature of the individual supercooled droplets
4. The number of supercooled water droplets present
5. Aircraft speed
6. The length of time that the aircraft has been flying in the cloud
7. Shape of the aircraft wing
A) 2, 3, 4, 7
B) 1, 4, 5, 7
C) 2, 3, 5, 6
D) 1, 2, 4, 6
B
129
Large supercooled water droplets are most likely to be found in the:
A) Upper levels of cloud that has formed in stable air where temperatures are well below freezing.
B) Lower levels of cloud that has formed in stable air where temperatures are well before freezing.
C) Upper levels of cloud that has formed in unstable air where temperatures are well below freezing.
D) Lower levels of cloud that has formed in unstable air where temperatures are only a few degrees below freezing.
D
130
If you inadvertently flew through a TCU or CB, you would expect moderate to severe icing down to what temperature?
A) -10 deg C with light icing down to temperatures of approximately -25 deg C
B) -25 deg C with no further icing at colder temperatures
C) -25 deg C with light icing down to temperatures of approximately -40 deg C
D) -40 deg C with no further icing at colder temperatures
C
131
You would expect that rime ice accumulation rather than mixed or clear ice accumulation would occur when the rate of catch is:
A) Low and the droplets are small.
B) High and the droplets are large.
C) Low and the droplets are large.
D) High and the droplets are small.
A
132
During an IFR cross-country flight, your aircraft has been encountering light to moderate mixed icing. You notice that an increasing number of ice crystals are beginning to form within the cloud and would, therefore, expect that the further accumulation type and intensity would change to:
A) Clear icing and increasing intensity.
B) Rime icing and decreasing intensity.
C) Clear icing and decreasing intensity.
D) Rime icing and increasing intensity.
B
133
The shape of the wing is an important factor in determining its collection efficiency. When comparing a thin wing to a thick wing traveling at the same airspeed, it can be demonstrated that the leading edge of a thin wing will collect:
A) The same amount of ice per square inch when flying through cloud whose liquid water content is high.
B) Less ice per square inch.
C) The same amount per square inch when temperatures are not far below freezing and the droplets are large.
D) More ice per square inch.
D
134
With respect to airborne icing, the collection efficiency of a wing would be increased with:
A) Thin leading edges, high speeds and large droplets.
B) Thick leading edges, low speeds and small droplets.
C) Thin leading edges, high speeds and small droplets.
D) Thick leading edges, low speeds and large droplets.
A
135
There is considerable variation in the liquid water content in the vertical of a cloud that has been formed in stable air. In fact, the amount of supercooled water droplets in this type of cloud usually:
A) Remains relatively constant with height when temperatures are far below freezing.
B) Increases with height when temperatures are not far slow freezing.
C) Decreases with height when temperatures are not far below freezing.
D) Increases with height when temperatures are far below freezing.
B
136
Which of the following statements is true with respect to freezing drizzle?
A) This type of precipitation always requires a layer of warm air aloft for its formation.
B) Freezing drizzle always forms a deposit of rime ice on an airframe.
C) Freezing drizzle is most often associated with cumuliform clouds that have a relatively low liquid water content.
D) Icing in freezing drizzle is at its worst near the base of the cloud.
D
137
Freezing rain occurs when:
A) Supercooled water vapour sublimates upon being disturbed.
B) Rain falls into a sub-freezing later of air.
C) Snow melts and becomes very small supercooled cloud droplets.
D) Supercooled rain falls into an above-freezing layer of air.
B
138
Rime ice forms when:
A) Supercooled water droplets partly freeze on contact with the wing leading edge and then flow backwards for some distance before completely freezing.
B) Water vapour sublimates onto an airframe whose temperature is below freezing.
C) Snow or ice pellets adhere to the airframe, then melt and almost immediately refreeze.
D) Supercooled water droplets freeze almost instantaneously without spreading.
D
139
Water droplets instead of ice crystals (IC) exist within the atmosphere at temperatures down to approximately -10 deg C due to the fact that:
A) Ice nuclei are not present until temperatures drop below -10 deg C.
B) Condensation nuclei are too small for a crystalline particle (IC) to form.
C) Condensation nuclei are too big for a crystalline particle (IC) to form.
D) Both (a) and (b) are correct.
A
140
Ice nuclei are important in the formation of snowflakes because it allows:
A) The water vapour molecules to spontaneously freeze onto them.
B) The water vapour molecules to sublimate onto the IC in a crystalline format.
C) The microscopic ice molecules present in the atmosphere to join together and become visible.
D) Water droplets to spontaneously freeze onto them.
B
141
An aircraft that is flying through which of the following phenomena could accumulate a deposit of rime ice on its wings:
A) Snow grains.
B) Hail.
C) Freezing fog.
D) Ice pellets.
C
142
If a METAR is reporting snow grains (SG) or snow pellets (GS), what does this indicate to you?
A) No icing in cloud as they are solid particles.
B) Some type and intensity of airframe icing will be experienced in either situation due to supercooled water droplets present in cloud.
C) Airframe icing if SG is reported but no airframe icing if GS is reported.
D) Airframe icing if GC is reported but no airframe icing if SG is reported.
B
143
Supercooled rain that freezes while falling through a sub-freezing layer becomes:
A) Snow grains.
B) Graupel.
C) Sleet.
D) Ice pellets.
D
144
Snowflakes that receive a coating of rime ice as it falls through a layer of supercooled water droplets and reaches the earth’s surface will be reported as:
A) Ice pellets.
B) Snow grains.
C) Hail.
D) Snow pellets.
D
145
Drizzle that falls through a below-freezing layer and freezes before reaching the earth’s surface will be reported as:
A) Ice pellets.
B) Snow grains.
C) Hail.
D) Snow pellets.
B
146
Aggregation refers to:
A) Water droplets colliding together to form bigger droplets.
B) The growth of snowflakes as they collide together forming larger snowflakes.
C) The transformation of water vapour into water droplets.
D) The transformations of water droplets into ice crystals.
B
147
You have just landed after completing a flight at altitude lasting for several hours. You are to make a station stop lasting about 30 minutes to pick up some passengers before departing without taking on any further fuel. There is light weight wet snow falling at the airport with a temperature of +3 deg C. How and when would you check for surface contamination?
A) It does not matter as the temperature is above 0 deg C
B) Visual inspection just prior to closing the cabin door as you can reading spot any contamination.
C) Tactile feel upon arrival to determine if cold soaking has lead to frost forming.
D) Tactile feel just prior to closing the cabin door as you will be unable to determine visually if the melted snow has refrozen or not.
D
148
The term used to describe the growth of a descending ice particle as it collides with nearby water droplets which then freeze onto the particle is:
A) Aggregation.
B) Frosting.
C) Sublimation.
D) Riming.
D
149
The formation of clear ice on an aircraft is due to:
A) The sublimation of water vapour onto a very cold airframe.
B) The slow freezing of a heavy concentration of small supercooled droplets intercepted by the airframe.
C) The melting and instant re-freezing of ice pellets that impact the airframe.
D) Relatively large supercooled water droplets striking the airframe at a high catch rate which slowly freeze allowing the droplets to spread rearward before freezing entirely.
D
150
Can you take-off with frost on the underside of the wing?
A) No, not under any circumstances.
B) Yes as long as you complete a pre-takeoff deicing procedure.
C) Yes as long as it doesn’t exceed the aircraft manufacturer’s recommendation.
D) Yes as long as the frost on the underside of the wing covers less than 50% of the area.
C
151
Which of the following statements relating to the effects of aerodynamic heating of an airfoil in overall icing conditions is true?
A) An airspeed of 350 to 450 kts is required to de-ice airfoil surfaces.
B) An airspeed of at least 500 kts is required to ensure no ice will collect.
C) There will be an increased risk of leading edge icing if the wing temperature rises to just above 0 deg C.
D) An airspeed of 500 to 600 kts is required to remove any airfoil ice.
B
152
As well as a lifting force or triggering action, the other conditions necessary for the formation of a well-developed thunderstorm are:
A) A low relative humidity and conditionally stable air at the surface.
B) A copious amount of moisture and a stable atmosphere to great heights.
C) A steep lapse rate in the lower atmosphere and a low relative humidity.
D) An abundant supply of moisture and a steep lapse rate.
D
153
The commencement of the dissipating stage of a storm cell is characterized by:
A) Intense rain showers at the surface.
B) The presence of downdrafts throughout nearly the whole cell.
C) The appearance of accessory clouds at the cell’s trailing edge.
D) The domination of updrafts in the interior of the cell.
B
154
Flight beneath the anvil cloud of a thunderstorm cell should be avoided due to:
A) The serious hazard of encountering hail that has been thrown out of this overhanging cloud by the strong upper wind flow.
B) The possibility of entering a region of very large supercooled water droplets, even at temperatures less than -40 deg C.
C) The fact that serious lightning strikes often occur in this region.
D) The possibility of large altimeter errors caused by the accelerated horizontal airflow that exists in this underlying area.
A
155
At what stage of development of a thunderstorm cell would the most serious icing problem be present?
A) Midway through the mature stage.
B) At the beginning of the dissipating stage.
C) Just before the cell enters the mature stage.
D) Midway through the cumulus stage.
C
156
Mammatus clouds are frequently associated with:
A) Violent thunderstorms and tornados.
B) Low level nocturnal jet stream flow over the prairies.
C) Outflow winds from coastal inlets.
D) Frontogenesis of a stationary front.
A
157
What is the name given to a low-level, tube-shaped, detached cloud that is frequently observed on the leading edge side along a line of strong cumulonimbus clouds?
A) Nacreous cloud
B) Shelf cloud.
C) Roll cloud.
D) Undulatus cloud.
C
158
Funnel clouds can form as cone-shaped columns or protuberances extending downwards from the main cloud base of a towering cumulus or cumulonimbus cloud. From the statements that follow relating to funnel clouds, select the one that is false:
A) A funnel cloud is a vortex of condensed water vapour and air spinning at high velocity.
B) If a funnel cloud is in contact with the ground, then it becomes a tornado.
C) Conditions of very low humidity and the absence of vorticity in the air favour the formation of funnel clouds.
D) If a debris swirl is present on the ground underneath a funnel cloud, then meteorologist classify it as a tornado.
C
159
Meteorologists involved with the forecasting of severe weather phenomena would agree that one of the identifiable features associated with tornado development would be:
A) The frequency of upper trough movement over a given area.
B) Satellite measurement of the heat balance in the upper atmosphere.
C) Mesocyclonic movement detected by high-resolution Doppler radars.
D) The continued presence of an omega high over an area which has a very low relative humidity.
C
160
The recommended technique following the inadvertent penetration of a thunderstorm cell is:
A) Slow to turbulence penetration speed and execute an immediate 180 deg turn.
B) Slow to endurance speed and turn 90 deg to your present track to escape.
C) Slow to minimum cruise speed and descend to smoother conditions.
D) Slow to turbulence penetration speed, do not attempt to maintain a rigid altitude or airspeed and maintain present heading.
D
161
An echo that has a distinct hood depicted on an aircraft’s weather radar could be a sign of what?
A) Tornado.
B) Cumulonimbus cells.
C) Severe Icing.
D) Radar malfunctions.
A
162
What distance should thunderstorms be avoided by?
A) 5 nm when below the freezing level.
B) 10 nm when above the freezing level.
C) 20 nm when reported as severe.
D) All of the above.
D
163
Where should you scan a thunderstorm with your weather radar?
A) Start in the mid levels and then below.
B) Start in the mid levels and then above.
C) Start in the high levels and then below.
D) Scan the upper and lower levels and compare intensities.
A
164
The amount of energy that is returned to the weather radar antenna is dependent upon 3 factors:
- The type of the precipitation
- The concentration of the precipitation
- The water droplet’s size
- The are all equally important
Which on one is the most important?
A) The type of the precipitation
B) The concentration of the precipitation
C) The water droplet’s size
D) They are all equally important
C
165
What is an advantage with respect to an aircraft’s weather radar?
A) A radar signal degrades with distance.
B) A radar signal doesn’t reflect well off of solid precipitation.
C) One area of heavy rain blocks out other areas of rain in behind the 1st.
D) Both (a) and (c) are correct.
166
What is an advantage of a storm scope over a weather radar?
A) Not subject to the same amount of attenuation.
B) At lower altitudes, it will detect possible thunderstorms around higher terrain.
C) It tends to be a lower cost item.
D) All of the above.
D
167
Pick the answers that best describe the characteristics of a downburst:
1. Downbursts can be described in terms of size as being “micro” or “macro”.
2. Air within the downbursts tend to be warmer than the surrounding air due to the electrical discharges heating up the air before it descends and strikes the ground.
3. Downbursts are colder than the surrounding air due to the cooling process as the rain droplets partially evaporate as they descend to the ground.
4. Due to the warmer air within the downburst, the speed of the descending air tends to be decreased.
5. Due to the evaporation always cooling effect, the air accelerates downwards increasing the severity of the downburst.
6. A downburst can create both an increased performance shear and/or a decreased performance shear situation for an aircraft on approach or during take-off.
A) 1, 2, 4, 6
B) 1, 3, 5, 6
C) 2, 4, 5, 6
D) 1, 3, 6
B
168
What could the term “Virga” imply in a METAR?
A) That term is reversed for SIGMETs only
B) Snow is falling from the cloud but sublimates before reaching the ground
C) Very Intense Radar Ground Attenuation
D) Microburst
D
169
The shaft of a microburst at the surface is normally about ____ wide?
A) 15 nm or less
B) 2.2 nm or less
C) 5 nm
D) 20 nm
B
170
A large change in wind direction or speed over a short distance is known as:
A) Zonal wind flow.
B) Vorticity.
C) Wind shear.
D) Free convection.
C
171
A condition or phenomenon associated with potentially dangerous wind shear, especially during take-off and landing, would be:
A) A low level temperature inversion (with strong winds above the inversion).
B) A quasi-stationary front that is undergoing frontolysis.
C) A warm high with a mid-level isothermal layer.
D) The presence of an anticyclone that has undergone considerable elongation.
A
172
With respect to low level Nocturnal Jet Streams, which of the following statements are true?
1. They occur mostly in winter.
2. They are always associated with a surface occlusion.
3. They occur mostly in summer.
4. They generally form over flat terrain during the presence of southwest winds.
5. They are usually associated with temperature inversions.
6. They require unstable air up to high altitudes for their formations.
A) 2, 3, 6
B) 4, 5, 2
C) 1, 4, 3
D) 3, 4, 5
D
173
Where is a low level frontal jet stream (LLJ) located?
A) Parallel to the warm front located about 50-100 nm in front of it.
B) Perpendicular to the warm front causing it to rise up along the frontal surface.
C) Perpendicular to the cold front causing it to rise up along the frontal surface.
D) Parallel to the cold front in the warm sector of the frontal wave.
D
174
Where is the CAT associated with the LLJ located?
A) About 1-3 hours prior to the passage of the cold front.
B) Along the cold front.
C) About 1-3 hours prior to the passage of the warm front.
D) Along the warm front.
A
175
When are LLJ depicted in a GFA?
A) When the core speed is expected to be 50 kts or more.
B) When the jet core is located within 6, 000 ASL, except as required over higher terrain.
C) The height of the jet is not indicated.
D) All of the above.
D
176
A pilot taxiing an aeroplane an aeroplane for take-off notes that rain is falling from the base of a convective cloud that is located relatively high above the ground but is evaporating before it reaches the ground. He/she should be aware that this occurrence could signal the presence of:
A) A low level temperature inversion.
B) A dry microburst.
C) A warm occlusion at the 700 hPa level.
D) An air mass within which the environmental lapse rate is considerably less steep than both the DALR and the SALR.
B
177
Which of the following statements is false with reference to ‘dry’ microbursts?
A) They usually occur in areas where the air is very humid.
B) They can often be identified by the presence of ‘virga’.
C) They are linked with high-based cumulus and altocumulus type clouds.
D) With this type of microburst, evaporative cooling intensifies the downdraft.
A
178
Downdrafts associated with a microburst could be as strong as:
A) 2500 feet/minute
B) 4000 feet/minute
C) 6000 feet/minute
D) 7500 feet/minute
C
179
Localized meteorological conditions that produce intense wind shears at Arctic airports as well as at airports situated along the coasts of Canada’s mountainous regions could be due to the presence of:
A) Nocturnal jet stream.
B) High level temperature inversions.
C) Eroding anticyclonic ridges.
D) Valley, katabatic, or funnel winds.
D
180
One of the signposts for the existence of a mountain wave is:
A) Widespread convective cloud development downwind of the mountain range.
B) The presence of very strong anabatic winds.
C) The formation of scud roll cloud downwind from the first wave crest.
D) The presence of altocumulus standing lenticular clouds.
D
181
The lowest group of stationary clouds associated with a mountain wave is:
A) Altocumulus standing lenticular.
B) Rotor cloud.
C) Wall cloud.
D) Altocumulus castellanus.
B
182
Rotor clouds found during mountain wave activity are located:
A) Over the mountain tops several thousand feet above.
B) Located at ridge top heights with their bases often extending below.
C) Beneath the wave crests within the mountain wave.
D) Both (b) and (C) are correct.
D
183
Where are lenticular clouds located in a mountain wave?
A) Over the top of the mountain peaks.
B) At the wave crest.
C) Under the wave crest at ridge-top heights downstream of a mountain range.
D) At the troughs of the mountain waves.
B
184
The most powerful rotor associated with the presence of a mountain wave is located:
A) In the proximity of the first wave crest.
B) Approximately 50 nm downwind from the lee slopes.
C) Always well below the crest of the mountain ridge and usually topped at 2000 feet above the ground.
D) Just below the tropopause, downwind of the third wave crest.
A
185
The part of a mountain wave system that usually presents the most severe turbulence is located:
A) In that area where the cap clouds spill over the leeward slopes.
B) Near the wave that is farthest from the mountain range.
C) Within that layer that is bounded by the ground and the top of the rotor cloud.
D) Just above the downwind portion of each wave crest.
C
186
Severe turbulence at very high altitudes is likely to be associated with a mountain wave system when:
A) A warm high pressure system at the 400 hPa level lies just upwind of the mountain range and parallel to it.
B) The wavelength of the standing wave is less than 5 nm.
C) The air mass is statically unstable and a very unstable layer lies above the mountain range.
D) There is a jet stream wind aloft that is oriented perpendicular to the axis of the mountain range.
D
187
Which of the following statements is correct with reference to a mountain wave system?
A) Altimeter readings are likely to over-read when flying through the crest of a mountain wave.
B) This system can be easily located because characteristic cloud types are always present.
C) The freezing level is at a uniform altitude downwind from the range.
D) The most severe wave is the one that is the greatest distance downwind from the mountain range.
A
188
The tropopause is defined as the boundary between the troposphere and the stratosphere. The tropopause can be identified during a climb in the upper troposphere by the occurrence of:
A) A sudden change in the direction of the thermal wind.
B) An abrupt change in the temperature lapse rate.
C) A marked increase in air density.
D) A dramatic increase in the static air temperature.
B
189
The tropopause:
A) Shows little change in height across upper fronts.
B) Is lower over the equator than over the pole.
C) Is located just above a region of very weak westerly flow.
D) Acts as a lid on the clouds and weather of the tropopause.
D
190
There is an abrupt change in the height of the tropopause over each:
A) Region of surface pressure-field change.
B) Major topographical features such as a prominent mountain range.
C) Latitude interval of 15 degrees.
D) Frontal surface.
D
191
Which of the following air masses would most likely have the highest tropopause height?
A) mT
B) mA
C) mP
D) cA
A
192
The tropopause is:
A) Higher and colder over a warm air mass.
B) Lower and warmer over a warm air mass.
C) Higher and colder over a cold air mass.
D) Lower and colder over a cold air mass.
A
193
With respect to the tropopause, which of the following is a true statement?
A) It is found at a constant altitude over North America.
B) Its altitude is greater over the polar region than over the equatorial region.
C) The International Standard Atmosphere assumes the height of the tropopause to be 39,060 feet ASL.
D) Its altitude is lower over the polar region than over the equatorial region.
D
194
In the International Standard Atmosphere the height of the tropopause and its temperature are specified as:
A) 29, 000 ft and -43 deg C
B) 36, 090 ft and -56.5 deg C
C) 39, 060 ft and -55.6 deg C
D) 45, 000 ft and -75 deg C
B
195
What causes jet streams to form?
A) A strong pressure gradient force between a low and a high pressure area.
B) A strong pressure gradient force that is derived from a strong temperature contrast on the earth’s surface.
C) The Hadley Cell of circulation in the subtropics undergoes a long and slow acceleration as Coriolis deflects the air to the right in the Northern Hemisphere.
D) Both (b) and (c) are correct.
D
196
Along with presence of steep horizontal pressure gradients, which of the following constitutes a major factor in the formation of jet streams?
A) Centripetal force.
B) Linear momentum.
C) Mesoscale force.
D) Coriolis.
B
197
Select the true statement from those listed below concerning jet streams:
A) Jet streams occur on the warm side of the frontal surface with their jet cores positioned just beneath the tropopause.
B) A jet stream located in or near the tropics is generally stronger than one that is present in the mid-latitudes.
C) Extensive, dense cirrus cloud, when associated with a jet stream, is located on the cold air side of the jet core.
D) The cores of jet streams can usually be found just above the warm air tropopause.
A
198
You would expect a north-to-south jet stream flow when:
A) The temperatures below the jet core are colder to the north than to the south.
B) The air beneath the jet stream is colder to the east than to the west.
C) The 200 hPa contours are higher to the north than to the south.
D) The air is considerably warmer than ISA above the jet stream core.
B
199
Why do jet streams suddenly accelerate and decelerate?
A) Centrifugal forces around sharp ridges and troughs.
B) Changing pressure gradient forces along the earth’s surface.
C) Neither (a) or (b) are correct.
D) Both (a) and (b) are correct.
A
200
There are several jet streams that affect the weather in Canada. How are they named?
A) Three of the jet streams are named after their under-lying front, and the fourth is called Subtropical Jet Stream, which is due to the circulation within the Hadley Cell located in the subtropics.
B) All of the jet streams are named after their under-lying fronts.
C) The names are in honour of famous meteorologists.
D) Two of the jet streams are named after their under-lying front, and the third is called the Subtropical Jet Stream derived within the Hadley Cell.
A
201
The height of the jet stream core that is located above the Polar Front is:
A) Lower than the jet stream core located above the Arctic Front.
B) Located at roughly the same height as the one above the Arctic Front.
C) Higher than the Sub Tropical Jet Stream core.
D) Higher than the jet stream core located above the Arctic Front.
D
202
One of the prime areas where CAT (Clear Air Turbulence) is found is in the vicinity of jet streams. Several statements relating to CAT and jet streams appear below. Identify those which are correct:
1. Severe CAT is likely to be present when the vertical wind shear associated with a. Jet stream attains a value of at least 2 kts./1000 feet.
2. The threshold wind speed of a jet stream for the occurrence of CAT is approximately 90 kts.
3. Curving jet streams are more likely to have turbulent edges than straight jet streams especially those which curve around a deep pressure trough.
4. The most severe CAT associated with a very fast-moving jet stream is always located on the high pressure side of the jet stream core.
5. Wind shear and the accompanying CAT adjacent to jet streams are most intense above and to the lee side of mountain ranges.
6. The confluence of two jet streams can be a producer of CAT.
A) 1, 2, 3
B) 2, 4, 6
C) 3, 5, 6
D) 1, 3, 5
C
203
The directional changes that occur as very fast, high level winds flow around upper level troughs and ridges can result in the development of CAT. Select the statement that best describes the shear and resulting turbulence that can be expected with such mesoscale features.
A) Upper level ridges tend to curve more sharply than do upper level troughs.
B) Turbulence associated with upper level ridges usually tends to be more severe than with upper level troughs.
C) Upper level troughs and ridges usually have the same contour curvature since they are both elongation of pressure systems.
D) Turbulence associated with upper level troughs tends to be more severe than with upper level ridges.
D
204
The vertical extent of clear air turbulence associated with a jet stream will be the greatest on the _____ side of the jet stream core. From the choices listed below select the one which is correct.
A) Low pressure, warm air mass.
B) Low pressure, cold air mass.
C) High pressure, warm air mass.
D) High pressure, cold air mass.
B
205
While flying across a jet stream in North America, an aeroplane encounters some CAT. The pilot checks the OAT gauge and notes a temperature rise. To quickly escape from the turbulence, he/she should:
A) Climb the aeroplane.
B) Descend the aeroplane.
C) Alter the aeroplane’s track to the south.
D) Alter the aeroplane’s track to the north.
A
206
Which of the following statements is true with respect to the Polar Jet Stream?
A) Its core speeds will be less when there is a marked temperature contrast across the upper front.
B) This jet stream moves north in the winter and its core speeds are less than in the summer.
C) The most severe turbulence associated with this jet stream is usually encountered on the equatorial side.
D) This jet stream moves south during the winter and generally has higher core speeds than in the summer.
D
207
Jet streams having speeds above _____ at the core will have areas of significant turbulence near them in the sloping tropopause above the core, in the jet stream front below the core and on the cold air (low-pressure) side of the core. Fill in the blank.
A) 50 knots
B) 90 knots
C) 110 knots
D) 150 knots
C
208
Flying near a jet stream in a crosswind situation and encountering moderate CAT, the pilot checks the OAT and notes that it remains constant. In this case, in order to escape from the turbulence, the pilot should:
A) Maintain the current altitude.
B) Alter track so as to parallel the jet stream axis.
C) Alter track to the south.
D) Either climb or descend the aircraft.
D
209
CAT is also related to vertical wind shear, so when the shear is greater than ____ kts/1, 000 feet, turbulence is likely. Fill in the blank.
A) 2
B) 5
C) 10
D) 25
B
