cpl/icjoshi Flashcards
Lowest layer of atmosphere is
a. Troposphere
Height of Tropopause at equator is
b. 16-18 km
Height of Tropopause at Poles is
c. 08-10 km
Higher the surface temperature would be the tropopause
a. Higher
Height of tropopause (not in number)
c. Varies with Latitude
Above 8 km the lower temperatures are over
a. Equator
Atmosphere is heated by
b. Heat from earth surface
Tropos means
a. Turning
CO2 and H2O are also called ___
a. Green House Gases
Troposphere is generally
b. Unstable
Stratosphere is
c. Stable
Tropopause is discontinuous at about
b. 40°Iat
Most of atmospheric mass is contained in ___
a. Troposphere
Stratosphere extends from Tropopause to
a. 50 km
The middle atmosphere layer characterised by temperature inversion and stability…
c. Stratosphere
Mother of pearl clouds occur in ___
c. Stratosphere
The temperature in ISA at 17 km is ___
a. -56.5°C
By weight, approximate ratio of O2 to N2 in the atmosphere is
a. 1:3
By volume, the approximate ratio of O2 to N2 in the atmosphere is
b. 1:4
By volume, the proportion CO2 in the atmosphere is
c. 0.03%
In ISA, the mean sea level temperature is
a. 15° C
Maximum concentration of ozone is at 3 height of
b. 20-25 km
Additional oxygen is needed while flying above
c. 10000 ft
CO2 and H2O keep the atmosphere
a. Warm
Noctilucent clouds occur in
b. Mesosphere
Temperature at 2 km is 05 °C what is ISA deviation
03* c
Pressure at MSL is 1002.25 hPa. Find the ISA deviation
a. -11 hPa
In actual atmosphere temp, at 19 km is -60°C. How much it differs from ISA
c. -03.5°C
Winds in a low pressure
a. Converge
Low pressure is associated with
b. Bad Weather
In a high pressure area winds are
c. Weak
Flying from Low to High an altimeter would read
b. Under
Isallobars are lines of equal
c. Pressure Tendency
What kind of a barometer is an altimeter?
a. Aneroid
A region between two Lows and Two Highs is
c. Col
Bad weather and better visibility is associate with
b. Low
The relationship between height and pressure is made use in construction of
a. Altimeter
Altimeter always measure the ht of aircraft
c. Above datum level at which its sub-scale is set
Two aircraft flying at the same indicated altitude with their altimeter set to 1013.2 hPa. One is flying over cold air mass and other over warm air mass. Which of the two has greater altitude?
a. Ac flying over warm air mass
The rate of fall of pressure with height in a warm air mass compared to cold air mass will be
c. Less
An increase of 1000 feet in elevation near the earth is associated with decrease of pressure of
d. 33 hPa
Lines drawn through places of equal pressure are known as
a. Isobars
Isoclinal
b. After crossing the axis of trough winds back
Diurnal pressure changes are most pronounced in
c. Tropics
Flying from Delhi to Calcutta at constant indicated altitude but, experiencing a drift to Starboard. The actual altitude will be ___ (Vis-a-vis) indicated altitude
a. Lower
In the Southern Hemisphere, around a Low Pressure Area wind blows
a. In clockwise direction
If altimeter reads aerodrome elevation when a/c is on ground, its sub-scale must have been set
a. QNH
Instrument for recording pressure is called
b. Barometer
Poor visibility is associated with
a. High
On either side of ___ pressures rise
a. Trough
Fall of pressure with height is more rapid in
a. Cold areas
300 hPa in ISA corresponds to the level
b. 30,000 ft
18,000 ft height in ISA corresponds to level
c. 500 hPa
200 hPa in ISA corresponds to the level
c. 40,000 ft
24,000 ft height in ISA corresponds to level
a. 400 hPa
700 hPa in ISA corresponds to the level
b. 10,000 ft
40,000 ft height in ISA corresponds to level
c. 200 hPa
850 hPa in ISA corresponds to the level
b. 5,000 ft
Diurnal variation of temperature is greatest when wind is
a. calm
Diurnal variation of temperature is maximum over
c. land
On a clear day the amount of radiation received by earth surface is
c. 5/6 th
ALBEDO is
c. Reflecting power of earth
During Day the ambient temperature is … than ground
a. Lower
Diurnal variation of temperature over ocean is …
c. Less than 1°C
At a coast diurnal variation of temp, depends on ..
a. Wind direction
Snow surface reflects about % of solar radiation.
b. 80%
Amount of Solar radiation received per unit area is … ( not in number)
a. Insolation
Solar radiation received by the earth is called ___
c. Shortwave
Rise in temperature of a surface is ___ proportional to its specific heat
b. Inversely
Specific heat of land is ___ than that of water
a. Lower
Minimum temperature is reached at …( not in degree)
c. 1/2 - 1 hour after dawn
An air parcel is lifted till it gets saturated. The temperature attained at this stage is called
b. Dew Point
Cloudy nights are
c. warm
Water vapour is transparent to terrestrial radiation
b. partially
Higher the temperature … would be the wavelength of emitted radiation
b. shorter
Air is a bad conductor of heat. A parcel of air can therefore be regarded as insulated from the environment
b. True
Warmer the earth ___ will be the Nocturnal radiation
a. lntense
Heat is the of the KE of all molecules and atoms of a substance
a. sum total
The solar radiation consists of about 46 %
b. IR
The total amount of energy radiated by a black body is proportional to
c. T4
Intense radiation are emitted by
a. Hot bodies
The wavelength of most intense radiation is inversely proportional to the….
a. Absolute temperature
Hot bodies (like sun) radiate
a. Short Waves
The flow of heat from earth surface is 77% by
b. Latent Heat
-40° C = -40° F
a. True
Surface Temp, is recorded at a height of above ground
b. 1.25m
The door of Stevenson’s screen should open
a. opposite to sun
The liquid used in Minimum Thermometer is
b. alcohol
Density is ___ at poles than equator
a. Higher
Above 8 km density is ___ at poles than at equator
b. Lower
The altitude in ISA at which air density is the same as the observed density is called
a. Density Altitude
Density is usually expressed as
b. g/cu m
Higher density altitude means ___ density
b. Lower
For given pressure and temperature moist air has density
b. Lower
Air is less denser in
d. All these
Density altitude may be defined as:
b. The altitude in a standard atmosphere at which the prevailing density occurs.
The ratio in % between the amount of water vapour present in the air to the amount of water vapour that it can hold at the same temperature is
b. Relative humidity
The temperature to which air be cooled at constant pressure to become saturated, is called
c. Dew point
Free air temperature, Wet bulb temperature and Dew point temperature are equal when
b. Relative humidity is 100%
On a rainy day compared to sunny day the length of runway required is
a. More
The spread between Free air temperature and Dew point temperature is …. when air is saturated
b. Least
The saturation vapour pressure over water is ___ than the ice
a. More
As the temperature of the air increases, the amount of water vapour required to saturate it
b. increases
The actual amount of water vapour contained in a given volume of air at a given temperature is termed as …
c. Absolute Humidity
Humidity Mixing Ratio ___ when air is lifted adiabatically
b. remains constant
It is the lowest temperature which air would attain by evaporating water into it to saturate it.
a. Wet bulb temp
In S hemisphere if an observer faces wind, low will be to his
b. Left
In N hemisphere due to rotation of earth winds are deflected to
b. Right
Local Winds follow Buys Ballots law
a. False
Coriolis force acts perpendicular towards ___ of wind direction
b. Right
Geostrophic wind is due to the balance between the forces
c. Pressure gradient and Coriolis
Coriolis force is strongest at
b. Poles
Geostrophic rule breaks down at
c. Equator
Fohn winds are ___ on the Leeward side of a mountain,
a. Dry & Warm
The wind sliding down a hill during night is called ___ wind.
c. Katabatic
With the onset of sea breeze there is a ___ in temperature and ___ in RH.
a. Fall/Rise
Sea breeze sets in by ___ and dies off at ___
b. Day/Night
- If an aircraft in N-hemisphere flies from H to it will experience
a. Starboard drift
In N-Hemisphere if you experience Port drift , altimeter will ___ read
a. Under
Lines of constant wind speed drawn on weather charts are called
b. Isotachs
Squall are distinguished from gusts by:
b. Longer duration
The thermal wind is:
c. The wind which must be added vectorilly to the lower level geostrophic wind to obtain the upper level geostrophic wind
On a weather map where isobars are closely packed, the surface winds are likelyto be
b. Strong and parallel to isobars
Anabatic wind occurs ( time)
c. During day
Anabatic wind is stronger than katabatic
b. False
Katabatic wind is down slope cold wind due to nocturnal cooling
a. True
Katabatic wind occur due to sinking of air down the hill slope
a. True
Anabatic wind occur due to downward movement of air along valley
b. False
Sea breeze is stronger than land breeze
a. True
The wind blows clockwise around low in a N-hemisphere
b. False
The wind blows clockwise around low in S-hemisphere
a. True
The wind blows anticlockwise around low in N-hemisphere
a. True
The wind blows anticlockwise around low in S- hemisphere
b. False
The resultant wind that blows under the influence of pressure gradient force, geostrophic force and cyclostrophic force is called
a. Gradient wind
Due to friction, from day to night for an isobaric pattern (in N hemisphere) Surface wind backs and lulls
a. True
The winds which spiral inward in a counter-clockwise direction in the NH are associated
with
c. Low pressure area
Lower level wind 05010 kt, upper level wind 23005 kt, what is the thermal wind
b. 23015 kt
A change in wind direction from 310° to 020° is
b. Veering
A change from 270° to 250° is
a. Backing
Sudden change in wind speed from 10 kt to 30 kt and then to 15 kt is
a. Gust
Sudden change in wind speed from 10 kt to 30 kt for more than a minute or so is
a. Squall
A significant wind shear can be associated with TS or line squall
b. True
Cyclostrophic wind gives a good approximation of the 2000’ wind in an intense tropical
storm
a. True
Rotor clouds have extremely turbulent flying conditions
b. True
Friction causes winds to flow cross isobaric by ___ over land and ___ over sea
a. 20/10*
If temperature is higher to the S and lower to the N from surface up to higher levels , then the wind will strengthen with height with no change in ___ direction in N hemisphere (direction)
b. Wly
Gradient wind is ___ of geostrophic wind in an anticyclone
c. Over estimate
Gale is
c. persistent strong winds exceeding 33 kt, associated with depression
In N hemisphere thermal wind is parallel to ___ with low value to left
b. Isotherms
Fog is reported when visibility is reduced to
a. Less than 1000 m
RVR is reported when visibility falls below
c. 1500 m
Radiation fog occurs
a. Over land
When visibility reduces between 5000 m and 1000 m and RH is almost 100%, it is
a. Mist
Radiation Fog forms over N India during ( months)
b. Dec to Feb
Warm and moist air moving over a cold ground gives rise to:
b. Fog and stratus
Warm and moist air moving over a cold surface causes
b. Advection Fog
The radiation fog forms due to
b. Radiational cooling of earth at night
The radiation fog activity increases after the passage of a…
a. WD
Radiation fog is essentially a ___ phenomena
a. Nocturnal
The radiation fog forms over
b. Land
The ___ fog forms due to horizontal movement of air
b. Advection
Advection fog forms during ( time)
c. any time of day and night
For formation of Radiation fog
b. There should be sufficient moisture in atmosphere, clear sky, light wind.
Instrument used for measuring visibility…
b. Transmissometer
Advection fog forms
c. both over land and sea
Drizzle occurs from
b. ST
Altostratus (AS) is
b. A medium cloud of sheet type
Showers occurs from
b. CB
Heavy icing is possible in
d. CB
To avoid icing in cloudy conditions, a pilot is advised to fly through a cloud which shows an optical phenomena
a. Halo
Dark gray cloud giving continuous rain is called
b. NS
A uniform layer of cloud resembling fog but not on the ground
c. ST
The clouds composed of ice crystals having feathery appearance
a. CI
NS clouds occur
b. At warm front
Halo is associated with the cloud
c. CS
Corona is associated with the cloud
a. AS
Lenticular clouds indicate presence of
c. Mountain waves
The lowest level below which condensation trails will not form is
a. Mintra Level
Rain falling from cloud but not reaching ground is
b. Virga
CB with distinct anvil is called
b. Capillatus
Cloud ceiling is the height of the cloud covering
c. 5/8 or more
No condensation trails occur above
a. Maxtra Level
Cloud of operational significance has base below m or below the highest minimum sector altitude, which is greater
a. 1500
AC cloud with cumuliform protuberances are indicative of
b. Instability
Hail may be experienced under the anvil of a CB
a. True
DALR = 9.8 °C, ELR = 6.8 °C ; atmosphere is
a. stable
SALR = 5.5 °C, ELR= 4.5 °C ; atmosphere is
b. stable
DALR > ELR > SALR
a. conditionally unstable
Dry air is unstable when
b. ELR>DALR
The saturated air is said to be unstable if
b. SALR
If ELR = SALR - DALR the atmosphere is
c. Indifferent
DALR means:
a. The rate at which temperature of unsaturated parcel of air falls with height
The surface air temp, is 30° C. Assuming DALR prevailing what is the temperature at 2 km
b. 10° C
An Isothermal atmosphere is
a. Stable
If environmental lapse rate(ELR) is less than SALR, that part of the atmosphere is said to be:
c. Absolutely stable
DALR is approximately
c. 10 ° C /km
SALR at mean sea level is about
b. 5 ° C/Km
SALR approaches DALR
c. at -40°C
Dry air having a temperature of 35°C on surface when forced to rise adiabatically by 1 km would attain a temperature of
b. 25°C
Inversion in the atmosphere indicates
a. Stability
Inversion is ___ Lapse Rate (LR)
b. Negative
Environmental LR can be more than DALR
a. True
The process which to a large extent determines the vertical distribution of temperature in atmosphere is
a. Adiabatic
Rise in temperature with height is
a. Inversion
Inversion is common in (season)
c. Winters
Aurora Australis occur in the
a. S hemisphere
Aurora Australis called ___ Lights
b. Southern
Aurora Borealis occur in the
b. N hemisphere
Aurora Borealis are called ___ Lights
a. Northern
Corona occur in ___ clouds
a. AS
Bishop’s ring is due to the diffraction of light by fine particles of
b. dust
The radius of the Bishop’s ring is about
b. 22°
Superior Mirage occurs in marked
c. Inversion
Inferior Mirage occurs when there is
a. Lapse
Corona are formed due to the ___ of light
b. Diffraction
Corona are formed due to light, passing through
d. Any one of all these
Halo is produced by
a. Refraction
Halo is produced when light passes through
b. ice crystals
Halo occur in the cloud
c. CS
Halo is luminous ring of ___ radius
b. 22°
Halo round the sun shows a pure clear ___ on the outside
a. Red
Halo signifies predominance in the cloud of
b. Ice crystals
The cloud which cause Halo has ___ chances of ice accretion
a. negligible
Sometimes a halo with a radius of ___ is observed, called Large Halo
b. 42°
Halo occurs from ___ cloud
c. High
When super cooled water drops and ice particles co-exist, the ice crystals grow at the expense of the water drops because
b. Saturation vapour pressure over the ice crystals is less than over water drops
The clouds whose tops extend well above the freezing level are called
b. Cold Clouds
The clouds whose tops do not extend to the freezing level are called
a. Warm Clouds
Coalescence Theory explains occurrence of rainfall from the
a. Warm Clouds
Ice crystal Theory explains occurrence of rainfall from the
b. Cold Clouds
Giant Nucleus Theory explains occurrence of rainfall over
a. Maritime areas
Very heavy precipitation as showers over a short period is called
b. Cloud Burst
Rain shadow area is on the of the mountain range
c. Leeward side
Sleet is a mixture of
b. Rain & Snow
Rainfall in the tropics is more in (season)
b. Summers
Rainfall in the tropics is more in the (time)
b. Afternoon
Rainfall in the temperate latitudes is more in (season)
a. Winters
Over J&K and western Himalayas Rainfall is more in (season)
a. Winters
Rainfall over coastal areas is more in the(time)
c. Night & early morning
Areas to the_____ of western Ghats of India are rain shadow areas (direction)
c. E
A sudden rise in the level of rivers or streams causing floods is called
c. Flash Floods
Artificial rain making is also termed as
b. Cloud seeding
Fog can be dispersed for a short period by artificial stimulation
a. True
Showery precipitation occurs from
c. CB
A day is called Rainy day when rainfall in 24 hr is ….mm or more
C.2.5 mm
Hoar frost occurs on airframe in clear air when the temperature of airframe is ( not in numbers)
a. below the frost point
In clouds at temperatures below 0° C an aircraft may encounter icing of the type
c. intermediate between these two
Opaque Rime ice is
a. Light porous
Rime is formed by freezing of ___ supercooled water droplets on aircraft is flying through clouds
a. Small
The ___ ice poses serious aviation hazard
C. Glazed
Airframe icing occurs below 0°C. Its probability of occurrence decreases progressively below -20 °C, as at lower temperatures the proportion of supercooled water drops in a cloud
b.Decreases
CI, CS and CC clouds consist mostly ice crystals. Icing hazard is therefore
C. Negligible
AS, NS consist of supercooled water drops and ice crystals in varying proportion icing is possible.
Light or moderate
In AC clouds ___ icing is likely in mountainous areas
C. Severe
In TCU icing may range from light to severe type at least up to ___ level. (Degree)
c. - 20 °C level
In CB icing may range from light to severe type up to -20°C level. Below this temperature severe icing is
a. not significant
Liquid water content is an important factor in icing. As the maximum water concentration is around , maximum ice formation in clouds may also be expected around that level. (Degree)
c. -15° C level
Carburetor icing occurs when air from intake passes through a ventury (choke) and causes expansional cooling and vaporization of fuel. Serious icing can occur at extreme temperatures (degree)
b. 30°C to -10°C
___ occurs in a moist cloudless air on an aircraft surface having temp, below 0° C, due to sublimation of water vapour onto feathery ice crystals.
c. Hoar Frost
___ occurs in St, Sc, Ac, Cu, Ns at temperature -10 to -40° C and in Cb at temperature -20 to -40°C
a. Rime
In clouds ___ occurs when a wide range of water drop sizes are present at temperatures between 0° C and -40° C
c. Mixture of rime and clear ice
___ occurs in AS, NS, SC and towering CU or CB between 0° C and -20° C, in warm front below 0° C, especially if the aircraft has rapidly descended from a colder region
a. Glazed
When fog freezes on parked aircraft it produces ___
a. Hoar Frost
Icing the stalling speed appreciably
b. Increases
The condition necessary for the formation of a thunderstorm are:
c. Steps lapse rate ,adequate supply of moisture and trigger action.
Hail is most likely to fall from a cloud
c. Having strong vertical development
Nor westers are
b. Severe thunderstorms which occur over NE India during hot weather periot
Duststorm usually occurs over NW India during (season)
c. Pre-Monsoon
A ‘mature’ thunderstorm has
c. Strong updrafts and downdrafts
Aircraft icing is most favoured in the cloud which have temperatures ranging between (degrees)
b. 0° C and - 20° C
A short duration, showery precipitation is associated with
c. CB
Hail is
c. Solid precipitation falling from a deep convective cloud
The most hazardous cloud for aviation is
a. CB
The life of a Cb cell is usually
c. 1/2 - 1 hr
Generally the severest activity of a CB clouds is for
b. 30 to 45 min
Norwesters occur during ( months)
b. Mar-May
Norwesters occur during
b. Hot weather
Norwesters affect (area)
b. Bengal, Bihar, Orissa and Assam
The trigger action may take place due to
b. Orographic lifting
Norwesters normally occur during (time)
b. Afternoons
Norwesters originates over
a. Chota-Nagpur hills
Andhi (blinding storms) occur generally over
b. N India
Wind speed in Light DS is
c. up to 21 kt
The diameter of Microburst is
a. less than 4 km
The diameter of and Macroburst
b. 4 km or more
For detecting precipitation a Radar wavelength in the range ___ is suitable
a. 30 to 200 mm
For airborne radars wavelength generally used
c. 60 mm
The wavelength of TS detection X band radar is
c. 30 mm
The wavelength of storm detection S band radar is
b. 100 mm
Over plains TS mostly occur during the (time)
a. afternoon
Over valley and foot hills TS generally occur during (time)
b. night & early morning
Over the sea TS are more frequent (time)
b. night
The life of Mesoscale Convective Complex TS is
c. 6 to 24 hr
Loud peals of thunder, frequent flashes of lightning, moderate or heavy showers accompanied by light hail with maximum wind speed 15-40 kt is classified as
b. Moderate TS
For a severe TS one of the requirements is strong wind shear
b. Vertical
Severe TS cells are tilted
a. in vertical
The air mass which originates at sea in low Latitudes is called
a. Polar maritime
The air mass which originates over equatorial region is
b. Warm & Moist
If the advancing cold front is colder than the cool air mass of the warm front, the advancing cold front undercuts and lifts both the warm and cool air masses of the warm front. This is
a. Cold Occlusion
The airmass which originated over land area located in polar region:
c. Cold & dry
If a warm airmass overtakes a cold air mass, it is called
b. Warm Front
At warm front
a. Warm air overtakes the cold air
The conditions are always unstable at
a. Cold front
Line squall occurs about 100-300 km ahead of
b. Cold front
Precipitation occurs over a belt of 30 - 50 km on both side of front
a. Cold front
Cold front moves at ___ the speed of a warm front moves
b. Double
Line Squalls occur ___ of Cold front
a. Ahead
Fronts are associated with
c. Extra-tropical Cyclones
CB, Roll-type clouds, SC, AC with embedded CB are associated
a. Cold front
The Surface of discontinuity between the Polar Easterlies and the temperate Westerlies is called
c. Polar Front
The air mass which origir>ates from sea area located in lower Lat is
B. Warm & Moist
WDs approach India as
b. Occluded Fronts
Maximum WDs occur in (season)
c. Winters
Ahead of a warm front the surface wind
B. Veers & strengthens
On approach of a Warm Front temperature
b. Rise
CI, CS, AS, NS, ST in sequence are associated with the front
a. Warm
During the passage of a Cold Front winds
a. Suddenly become squally
Visibility is poor in a Warm Front
b. Ahead & During
Fog occurs in Cold Front
c. After
WD is a ___ front
C occluded
FZRA and FZFG occur ___ of a warm front
a. Ahead
Precipitation ceases after the passage of a front
b. Warm
During the approach of a Warm Front wind
a. Backs
Whenever the low of a WD has two or more closed isobars, at 2 hPa interval, it is termed as
b. Western Depression
The arbitrary lower limit of jet core velocity has been assigned by WMO as
a. 60 kt
Jet stream has
b. one or more maxima
The vertical wind shear in a Jet stream is about
a. 5m/s/ km
Compared to horizontal wind shear the vertical wind shear in a Jet stream is
Stronger
In a jet stream, the path of the maximum speed is known as
b. Axis
The wind speed along the axis of a jet stream is always
b. Not uniform
Along the axis of a jet stream there are centres of high speed winds, these are called
a. Jet streaks
In a wavy jet the Jet streaks are located over or near the
a. Ridge
Sub-tropical Jet Stream (STJ) is (direction)
a. Westerly
The normal position of Sub-tropical Jet Stream is
b. 27° N
The southern most position of STJ is in February is
b. 22° N
The STJ affects India from (months)
b. Oct to May
STJ has a layered structure. There are often two layers of maximum wind to the ___ of jet core (direction)
a. S
The STJ strengthens
c. Downstream
At and near the STJ the temperature gradient is very
a. Small
Vertical wind shear in STJ is greater the core
a. above
The TJ prevails over the Indian Peninsula from (months)
c. Jun to Aug
The TJ is located over the Indian Peninsula, approximately at
a. 13° N
The TJ is located over Indian, approximately at a height of
a. 15 -16 km
The TJ is strongest in (months)
a. July - Aug
In the TJ the wind shears are much ___ than the STJ
b. less
TJ is (direction)
b. Easterly
For mountain waves to form there should be flow of air across the ridge, generally within ___ of the perpendicular to the ridge.
a. 30°
For mountain waves to form the wind speed for small mountains should be atleast
c. 7m/s
For mountain waves to form the wind speed for large mountains should be atleast
a. 15 m/s
For mountain waves to form the atmosphere should be ___ up to the ridge, where air stream strikes the ridge.
b. Stable
For mountain waves to form the atmosphere should be ___ at higher levels above the ridge
a. Unstable
In Mountain waves the Rotor clouds form in
b. Ridges
Clear air turbulence is often encountered
d. All of the above
Most CAT occurs on the ___ of a jet stream and in the vicinity of upper level frontal zones where temperature contrasts are strong.
a. Fringes
CAT is the bumpiness experienced by aircraft at high altitudes ___ in either cloud-free conditions or in stratiform clouds
a. above 18,000 feet
When approaching an area where mountain waves have been reported, a pilot should expect:
d. All of the above
Wind speed in a tropical severe cyclone is:
b. 48 - 63 kt
Fronts are characteristic of:
b. Extra-tropical depressions
During re-curvature, maximum weather in a monsoon depression occurs in
d. NE sector
On whatever compass course the cyclone is approached, strong winds from the port indicate that the centre lies somewhere
a. Ahead
The well developed extra tropical cyclonic storm is composed of two main frontal systems and an occluded front, which varies in extent:
b. A low with a warm front radiating out Southwards followed by a cold front.
The weather expected in a well developed cyclonic storm is:
b. Stormy weather
Cyclone always approach land areas before they die
a. True
The ___ is the most dangerous part of the cyclone is
a. eye wall
No CS form
b. At Equator
Life cycle of a tropical cyclone in India is
a. 3-4Days
CS in Indian region are less intense because
a. They have a very short travel over the sea
CS in India are mostly of intensity
c. Moderate
Eye of a CS is surrounded by
b. Wall Clouds
Surge is sudden strengthening of wind in the ___ air mass
a. Same
During winters
c. Activity of Radiation fog increases after the passage of a WD over N India
Low Temperatures and low humidity is the characteristic of (season)
D. Winter months
Hot weather period is ( months)
b. Mar-May
During hot weather
a. WDs cause TS / DS over Punjab & Rajasthan
The monsoon current over the West coast of India is (direction)
a. SWly
Monsoon period is ( months)
c. June to Sep
The monsoon advances with
c. Bay of Bengal and Arabian sea currents
The rainfall over India during monsoon depends on
c. The position of the axis of Monsoon Trough
Rainfall occurs all over the country during monsoon when
a. Axis of MT is in its normal position along Gangetic plains
Break in monsoon occurs when
b. Axis of monsoon trough is along foot hills of Himalayas
With a depression over the head Bay fair weather during monsoon occurs over
a. Assam
Monsoon is also called
b. SW monsoon
Post monsoon weather period are (months)
c. Oct to Dec
During post monsoon, pressure gradient over India is
a. weak
During monsoon period, low pressure lies over
d. Pakistan
During vigorous monsoon period the pressure gradient over west coast is
b. Steep
An aircraft flying in Monsoon season from Chennai to Kolkata at 14 km will experience
winds
a. Easterly
An aircraft flying in Winter season from Chennai to Kolkata at 12 km will experience winds
b. Wly
An aircraft flying in Pre monsoon season from Delhi to Kolkata at 10 km will experience winds
b. Westerly
An aircraft flying in Monsoon season from Mumbai to Ahmedabad at 03 km will experience winds
b. SWIy
An aircraft flying in winter season from Delhi to Kolkata at 06 km will experience winds
d. NW - Wly
An aircraft flying in winter season from Delhi to Kolkata at 06 km will experience
a. Port drift
An aircraft flying in winter season from Kolkata to Nagpur at 02 km will experience
a. Port drift
During break monsoon the pressures all over the country
a. Rise
During break monsoon sometimes the surface winds over East UP and Bihar are
a. very strong
Mid tropospheric cyclone occurs during
d. SW monsoon
Mid tropospheric cyclone during monsoon form over
c. Gujarat
El Nino episode is applied by fishermen to a period of reduced fish catch due to suppression of upwelling
a. warm surface coastal current
Maximum cyclones occur over India in (season)
c. Post monsoon
Tropical Jet stream occurs in India during
d. SW monsoon
Pressure gradient over West Coast of India is steep during
d. SW monsoon
During break in monsoon rain occurs
a. along foot hills
The polewards moving air piles up in the subtropical regions and forms high pressure belt at the surface, called
(a) Subtropical high
___ occurs over subtropical high
(c) subsidence
The occurrence of large deserts near 30N and 30S are due to large scale
(a) subsidence
A part of the sinking air over the subtropical highs flows towards the equator, turning west (in the northern hemisphere) due to the Coriolis force. This surface air is called
(c) Doldrums
The huge vertical circulations, one between the equator and 30N and another between equator and 30S, are called
(a) Hadley Cells
The descending branch of the Hadley cell marked by calm winds and high pressure ar the surface are called
(c) Horse Latitudes
The winds in the upper troposphere are westerly. These are known as
(c) Zonal Westerlies
In the equatorial regions the upper tropospheric winds are (direction)
(b) Easterlies
The disturbances of middle latitudes move from (direction)
(a) W to E
The tropical disturbances which form in the equatorial low pressure belt move in
(b) Westerly direction
Tropical disturbance which reach the zone of transition in the upper level flow change course and begin to move in a
(b) Opposite direction
Latitudinally, on the average there is radiation in the tropics than in the polar regions
(a) surplus
The systems like highs, lows, cyclonic circulation etc are associated with distinct types of weather. A study of the behaviour of these systems, known as
(a) Synoptic Meteorology
Rising air creates calms or doldrums in the equatorial region
(c) Equatorial Doldrums
Steady NE winds in the N hemisphere and SE winds in the S hemisphere are called:
{b) Trade Winds
For non-scheduled National Flights an advance notice (before ETD} is required to be given to AMOs
(a) 3 hr
For non-scheduled National Flights an advance notice (before ETD) is required to be given to AMSs
(b) 18-24 hr
WAFS provides high quality en-route forecasts of ___ to Met Offices.
(a) high quality en-route forecasts of winds and temperature
IMD has ___ Regional Met offices
(c) 6
There are ___ Aerodrome Met Offices
(b) 17
There are ___ Aeronautical Met Stations
(b) 51
In AIREP the Met Information is contained in Section
(c) 3
TAF are generally valid for
(c) 9hr
The validity of Landing Forecast (TREND) is
(b) 2 hr
Landing Forecast is append to
(a) METAR and SPECI
Local Forecast is issued three times a day valid for next
(b) 8hr
Local Forecast covers an area
(a) 50 NM
Prognostic Charts are issued by
(a) RAFC
Prognostic Charts are valid for
(b) 12 hr
SIG Wx Chart are issued for Flight Levels
(a) below 460
CODAR is
(c) Upper report from an aircraft (other than weather reconnaissance aircraft)
WINTEM is
(b) Forecast upper wind and temperature
SIGMET is a notice of severe weather for
(c) both, actual & expected
SIGMET is issued for aircraft
(a) in flight
SIGMET is issued by
(c) MWO
SIGMET is valid for
(a) 4 hr
SIGMET is nor issued for
(a) Rain
AIRMET is SIGMET issued by a MWO for the safety of
(a) low-level aircraft
GAMET is an area forecast in abbreviated plain language for
(b) low-level aircraft
The validity of Airfield warnings is not exceeding
(b) 4 hr
Airfield warning is issued for expected wind speed
(a) 30 kt
Airfield warning is issued for wind direction of 20 kt changes by
(a) 45°
Airfield Warning for gliders, light aircraft and helicopters is issued for expected wind speed
(b) 17 kt
Wind Shear Warning is issued for the observed or expected wind shear above runway
(a) up to 500 m
VOLMET is a MET information for aircraft
(b) in flight
VOLMET Radio Telephony Broadcast made on HF Channel from
(c) both, Mumbai & Kolkata
VOLMET consists of
(c) TAF and METAR
In ROBEX the METAR/SPECI of international aerodromes and their alternates is exchanged
(b) outside India
SIG Weather Charts are issued ___ times a day
(c) Four
Visibility is reported in steps of 50 m when visibility is
(b) 0 to 800 m
Visibility is reported in steps of 100 m when visibility is
(a) 800 m to 5000 m
Visibility is reported in steps of 1000 m when visibility is
(c) 5000 m to 9999
Visibility is reported 9999 when visibility is
(c) 10 km or more
Temperature + 2.5°C is reported as
(b) 3°C
Temperature 12.5°C is reported as
(c) M 12
Pressure is rounded down to the nearest whole number in hectopascal
(c) lower value
QNH 1002.6 hPa is reported as
(a) Q1002
QNH 29.92 inches is reported as
(b) A2992
Fog is reported when visibility is
(a) < 1000 m
Mist is reported when visibility is
(b) 1000 to 5000m
CAVOK signifies Visibility, Cloud ___ and present weather better can the prescribed values or conditions
(a) ceiling
CAVOK is issued when visibility is
(b} 10 km or more
CAVOK is issued when
(i) Visibility 10 km or more
(ii) No weather of significance.
(iii) No clouds below 1500 m or below the highest minimum sector altitude, which ever is greater and no cumulonimbus.
(c) All the three conditions
SPECI is issued when
(i) Change in wind direction is ≥ 60° and speed before and/ after change ≥ 10 kt
(ii) Mean speed has changed by ≥ 10 kt
(ill) Variation from mean speed by ≥ 10 kt and speed before and/ after change ≥ 15 kt
(b) Any one condition
SPECI is issued when Clouds are (i) BKN or OVC base at 30, 60, 150, 300, 450 m (ii) Cloud amount below 450 m changes: From SKC/ FEW/ SCT to BKN / OVC OR From BKN/ OVC to SKC/ FEW/ SCT.
(a) Any one condition
SPECI is issued for vertical visibility, by stations having Ceilograph, when sky is
(a) True
WSRWY28 indicates that the wind shear has been reported for RW 28 in
(c) both take off and approach paths
R26/M0150 in a METAR indicates that
(c) 150 m is the lowest RVR instrument can measure and RVR is less than 150 m
Nacreous cloud occurre in
Upper stratosphere
The atmosphere up to 80 km has a nearly similar composition and is called the homosphere. It’s uniform composition is due to
Gravitation of earth
Half of the atmospheric mass is contained _______ below
20000 ft
In jet standard atmosphere the lapse rate is
2*/1000
The rate of fall of the temperature with height is called
Lapse rate
In actual atmosphere the lapse rate could
Assume any value
Tropical tropopause extends from the equator to Lat 30_40 over India it is found at about _______ a over this there is inversion
16 -16.5 km
Inertial flow is
Anticyclonic in both hemispheres
Fog is ____ cloud on ground
B. Stratus
Frontal fog is more common with a
Warm front
The favourable pressure system for formation of fog is
Highs and cols
Thermal process / temperature distribution which favours of fog is
Inversion
Glazed ice is formed by freezing of ____ supercooled water droplets on aircraft airframe flying through cloud
Large
A WD originates over
Mediterranean, capstan and Black Sea
Induced lows develop to the ______ of WD (direction)
S
A jet stream cab be recognised by
Streaks of CI
Flying right angles to a jet stream with falling pressure you will experience
Wind from left
When abd where tropical jet stream occurs
In summers over SE Asia and central Africa
Surge and shear line are features of ____ monsoon
Vigorous
Peninsular discontinuity accuse along
Central peninsula
Peninsular discontinuity occurs during
Pre monsoon
Surge is also
Velocity convergence
In a depression the wind speed is
17-27 Kt
In a CS the wind speed is
34-47 kt
A monsoon depression slopes ___ with height
SW
Average life of a monsoon depression is
3-5 days
Monsoon depressions move faster over
Plains
For formation of CS sea surface temperature should be
26 -27* C
In extra tropical cyclone family there are 3-4 CS or depression. One to the ____ of the other
SW
In TRS the central pressure is about
1000-900 hPa
TRS develop over
Sea
TRS develop over ___ deg lat
5-15
In TRS pressure gradient is very steep up to a radius of
100 km
Extra tropical storm originates in
Polar front
Extra tropical generally moves in the direction (direction)
W to E
A tropical cyclone moves ___ in a day
300-500 hpa
A tropical CS has outer storm area is about
> 400 km
The up draughty in a CB cloud in India would normally be expected be the strongest in the thunderstorm of the
Pre monsoon season
On a flight around FL 390 from Calcutta to Delhi in a day in February you would expect to get a
Winds with strong headwind component and sometime cross components
Thunderstorms are most frequent in October/ nov over
Coastal Tamil Nadu
On a day in July very heavy rain is reposted from Himalaya foot hills but there is little or no rain else where in the Gangetic plains. Such situation would. E associated with
A break situation in Monsoon
First monsoon shower occurs over
Kerala
During the break in monsoon rainfall occurs over
Tamil Nadu and Himalayas
The winds at 45000 ft over Bangalore in July is
Strong easterly
Maximum freq of fog is in (region)
NW India
Thunderstorms frequency over west coast of India maximum in
August ( max in august sw monsoon )
In the month of July Calcutta reports surface visibility as 500 meters. You would infer that the poor visibility is due to
Heavy rain
Flying at FL 310 madras to Delhi on a day in January you would expect
Moderate westerly near Madras becoming very strong westerly near Delhi
Thick fog occur in January over UP abd adjoining areas in association with western disturbance
In the rear of active one which have given rain
The sun tropical jet stream passes over India during
October to may at around 200 MB level
The southwest monsoon normally sets in over Bombay around
The beginning of second week of June
When the axis the monsoon trough moves close to the foothills of Himalayas there is
Heavy rains in the hills
Inside an active thunderstorm you would except to have the strongest downdraft in
Heavy rain zone
The Chennai during early southwest monsoon season sea breeze can be expected when?
The monsoon current is weak
The majority of northwesters which affect dum dum in APRIL/may originate in the neighbourhood of
Chota Nagpur
Tropical cyclone most often strike the south Tamil Nadu coast in (months)
Sept/ oct
Where would you expect the max thunderstorm activity in august
West coast of India
Thunderstorms which occur in April/may in Bengal take place most frequently over Calcutta between (actual time)
1300 and 1700 hrs
In a mature tropical cyclone. Eye area is characterised by
Calm windchill little clouding and practically no rain
Cyclonic storm cross Tamil Nadu coast in (months)
Oct- Nov
Cyclonic storms form over Indian seas during
Pre monsoon & post monsoon
TRS occurs over Indian sea in Nm?
5-15* NM
In the bay of Bengal during the months of July, august, monsoon depression form over
Over Head bay
In a monsoon depression maximum weather occurs in
SW sector
Cyclonic storms are confirmed almost entirely to the
Tropical latitudes
