ATSC 113 Common practice test Questions and Answers;
verified and accurate 2025
Armstrong altitude - correct answer Above 62000 ft, boiling T decreases to
where your bodily fluid starts boils, need a pressurized suit.
Density Altitude - correct answer Pressure altitude corrected for different
temperature, lower density leads to longer runway for take-off and landing,
slower climbing, not being able to climb as high.
Convective Boundary Layer - correct answer Air rises due to heating from
sun. Diameter similar to depth, cumulus cloud may form w/ enough
moisture. If these cumulus aligned in a row -> cloud streets.
Anabatic winds - correct answer Air movement when thermals follow the
slope and rise vertically above ridge top. If humid enough -> anabatic
cumulus.
Sea level pressure/ mean sea level pressure - correct answer Surface
pressure if it was at sea level.
Ridges & Troughs of Pressure pattern - correct answer Ridges: rel. High P
that extends from high P centres.
Troughs: lines of propagation of low P.
High P system - correct answer aka anticyclone, associated w/ dry, clear
skies, less precipitation
,Flat light - correct answer when high clouds diffuse light & snow surface
has no definition (low P approaching)
P-level map - correct answer Sea leve = 100kpa
1500m = 85.0kpa
3000m = 70.0kpa
Dry vs wet adiabatic condition - correct answer Dry: T decreases at
10C/km (9.8), <80% rel. Humidity, in the daytime during spring/ afternoon
on sunny winter days.
Wet: T decrease slower 6C/km, >80% rel. Humidty.
Stable conditions - correct answer Temperature decreases more slowly or
even increases w/ height.
Inversion typically within valley overnight/ winter morning/ arctic air
outbreak.
At mid/upper elevation, very stable T common during frontal passage (no
vertical T interpolation needed).
Factors affecting heating/cooling - correct answer Sun angle: Daylight hr
and sun intensity are lower in winter -> heating adjustment for daytime high
T is small whereas spring is much larger
Cloud cover: cloud cover reduces heating for daytime high T, cloud also
absorbs energy from ground & radiates back to ground (smaller cooling at
night).
Wind speed: during day, wind can reduce solar radiative heating by mixing
with cooler air just above or reduce radiative cooling effect.
,Snow at the bottom is close to __ - correct answer 0C due to heating from
ground (colder top, warmer bot), water vapor moves from warm to cold T
(speed related to T dif.) -> travels up.
Faceted crystals - correct answer Produced w/ strong T gradient
(>10C/m), water vapor moves quickly & crystal growth fast.
Clear, calm night for colder continental climate.
Lot of space btw snow crystals (weakly bonded, unstable) -> snow crystals
near bot very large & angular -> depth hoar.
League of Legends Joke 2 - correct answer Q: Who beats Orianna mid
lane?
A: Ochrisbrown.
Rounded Crystals - correct answer Weak T gradient (<10C/m), water
vapor moves slowly, crystal growth is slow. Cloudy/windy night time.
Happens in warmer, wetter, coastal climate, Tightly packed crystals.
Surface hoar/frost - correct answer Frozen dew produced by deposition
onto snow surface when air T falls below frost point T.
May lead to avalanche as it is feathery and delicate.
Once buried by snowfall, it acts as a weak later.
Being buried for weeks -> persistent weak layer.
Sun (sublimation), strong wind (sublimation/mechanical),
melting/refreezing, rain destroy surface hoar.
What is needed for hoar frost to form? - correct answer Clear night, snow
surface T decreases gently due to radiation.
, Calm winds allow delivery of water vapor
Strong T inversion
Size depends on length of the condition
Shady north-facing slope allows for more growth
Trees or rocks inhibit formation due to radiative warming
Hand hardness test - correct answer Tests density & cohesiveness of the
layer by applying light pressure to snowpack layer
Fist (softest), 4 fingers, 1 finger, pencil, knife (hardest)
Snow pack layer types - correct answer 1. Weakly-bonded: Undergone
faceting, lower density, less cohesive. Surface hoar, newly-fallen snow
(however, will start settling). Fist/4 finger.
2. Strongly bonded: Old stellar dendrites that are now rounded crystals,
more dense/hard. New-fallen snow w/ higher density (warm & windy), or
wind slabs. 4 finger if upper 1-finger if mid/lower.
3. Crust Layers: Rain-on-snow event followed by bellow freezing T, rain-
saturated snow freezes->rain crusts. Or above-freezing T-> refreezing->
melt/freeze crust. Or sun crust (radiative heating, common on southerly
face in N.Hem). Crust blocks water vapor within snowpack causing weak
facet layer.
Insult Joke - correct answer Kid 1: "Hey, I bet you're still a virgin."
Kid 2: "Yeah, I was a virgin until last night ."
Kid 1: "As if."
Kid 2: "Yeah, just ask your sister."
Kid 1: "I don't have a sister."
Kid 2: "You will in about nine months."
verified and accurate 2025
Armstrong altitude - correct answer Above 62000 ft, boiling T decreases to
where your bodily fluid starts boils, need a pressurized suit.
Density Altitude - correct answer Pressure altitude corrected for different
temperature, lower density leads to longer runway for take-off and landing,
slower climbing, not being able to climb as high.
Convective Boundary Layer - correct answer Air rises due to heating from
sun. Diameter similar to depth, cumulus cloud may form w/ enough
moisture. If these cumulus aligned in a row -> cloud streets.
Anabatic winds - correct answer Air movement when thermals follow the
slope and rise vertically above ridge top. If humid enough -> anabatic
cumulus.
Sea level pressure/ mean sea level pressure - correct answer Surface
pressure if it was at sea level.
Ridges & Troughs of Pressure pattern - correct answer Ridges: rel. High P
that extends from high P centres.
Troughs: lines of propagation of low P.
High P system - correct answer aka anticyclone, associated w/ dry, clear
skies, less precipitation
,Flat light - correct answer when high clouds diffuse light & snow surface
has no definition (low P approaching)
P-level map - correct answer Sea leve = 100kpa
1500m = 85.0kpa
3000m = 70.0kpa
Dry vs wet adiabatic condition - correct answer Dry: T decreases at
10C/km (9.8), <80% rel. Humidity, in the daytime during spring/ afternoon
on sunny winter days.
Wet: T decrease slower 6C/km, >80% rel. Humidty.
Stable conditions - correct answer Temperature decreases more slowly or
even increases w/ height.
Inversion typically within valley overnight/ winter morning/ arctic air
outbreak.
At mid/upper elevation, very stable T common during frontal passage (no
vertical T interpolation needed).
Factors affecting heating/cooling - correct answer Sun angle: Daylight hr
and sun intensity are lower in winter -> heating adjustment for daytime high
T is small whereas spring is much larger
Cloud cover: cloud cover reduces heating for daytime high T, cloud also
absorbs energy from ground & radiates back to ground (smaller cooling at
night).
Wind speed: during day, wind can reduce solar radiative heating by mixing
with cooler air just above or reduce radiative cooling effect.
,Snow at the bottom is close to __ - correct answer 0C due to heating from
ground (colder top, warmer bot), water vapor moves from warm to cold T
(speed related to T dif.) -> travels up.
Faceted crystals - correct answer Produced w/ strong T gradient
(>10C/m), water vapor moves quickly & crystal growth fast.
Clear, calm night for colder continental climate.
Lot of space btw snow crystals (weakly bonded, unstable) -> snow crystals
near bot very large & angular -> depth hoar.
League of Legends Joke 2 - correct answer Q: Who beats Orianna mid
lane?
A: Ochrisbrown.
Rounded Crystals - correct answer Weak T gradient (<10C/m), water
vapor moves slowly, crystal growth is slow. Cloudy/windy night time.
Happens in warmer, wetter, coastal climate, Tightly packed crystals.
Surface hoar/frost - correct answer Frozen dew produced by deposition
onto snow surface when air T falls below frost point T.
May lead to avalanche as it is feathery and delicate.
Once buried by snowfall, it acts as a weak later.
Being buried for weeks -> persistent weak layer.
Sun (sublimation), strong wind (sublimation/mechanical),
melting/refreezing, rain destroy surface hoar.
What is needed for hoar frost to form? - correct answer Clear night, snow
surface T decreases gently due to radiation.
, Calm winds allow delivery of water vapor
Strong T inversion
Size depends on length of the condition
Shady north-facing slope allows for more growth
Trees or rocks inhibit formation due to radiative warming
Hand hardness test - correct answer Tests density & cohesiveness of the
layer by applying light pressure to snowpack layer
Fist (softest), 4 fingers, 1 finger, pencil, knife (hardest)
Snow pack layer types - correct answer 1. Weakly-bonded: Undergone
faceting, lower density, less cohesive. Surface hoar, newly-fallen snow
(however, will start settling). Fist/4 finger.
2. Strongly bonded: Old stellar dendrites that are now rounded crystals,
more dense/hard. New-fallen snow w/ higher density (warm & windy), or
wind slabs. 4 finger if upper 1-finger if mid/lower.
3. Crust Layers: Rain-on-snow event followed by bellow freezing T, rain-
saturated snow freezes->rain crusts. Or above-freezing T-> refreezing->
melt/freeze crust. Or sun crust (radiative heating, common on southerly
face in N.Hem). Crust blocks water vapor within snowpack causing weak
facet layer.
Insult Joke - correct answer Kid 1: "Hey, I bet you're still a virgin."
Kid 2: "Yeah, I was a virgin until last night ."
Kid 1: "As if."
Kid 2: "Yeah, just ask your sister."
Kid 1: "I don't have a sister."
Kid 2: "You will in about nine months."
