Met1 Flashcards
Troposphere is from surface to ??????
36,000ft
Tropopause is at 36,000ft and sits on top of the???????
Troposphere
Tropopause contains what percentage of total air mass
75%
The tropopause is part of the ????
Stratosphere
Temperatures does what with height
Reduces 1.9deg per 1000ft until 36,000
Cumulonimbus is shortened to
CB
An anvile cloud could be described as
Cumulonimbus
Nimbus means…
Rain bearing
Troposphere is heated by
The earth’s surface radiating up
Nitrogen is what percentage of the atmosphere
78%
What gas makes up 21% of the atmosphere?
Oxygen
Water vapor is what percent of the troposphere?
4% volume
Where in the troposphere is the water vapour found
(Percentage and height)
Half of it’s mass is below 1.5km
99% of water vapour is contained within the…
Troposphere
What happens to the capacity to hold water vapour with varying air temperatures?
Warmer air has grater capacity to hold water vapour
Tropopause is at what altitude ISA
36,090ft
-56.5°c
Equatorial tropopause is
16 - 18 km high
Due to heat
(But colder as it’s higher)
Polar tropopause is
8 - 10 km high
Due to cold
(But warmer as it’s lower)
Tropopause varies during the year. How?
Winter - is lower (16 km equitorial)
Summer is high (18 km equitorial)
Latitude tells us where we are on what axis?
Up / down
N / S
(Pole - equator - pole)
Lat - ladder
Longitude tells us where we are on what axis?
East / West
Greenwich
SIGWX chart gives us spot heights of what?
Tropopause
H - is the highest
L - is the lowest
SIGWX chart have big black lines, what do they represent?
Jetstreams have speed indicated on them
SIGWX has a key
Use the key
SIGWX chart may have a XXX on an altitude range, what does it mean?
Beyond the scope of the chart
What is the altitude range of the stratosphere
36,000ft - 65,600ft
11km - 20km
Ozone sits within which part of the atmosphere
stratosphere
Ozone layer is present in what altitude range?
20 - 30km
What two things makes the stratosphere a generally good place to fly?
> Clouds rare
Above hazards of troposphere (eg CBs
Turbulence still possible
How much of the OZONE is contained within the stratosphere?
90%
Which part of the atmosphere absorbs short-wave UV radiation?
OZONE in the stratosphere
OZONE has which properties
Extremely corrosive gas
What is responsible for temperature increase on the stratosphere?
OZONE
Respiratory problems can be caused by?
OZONE
ICAO stands for?
International
Civil
Aviation
Organisation
ISA temperature
+15 Deg C
Mean sea level
Lapse rate
-1.98 Deg per 1000 ft
ISA pressure
1013.25
29.92 InHg
Best buddy with density
ISA density
1.225 Kg/m3
Best buddy with pressure
-56.5°c constant from and to which altitudes?
11km to 20km
Define:
ISA deviation
Difference between ISA and reality
Change in 1 hPa corresponds to how many feet?
30feet (at sea level)
Is pressure lapse rate constant as you climb
No, 30ft at sea level.
Pressure lapse rate decreases with height
300hPa is what FL
FL300
500hPa is what FL
FL180
At what altitude is ISA Density approximately
50% compare to MSL
At 22,000 ft, ISA Density is approximately
50% compare to MSL
At what altitude is ISA Density approximately
25% compare to MSL
At 40,000 ft, ISA Density is approximately
25% compare to MSL
ICAO is based where?
Montreal
What is ICAO for?
standarisation
WMO stands for
World meteorological organisation
In 1982 ICAO and WMO came up with what?
World Area Forecast System
VAAC stands for
Volcanic Ash Advisory Centre
TAF stands for
Terminal Area Forecast
World area forecast centres provide what kind of forecasts
Upper-air gridded forecasts
Who issues significant weather charts
World area forecast centres
How often are significant weather charts updated
6 - 9 hours
How often are TAF’s produced?
3 or 6 hours.
What reports of airfield conditions about snow/slush/ice
SNOWTAM
Valid up to 8hours
The name for an interim METAR is
SPECI
How often are METARs updated
30 - 60 mins
TRS stands for
Tropical revolving storm
(Usually over water)
MWO stands for
Meteorological watch office
SIGMET is released how often?
4 - 6 hours
TCA stands for
Tropical cyclone advisors
SEV MTW stands for
Severe mountain wave
STNR INTSF stands for
Stationary and intensifying
SIGMET shall not exceed how many hours?
4 hours
SIGMET is short for
Significant meteoroligican information
SIGMET would cover what types of weather
Thunderstorms (TS)
Tropical Cyclone (TC)
Severe turbulence
Severe icing (inc SEV due FZRA)
Severe mountain waves
Heavy Sand or Dust storm (SS & DS)
Volcanic Ash and radioactive cloud (VA & RDOACT)
METAR is released how often?
30 or 60mins
In a METAR:
VC means
Vicinity
8 - 16 km from the aerodrome
Runway numbering is true or magnetic?
Magnetic
ATIS, ATC use true or magnetic north?
Magnetic
METAR, TAF, SPECI, TREND use true or magnetic north
True
What is the name for a non-routine surface observation with the same as a METAR
SPECI
METAR wind is a mean over what period
10min mean
FEW is how many octas
1 - 2
Cloud base
SCT is how many octas
3 - 4
Cloud base
BKN is how many octas
5 - 7
Ceiling
OVC is how many octas
8
Ceiling
BECMG means?
conditions becoming between set time – permanent change.
TEMPO mean?
Temporary fluctuations in conditions, lasting less than one hour
in each instance, in aggregate, covering less than half the TEMPO period.
TAF:
FM means?
certain condition will prevail at specific time (similar to a BECMG)
TAF:
PROB means?
indicates the probability that a certain change or value will occur.
TAF may provide MAX and MIN temperature forecast. How is maximum and minimum notated on the TAF?
TX - max
TN - min
Define CAVOK
Visibility greater or equal to 10 km and the lowest visibility is not reported, no cumulonimbus or towering cumulus, no cloud below 5000 ft or highest minimum sector altitude (MSA)( whichever is the greater) and no weather significant to aviation.
What type of forecast would you pick up in flight?
VOLMET - broadcast on a schedule
Which in-flight report is played on a loop with 5 mins for each station?
VOLMET
Hadley, ferrel and polar are examples of what?
Cells?
In the ISA between 11 km and 20 km altitude the temperature lapse rate could be described as what
Isothermal
How would you describe the change in temperature in the stratosphere
Increases