Which one of the following statements applies to the tropopause?
It is, by definition, an isothermal layer.
It indicates a strong temperature lapse rate.
It is, by definition, a temperature inversion.
It separates the troposphere from the stratosphere.
At a certain position, the temperature on the 300 hPa chart is -48°C; according to the tropopause chart, the tropopause is at FL330. What is the most likely temperature at FL350?
-54°C
-50°C
-56.5°C
-58°C
The tropopause is lower...
south of the equator than north of it.
over the equator than over the South Pole.
over the North Pole than over the equator.
in summer than winter in moderate latitudes.
What is the most likely temperature at the tropical tropopause?
-55°C
-35°C
-25°C
-75°C
Which statement is correct regarding the International Standard Atmosphere?
At MSL temperature is 15°C and the decrease in temperature with height is 1°C per 100m.
At MSL temperature is 10°C and the decrease in temperature with height is 1°C per 100m.
At MSL pressure is 1013.25 hPa and the decrease of temperature with height is 1°C per 100m.
At MSL temperature is 15°C and pressure is 1013.25hPa.
The tropopause is a level at which...
water vapour content is greatest.
pressure remains constant.
vertical currents are strongest.
temperature ceases to fall with increasing height.
The 0°C isotherm is forecast to be at FL050. At what FL would you expect a temperature of -6°C?
FL080
FL020
FL100
FL110
How does temperature vary with increasing altitude in the ICAO standard atmosphere below the tropopause?
It increases.
At first it increases and higher up it decreases.
It remains constant.
It decreases.
Which is true of the temperature at the tropopause?
It is higher in polar regions than in equatorial regions.
It is higher in equatorial regions than in polar regions.
It is highest in middle latitudes.
There is no significant difference with change of latitude.
What is the boundary layer between troposphere and stratosphere called?
Tropopause
Ionosphere
Stratosphere
Atmosphere
How would you characterise an air temperature of -15°C at the 700hPa level over Western Europe?
Low
High
Within +/-5°C of ISA
20°C below standard
The temperature at FL110 is -5°C. What will the temperature be at FL050 if the ICAO standard lapse rate is applied?
+3°C
0°C
-3°C
+7°C
How does the height of the tropopause normally vary with latitude in the northern hemisphere?
It remains constant throughout the year.
It decreases from south to north.
It remains constant from north to south.
It increases from south to north.
The temperature at FL080 is +6°C. What will the temperature be at FL130 if the ICAO standard lapse rate is applied?
+2°C
-4°C
-6°C
What is the lowest assumed temperature in the ICAO Standard Atmosphere?
-273°C
-44.7°C
-100°C
The troposphere is the...
part of the atmosphere below the tropopause.
part of the atmosphere above the stratosphere.
boundary between the mesosphere and thermosphere.
boundary between the stratosphere and the mesosphere.
How would you characterise an air temperature of -55°C at the 200hPa level over Western Europe?
Very high
The height and the temperature of the tropopause are respectively in the order of...
8 km and -40°C over the equator.
8 km and - 75°C over the poles.
16 km and -40°C over the poles.
16 km and -75°C over the equator.
What of the following is the most important constituent in the atmosphere from a weather stand-point?
Nitrogen
Oxygen
Hydrogen
Water vapour
What is the vertical temperature lapse rate, up to 11km, in the ICAO standard atmosphere?
6.5°C per 1000m
4.5°C per 1000m
3°C per 1000m
2°C per 1000m
An outside air temperature of -35°C is measured while cruising at FL200. What is the temperature deviation from the ISA at this level?
10°C warmer than ISA
5°C warmer than ISA
5°C colder than ISA
10°C colder than ISA
How would you characterise an air temperature of -30°C at the 300hPa level over Western Europe?
Very low
What is the rate of decrease of temperature with height per 100m in the International Standard Atmosphere?
0.65°C
1°C
0.5°C
Variable
What is the approximate composition of the dry air by volume in the troposphere?
50% oxygen, 40% nitrogen, and the rest other gasses
21% oxygen, 78% nitrogen, and the rest other gasses
10% oxygen, 89% nitrogen, and the rest other gasses
88% oxygen, 9% nitrogen, and the rest other gasses
If you are flying at FL300 in an air mass that is 15°C warmer than a standard atmosphere, what is the outside temperature likely to be?
-15°C
-30°C
-45°C
-60°C
A temperature of +15°C is recorded at an altitude of 500m above sea level. If the vertical temperature gradient is that of a standard atmosphere, what will the temperature be at the summit of a mountain, 2500m above sea level?
+4°C
-2°C
The temperature at FL140 is -12°C. What will the temperature be at FL110 if the ICAO standard lapse rate is applied?
-18°C
-9°C
If you are flying at FL120 and the outside temperature is -2°C, at what altitude will the "freezing level" be?
FL150
FL090
FL130
The troposphere...
reaches the same height at all latitudes.
has a greater vertical extent above the equator than above the poles.
contains all oxygen of the stratosphere.
is the separation layer between the stratosphere and atmosphere.
The thickness of the troposphere varies with...
rotation of the Earth.
the wind.
latitude.
longitude.
What, approximately, is the average height of the tropopause over the equator?
16km
8km
11km
40km
Going from the equator to the North Pole, the altitude of the tropopause...
decreases and its temperature increases.
increases and its temperature increases.
increases and its temperature decreases.
decreases and its temperature decreases.
What is the temperature at 10,000ft in the International Standard Atmosphere?
-20°C
-5°C
What, approximately, is the average height of the tropopause at 50°N?
14km
In the lower part of the stratosphere, the temperature...
increases with altitude.
increases at first and decreases afterward.
is almost constant.
decreases with altitude.
Which layer of the atmosphere contains more than 90% of all water vapour?
Troposphere
Lower stratosphere
Upper stratosphere
In the mid-latitudes the stratosphere extends on an average from...
85 to more than 200km.
11 to 50km.
0 to 11km.
50 to 85km.
