Chapter 1 – The Atmosphere
1. Which one of the following statements applies to the tropopause?
a. It is, by definition, an isothermal layer.
b. It indicates a strong temperature lapse rate.
c. It is, by definition, a temperature inversion.
d. It separates the troposphere from the stratosphere.
2. At a certain position, the temperature on the 300 hPa chart is -480C; according to the tropopause
chart, the tropopause is at FL 330. What is the most likely temperature at FL 350?
a. -54°C.
b. -50°C.
c. -56.5°C.
d. -58°C.
3. The tropopause is lower:
a. south of the equator than north of it.
b. over the equator than over the South Pole.
c. over the North Pole than over the equator.
d. in summer than winter in moderate latitudes.
4. What is the most likely temperature at the tropical tropopause?
a. -55°C.
b. -35°C.
c. -25°C.
d. -75°C.
5. Which statement is correct regarding the International Standard Atmosphere?
a. At MSL temperature is 15°C and the dcrease in temperature with height is 1°C per 100m.
b. At MSL temperature is 10°C and the dcrease in temperature with height is 1°C per 100m.
c. At MSL temperature is 1013.25hPa and the dcrease in temperature with height is 1°C per 100m.
d. At MSL temperature is 15°C and pressure is 1013.25hPa
6. The tropopause is a level at which:
a. water vapour content is greatest.
b. pressure remains constant.
c. vertical currents are strongest.
d. temperature ceases to fall with increasing height.
7. The 0°C isotherm is forecast to be at FL 50.
At what FL would you expect a temperature of -6°C?
a. FL 80.
b. FL 20.
c. FL 100.
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, d. FL 110.
8. How does temperature vary with increasing altitude in the ICAO standard atmosphere
below the tropopause?
a. Increases.
b. At first it increases and higher up it decreases.
c. Remains constant.
d. Decreases.
9. Which is true of the temperature at the tropopause?
a. It is higher in polar regions than in equatorial regions.
b. It is higher in equatorial regions than in Polar Regions.
c. It is highest in middle latitudes.
d. There is no significant difference with change of latitude.
10. What is the boundary layer between troposphere and stratosphere called?
a. Tropopause.
b. Ionosphere.
c. Stratosphere.
d. Atmosphere.
11. How would you characterise an air temperature of -15°C at the 700 hPa level over Western
Europe?
a. Low.
b. High.
c. Within +1-5°C of ISA.
d. 20°C below standard.
12. The temperature at FL 110 is -5°C: What will the temperature be at FL 50 if the ICAO
standard lapse rate is applied?
a. +3°C.
b. 0°C.
c. -3°C.
d. +7°C.
13. How does the height of the tropopause normally vary with latitude in the
northern hemisphere?
a. It remains constant throughout the year.
b. It decreases from south to north.
c. It remains constant from north to south.
d. It increases from south to north.
14. The temperature at FL 80 is +6°C. What will the temperature be at FL 130 if the ICAO
standard lapse rate is applied?
a. +2°C.
b. -4°C.
c. -6°C.
d. 0°C.
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Volume 9- Meteorology
,15. The lowest assumed temperature in the ICAO Standard Atmosphere is:
a. -273°C.
b. -44.7°C.
c. -100°C.
d. -56.5°C.
16. The troposphere is the:
a. part of the atmosphere below the tropopause.
b. part of the atmosphere above the stratosphere.
c. boundary between the mesosphere and thermosphere.
d. boundary between the stratosphere and the mesosphere.
17. How would you characterise an air temperature of -55°C at the 200 hPa level over Western
Europe?
a. Within +1-5°C of ISA.
b. High.
c. Low.
d. Very high.
18. The height and the temperature of the tropopause are respectively in the order of:
a. 8 km and -40°C over the equator.
b. 8 km and - 75°C over the poles.
c. 16 km and -40°C over the poles.
d. 16 km and -75°C over the equator.
19. What of the following is the most important constituent in the atmosphere from a weather stand-
point?
a. Nitrogen.
b. Oxygen.
c. Hydrogen.
d. Water vapour.
20. What is the vertical temperature lapse rate, up to 11 km, in the ICAO standard atmosphere?
a. 6.5°C per 1000m.
b. 4.5°C per 1000m.
c. 3°C per 1000m.
d. 2°C per 1000m.
21. An outside air temperature of -35°C is measured while cruising at FL 200. What is the temperature
deviation from the ISA at this level?
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Volume 9- Meteorology
, a. 10°C warmer than ISA.
b. 5°C warmer than ISA.
c. 5°C colder than ISA.
d. 10°C colder than ISA.
22. How would you characterise an air temperature of -30°C at the 300 hPa level over Western
Europe?
a. Within +/-5°C of ISA.
b. Low.
c. Very low.
d. High.
23. The rate of decrease of temperature with height per 100 m in the International Standard
Atmosphere is:
a. 0.65°C.
b. 1°C.
c. 0.5°C.
d. variable.
24. What is the approximate composition of the dry air by volume in the troposphere?
a. 50 % oxygen, 40 % nitrogen, and the rest other gases.
b. 21 % oxygen, 78 % nitrogen, and the rest other gases.
c. 10 % oxygen, 89 % nitrogen, and the rest other gases.
d. 88 % oxygen, 9 % nitrogen, and the rest other gases.
25. If you are flying at FL 300 in an air mass that is 15°C warmer than a standard atmosphere, what is
the outside temperature likely to be?
a. -15°C.
b. -30°C.
c. -45°C.
d. -60°C.
26. A temperature of +15°C is recorded at an altitude of 500 metres 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, 2500 metres above sea level?
a. +4°C.
b. 0°C.
c. -2°C.
d. +2°C.
27. The temperature at FL 140 is -12°C. What will the temperature be at FL 110 if the ICAO standard
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Volume 9- Meteorology
1. Which one of the following statements applies to the tropopause?
a. It is, by definition, an isothermal layer.
b. It indicates a strong temperature lapse rate.
c. It is, by definition, a temperature inversion.
d. It separates the troposphere from the stratosphere.
2. At a certain position, the temperature on the 300 hPa chart is -480C; according to the tropopause
chart, the tropopause is at FL 330. What is the most likely temperature at FL 350?
a. -54°C.
b. -50°C.
c. -56.5°C.
d. -58°C.
3. The tropopause is lower:
a. south of the equator than north of it.
b. over the equator than over the South Pole.
c. over the North Pole than over the equator.
d. in summer than winter in moderate latitudes.
4. What is the most likely temperature at the tropical tropopause?
a. -55°C.
b. -35°C.
c. -25°C.
d. -75°C.
5. Which statement is correct regarding the International Standard Atmosphere?
a. At MSL temperature is 15°C and the dcrease in temperature with height is 1°C per 100m.
b. At MSL temperature is 10°C and the dcrease in temperature with height is 1°C per 100m.
c. At MSL temperature is 1013.25hPa and the dcrease in temperature with height is 1°C per 100m.
d. At MSL temperature is 15°C and pressure is 1013.25hPa
6. The tropopause is a level at which:
a. water vapour content is greatest.
b. pressure remains constant.
c. vertical currents are strongest.
d. temperature ceases to fall with increasing height.
7. The 0°C isotherm is forecast to be at FL 50.
At what FL would you expect a temperature of -6°C?
a. FL 80.
b. FL 20.
c. FL 100.
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Volume 9- Meteorology
, d. FL 110.
8. How does temperature vary with increasing altitude in the ICAO standard atmosphere
below the tropopause?
a. Increases.
b. At first it increases and higher up it decreases.
c. Remains constant.
d. Decreases.
9. Which is true of the temperature at the tropopause?
a. It is higher in polar regions than in equatorial regions.
b. It is higher in equatorial regions than in Polar Regions.
c. It is highest in middle latitudes.
d. There is no significant difference with change of latitude.
10. What is the boundary layer between troposphere and stratosphere called?
a. Tropopause.
b. Ionosphere.
c. Stratosphere.
d. Atmosphere.
11. How would you characterise an air temperature of -15°C at the 700 hPa level over Western
Europe?
a. Low.
b. High.
c. Within +1-5°C of ISA.
d. 20°C below standard.
12. The temperature at FL 110 is -5°C: What will the temperature be at FL 50 if the ICAO
standard lapse rate is applied?
a. +3°C.
b. 0°C.
c. -3°C.
d. +7°C.
13. How does the height of the tropopause normally vary with latitude in the
northern hemisphere?
a. It remains constant throughout the year.
b. It decreases from south to north.
c. It remains constant from north to south.
d. It increases from south to north.
14. The temperature at FL 80 is +6°C. What will the temperature be at FL 130 if the ICAO
standard lapse rate is applied?
a. +2°C.
b. -4°C.
c. -6°C.
d. 0°C.
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Volume 9- Meteorology
,15. The lowest assumed temperature in the ICAO Standard Atmosphere is:
a. -273°C.
b. -44.7°C.
c. -100°C.
d. -56.5°C.
16. The troposphere is the:
a. part of the atmosphere below the tropopause.
b. part of the atmosphere above the stratosphere.
c. boundary between the mesosphere and thermosphere.
d. boundary between the stratosphere and the mesosphere.
17. How would you characterise an air temperature of -55°C at the 200 hPa level over Western
Europe?
a. Within +1-5°C of ISA.
b. High.
c. Low.
d. Very high.
18. The height and the temperature of the tropopause are respectively in the order of:
a. 8 km and -40°C over the equator.
b. 8 km and - 75°C over the poles.
c. 16 km and -40°C over the poles.
d. 16 km and -75°C over the equator.
19. What of the following is the most important constituent in the atmosphere from a weather stand-
point?
a. Nitrogen.
b. Oxygen.
c. Hydrogen.
d. Water vapour.
20. What is the vertical temperature lapse rate, up to 11 km, in the ICAO standard atmosphere?
a. 6.5°C per 1000m.
b. 4.5°C per 1000m.
c. 3°C per 1000m.
d. 2°C per 1000m.
21. An outside air temperature of -35°C is measured while cruising at FL 200. What is the temperature
deviation from the ISA at this level?
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Volume 9- Meteorology
, a. 10°C warmer than ISA.
b. 5°C warmer than ISA.
c. 5°C colder than ISA.
d. 10°C colder than ISA.
22. How would you characterise an air temperature of -30°C at the 300 hPa level over Western
Europe?
a. Within +/-5°C of ISA.
b. Low.
c. Very low.
d. High.
23. The rate of decrease of temperature with height per 100 m in the International Standard
Atmosphere is:
a. 0.65°C.
b. 1°C.
c. 0.5°C.
d. variable.
24. What is the approximate composition of the dry air by volume in the troposphere?
a. 50 % oxygen, 40 % nitrogen, and the rest other gases.
b. 21 % oxygen, 78 % nitrogen, and the rest other gases.
c. 10 % oxygen, 89 % nitrogen, and the rest other gases.
d. 88 % oxygen, 9 % nitrogen, and the rest other gases.
25. If you are flying at FL 300 in an air mass that is 15°C warmer than a standard atmosphere, what is
the outside temperature likely to be?
a. -15°C.
b. -30°C.
c. -45°C.
d. -60°C.
26. A temperature of +15°C is recorded at an altitude of 500 metres 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, 2500 metres above sea level?
a. +4°C.
b. 0°C.
c. -2°C.
d. +2°C.
27. The temperature at FL 140 is -12°C. What will the temperature be at FL 110 if the ICAO standard
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Volume 9- Meteorology
