The Atmosphere

Question 1

Define the term: Troposphere

Answer 1

• Lowest layer of the atmosphere
• Averages 36,090ft
• Temperature and pressure decrease with height
• Has almost all aerosols and water vapour

Question 2

Define the term: Tropopause

Answer 2

• Boundary between the troposphere/stratosphere
• Higher over the equator, lower over the poles
• Higher in summer, lower in winter
• Higher during the day, lower at night

Question 3

Define the term: Stratosphere

Answer 3

• Air is stable
• Usually devoid of cloud
• Is where the Ozone is
• Temperature slightly increases with height or is isothermal

Question 4

Explain how surface pressure within the tropospheric column affects the height of the tropopause.

Answer 4

• Pressure increase = height of the tropopause increase
• Pressure decrease = height of the tropopause decrease

Question 5

Explain how temperature within the tropospheric column affects the height of the tropopause.

Answer 5

Temperature increase = height of tropopause increase
Temperature decrease = height of tropopause decrease

Question 6

State the average tropopause height and temperature at the equator.

Answer 6

• 56,000ft
• Minus 75 degrees Celsius

Question 7

State the average tropopause height and temperature at the poles.

Answer 7

• 26,000ft
• Minus 45 degrees Celsius

Question 8

State the average tropopause height and temperatures at the mid latitudes.

Answer 8

• 36,090ft
• Minus 56.5 degrees Celsius

Question 9

Explain the sources of aerosols within the atmosphere.

Answer 9

• Tiny solid particles
• Salt from ocean spray (most common in NZ)
• Smoke and dust
• Volcanic ash

Question 10

Explain the effects of aerosols within the atmosphere.

Answer 10

• Allow vapour to change to liquid or solid.
• Known as condensation nuclei or freezing nuclei
• Reduce visibility if too many

Question 11

Explain the importance of aerosols within the atmosphere

Answer 11

• Cloud would not form without them
• Absence of them increases danger of aircraft icing (aircraft then becomes the condensation nuclei)
• Air becomes super saturated with no aerosols around
• Not many at the poles so air can reach 400% relative humidity

Question 12

Describe the effect of increasing height and/or latitude on water vapour and aerosol content within the atmosphere.

Answer 12

• Source of water vapour and aerosols is the surface
• Both decrease in quantity with height
• Hardly any of both above the troposphere

Question 13

Explain the effects on temperature within the atmosphere due to water vapour.

Answer 13

• Absorbs both solar and terrestrial radiation
• Warms the atmosphere

Question 14

Explain the effects on temperature within the atmosphere due to carbon dioxide.

Answer 14

• Absorbs terrestrial radiation
• Warms the atmosphere
• Does not absorb solar radiation

Question 15

Explains the effects on temperature within the atmosphere due to Ozone.

Answer 15

• Absorbs ultraviolet light
• Warms the area its located in, the stratosphere
• Creates an inversion acting as a weather lid on the troposphere.

Question 16

With respect to the tropopause, describe the idealised global tropopause detailing approximate altitudes and the position of jet-streams.

Answer 16

• Sub tropical jet stream = 200hPa level 30degreesN/S
• 38,000 ft
• Polar Jet stream = 300-500hPa Level 60degreesN/S
• 30,000 - 18,000ft

Question 17

With respect to the tropopause, explain why the height of the tropopause varies with latitude and season.

Answer 17

• Changes due to temperature of troposphere or stratosphere
• Warming the troposphere increases its height
• Cooling the stratosphere increases its height

Question 18

Explain why the stratosphere is generally devoid of cloud and turbulence.

Answer 18

• Inversion/isothermal created due to the Ozone - this acts as a lid as the colder air below cannot rise any further.