Atmosphere

Question 1

What is the atmosphere mainly made of?

Answer 1

Nitrogen 78.09%
Oxygen 20.95%
Argon 0.93%
Carbon dioxide 0.03%

Question 2

What else makes up the atmosphere?

Answer 2

Hydrogen
Ozone - absorbs harmful radiation from the sun
Water vapour - close to the ground
Carbon
Salt crystals - needed to initiate condensation

Question 3

Lapse rate

Answer 3

Change of height and temperature

Question 4

Positive/normal lapse rate

Answer 4

Height increases, temp decreases

Question 5

Negative lapse rate / temp inversion

Answer 5

Height increases, temp increases

Question 6

Isothermal layer

Answer 6

Temp remains constant with change in height

Question 7

What are the layers in the atmosphere?

Answer 7

Troposphere
Stratosphere
Mesosphere
Thermosphere

Question 8

Troposphere

Answer 8

Height increases, temp decreases
Almost all water vapour located
3/4 total mass of atmosphere

Question 9

Where does aviation occur?

Answer 9

Mostly troposphere and also low stratosphere

Question 10

Tropopause

Answer 10

Temp becomes constant value
Higher over warmer air, lower over colder air
11km / 36,000ft

Question 11

Height at Polar TP

Answer 11

25,000ft / 7.5km

Question 12

Tropical TP (equator)

Answer 12

55,000ft / 17km

Question 13

Stratosphere

Answer 13

Lower part: isothermal, 11km - 15km
Upper part: height increases, temp increases, due to radiation from sun absorbed by ozone, 15km (approx.49,000ft) - 50km (approx.164,000ft)

Question 14

What is the temp at the Stratopause?

Answer 14

approx. 0 degrees celsius

Question 15

Mesosphere

Answer 15

Height increases, temp decreases

Question 16

Temp at Mesopause

Answer 16

approx. -90 degrees celsius

Question 17

Thermosphere

Answer 17

Height increases, temp increases
Ionosphere: 700km (approx. 2,000,000ft), free electrons released due to sun’s rays
Exosphere: upper part

Question 18

ISA

Answer 18

International Standard Atmosphere

- worldwide reference