Atmosphere

Question 1

Atmosphere

Answer 1

AIR that surrounds the Earth and held together by Gravity

Question 2

Composition of the atmosphere

Answer 2

• 78% Nitrogen (N2)
• 21% Oxygen (O2)
• 1% other gases (0.95% Argon (Ar ), 0.05% Carbon Dioxide (CO2), Trace G)

Question 3

Layers of atmosphere

Answer 3

-Troposphere
-Stratosphere
-Mesosphere
-Thermosphere

Question 4

Troposphere

Answer 4

-Lowest layer in the atmosphere.
-Most weather phenomena take place in the troposphere
- It’s about 11 km thick, but it varies.
* Temperature decreases with height.
* The rate at which temperature decreases is generally about 2°C per 1000 ft.

Question 5

Tropopause

Answer 5

• The altitude where temperature no longer decreases with altitude
  – The air is STABLE. It resists further vertical movement
• So, the tropopause acts as a partial barrier which keeps most visible weather at and below it

Question 6

The tropopause fold

Answer 6

• Large surface temperature changes over short distances cause abrupt changes in the height of the tropopause.
• JET STREAMS are found here

Question 7

Stratosphere

Answer 7

• It extends from the tropopause to about 50 km AMSL
• Temperature increases with altitude, but not uniformly
• The temperature increase is caused by absorption of UV radiation by the ozone layer

– ozone layer is around 25 km AMSL
* Very STABLE and generally less convection.
* Used as cruising altitude for Commercial airliners