Atmospheric Structure Flashcards
Where is the Troposphere and how is it heated?
0-15km, so it is mainly heated by Earth’s surface, as rising warm air causes vertical mixing of gas
How much of the atmosphere’s mass and water vapour does the Troposphere contain?
80% mass and 99% vapour (most weather systems)
What happens at the Tropopause
Temperature reaches a minimum and stagnates before increasing in the Stratosphere
Where is the Stratosphere and how is it heated?
15-50km, it is heated from ozone blocking/absorbing UVA and UVB radiation energy, making it warm
How much of the atmosphere’s mass and water vapour does the Stratosphere contain?
Atmosphere: 19%
Water Vapour: almost none
What happens at the Stratopause?
Temperature reaches a maximum before decreasing in the Mesophere
Where is the Mesophere located and how is it heated?
50-58km, it is heated primarily by the Stratosphere, making it cold
What happens at the Mesopause?
It is the coldest place on Earth
Where is the Thermosphere and how is it heated?
58 to 500/1,000km, intense solar radiation ionises gas molecules, warming them to extreme temperatures, but the air wouldn’t feel hot as it’s in a vacuum
How are heat and temperature defined in the Thermosphere?
Heat: the amount of energy transmitted from molecules
Temperature: the energy of individual molecules
Where is the Exosphere and what are its conditions?
500/1,000 to ~100,000km. Temperature is essentially constant from this point upwards, with vacuum conditions and particles that are still bound by Earth’s gravity but no longer behave as gas. Only light particles are present and they slowly leak into space
