L1 /   
12
CH3041
15 oC
thermosphere
THE ATMOSPHERE I
Atmosphere - a Stratified Vertical Structure
Homosphere <80km
- well mixed.
- turbulent mixing.
Heterosphere>80km
- not well mixed.
- gravitational settling
occurs,[atomic] O &
N low, H & He high
O3 heating
H2O cold barrier
O2 ® O heating
- most high E, short
l UV-C radiation is
absorbed here.
     l < 240 nm  
O2            ®        2O
Ionosphere