1. The Atmosphere: Part 2: Radiative equilibrium
Composition / Structure
Radiative transfer
Vertical and latitudinal heat transport
Atmospheric circulation
Climate modeling
Suggested further reading:
Hartmann, Global Physical Climatology (Academic Press, 1994)

2. Planetary energy balance
Emission temperature

3. Atmospheric absorption

4. Principal atmospheric absorbers
• H2O: Bent triatomic, with permanent dipole moment and pure rotational bands as well as rotation-vibration transitions
• CO2 : No permanent dipole moment, so no pure rotational transitions, but temporary dipole during vibrational transitions
• O3: Like water, but also involved in photodissociation
• Other gases: CH4, N2O, CFCs
Clouds and aerosols

7. Top of atmosphere:
by definition

8. Top of atmosphere:
by definition
Bottom of atmosphere:

9. Top of atmosphere:
by definition
Bottom of atmosphere:

10. Top of atmosphere:
by definition
Bottom of atmosphere:

11. A more opaque atmosphere — a warmer surface
Ta = Te
T b = 21/4Te
Ts = 31/4Te

12. Top of atmosphere:
by definition
Bottom of atmosphere:

13. Atmospheric energy balance

14. Atmospheric energy balance

15. Radiative equilibrium profile

16. Full calculation of radiative equilibrium

17. Full calculation of radiative equilibrium
surface much too warm

18. Full calculation of radiative equilibrium
tropopause too cold
surface much too warm

19. Full calculation of radiative equilibrium
tropospheric lapse rate too large
tropopause too cold
surface much too warm

20. Full calculation of radiative equilibrium
stratosphere about right
tropospheric lapse rate too large
tropopause too cold
surface much too warm

21. Radiative equilibrium: role of various absorbers

22. Approach to equilibrium

23. Effect of clouds

24. Radiative effect of clouds
Altitude and thickness
Shape
Liquid water content
Ice/water
Particle sizes