Download presentation
Presentation is loading. Please wait.
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
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.