1. Oxygen: Stratosphere, Mesosphere and Thermosphere Part-3
Chemical Rate Equations
Ozone Density vs. Altitude
Stratospheric Heating
Thermal Conductivity
Thermospheric Structure
Temperature Structure on other planets

2. Rate Equations for Oxygen Chemistry

3. Introduce Ozone

4. Ozone continued

5. Dependence on z Remember: J2(z) = J2o exp[ -2(z)/] where  = cos
2(z) = abs o n2 dz
n2(z)  0.21 nM
nM(z) = nM(0) exp(-z/H)
in mixed region
J3(z) = J3o exp[ -3(z)/]
For 3(z) need n3(z)
which we are solving for.

6. T High z J2/J3 =constant ~10-7 Low z J2/J3 --> 0 J2 80 J3 40 10-2/s
mesopause 80 n3
… stratopause
Tropopaus 20 T
n3 , T

7. Densities of O2,O3 and O C+H
High z
n1  1/n21/2
n3  n23/2
Log10n(mol/cc)
To get right: need some diffusive separation in the upper regions
At night: J2(z) and J3(z) --> 0
‘slow’ reactions become important

8. Temperature vs. Altitude Earth’s Atmosphere
Stratospheric Heating peak and Ozone Peak related
J3(z) = J3o exp[ -3(z)/]
dT/dt  h3 J3(z) n3(z)

9. Summary

10. Thermosphere + IonosphereZ
130km
80km
EUV
I R
Thermal
conduction
mesopause

11. Fs(z) Dz
FT + DF z FT

12. Thermosphere Continued

13. Thermosphere T Structure
Tm is where the heat conducted
downward is radiated to space
Relation to our old Te?

14. Thermosphere Structure (Cont)

15. Integral for thermosphere model
y(x) = ox { [1-exp(-x’)]/x’} dx’
x  (z); y  T7/4

16. Temperature vs. Altitude Earth’s Atmosphere
Rise in T in Thermosphere
due to EUV Absorption
and Thermal Conduction
to Mesopause
These are averages
Tropopause is higher and hotter
Near equator ~16-18km and ~ 10km near poles
Drives high altitude horizontal flow
Jets ~10km to be close to stratosphere
and avoid turbulence

17. A result of Horizontal Transport Ozone column density in ppm
Tropopause higher near equator and lower in T
Drives upper atmospheric flows
Will treat horizontal transport soon

18. Noctilucent Clouds (night shining clouds, ~85km, ice grains) (polar mesospheric clouds) over a lake in northern Sweden Possibly produced by climate change and space shuttle exhaust
Polar Stratospheric (nacreous)Clouds
~15-25km: ice, nitric and sulfuric acids
Implicated in ozone holes

19. Polar Stratospheric (nacreous)Clouds
~15-25km: ice, nitric and sulfuric acids
Implicated in ozone holes

20. Thermosphere T depends on Solar Activity
Earth’s Thermal Structure dePL
Thermosphere T depends on Solar Activity

21. CO2 even at high altitudes --> cooling Slow Rotation
Venus Atmosphere dePL
Cloud Tops --> Te
CO2 even at high altitudes --> cooling
Slow Rotation
1 year = 2 days
(retrograde due to thickatmosphere and tidal forces?)

22. Dust absorbs h and changes the lapse rate
Mars Atmosphere dePL
Te at Surface
Dust absorbs h and changes the lapse rate
Thermosphere strongly dependent on solar activity

23. Photo-chemistry Venus + Mars
CO2 + hn ® CO + O (1)
CO+O+M ® CO2 + M (2)
(2) is very slow at Mars (density of M
Is very small):
Expect considerable CO, especially so
as free O oxidize surface (iron oxide)
But there is a small amount of H2O
H2O + hn ® OH + H (3)
CO + OH ® CO2 + H (4)
On Venus CO --> CO2 may be aided by
sulfur + chlorine species

24. Titan’s Atmosphere dePL
Stratosphere/ mesosphere due to
absorption in hydrocarbon haze
CH4 + h -> CH3 +H(CHf +H2)
React to form CnHmand H2 escapes.
Thermosphere subject to particles
from Saturn’s magnetosphere

25. Adiabatic lapse rate down to liquid metal hydrogen
Giant Planets dePL
Internal heat sources
Adiabatic lapse rate down to liquid metal hydrogen
Jupiter has evidence of a stratosphere and a mesosphere

26. Atmosphere Thermal Structure: Summary
Typically
troposphere (Lower, Convective)
Mesosphere [ Stratosphere ] (Middle, Radiative)
Thermosphere (Upper, Conductive)
Exosphere (Escape)
Venus
Temperature Lapse, g £ Gd
Tropopause at cloud layer (~ 70 km)
Te ~ Top of cloud layer
Thermosphere (Cryosphere)
Td ~ 300 km (CO2 at high altitudes)
Tn ~ 100 km (Slow rotation 1yr » 2 days)
Mars
Temperature Lapse g £ Gd
(Strong Day / Night Variations: Dust g << Gd
Mesosphere T < Te (CO2 cooling)
Thermosphere like Mesosphere
(Strongly affect by solar activity)
Titan
Temperature Lapse g ~ Gd
Stratosphere (Haze Layer)
Mesosphere (Cooler to space)
Thermosphere (Solar UV + Energetic Particles
from Magnetosphere Cooled by
HCN, Slow Rotations)
Grant Planets
Internal heat source comparable to solar
Tropopause ~ 0.1 bar, g ~ Gd,
Temperature + pressure increase to about 2M bar so phase
change to a liquid (metallic) state (4x104 km) and a metallic
core (3x104 K) (1x104 km) (Jupiter)
Mesosphere (stratosphere) £ bar Hydrocarbon coolants
Thermosphere (Solar EUV)

27. Earth’s thermal structure Rate equations Oxygen reactions Ozone layer
#3 Summary
Things you should know
Earth’s thermal structure
Rate equations
Oxygen reactions
Ozone layer
Stratosphere
Mesosphere
Thermosphere
Thermal conductivity
Heat flux