The dynamics of planetary atmospheres

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The dynamics of planetary atmospheres
Theoretical concept is formulated in
the Geophysical Fluid Dynamics the dynamics of
stratified fluid on a rotating sphere
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Hadley cell circulation
easterly (passat) flow
Solar flux
tidal buldge
convective flow
westerly jet
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Primitive equationsfluid on a rotating sphere
momentum
energy
continuity
eqn. of state
modifications
absolute vorticity
Boussinesq approximation
everywhere but gravity
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Spherical coordinate system
z, w
y, v
x, u
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Useful numbers
Coriolis parameter
?-plane approximation
Rossby parameter
Rossby number
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Adjustments
equation of horizontal motion
geostrophic approximaton
hydrostatic approximation
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Ro ltlt 1 thermal wind equation
Opposite case Ro gtgt 1
cyclostrophic approximation
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Wave motion in the atmosphere

• Elasticity sound
• Buoyancy gravity waves
• Coriolis force inertial waves

Planetary-scale forced oscillations of any type
are called tides
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acoustic waves
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gravity waves
?-potential temperature
Brunt-Vajsala frequency
For non-vertically propagating waves,
Group velocity
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Rossby waves
Search for the solution in form
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Eliminating P and use incompressibility,
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Solsticial circulation on Mars
Solar flux
thermal tide
westerly jet
Rossby waves
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Water vapor column Ls 92?, North hemisphere
kg/m2
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Water vapor column Ls 113?, North hemisphere
kg/m2
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Water vapor column Ls 143?, North hemisphere
kg/m2
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OMEGA observations of the residual seasonal frost
around South pole. Ls 236?-243?1.5 ?m band
depth
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Ls127?-136?
Ls93?-97?
Ls113?-115?
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Cyclonic vortices Anticyclonic vortex
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Venus case (symmetric mode)
multiple Hadley cells?
convective flow
thermal tide
superrotation
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Titan another superrotating atmosphere
Mingalev et al., 2008
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Vertical velocity on Titan a signature of
thermal tide
z550 km
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Giant planets
zones
belts
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Hot spot
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Polar vortex
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32 km/pix
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