Atmosphere - reference notes & pics -
It's important to grasp the structure of the atmosphere.
It has five layers,
Troposhpere (tropos=turning) where most weather
happens, up to 12 km = 100 millibars(=hPa) pressure: temp falls
Stratosphere (stratified and quiet), the opposite
of turning, due to temp. rising with height: warming due to
- Mesosphere - turbulent again, like the troposphere, temp falls
with height; ionized by day to produce D & E layers; meteors
burn up here; noctilucent clouds at dusk;
- Thermosphere - quiet again, due to temp rising with height:
early absorption of solar wind, cosmic rays; ionized plasma VERY
hot but too diffuse to glow except when auroras form
- Exosphere - not really a layer but it's where satellites orbit
At the turns in temperature gradient are the pauses - Tropopause,
Stratopause and Mesopause. Nimbus clubs form at the tropopause.
In the Troposphere, convection and water have huge effects - water
vapour is a far more powerful greenhouse gas than CO2 but its concentration
varies. Convection causes adiabatic cooling which precipitates water
droplets out of water vapour to form clouds; water vapour precipitating
causes warming again; clouds change thermals, insulate at night
and cool by day: the whole thing is way beyond current models though
Eschenbach and others have observed interesting patterns of behaviour
that appear to contribute to water vapour having a homeostatic effect.
Below right is Trenberth's model: this is effective largely in the
Above the troposphere, there is a steady increase of ionized particles
(plasma) with increasing height, and a steady increase of interaction
with, and absorption of, very high energy short-wave radiation from
ultraviolet thru X-rays to cosmic rays. This buffer is essential
to protect life on Earth but is open to cosmic influences in ways
that is still very little understood; particularly electric and
magnetic influences and the effects of, and correlation with, the
"solar system barycentre" ie the solar system's centre
of gravity which dances through and around the Sun itself and appears
to correlate strongly with the sunspot cycle.
I've collected various pictures here to contemplate. Iconically
they can be revealing. Trenberth's diagram's presence doesn't signify
that I think he has got it correct. Just a useful reference point.
Below right is my own modified version of the CISM
atmosphere diagram - I've added a Pressure scale to remind
myself the pressure/altitude correspondence with the atmospheric
Below left the scale is LOGARITHMIC not linear as
above - so the mountain is drawn to scale logarithmically, where
elsewhere artistic licence is used. Below right shows absorption
Here's a picture from World
of Aeronautics that includes pressure scaling, confirming
my pic above.
Page built 8 February 2011