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Meteorology
3.3.4 Inversion
Here is an illustration showing the normal
temperature distribution in relation to
height.
Here the temperature drops evenly by
o
about 2 C per 1000 feet.
When the temperature increases with height, it is said that there is an
inversion.
Inversions are frequent near the earth's surface but are also often found in the
free atmosphere. The stratosphere is an inversion, for example.
Inversions can be formed in the
following ways:
- Ground inversion
- turbulence inversion
- subsidence inversion /
height inversion
The figure here shows the different forms of temperature variation with height.
3.3.4.1 Ground inversion
Ground inversion is formed on clear nights
by radiation from the ground.
This will cause a cooling that propagates to
the nearby air layers.
When there is a small amount of
turbulence, the inversion spreads upwards.
The cooling can often form radiation fog.
Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 225
