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Meteorology
In summer, the morning sun can quickly heat the air, so that the inversion
disappears. In winter, it is difficult.
3.3.4.2 Turbulence inversion
When the wind speed is high, the
turbulence can cause an inversion to
form at the top of the turbulence layer.
The inversion is formed by the air near the ground cooling with height.
This causes a subsidence from the above. The subsiding air is heated and mixed
with the surroundings.
Stratus clouds or stratocumulus clouds often form in the inversion layer.
3.3.4.3 Subsidence inversion / height inversion
Subsidence means a slow subsidence of
air over a large area.
Occurs especially in high pressure areas.
o
The subsiding air will warm up by 3 C per
1000 feet of subsidence.
The layer below 2000 feet will not
participate in this subsidence. The inversion layer is typically located at 2000-
3500 feet.
3.3.4.4 Frontal inversion and advection inversion
Frontal inversion occurs when an inversion layer is formed when warm air
comes to lie over colder air along sloping front surfaces. The air under the front
cannot rise, as the inversion blocks the ascent of air
Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 226
