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Meteorology
Why should we care about this?
We should care because the temperature and humidity content of an air mass
are crucial for the stability of the air, which significantly affects flying
conditions.
If an air mass rises or is lifted upwards, only its outer edges will come into
contact with the surrounding air.
Temperature changes will mainly be caused by processes in the air due to the
ascent.
The temperature drop in a rising air mass occurs in the first part of the ascent
according to the dry adiabatic lapse rate.
Once the temperature in the air mass has dropped to the condensation level
(the height at which the air's water vapor begins to condense), the heat
released during condensation causes the temperature drop to decrease, and
from this point, the temperature change follows the saturated adiabatic lapse
rate.
Example:
We lift an air mass with a temperature of 22°C.
It will cool down at a rate of 3°C per 1,000 feet.
When it reaches 2,000
meters, the temperature
and dew point are the
same, and clouds form.
Latent heat is released,
and the cooling rate
decreases to 1.5°C per
1,000 feet.
The air mass will
continue to rise if it is warmer than the surrounding air.
Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 274
