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Meteorology
If you cool the air, it will contract and take up less space.
You can see the principle here.
If we assume that a certain amount of air takes up the
space of the gray bar under standard conditions, the
same amount of cold air will take up less space, while
warm air will take up more.
Example:
On a warm day, the 850 hPa level is high compared to
a standard day.
The opposite is true on a cold day.
3.3.5.7 Variation of air pressure with height
In the standard atmosphere, it is assumed that
pressure decreases by 1 hPa for every 30 feet
you rise.
The figure shows pressure as a percentage
relative to height in feet above MSL.
The following relationship exists between the
air’s volume and pressure and temperature.
The volume of air is inversely proportional to pressure
The volume of air is proportional to temperature
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Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 231
