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Meteorology

3.2.1.2 Temperature gradient and isothermal conditions

When the temperature drops with increasing height, this is called a positive

temperature gradient.

The temperature decreases by approximately 2°C per 1,000 feet (about 3,000

meters) as we ascend to the tropopause.

Here, the temperature is a constant -56°C up to the ozone layer, where the

temperature increases with height.

This phenomenon is called isothermal conditions, where the temperature

remains constant with altitude.

3.2.2 The Stratosphere

The stratosphere begins where the temperature starts increasing with height,
known as an "inversion" (from the term "inverse," meaning reversed).

In the stratosphere, we have an ozone layer that blocks harmful UV radiation

from the sun.

The air’s content of pollution particles, dust, salt, etc., plays a major role in the

formation of clouds, fog, and precipitation, as raindrops form around such small

particles.

These factors contribute to the weather we experience, though the sun and
moon also play a role.

Meteorologically, the air contains dry air, water vapor, and pollution particles.

There are 4 properties of the atmosphere that - Temperature

are particularly important for the weather - Humidity

around us:
- Air pressure

- Wind

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Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 216