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Meteorology

Here, you can see how water

can transition into different

states.

To change states, energy must

be added or released.

Ice can transition directly to

invisible water vapor without first becoming liquid water. Invisible water vapor

can form frost on a cold bottle or dew on a cold beer (or soda).

3.5.2 Air's humidity content

The presence of invisible water vapor in the atmosphere is responsible for the

formation of clouds, fog, precipitation, and similar phenomena, as water vapor

droplets can condense into numerous water droplets or ice crystals and,

through further growth, develop into precipitation.

If you watch the videos (3.1), you can see the fascinating video about what

happens in a glass when it is placed to cool.

You can read more about it below.

Imagine a glass with air at a temperature of 30°C.

The glass is placed in the refrigerator, and the air will
cool down.

At the bottom of the glass, you will see a small blue

droplet; this is water that has formed from the

condensation of invisible water vapor.

The red area above the water comes from the thermographic camera.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 267