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Meteorology

3.5 Humidity and precipitation Meteorologi 3 – 3 videoer

Water Content in the Air:

- 99% is found below 10 km.

- 50% is found below 6,000 feet.

All water is part of a closed system where the total amount of water on Earth

does not change over time, but water constantly moves between different

reservoirs (sea, atmosphere, land, and rivers).

This system is called the water cycle.

Here you can see

how the water cycle
works. Water hits

the Earth as rain. The

rainwater seeps into

the ground or water

bodies, from which it

evaporates over time

and rises into the

atmosphere again.

The numbers indicate the estimated water amounts in 1,000 km³ per year.

3.5.1 States of water

Water exists in three forms:
- Invisible water vapor

- Water droplets

- Ice

When water evaporates, it adds water vapor to the air. When it rains, the water

returns to the Earth's surface again.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 266