Page 247 - PPL-engelsk 2025

Meteorology

3.4.1.1 The global wind system and high-pressure and low-pressure belts

The winds we experience in Denmark are part of a large wind system that

covers the entire Earth.

This is called the global wind system.

At the equator, there is the greatest solar radiation. Here, warm air masses are
formed, which rise upwards.

At the poles, there is the least
solar radiation. Here, air

masses sink.

In both areas, the surrounding

air masses are set in motion.

This creates 4 global high-
pressure belts and 3 global

low-pressure belts, as shown

in the figure.

Over the Equator, where the sun is directly overhead, a large thermal low-
pressure belt forms around the Earth.

This is called the equatorial low-pressure belt.

On both sides of the equatorial low-pressure belt, there are two zones of high
pressure.

These are called subtropical high-pressure belts.

At the poles, we have the coldest areas on Earth. Thermal high-pressure forms

here, which we call polar high pressure.

In the temperate zones between the polar highs and the subtropical highs, we

find low-pressure zones.

These zones are called the temperate low-pressure belts.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 247