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Meteorology
The horizontal pressure gradient at any point is perpendicular to the isobar
through that point and directed from higher to lower pressure.
3.4.2.2 Coriolis Force
If air movements were only influenced by gradients, winds would blow directly
from north to south or from south to north.
However, they are also influenced by the Coriolis force.
The Coriolis force arises due to Earth's rotation. This force causes moving
objects, such as air, to deviate
from their original path.
Winds are deflected to the right
north of the equator and to the
left south of the equator.
This creates wind and pressure
belts in the three circulation
systems.
The pressure gradient creates wind, while the Coriolis force affects the wind's
direction and causes the wind not to move directly from high to low pressure
but to curve and form spiral movements (as in a low-pressure system or a
cyclone).
Between the subtropical highs and the equatorial lows, the warm trade winds
blow, which, due to the Coriolis force, are deflected westward and become the
southeast and northeast trade winds.
From the high polar pressure, cold polar winds blow.
Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 249
