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Meteorology
3.3.2.2 Solar radiation over the course of a day
Since Earth rotates around itself within a day, the side of the Earth facing away
from the sun will not receive solar radiation.
Therefore, there will be night on this side, while the opposite side experiences
day due to solar radiation.
3.3.2.3 Daily temperature variation
Solar radiation greatly affects the temperature we experience.
However, it is not the direct shortwave radiation from the sun that warms the
atmosphere. Instead, it is the longwave radiation emitted by the Earth's surface
that does this.
Below is an example of a day when the sun shines unobstructed by clouds all
day.
The coldest time of day is just after
sunrise, when the Earth radiates the
least heat. The warmest time is a few
hours after the sun reaches its zenith
(highest point in the sky).
Day and night temperatures vary greatly.
On sunny days from a cloudless sky, most of the
sun's rays will reach through the atmosphere
and all the way to the earth's surface. It will be
hot.
If there is cloud cover, the sun's rays do not
reach the surface and the temperature is not as
high.
Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 219
