-
Brrr! Whose idea was
it to camp in winter?
-
And why is winter
-
so much colder and
darker than summer?
-
To understand this, we
need to explain how
-
the tilt of the
Earth's axis
-
affects the amount
of sunshine we get,
-
and explain how
the tilt of
-
the Earth's axis affects
-
how warm the sun feels.
-
The Earth spins
on its axis.
-
The fact that it takes
24 hours to complete
-
one spin helps us
explain day and night.
-
But it is the tilt of
-
the Earth's axis that will
-
help us understand
the seasons.
-
It is tilted at an
angle of 23.4 degrees,
-
and the Earth takes
-
one year to orbit the sun.
-
Different parts
of the Earth are
-
tilted towards the
sun as it orbits.
-
In winter, the
northern hemisphere
-
is tilted away
from the sun.
-
This means fewer
hours each
-
day are spent in daylight.
-
In summer, the
northern hemisphere
-
is tilted towards the sun.
-
This means more hours
-
each day are spent
in daylight.
-
The tilt of the Earth
-
also affects
the angle that
-
the sun shines onto
-
different parts
of the Earth.
-
In the summer, the sun is
-
shining more directly
-
at the northern
hemisphere.
-
In the winter, the sun
-
shines at more
of an angle.
-
The sun appears
higher in the sky in
-
summer and lower
in the winter.
-
The angle of the sun
in the winter spreads
-
the sun's rays over
a larger area.
-
They are less
concentrated,
-
and so it feels colder.
-
So, the Earth's tilt
really does mean
-
it's better to
go camping in
-
the UK in summer.
-
In winter, the
Northern hemisphere
-
is tilted away
from the sun.
-
We have fewer
hours of daylight,
-
and the sun's rays
are spread over
-
a larger area,
meaning it's colder.
-
In summer, the
northern hemisphere
-
is tilted towards the sun.
-
We have more hours of
daylight and the sun
-
shines more directly onto
-
us, meaning it's warmer.
-
I know which one I prefer.
-
[bird song]
