1. Seasonal Changes
Lesson Introduction

2. Day & Nights
The Earth travels around the sun in an oval shaped path called an orbit.
It takes 365 1/4 days for it to complete one revolution or journey around the sun.
The Earth spins around on its axis– an imaginary line running through its North & South poles.

3. What is a season? A season is one of the four
natural parts of the year.
Winter Spring Summer Fall

4. Why do we have seasons? The changes of the seasons are caused by
the changing position of the earth on its axis.
During the winter months in North Carolina, our part
of the earth is slanted away from the sun.
During the summer months in North Carolina, our part of the earth is slanted toward the sun.

5. The Earth spins on its axis.
An axis is an imaginary straight line that goes through an object – like a planet.
The object (planet) spins around the axis.
Let's try to picture this!
Here is the
imaginary
straight
line.
Now let’s put
it through the
Planet!
Do you see the
planet spinning
around the axis?
That is almost
right!
tilted 23.5 degrees.
Our Planet is
Watch This!
That’s better!

6. Understanding the Seasons
It’s all in the tilt
Summer: - Earth is tilted toward the sun, we get a more direct light, so it’s warmer
Winter: - Earth is tilted away from the sun, we get slanted light, so it’s cooler
No tilt means 1 Season!

7. Understanding Summer and Winter
Summer in the North
Winter in the North ☺ ☹ S ☺ ☹ U
night
day N
South
South
From summer to winter earth
revolves half-way around Sun

8. Energy distribution from Sun
slanted hit
large area
(cooler) U
direct hit
small area
(warmer) N

9. Seasons
During the year, days or nights might seem longer because of the Earth’s tilt on its axis.
The Earth’s tilt/orbit cause changes in temperature.

10. Special Days Vernal Equinox March 20 Winter Solstice Dec 21 Summer
June 21
Autumnal Equinox
Sept 22
Vernal Equinox
March 20

11. Illustration
Draw a picture showing the Earth’s position as it revolves around the sun.
Label each season.