Page 172 - Science Course 3 (Book 2)

Mo12-L2b: Why Do the Seasons Change?

During one half of Earth’s orbit, the north end of the During the other half of Earth’s orbit, the north end of
rotation axis is toward the Sun. the rotation axis is away from the Sun.

Northern Hemisphere receives more sunlight Northern Hemisphere receives less sunlight

N N

S S

Southern Hemisphere receives less sunlight Southern Hemisphere receives more sunlight

Due to Earth’s tilt, the northern hemisphere receives Due to Earth’s tilt, the southern hemisphere receives
more solar energy. more solar energy.

Temperatures increase in the northern hemisphere Temperatures decrease in the northern hemisphere
and decrease in the southern hemisphere. and increase in the southern hemisphere.

This is when spring and summer happen in the This is when fall and winter happen in the northern
northern hemisphere, and fall and winter happen in hemisphere, and spring and summer happen in the
the southern hemisphere. southern hemisphere.

Northern Hemisphere Seasons.

Winter
(December 22)
Spring
(March 21)
Spring Summer
Northern Hemisphere

Autumn
(September 23)

Fall Winter
Southern Hemisphere Summer
(June 21)

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