The landscape and weather change greatly during the year in regions that have four distinct seasons.
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What Causes the Seasons?

Let's get rid of some common misconceptions about the seasons. The Earth's orbit is in the shape of an ellipse, so that sometimes the Earth is a little bit closer to the Sun than at other times. Is this the cause of the seasons?

You can imagine that if the seasons were caused by the Earth's orbit, people in the northern hemisphere and people in the southern hemisphere would have the same seasons. For example, if winter occured because the Earth was far away from the Sun, everyplace on the Earth would be cold at the same time.

But this is not what happens! Summer in the northern hemisphere occurs at the same time as winter in the south, and vice-versa. It turns out that the Earth's orbit is nearly perfectly circular, and the difference between its closest point and its furthest point is very small. In fact, the Earth is furthest away from the Sun in June when it is summer in the northern hemisphere.

The Earth is a very special planet in many ways. Just as Earth's unique atmosphere and its distance from the Sun work together to make Earth the right temperature to support life, Earth's orbit and its rotation work together to create the seasons.

Last modified June 26, 2008 by Vanessa Pearce.

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