You can get a sense of how much the Sun affects the Earths temperature by standing outside on a partly cloudy day.
When the Sun is behind a cloud, you feel noticeably cooler than when it isnt. The surface of our planet absorbs this heat from the Sun and emits it the same way that pavement continues to give off heat in the summer after the Sun goes down. Our
atmosphere does the same thing-it absorbs the heat that the ground emits and sends some of it back to the Earth.
The Earths relationship with the Sun also creates seasons. The Earths axis tips a little-about 23.5 degrees. One hemisphere points toward the Sun as the other points away. The hemisphere that points toward the Sun is warmer and gets more light--its summer there, and in the other hemisphere its winter. This effect is less dramatic near the equator than at the poles, since the equator receives about the same amount of sunlight all year. The poles, on the other hand, receive no sunlight at all during their winter months, which is part of the reason why theyre frozen.
Most people are so used to the differences between night and day that they take them for granted.
But these changes in light and temperature have an enormous impact on other systems on our planet. One is the circulation of air through our atmosphere. For example:
The Sun shines brightly over the equator. The air gets very warm because the equator faces the Sun directly and because the ozone layer is thinner there.
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