Group B The Seasons

The Earth's axis is the imaginary line through the centre of the Earth between the South and North poles. This axis is tilted slightly compared to the way the Earth orbits the Sun.

We get different seasons (winter, spring, summer and autumn) because the Earth is tilted. This is how it works:

When the northern hemisphere is tilted towards the Sun it is summer in the UK.
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When the northern hemisphere is tilted away from the Sun it is winter in the UK.

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Because of the tilt of the Earth's axis the Sun moves higher in the sky in summer, when we tilt towards it, than in winter.

the North Pole is a little further from the Sun, and so the sunlight hits the North Pole at more of an angle, and it has more of the Earth's atmosphere to go through before it gets to the Earth. That lets the area around the North Pole get colder. In the summer, the North Pole is pointed more toward the Sun, and so the part of the Earth near the North Pole gets more direct sunlight, and becomes warmer. That's the part with the pink guy on it - the United States and Canada and Europe. If you live in Australia, nearer to the South Pole, then you get more direct sunlight when the pink guy is further from the Sun, and his summer is your winter, and his winter is your summer.

This tilted axis is also the reason why there are more hours of daylight in the summer and fewer hours of daylight in the winter. In the winter, the closer you are to the North Pole, the shorter the days are. At the North Pole, it's just dark all winter. In the summer, the closer you are to the North Pole, the longer the days are. At the North Pole, it is light all summer, with no nights at all.seasons.jpg

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