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Why Do the Seasons Change on Earth?為什么會(huì)有四季的變化?

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Two things cause the seasons to change. First, the Earth moves around the Sun. Second, the Earth has a tilted axis of rotation.

The Earth spins around an axis. This imaginary line extends from the South Pole to the North Pole. The Earth’s axis is not vertical. It’s actually tilted at an angle of 23.5°. The planet is always tilted in the same direction as it moves around the Sun.

What does the Earth’s tilted axis have to do with seasons? It means that different parts of the planet are tilted toward the Sun at different times of the year. It’s also why the seasons are different in different parts of the world.

Not all parts of the Earth have four distinct seasons. But they all experience seasonal variation. Closer to the North Pole and the South Pole, daylight and temperatures change with the seasons. Near the Equator, days are always about 12 hours long. But these areas usually have a wet season and a dry season.

引起季節(jié)變化的原因有兩個(gè):地球圍繞太陽運(yùn)動(dòng),地球的自轉(zhuǎn)軸傾斜。(剩余1566字)

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