Why do we have seasons?

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 Seasons occur due to the tilt of Earth’s axis, which is approximately 23.5°. Because of this tilt, each hemisphere receives different amounts of sunlight through the year. The Earth’s distance from the Sun, even though it changes slightly over a year, is not a factor in the change of seasons.

When a hemisphere leans toward the Sun, the Sun’s rays hit it more directly, leading to longer days and increased absorption of solar energy, producing the warmer temperatures of summer. The hemisphere facing away from the Sun receives less direct sunlight, resulting in winter.

Latitude also influences how seasons are experienced. The Equator is lit more consistently throughout the year because the Earth bulges outward somewhat there. Since sunlight strikes equatorial regions more steadily year-round, the variation in temperature and, therefore, in seasons in these regions is less pronounced. In contrast, higher latitudes experience more pronounced seasonal changes due to the greater difference in solar angle between summer and winter. This is why tropical regions have less temperature fluctuation, while temperate regions have more distinct seasons.