Why are the seasons reversed in the Southern hemisphere when compared to the Northern hemisphere? Like, if it's winter in Europe, it's summer in South America.
The seasons are reversed in the Southern Hemisphere when compared to the Northern Hemisphere due to the tilt of the Earth's axis. The Earth rotates around its axis, which is tilted at an angle of approximately 23.5 degrees relative to the plane of its orbit around the sun. This tilt causes different parts of the Earth to receive varying amounts of sunlight at different times of the year.

When the Northern Hemisphere is tilted towards the sun (during June solstice), it receives more direct sunlight and experiences longer days, resulting in summer. At the same time, the Southern Hemisphere is tilted away from the sun, receives less direct sunlight, and experiences shorter days, resulting in winter.

Six months later, during the December solstice, the Northern Hemisphere is tilted away from the sun, receives less direct sunlight, and experiences shorter days, resulting in winter. At the same time, the Southern Hemisphere is tilted towards the sun, receives more direct sunlight, and experiences longer days, resulting in summer.

Therefore, when it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere and vice versa.