Because the Earth's axis of rotation is tilted. When the Earth is on one side of the Sun, the Sun shines more on the northern hemisphere, and when it's on the other side 6 months later, the Sun favors the southern hemisphere. read more
The seasons are reversed in the Southern Hemisphere because when the Northern Hemisphere is tilted toward the sun, the Southern Hemisphere is tilted away from it. Thus, when the Northern Hemisphere is receiving more direct sunlight and undergoing summer, the Southern Hemisphere is deep in the cold of winter. read more
Because the Earth’s axis of rotation is tilted. When the Earth is on one side of the Sun, the Sun shines more on the northern hemisphere, and when it’s on the other side 6 months later, the Sun favors the southern hemisphere. read more
Simply because of the tilt of the Earth. Because of this inclination, the northern hemisphere, receives more energy from the Sun, While the southern hemisphere receives less. read more