Why Do Seasons Change?


Quick Answer

Seasonal changes occur due to differences in tilt along the Earth's axis. The Earth's axis, although a straight line, never stands directly vertical. The Earth tilts as it orbits the sun, which in turn exposes some parts of the world to more sunlight, leading to longer and warmer days, while the other side receives less light, creating darker and colder days.

Continue Reading
Why Do Seasons Change?
Credit: Dawn Ellner CC-BY 2.0

Full Answer

Despite the Earth tilting on its axis, the axis always remains the same distance from the sun. Areas of the Earth receive less light or more light depending on its position relative to the sun and degree of axis tilt. Some regions receive more sunlight year-round, primarily the equatorial regions. However, other areas receive equal amounts of light and darkness, causing four distinct seasons.

Regardless of weather patterns, the Earth divides into a northern and southern hemisphere. These hemispheres experience opposite seasons: the summer months in the northern hemisphere correspond with winter months in the southern hemisphere, and vice versa. Summer occurs in one hemisphere when the sun shines directly on that part of the Earth, exposing it to more intense and prolonged light. The other half, meanwhile, receives indirect and less powerful sunlight, creating winter conditions. In the fall and spring seasons, the two hemispheres receive equal amounts of sunlight, which moderates the amount of light and temperatures.

Learn more about Months & Seasons
Related Videos

Related Questions