Overview of Seasons

Seasons are periodic changes in weather patterns, daylight hours, and temperature experienced on Earth. They repeat annually and are driven by the planet’s orientation and movement in space.

Earth’s Axial Tilt and Orbit

• Axial Tilt: The Earth’s axis is tilted at approximately 23.5° relative to its orbital plane.
• Elliptical Orbit: Earth orbits the Sun once every 365.25 days, tracing a slightly elliptical path.

Mechanism of Seasonal Change

Because of the axial tilt, different hemispheres receive varying sunlight angles throughout the year:

• Summer: Hemisphere tilted toward the Sun experiences longer days and higher solar intensity.
• Winter: Hemisphere tilted away from the Sun experiences shorter days and lower solar intensity.
• Spring & Autumn: Transitional periods when both hemispheres receive similar sunlight.

Polar Day and Night Phenomenon

Near the poles, during summer the Sun remains above the horizon for 24 hours (midnight sun), and during winter it stays below the horizon for 24 hours (polar night).

Regions with Six-Month Day/Night

Within the Arctic Circle (66.5° N) and Antarctic Circle (66.5° S), the tilt causes the Sun to stay continuously above or below the horizon for about six months, leading to extended periods of daylight or darkness.

Ecological and Human Impacts

• Wildlife Adaptations: Animals adjust behavior, migration, and hibernation cycles.
• Human Activities: Communities adapt with special lighting, seasonal affective disorder (SAD) management, and tourism focused on polar phenomena.

Conclusion

Seasons result from Earth’s axial tilt and orbit around the Sun, altering sunlight distribution. In polar regions, this tilt creates prolonged periods of daylight and darkness, shaping unique environmental and human adaptations.