Seasons explained

_Elsa_

Tiffi find more information about the different seasons.

‘The cycle of seasons is caused by Earth's tilt on its axis and the planet's orbit around the sun. When the axis points toward the sun, that hemisphere experiences summer. The hemisphere tilted away from the sun experiences winter. After Earth travels a quarter of the way around the sun, the axis is pointed along the planet's path, parallel to the star. (Info here)

The tilt in the axis of the Earth is called its obliquity by scientists.

Over the course of a year, the angle of tilt does not vary. In other words, Earth’s northern axis is always pointing the same direction in space. At this time, that direction is more or less toward the star we call Polaris, the North Star. But the orientation of Earth’s tilt with respect to the sun – our source of light and warmth – does change as we orbit the sun. In other words, the Northern Hemisphere is oriented toward the sun for half of the year and away from the sun for the other half. The same is true of the Southern Hemisphere.

When the Northern Hemisphere is oriented toward the sun, that region of Earth warms because of the corresponding increase in solar radiation. The sun’s rays are striking that part of Earth at a more direct angle. It’s summer.

When the Northern Hemisphere is oriented away from the sun, the sun’s rays are less direct, and that part of Earth cools. It’s winter.

The tilt in Earth’s axis is strongly influenced by the way mass is distributed over the planet. Large amounts of land mass and ice sheets in the Northern Hemisphere make Earth top-heavy. An analogy for obliquity is imagining what would happen if you were to spin a ball with a piece of bubble gum stuck near the top. The extra weight would cause the ball to tilt when spun. (Read more here) 

This information is way over Tiffi’s head. She will take their word for it! 

Let’s continue - The leaves are changing colors

Start at the beginning – Seasons come and seasons go – the story of the wolf