Many scientific disciplines deal with the temporal characteristics of nature. Detailed knowledge of the causes and consequences of the seasons is important in agriculture, weather and climate research, ecology, medicine and tourism. This web portal offers a lot of interesting information on this topic.more

Image: LaMantarraya, stock.adobe.commore

How Seasons Form

The earth orbits the sun once in 265 days. During this journey, the solar radiation on the globe and as a consequence the temperature changes. Light and temperature are important factors that influence the vegetation and fauna of the earth.

The earth’s axis is tilted by 23.5° compared to it’s travel route around the sun (the ecliptic). During its orbit around the sun the earth once inclines the southern and once the northern hemisphere more towards the sun.

The sun rays fall steeper on to the side of the earth’s surface which is inclined towards the sun. This makes the floor warm more than on the other side. The sun describes a high arc in the sky and is visible longer.
→ We experience long, warm summer days (illustration, left side).

If the northern hemisphere is not inclined towards the sun, the sun's rays fall very flat on the earth and can warm the surface less. The sun stands low in the sky and the arc it describes is much shorter.
→ It is wintertime (illustration, right side).

How Seasons are Formed
How Seasons are FormedImage: Sarah Arnold
Sonne und Erde von der ISS aufgenommen
Image: STS-129 Crew, NASA

Picture of the sun and the earth taken from the ISS.

  • 21.3.
  • 21.6.
    Summer solstice (longest day)
  • 23.9.
  • 21.12.
    Winter solstice
    (shortest day)