Earth & Space
Why are the poles so cold?
Sunlight reaches the poles differently. Puschel explores angles of light and seasons.
The short answer
Near the poles, sunlight strikes the ground at a shallow angle. Its energy spreads over a larger area, warming it less strongly. Long dark winters and bright ice add to the cold.
An imagined Wusel scene
Puschel and Flauschi investigate
With Lumi, Puschel shines a torch straight at paper, then at a slant. Flauschi outlines both patches. The slanted patch is larger. He sees: the same lamp spreads its light over more area. They keep it out of everyone's eyes.
Try explaining it
What happens to the same amount of sunlight at a shallow angle?
Choose a), b) or c), then explain your choice.
- a)It spreads over more ground.
- b)It spreads over a smaller area and warms it less.
- c)It spreads over the same area regardless of angle.
Show the explanation
Correct: a): It spreads over more ground.
Near the poles, sunlight strikes the ground at a shallow angle. Its energy spreads over a larger area, warming it less strongly. Long dark winters and bright ice add to the cold.
Explore in more detail
Here you will find longer explanations and further details. You can explore them together.
Understand step by step
How it works – simply explained
Light arrives at a shallow angle
Near the poles sunlight spreads the same amount of light over a larger area than steeply incoming rays.
Less warming per area
Spreading means less solar energy per area. Long winter darkness reduces warming further. Distance from the Sun is not the main explanation.
Bright surfaces reflect
Snow and ice reflect much sunlight, so not all that energy warms the ground. Arctic and Antarctic still differ: chiefly an ocean region versus a continent.
Why the same rays cover more area
Imagine a light patch compact when aimed straight at a surface, but stretched when aimed obliquely. Energy then spreads over more area. Sunlight reaches polar regions at shallower angles than places near the equator, giving less energy per equal surface area. The equator is the imaginary line around Earth midway between its poles.
The key points again
Discovery 1
Near the poles sunlight arrives at a shallower angle, spreading its energy over a larger area.
Source: [1]
Discovery 2
Long winter darkness further reduces heating.
Source: [1]
Discovery 3
Bright ice and snow reflect much sunlight. The Arctic and Antarctic are still different regions.
Source: [2]