Eli5: If the ocean moderates temperatures and prevents extreme cold or extreme heat, why is the arctic ocean so cold?

Question

I just find it strange haha

In: 2

Answer 1

The poles get a lot less sunlight than the equator does. So they will be colder than the regions where the sun is overhead. During the norther hemisphere winter, the north pole gets no sunshine at all. So it cools down to below freezing and the seawater forms an ice layer. Which isn’t all that thick, submarines can surface through it.