"Looks cool, but can cause problems"

Chlamydomonas nivalis, a green algae, grows in snow. When sunlight hits the algae, a red pigment is formed. It protects the algae from solar radiation, which is amplified when the sun is reflected in the snow.

- The pink snow looks cool in pictures, but it can cause some problems, says SVT's meteorologist Tora Tomasdottir.

White snow reflects sunlight, while colored snow absorbs it to a greater extent.

- When the snow is colored, it melts faster. In a warmer climate, we will have a longer season with water on the ice - and thus a longer season with these algae. And those with their red color will in turn make the ice melt even a little faster, says SVT's meteorologist Tora Tomasdottir.