What is watermelon snow?

Otherwise known as glacier blood, watermelon snow is found worldwide in mountains and polar regions. The pink-red snow has a faintly fruity smell but is reported to have laxative effects if eaten.

The watermelon colour comes from freshwater green algae called Chlamydomonas nivalis. In summer, the algae produce a red pigment to protect themselves from the Sun’s intense rays. This pigment belongs to a large group of carotenoid substances, many of which are found in brightly coloured fruits and vegetables such as tomatoes and carrots.

Unfortunately, the pigment reduces snow’s ability to reflect heat, leading to faster melting rates.

Read more:

• Is there acid snow (like acid rain)?
• Why are some icebergs green?
• Why don’t hailstorms last as long as rainstorms?
• Why does rain smell so good?

Asked by: Connor Sykes

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