We all know it’s not a good idea to eat yellow snow, but what’s the deal with pink snow? After all, it looks pretty and can even smell like watermelon, which is a tasty fruit.

Pink snow can be found high in the mountains during summer. The pink is actually algae that likes cold temperatures. In the winter, snow covers the algae and it goes dormant. Once spring comes the algae blooms again.

The algae have an unusual diet. They eat carbon dioxide  an invisible gas  from the air to grow, according to researchers at the University of Cincinnati.

Ammonia and nitrate — chemicals found in fertilizers — that become airborne also feed the algae. Sources of the chemicals include car exhaust and cow poo.

Bacteria and other tiny lifeforms that dine on rocks are also blown onto the snow and provide a food source for the high-altitude snow dwellers.

As it grows and spreads, the algae actually warms up the snow by absorbing sunlight, making the snow melt faster. Clean, white snow reflects sunlight.

As the researchers explored they found snow algae that were orange, brown, purple and green, explaining those as different species of algae using different wavelengths of light to harvest energy from sunlight and to protect themselves from UV radiation.

While earlier explorers have observed the colorful algae for centuries, it is only recently that scientists have begun investigating its growth patterns and effects from climate change.

By the way, it’s best not to eat pink snow  or any snow other than white.

— Brett French, Gazette Outdoors editor