Fact number one: Watermelon snow is bad news.

Before getting too fascinated with watermelon snow, here are some things you need to know, such as what it really is and what it means for the environment.

For centuries, mountaineers who had come across pink snow had been puzzled. Even scientists could not find an explanation as to what has brought these pink blotches on snow--until Scottish botanist Robert Brown figured it out.

According to Science Alert, in 1818, Captain Ross and his team sailed from England to search for the Northwest Passage and chart the Arctic coastline of North America. But their journey was cut short due to severe weather. On their way back, he noted that they came across reddish snow.

By the end of 1818, he published a full account of his expedition and included in the appendix an explanation written by famed Scottish botanist Robert Brown--best known for the Brownian motion, or the continuous motion of minute particles in solution. In the appendix, he suggested that the reddish snow is due to an alga, a photosynthetic microbe.

What are watermelon algae?

Watermelon algae--also known as snow algae, pink snow, red snow, or blood snow--grow in semi-permanent to permanent snow or ice in the alpine or polar regions of the world, as per the Department of the Environment Australian Antartic Division.

The snow algal flora is thought to be dominated by chlamydomonads, a group of green algae characterised by single cells with two flagella at their anterior ends.

Jennifer Frazer of the Scientific American Journal said the most common species of snow alga is Chlamydomonas nivali, an alga that contains green pigment but also contain a secondary pigment, which is red.

But why are they red?

Just like any other algae species, Chlamydomonas nivali are normally green, but due to being exposed to harsh conditions such as ultraviolet (UV) rays, they have developed a number of features which include red pigments.

Placing the snow in a compact space increases the density of the red cells and heightens the color which explains why sometimes it is pink and sometimes blood red.

Can you eat it?

The watermelon snow may look enticing and refreshing. but as per research, you cannot eat it. Eating large quantities of watermelon snow has been known to cause digestive ailments, Smithsonian Magazine said.

As earlier noted, Chlamydomonas nivali turns red when exposed to UV rays. The New York Times explains that red coloration of algae is their way of showing that they are protecting themselves from the UV rays.

But what does it mean for the environment? A research from a team of geobiologists in Germany and Britain said the red algae is darkening the snow, causing it to melt faster.

"Imagine wearing black instead of a white T-shirt in the sun. It feels much hotter," wrote Stefanie Lutz, one of the authors, in an e-mail exchange with The New York Times. "It is the same for the snow: More heat means more melting.

The problem with the watermelon has to do with albedo, or the amount of reflectivity an object emits. That is bad news for the Arctic and the species living on the region that is already warming faster than anywhere else on the planet.