Wait, What? Here's Why Snow Is Turning Pink in Some States All of a Sudden
Everything to know about "watermelon snow" or "blood snow."
There is a strange phenomenon happening in the western mountains of the United States and in different spots around the world—the snow is taking on a pink hue! And while it may seem timely, it has nothing to do with Valentine's Day coming up (you would think that someone was giving a festive flair to the snow with the bright pink streaks that are happening high in the peaks). However, it actually has a fascinating cause, and we've got all the details on exactly why snow is turning pink.
Here is everything that you need to know about pink snow which is also referred to as "watermelon snow," "snow algae" and "blood snow."
Related: Can You Get Sunburned in the Snow?
Why Snow Is Turning Pink
Snow turns a pink hue because of something known as green algae. On mountains across the U.S. as well as different parts of the world like the Arctic and Antarctica, the algae are growing rapidly, causing melting snow that turns the color pink. The algae then become more concentrated as the snow decreases. This darkens the surface of the snow (which causes even more melting). The shade the algae leaves behind ranges from pink to blood red.
The specific alga that is responsible for turning the snow pink is called Chlamydomonas nivalis. Environmental science professor Robin Kodner recently explained to NPR, "When the algae cells are growing in the snow, they produce a red-colored pigment that turns the snow pink, or if the algae are in really high numbers, they can turn the snow red. And that pigment helps act as a sunscreen for the algae. It helps protect them from high light levels."
In other words, Chlamydomonas nivalis contains mostly green pigment, but it is a unique snow alga because it also contains a secondary red pigment. When the algae gather in high concentrations in the snow, this red pigment makes it appear pink or reddish. The red pigment occurs because the algae contain a high concentration of carotenoids (which is the same type of red pigment that is in tomatoes).
During the winter, snow covers the algae and they become dormant. As it gets warmer in the spring, the snow begins to melt. This causes the nutrients that trigger the algae to begin to germinate. As the algae grow, the bloom causes streaks or patches of pink color to form at the surface of the snow. Since algae grow in water, the more the snow melts the more algae thrive.
Related: What Cities Across the U.S. Get the Most Snow?
What Makes Pink Snow Turn Orange?
When the cells of the algae are compressed, they get a higher concentration of carotenoids which make the color darker. In fact, according to Interesting Engineering, "Snow turns scarlet when it is stepped on or compressed into snowballs. You frequently end up with bright crimson soles and pink trouser cuffs after walking in watermelon snow".
In a study done by Science Times, they found that there were two layers of algal blooms, one of which was a rusty band just a few inches below the surface. This could account for the compressed snow having more of an orange tint instead of just a deeper red.
Why Does Pink Snow Occur High on Mountains?
Chlamydomonas nivalis thrives in cold temperatures with intense sunlight. So, high-altitude mountain tops are ideal, as are polar snow fields. The algae thrive the most where there is snow all year.
Related: Is Snow Safe to Eat?
Is Pink Snow Harmful?
Although this pink snow is sometimes called watermelon snow and even has a faint sweet smell, it could be toxic to ingest. Just like you wouldn't eat yellow snow, you also need to stay from pink snow. According to Smithsonian Magazine, "It is possible that snow algae might be contaminated by bacteria and toxic algae that are harmful to humans. Eating large quantities of watermelon snow has been known to cause digestive ailments, although the tolerance level of each person’s digestive system might be different".
So, if you are hiking through the mountains on a spring or summer day, don't get tempted by the sweet look and smell of the watermelon snow. What seems like an opportunity at a refreshing snow cone could actually make you sick. Basically, you can think of it as a laxative.
Besides pink snow being potentially toxic to eat, there is also some worry that the faster-than-normal snow melt could be hazardous to the environment. However, more research needs to be done to determine the exact dangers.
Next Up: You'll Glove These 75 Funny and Sentimental Snow Quotes That Will Warm Your Heart!
