Watermelon Snow in Montana is Rich in Algae, Threatens US Water Supply

The endearingly named "watermelon snow" in Montana represents another threat to the US water supply. It is pink snow that contains a dangerous amount of algae.

Currently, US researchers are attempting to determine what causes the algae that give snow its pink color.

Snow Algae

Snow algae are a class of green algae known as Chlorophyta that turn red because they produce pigments that are brightly colored, according to the Living Snow Project.

Researchers from all over the world have described a wide variety of snow algae species, and many of the previously named Chlamydomonas nivalis algae now belong to other groups.

If pink, orange, red, or green snow is present, it is probably algae growing there.

It is also likely a thriving community of microbes, including numerous bacteria, fungi, and single-cell predators that eat bacteria and algae, the Living Snow Project reported.

It has also been found that snow algae can travel far distances when carried by the wind.

What's more, pink snow indicates lower albedo, which also means more sunlight absorption and quicker snowmelt. Other factors, such as dust, dirt, and wildfire ash, also affect albedo.

The snowfields clinging to the Clements Mountain lower slopes in Montana's Glacier National Park have been scanned by Jim Elser and his team, a University of Montana ecologist.

Elser is also the director of the Flathead Lake Biological Station.

The instrument was used in the study to calculate the snow's albedo, which is a quantification of how much sunlight is reflected upward.

The researchers also employed a second spectroradiometer to evaluate the pigment to gauge the quantity of the red-pink color spectrum, which is most likely from the snow algae.

Pink Snow and Two Layers of Algal Bloom

In addition to these routine tasks, the team also measured the snow's water content, collected bags of snow samples, and extracted a snow core, revealing two layers of algal blooms, including a noticeable rusty band several inches below the surface.

Different sources provide various types of nutrients. According to earlier studies, nitrogen is blown in from chemical fertilizers and manure in agricultural areas, whereas phosphorus is found in rocks eroded by glaciers.

Although both sorts of nutrients are thought to encourage algal growth, nitrogen is particularly significant to researchers.

They are curious to learn more about the dynamics at work because they believe that wind patterns may increase the frequency of algal blooms in the Intermountain Rockies.

Read also: Black Sprinkles on Yellowstone Snow Not Poppy Seeds, National Park Explains 

Understanding how snow algal growth is influenced by various factors is an essential first step in understanding a changing water source.

For the West of the United States, which is prone to dryness, understanding where algae may hasten snowmelt is crucial.

Potentially, more algae would also mean more melting. Snowmelt occurs gradually, providing reservoirs with a more reliable water supply.

The cold water that the fishing industry and other aquatic life require to survive the sweltering summer months is abundant in streams.

Rapid snowmelt, however, brings about several additional problems.

It's a big deal, especially with the West as a whole experiencing a drought.

If there is going to be another factor that continues to perpetuate earlier melt, that's important, according to Scott Hotaling, a snow algae research team member. He is also a Utah State University assistant professor who studies changing mountain ecosystems.

Pink Snow Frequency

In alpine and arctic regions, including the Sierra Nevada in California, this kind of snowfall occurs frequently in the summer.

At an altitude of between 3,000 and 3,600 meters or about 10,000 to 12,000 feet, the weather is extremely cold all year long. Winter storm snow has thus persisted.

When snow is stepped on or compacted into snowballs, it turns scarlet, Interesting Engineering reported.

Elser and his colleagues discussed their research through High Country News.

Related article: Pink Ice in the Alps: How Threatening to Glaciers Can It Be?