What is the condition that causes snow to be red or pink?”
Watermelon Snow A Strange Phenomenon Caused by Algal Cells of The Chlorophyta Have you ever hiked across an alpine meadow or traversed a steep talus slope in high mountain ranges and noticed pinkish patches, or streaks of red, on the snowbanks? This phenomenon is especially common during the summer months in the Sierra Nevada of California where snow has lingered from winter storms, mainly at altitudes of 10,000 to 12,000 feet. Compressing the snow with your boot leaves a distinct footprint the color of watermelon pulp. The snow even has a fresh watermelon scent and is sometimes called “watermelon snow.” Walking in pink snow often results in a temporary discoloration of your clothing, such as bright red soles and pinkish pant cuffs. There are unconfirmed reports that consuming “generous quantities” of pink snow may cause diarrhea, a rather distressing situation above timberline. Snowbanks of colorful pink snow are a common sight during summer on alpine slopes of California’s Sierra Nev
Watermelon snow, also called snow algae, is snow that is reddish or pink in color, with the slight scent of a fresh watermelon. This type of snow is common during the summer in alpine and coastal polar regions worldwide, such as the Sierra Nevada of California. Here, at altitudes of 10,000 to 12,000 feet (3,000–3,600 m), the temperature is cold throughout the year, and so the snow has lingered from winter storms. Compressing the snow by stepping on it or making snowballs leaves it looking red. Walking on watermelon snow often results in getting bright red soles and pinkish pant cuffs. Watermelon snow is caused by the presence mainly of Chlamydomonas nivalis, a species of green algae containing a secondary red carotenoid pigment (astaxanthin) in addition to chlorophyll. Unlike most species of fresh-water algae, it is cryophilic (cold-loving) and thrives in freezing water. Its specific epithet, nivalis, is from Latin and refers to snow.
