As the so-called dog days of summer have finally arrived, the still-frozen slopes of Yosemite National Park are now sporting what some may know as “watermelon snow” — but don’t confuse it for the popular summertime treat.
Yosemite National Park in California shared photos last Sunday to Facebook of the sight at an unnamed lake in the high country above 9,500 feet. . .
Watermelon snow — also known as “blood snow” or simply red snow — is what happens when snow above 9,500 feet lasts through the summer months.
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Watermelon Snow (or Blood Snow) between Burroughs peaks 2 & 3. Aristotle wrote about it, and it puzzled high alpine and coastal explorers for thousands of years. Turns out it’s just a green algae that has a natural red pigment that protects it from bright UV light. #watermelonsnow #bloodsnow #hiking #washingtonstate #pacificnorthwest #scienceiscool
“This algae is typically green but contains a special red pigment called a carotenoid that acts as a protective barrier, shielding the algae’s chlorophyll,” park rangers stated on Facebook. “Since chlorophyll is necessary for its survival, it uses this natural type of sunscreen to protect itself from too much heat and damaging UV radiation.”
The pigment produced by the algae then dyes the surrounding area a darker color, giving the snowfield a pink or red color. It also can allow the snow to heat up faster and melt quickly, according to the park. (Read more from “‘Watermelon Snow’ Found in National Park” HERE)