snow or ice surfaces coloured rose to blood red by algae such as Chlamydomonas, Raphidonema, and diatoms. During seasons when there is little sunlight and temperatures are much lower than the freezing point, the algae are dormant. Red snow is the best known and most widely distributed of all snow flora.
RED SNOW
Meaning of RED SNOW in English
Britannica English vocabulary. Английский словарь Британика. 2012