Snow and ice algae are cold-tolerant algae growing on snow and ice and have been reported on snow fields and glaciers in many parts of the world. Visible snow algal blooms are well known as red snow or watermelon snow. The color is caused by red-pigmented Chlorophyta (green algae, usually Chamydomonas nivalis) and has been well studied taxonomically and physiologically on snow fields. More than 100 species of snow algae have been reported in the world and they are mainly green algae or cyanobacteria. The snow algae sustain cold-tolerant animal and bacterial communities on snow fields and glaciers. The ecology of snow algae is important for understanding the glacial ecosystem.
