The snow has turned red like blood in Antarctica, outside the Ukrainian base Vernadsky on the island of Galindez: to spoil the candid landscape is the abundant flowering of a microscopic alga, exploded due to the high temperatures and in turn responsible for an acceleration of the melting of the ice. The phenomenon is documented by the impressive images published on Facebook by the Ukrainian researchers themselves.
A single-celled alga dyes the snow in Antarctica red (source: Ministry of Education and Science of Ukraine)
It is precisely their microscopes that revealed the presence in the snow of Chlamydomonas nivalis, a single-celled green alga common in various polar and alpine regions: used to 'sleeping' during the winter, it blooms as soon as the ice begins to melt due to the effect of sunrays.
As a 'young', the seaweed appears green because of the organelles (chloroplasts) that make photosynthesis and has two small tails that allow it to swim. Once it reaches maturity, however, it loses its mobility: to survive the extreme environment, it develops a second insulating cell wall and a layer of red pigments (carotenoids) which give it a particular color ranging from orange to red.
The single-celled alga that dyes the snow in Antarctica red (source: Ministry of Education and Science of Ukraine)
"This layer - explains the researchers in their post - protects the seaweed from ultraviolet rays", but absorbing heat promotes the melting of the ice: the effect, useful for the growth of the seaweed, however, risks contributing to climate change.
A single-celled alga dyes the snow in Antarctica red (source: Ministry of Education and Science of Ukraine)