Blood Snow
© Andriy Zotov
Streaks of red algae coat the Antarctic ice in "blood snow."
A strange phenomenon variously dubbed by scientists as "watermelon," "raspberry," and "blood" snow has affected part of Antarctica. Here the normally white landscape has been transformed into a variegated red. How has this happened?

The first appearance of the 'red' snow was reported by Smithsonian Magazine, occurring during late February 2020. This was later confirmed by the Ministry of Education and Science of Ukraine, with the images taken close to Ukraine's Vernadsky Research Base (Galindez Island).

The following video provides a scan of the red snow:

The reason for the red snow relates to algal habitat blooming following the onset of melting.
The patterns for snow algal shows diversity, in terms of growth patterns and pigmentation (pigmentation is due to the production of carotenoids).

What is of concern is that the algae accelerates snow melting and this increases the time and area of exposed bare ice, and the overall effect is linked to changing climate. As has been widely reported, Antarctica has experienced record high temperatures during the early part of 2020.

The algae are capable of surviving the extremely cold temperatures common in Antarctica throughout the winter. Now that temperatures have increased the algae are growing in large numbers, turning the snow red an further affecting the climate of the region.The alga has been identified as Chlamydomonas nivalis, and this biflagellated single-celled algae has the potential to jumpstart a feedback loop of warming and melting. The algae is green but it produces a red pigment as the ambient temperature increases.

According to Newsweek: "Snow blossoms contribute to climate change. Because of the red-raspberry coloring, the snow reflects less sunlight and melts faster. As a result, it produces more bright algae." In other words, a feedback loop of warming, melting, and blooming.

The red coloration appears to have only affected the area close to Antarctica's northern peninsula, significantly impacting on the albedo of the snow and ice. This area has experienced peak melt, which is a direct connection to global heating.

An earlier inquiry into the red snow was reported to Nature Communications, where the research paper is titled "The biogeography of red snow microbiomes and their role in melting arctic glaciers."