Matt Davey of the University of Cambridge samples snow algae at Lagoon Island, Antarctica.
Sarah Vincent
We have certain expectations of snow. We usually think it will be bright white, but in parts of coastal Antarctica the snow takes on a bizarre shade of green. That’s a color we may be seeing more of as a warming climate impacts the land of ice.
Antarctica isn’t turning into a giant margarita. The green is caused by blooms of microscopic snow algae. The blooms cover so much ground they can be observed by satellites.
A team led by researchers at the University of Cambridge in the UK and the British Antarctic Survey used satellite data and fieldwork observations to create a map of the green algae and predict future growth of the disconcerting green snow. They published their work in the journal Nature Communications on Wednesday.
The green snow appears along the coast. “They grow in ‘warmer’ areas, where average temperatures are just above zero degrees Celsius during the austral summer — the Southern Hemisphere’s summer months of November to February,” said the University of Cambridge in a release on Wednesday.
Nearby penguin colonies appear to play into the algal blooms. We recently learned penguin feces can cause laughing-gas problems for scientists. It can also feed the growth of algae.
Climate change looks like it will play into the inadvertent “greening” of Antarctic snow. “As Antarctica warms, we predict the overall mass of snow algae will increase, as the spread to higher ground will significantly outweigh the loss of small island patches of algae,” said University of Cambridge plant scientist Andrew Gray, lead author of the paper.
Scientists aren’t just seeing green. Parts of Antarctica look like a rainbow. The researchers intend to expand their studies to include red and orange algal blooms that contribute to this multi-colored landscape. “Snow white” it isn’t.
