Wintery white tinged in green
The snow in Antarctica is turning green and scientists say climate change may be to blame.
According to a study published in the peer-reviewed Nature Communications, microscopic algae blooms across the surface of the snow is slowly turning Antarctica’s wintry, white landscape green.
Although microscopic, scientists say they’re able to see the “green snow” from space when the algae blooms en masse.
Researchers from the University of Cambridge and the British Antarctic Survey created a large-scale map of green snow algae along the Antarctic Peninsula coast using a combination of satellite data and on-theground observations over the course of two summers.
The study found that the green snow algae bloomed in warmer areas where the average temperatures are just above zero Celsius during the southern hemisphere’s summer months from November to February.
Although algae prefer warmer temperatures, scientists believe that rising global temperatures could also be to their detriment.
Low-lying islands with no high ground may lose their summer snow because of climate change and with it, their snow algae.
“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 Dr. Andrew Gray, lead author of the paper, and a researcher at the University of Cambridge and NERC Field Spectroscopy Facility, Edinburgh.
However, researchers say larger blooms of algae can be found north of the Antarctic Peninsula and South Shetland Islands, where it can spread to higher ground as the snow melts.
The team also discovered marine birds and mammals influenced the distribution of algae. More than 60 per cent of algae blooms were found within two kilometres of a penguin colony. Scientists hypothesize this may be due to their droppings, which act as a “highly nutritious fertilizer.”
During their two summers in Antarctica, researchers found other algae that turned the snow red and orange.
Although they were unable to measure the different colours, they plan to return and further their work to include other algae blooms.
“This is a significant advance in our understanding of land-based life on Antarctica, and how it might change in the coming years as the climate warms,” said Dr. Matt Davey in the University of Cambridge’s Department of Plant Sciences, who led the study.