In summer, parts of Antarctica turn bright green as algae bloom on the surface of melting snow.


Snow in Antarctica is turning green and scientists say climate change may be to blame.

According to a study published in the peer-reviewed agency Nature Communications, microscopic algae bloom on the surface of the snow, slowly turning the winter, white landscape of Antarctica into green. Although microscopic, scientists say they are able to see “green snow” from space when algae bloom en masse.

Researchers at the University of Cambridge and the British Antarctic Survey have created a large-scale map of green snow algae off the coast of the Antarctic Peninsula, using a combination of satellite data and field observations over two summers.

Green snow algae, Rothera Point, Antarctica 2018 (Photo: Matt Davey)

The study found that green snow algae bloom in warmer regions, where average temperatures are just over 32 degrees Fahrenheit in the summer months of the southern hemisphere from November to February.

While algae prefer warmer temperatures, scientists believe that rising global temperatures could also be to their detriment. Low-lying islands without high land can lose their summer snow due to climate change, and with them the snow algae.

“As Antarctica warms, we predict that the total mass of snow algae will increase, as the spread to higher ground will significantly exceed the loss of small island algae spots,” said Dr. Andrew Gray, lead author of the article. and researcher at the University of Cambridge and the NERC Field Spectroscopy Facility, Edinburgh.

However, researchers say larger algae flowers can be found north of the Antarctic Peninsula and the South Shetland Islands, where it can spread higher as the snow melts.

The team also found seabirds, and mammals influenced the spread of algae. Over 60% of algae blooms are found within three miles of a penguin colony. Scientists hypothesize that this may be due to their discharges, which act as a “high-nutrient fertilizer.”

During their two summers in Antarctica, researchers discovered other algae that turned snow red and orange. Although they failed to measure the different colors, they plan to return and continue their work to include other flowering algae.

“This is a significant advance in our understanding of terrestrial life in Antarctica and how it may change in the coming years as the climate warms,” ​​said Dr. Matt Davy of the Department of Plant Science at Cambridge, who is leading the study.

Follow Adriana Rodriguez on Twitter: @AdriannaUSAT.

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