Rahul Somvanshi
Small dark patches are appearing on Greenland‘s ice, and they’re causing big problems. These patches are actually tiny algae – microscopic plants that grow on the ice surface. New research shows these algae are making the ice melt faster than expected.
“On the west coast of Greenland, around a tenth of the ice melt is already caused by these microscopic inhabitants,” says Laura Halbach from the Max Planck Institute for Marine Microbiology. Her team’s research reveals why these tiny organisms are such a big concern.
The problem starts with color. Normally, ice is white and reflects sunlight back into space. But these algae are dark, turning parts of the ice surface darker. Just like how a black car gets hotter in the sun than a white one, these dark patches make the ice absorb more heat. The change is so dramatic that satellites can see these dark areas from space.
What makes these algae special is how well they survive in a place with almost no food. The research team discovered these algae are extremely good at absorbing nitrogen and storing phosphorus – nutrients they need to grow. These algae are remarkably efficient at surviving in places where nutrients are very scarce.
This matters because Greenland’s ice sheet is huge and important. When it melts, the water flows into the ocean and makes sea levels rise worldwide. The more ice that melts, the more space these algae have to grow, which then causes even more melting.
The research team made an important breakthrough: they’re the first to measure exactly how these algae get their nutrients. “Until now, there have been no measurements of how the ice algae supply themselves with nutrients,” Halbach explains. They used new, precise methods to study individual algae cells.
Recent studies have found other worrying signs. Scientists have detected changes in how the ice moves and breaks apart. The ice sheet is showing signs of increasing instability as temperatures rise.
This isn’t just about ice far away in Greenland. The research helps scientists better predict how fast sea levels will rise, which affects coastal communities worldwide. It also reveals new risks for activities in Greenland itself, where the changing ice conditions affect the stability of the surrounding landscape.
The Max Planck Institute and University of Aarhus research teams’ findings do more than just explain how algae grow on ice. They help scientists improve their climate predictions by adding these biological processes to their calculations. This gives a more accurate picture of how fast the ice might melt in the future.
These findings show how something as small as microscopic algae can affect something as big as global sea levels. While the algae are doing what comes naturally to them – growing and spreading – their simple actions add to the larger challenge of climate change.
The research appears more urgent because these algae are so good at what they do. Without something stopping them – like parasitic fungi or a lack of certain nutrients they need – they’ll likely keep spreading across the ice, wherever it’s exposed. Each new dark patch they create adds to the melting cycle.
Scientists are using these discoveries to make their predictions more accurate. By understanding exactly how these algae work, they can better estimate how much ice will melt and how fast sea levels might rise. This helps communities prepare for future changes in climate and sea level.
