Laura Halbach

Glacial algae may accelerate the melting of the Greenland Ice Sheet

Especially in West Greenland, the colour of the ice sheet has begun to change; the new, darker colour means that the ice is melting faster than usual. The same phenomenon is seen at glaciers in other parts of the world, and it is the result of i.a. microalgae, which have adapted to the glacial environment. As a PhD scholar with the Department of Environmental Science, Aarhus University, in Roskilde, arctic microbiologist Laura Halbach studied the glacial algae of which little was known at the time.

“We did not know to which extent their growth was limited by the extremely nutrient-poor environment on the ice. And no one had studied their ability to absorb nutrients or the role of their pigments in light absorption,” she explains.

Today, Laura Halbach has filled this gap. As a PhD student, she conducted field studies and i.a. examined algae samples using a secondary ion mass spectrometer – a sophisticated technique which enables the study of algae at single-cell level. Previously, no one had used the technique in this field, but it enabled Laura Halbach to perform measurements revealing that glacial algae require very few nutrients.

“These are significant findings. These algae’s ability to effectively absorb and store nutrients suggests that they – aided by global warming – will be able to colonise more ice in the future and thus potentially accelerate the melting of the ice sheet,” says Laura Halbach.

Today, she continues her work as a postdoctoral researcher. She is currently rewriting articles from her thesis and adding more findings before publication.