Instead of being covered with pristine white snow, Alps Glaciers in France are sometimes stained with ‘glacier blood’ or red stains. These dark red blotches in the snow that look like blood are caused by mysterious microalgae organisms. Recently, a group of researchers in Grenoble, France undertook project AlpAlga to study the red snow in the mountains 3,280 to 9,842 feet (1,000 to 3,000 meters) above sea level. The project has been undertaken to examine the ill effects of climate change.
Much like the microalgae that live in oceans, lakes, and rivers, these organisms form the very basis of the food web in the mountainous ecosystem too. And they react to pollution and climate change in a similar way as in any other ecosystem. The algae that turn snow red are actually green algae, said Eric Maréchal, a coordinator of the AlpAlga consortium and director of the Laboratory of Cellular and Plant Physiology, a research facility in Grenoble, France.
Along with chlorophyll, microalgae contain carotenoids, the orange or red pigment that acts as antioxidants. Much like shields, the red or orange pigment covers the algae and protects them from the damaging effects of intense light and ultraviolet radiations. Although scientists are well aware of the glacier blood phenomena, mysteries related to these organisms still remain to unravel.
Through the project AlpaAlga, researchers are now examining the organisms to understand if they could be the biomarker for climate change. “The algae are probably markers of climate change," Marechal told LiveScience before adding that the microalgae growth reflects the rising carbon dioxide levels and related changes in the environment.
Most recently, the team studied the microalgae species at five different sites in the French Alps – Chamrousse, Loriaz, Anterne, Ristolas and Vieux Chaillol. In 2016, they collected DNA samples from surrounding sites to have a better understanding of the type of algae that grow at different alleviations and the environmental conditions specific for them to thrive in.
In the next expedition, the team of researchers will examine how the blooms change throughout the season and will also analyse both white and ‘red’ snow to find the conditions that cause these blooms. Through these studies, the scientists hope to unravel the mysteries of glacier blood and how the ecosystem on mountains changes when the climate warms.