Norwegian scientists have discovered a “dark” zone on the ice sheet in Greenland, which is formed by a layer of dust and soot. The ice melts rapidly in the zone, which affects sea level rise and creates the possibility of flooding vast coastal areas around the world.
“Dark” reaches 400 kilometers in length, its maximum width is 100 kilometers. On its territory grow dark-colored algae, which feed on carbon particles, and give the ice a characteristic shade.
As a result, albedo decreases – the ability of the surface to reflect the sun’s rays. Instead, ice absorbs energy and begins to melt quickly.
Liquid water, in turn, promotes the growth of algae. Even a slight warming leads to an explosion of their numbers, as a result, the area of the “dark zone” is growing. Because of this, the reverse positive feedback effect occurs, which is further enhanced by melting.
Scientists have found that the greatest contribution to reducing ice volume is made by soot from forest fires and other combustion processes. It is responsible for 73 percent of the albedo variability.