Microbes are pushing glacial snow into the red.
An alga species that grows on glaciers gives the snow a crimson hue, which increases the amount of sunlight that the snow soaks up and makes it melt faster, new measurements confirm. On Alaska’s Harding Icefield, these microbes are responsible for about a sixth of the snowmelt in algae-tinged areas, researchers report September 18 in Nature Geoscience. The finding suggests that future climate simulations, unlike current ones, should account for the effects of these algae when making predictions about glacial melt.