Cryoconite

Cryoconite is a fine, usually dark material found on glacier surfaces worldwide. The mineral matter on glaciers originates from local (moraines, mountain slopes) and distant sources (Saharan dust, volcanic ash). Organic matter is delivered from external sources (e.g. by wind from tundra) and produced in-situ by photoautotrophic organisms. The term cryoconite originates from ancient Greek and combines two words: κρύος – cold and κόνις – dust. It was first introduced by the Finnish-Swedish explorer Adolf Erik Nordenskiöld during the exploration of Greenland interior in 1870, at the time sediment was inspected and described by the author as a little, granular structure on the glacier. Cryoconite is represented by various morphological micro-forms including loose and granular structures. Oscillatorialean cyanobacteria can form granules from mineral substrate. Cryoconite reduces albedo of the glacier surface and speeds up ice melting, act as biodiversity hotspots of microbial communities, constitute one of the organic matter reservoir on glaciers, and are a feeder for micrometazoans. Cryoconite by reducing albedo influences the formation of cryoconite holes.