A vocabulary of landscape — a landscape of words
1133 entries
cryoconite
Cryoconite is the dark dust that collects on the surface of a glacier: rock flour, soot, pollen, and windblown grit, bound together by bacteria and algae growing in it. Because it is dark, it absorbs sunlight and melts down into the ice, drilling a small vertical shaft that fills with meltwater. These cryoconite holes are round, sometimes a foot deep, and they hold a functioning ecosystem of bacteria, algae, rotifers, and tardigrades.
Etymology
The word is Greek for cold-dust and was coined by the Swedish explorer Adolf Erik Nordenskiöld, who noticed the material on the Greenland ice sheet in 1870 and thought it might be cosmic in origin. He was wrong about the source, which is mostly terrestrial, but the name stuck and so did the question of why an ice sheet is dirtier than it looks.
Notes
Cryoconite holes are among the simplest complete ecosystems on earth, small enough to be studied entire, which is why microbiologists work on them. The organisms living in them are extremophiles that freeze solid and return. Because the dust darkens the surface, cryoconite is also a significant control on how fast an ice surface melts in summer.