cryoconite holes

Noun

cryoconite hole (plural cryoconite holes)

1. a hollow or pond formed in a layer of snow or ice, commonly on the surface of a glacier or in polar regions, where a dark patch of cryoconite absorbs sunlight, generating heat so that it melts its way into the white, reflective ice.
   • ...cryoconite holes, thick ice covered lakes, nunataks, and subglacial environments may have played a role as refuges for microorganisms and other biota during periods of glaciation and therefore favoured the development of endemic species.2006, Joseph Seckbach, Life as We Know It, →ISBN