Hoar frost
From Biocrawler, the free encyclopedia.
(Redirected from Hoarfrost)
Hoar frost refers to the white ice crystals, deposited on the ground or exposed objects, that form when the air is moist and surface is cold. Hoar frost is often seen on cold, clear autumn nights.
Distinction between hoar frost and rime ice is that in formation of hoar frost, the water vapour condenses through deposition directly to solid ice, while the rime ice is formed following initial condensation into liquid droplets. Thus, hoar frost is formed when the dewpoint is warmer than surface but colder than the air temperature, and colder than freezing point.
The opposite of sublimation is deposition. The formation of frost is an example of meterological deposition.fi:Kuura nl:Rijp
