Hoarfrost

(Redirected from Hoar frost)

Categories: Forms of water

Hoarfrost refers to the white ice crystals, deposited on the ground or exposed objects, that form when the air is moist and surface is cold. Hoarfrost is often seen on cold, clear autumn nights.

Distinction between hoarfrost and rime ice is that in formation of hoarfrost, the water vapour condenses through deposition directly to solid ice, while the rime ice is formed following initial condensation into liquid droplets. Thus, hoarfrost is formed when the dew point 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 Image:DSCN2716.jpg Image:DSCN2647.jpg