Sea smoke, frost smoke, or steam fog is

fog Fog is a visible aerosol consisting of tiny water droplets or ice crystals suspended in the air at or near the Earth's surface. Reprint from Fog can be considered a type of low-lying cloud usually resembling stratus, and is heavily influ ...

which is formed when very cold air moves over warmer water. Arctic sea smoke is sea smoke forming over small patches of open water in

sea ice Sea ice arises as seawater freezes. Because ice is less dense than water, it floats on the ocean's surface (as does fresh water ice, which has an even lower density). Sea ice covers about 7% of the Earth's surface and about 12% of the world's oce ...

. It forms when a light wind of very cold air mixes with a shallow layer of saturated warm air immediately above the warmer water. The warmer air is cooled beyond the dew point and can no longer hold as much water vapor, so the excess condenses out. The effect is similar to the "steam" produced over a hot bath or a hot drink, or even an exercising person. Sea smoke has a turbulent appearance and may form spiralling columns.H. U. Roll, ''Physics of the marine atmosphere'', p. 359, Academic Press, 1965 . It is usually not very high and lookouts on ships can usually see over it (but small boats may have very poor visibility)Hank Halsted, "Fog", ''Motorboating and Sailing'', pp. 41-42, August 1982 because the fog is confined to the layer of warm air above the sea. However, sea smoke columns 20–30 m (70–100 ft) high have been observed. Because this type of fog requires very low air temperatures, it is uncommon in temperate climates, but is common in the Arctic and

Antarctic The Antarctic ( or , American English also or ; commonly ) is a polar region around Earth's South Pole, opposite the Arctic region around the North Pole. The Antarctic comprises the continent of Antarctica, the Kerguelen Plateau and other ...

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