Frost is a thin layer of ice on a solid surface, which forms from water vapor that deposits onto a freezing surface. Frost forms when the air contains more water vapor than it can normally hold at a specific temperature. The process is similar to the formation of dew, except it occurs below the freezing point of water typically without crossing through a liquid state.
A patch of grass showing three zones. crystalline frost in the below-freezing shade (blue, lower right) frost in the warming but still below freezing strip most recently exposed to sunlight (white, center) frost-free region: here, the previous frost has melted from a more prolonged exposure to sunlight (green, upper left.)
A spider web covered in air hoar frost
Hoar frost on the snow
Depth hoar, imaged with optical (left) and scanning electron (right) microscopy
Ice is water that is frozen into a solid state, typically forming at or below temperatures of 0 °C, 32 °F, or 273.15 K. As a naturally occurring crystalline inorganic solid with an ordered structure, ice is considered to be a mineral. Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaque bluish-white color.
An ice block, photographed at the Duluth Canal Park in Minnesota
This iceberg can stay afloat in spite of its size because it is less dense than water
So-called feather ice on the plateau near Alta, Norway. The crystals form at temperatures below −30 °C (−22 °F) and contain a lot of trapped air, making them light enough to be supported by the thin branch
Frozen waterfall in southeast New York
