Kelvin Temperature Scale
A temperature scale with the freezing point of +273°K (Kelvin) and the boiling point of +373° K. It is used primarily for scientific purposes. Also known as the Absolute Temperature Scale. Proposed in 1848 by William T. Kelvin, 1st Baron of Largs (1824-1907), Irish-born Scottish physicist and mathematician.
Temperature
The measure of molecular motion or the degree of heat of a substance. It is measured on an arbitrary scale from absolute zero, where the molecules theoretically stop moving. It is also the degree of hotness or coldness. In surface observations, it refers primarily to the free air or ambient temperature close to the surface of the earth.
Freezing Point / Freeze
The process of changing a liquid to a solid. The temperature at which a liquid solidifies under any given set of conditions. Pure water under atmospheric pressure freezes at 0°C or 32°F. It is the opposite of fusion. In oceanography, the freezing point of water is depressed with increasing salinity.
Boiling Point
The temperature at which a liquid changes to a vaporous state. The temperature at which the equilibrium vapor pressure between a liquid and its vapor is equal to the external pressure on the liquid. The boiling point of pure water at standard pressure is 100°C or 212°F.
Absolute Temperature Scale
A temperature scale with a freezing point of +273°K (Kelvin) and a boiling point of +373°K.