The Kelvin scale is typically used in laboratories dealing with extremely cold temperatures. Zero degrees Kelvin indicates absolute zero, which is the point at which molecular motion stops. The scale is named after the 1st Baron Kelvin, William Thomson (1824–1907), who was a British engineer and physicist. Thomson developed the absolute thermometric scale, which used degrees Celsius as its increments and had absolute zero being –273°C (the actual figure has now been determined at –273.15°C. Such extremes are rarely needed in meteorological studies, however.
Thermometers in the United States display both Celsius and Fahrenheit temperatures, which saves people the trouble of having to convert degrees.