The ocean waters can be divided into three layers, depending on their densities. Less dense waters form a top layer called the surface mixed zone. The temperature and salinity of this layer can change often because it is in direct contact with the air. For example, water evaporation could cause an increase in salinity, and a cold front could cause a drop in temperature.
There are four temperature scales that give us a relative understanding of the heat in the object or system we are measuring: Fahrenheit, Celsius, Kelvin, and (the less-common) Rankine. The Fahrenheit and Celsius scales are based on two fixed points, the Kelvin and Rankine scales are based on one.
