Potential temperature

The potential temperature of a parcel of fluid at pressure ${\displaystyle P}$ is the temperature that the parcel would acquire if adiabatically brought to a standard reference pressure ${\displaystyle P_{0}}$, usually 1000 millibars. The potential temperature is denoted ${\displaystyle \theta }$ and, for air, is often given by

where ${\displaystyle T}$ is the current absolute temperature (in K) of the parcel, ${\displaystyle R}$ is the gas constant of air, and ${\displaystyle c_{p}}$ is the specific heat capacity at a constant pressure. ${\displaystyle R/c_{p}=0.286}$ for air (meteorology).

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