1 Answers
The potential temperature of a parcel of fluid at pressure P {\displaystyle P} is the temperature that the parcel would attain if adiabatically brought to a standard reference pressure P 0 {\displaystyle P_{0}} , usually 1,000 hPa. The potential temperature is denoted θ {\displaystyle \theta } and, for a gas well-approximated as ideal, is given by
where T {\displaystyle T} is the current absolute temperature of the parcel, R {\displaystyle R} is the gas constant of air, and c p {\displaystyle c_{p}} is the specific heat capacity at a constant pressure. R / c p = 0.286 {\displaystyle R/c_{p}=0.286} for air.