Exner function

The Exner function is an important parameter in atmospheric modeling. The Exner function can be viewed as non-dimensionalized pressure and can be defined as:

where ${\displaystyle p_{0}}$ is a standard reference surface pressure, usually taken as 1000 hPa; ${\displaystyle R_{d}}$ is the gas constant for dry air; ${\displaystyle c_{p}}$ is the heat capacity of dry air at constant pressure; ${\displaystyle T}$ is the absolute temperature; and ${\displaystyle \theta }$ is the potential temperature.

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