metpy.calc.sigma_to_pressure(sigma, psfc, ptop)[source]

Calculate pressure from sigma values.

  • sigma (ndarray) – The sigma levels to be converted to pressure levels.
  • psfc (pint.Quantity) – The surface pressure value.
  • ptop (pint.Quantity) – The pressure value at the top of the model domain.

pint.Quantity – The pressure values at the given sigma levels.


Sigma definition adapted from [Philips1957].

\[p = \sigma * (p_{sfc} - p_{top}) + p_{top}\]
  • \(p\) is pressure at a given sigma level
  • \(\sigma\) is non-dimensional, scaled pressure
  • \(p_{sfc}\) is pressure at the surface or model floor
  • \(p_{top}\) is pressure at the top of the model domain