lifted_condensation_level

lifted_condensation_level(t, td, p)

Computes the Lifted Condensation Level (LCL) for a parcel ascending from a given temperature, dewpoint and pressure.

Parameters

• t (number, ndarray or Fieldset) – initial temperature (K)

• td (number, ndarray or Fieldset) – initial dew point temperature (K)

• p (number, ndarray or Fieldset) – initial pressure (Pa)

Return type

dict or None

The LCL is the level where the parcel becomes saturated during an adiabatic ascend. First, the LCL temperature is computed with the formula from [Bolton1980]:

\[t_{LCL} = 56.0 + \frac{1}{\frac{1}{td - 56} + \frac{log(\frac{t}{td})}{800}}\]

Then the LCL pressure is computed from \(t_{LCL}\) using the dry adiabatic equations.

The result is a dict with two members: “t” and “p”, containing the temperature and pressure of the LCL, in K and Pa units, respectively. On error or if the LCL does not exist None is returned.