Description

Calculate the pressure of the lifting condensation level from surface temperature, dew point, and pressure. \(w\) is the mixing ratio, \(\theta\) is the potential temperature, \(t_{mr}\) is the temperature of saturated air, and \(t_{dry}\) is the temperature of dry air.

Formula

$$ w = w (dp, p) \\ \theta = \theta (t, p) \\ test = 1.0 \\ p_{lcl} = p $$

while \(test\) is not between -0.01 and 0.01, recalculate \(test\) and \(p_{lcl}\):

$$ test = t_{mr} (p_{lcl}, w) - t_{dry} (\theta, p_{lcl})\\ p_{lcl} = 2.0^{0.02test} $$

Source

Comment in function says “adapted from Carl Mohr’s RSANAL program”, which I haven’t yet found a reference to.


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Tags: formulas