Originally Posted by High Wing Drifter
From what I recall, that is in the PPL Confuser, completely ignored in the Thom book and discredited by the ATPL course which teaches that the dewpoint lapse rate is quite unreliable and difficult to estimate
I think you will find it is the
environment dew point lapse rate (i.e. the figure that corresonds to the ELR) that varies massively and is thus unreliable. The
adiabatic dew point lapse rate (i.e. that relating to a rising parcel of air) is a physical constant ... given by the Met Office Handbook of Meteorology as 1.7 degC per km for unsaturated air.
But it's all a mystery to me. Where's that meteorologist, there's never one on hand when they're most needed.
