Pseudoadiabatic lapse rate

pseudoadiabatic lapse rate

The rate of decrease of temperature with height of a parcel undergoing a pseudoadiabatic process.

It is given by

where Γ_ps is the pseudoadiabatic lapse rate, g is gravitational acceleration, r_v is the mixing ratio of water vapor, c_pd and c_pv are the specific heats at constant pressure of dry air and water vapor, L_v is the latent heat of vaporization, R is the dry air gas constant, ε ≈ 0.62 is the ratio of the gas constants of dry air and water vapor, and T is temperature. The above lapse rate is usually within 1 percent of those shown under moist-adiabatic lapse rate and reversible moist-adiabatic lapse rate.

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