Question

When environmental lapse rate exceeds adiabatic lapse rate?

Answer 1

Lapse rate is the rate at which Earth's atmospheric temperature decreases with an increase in altitude, or increases with the decrease in altitude. [1][2] Lapse rate arises from the word lapse, in the sense of a gradual change.

Although this concept is most often applied to Earth's troposphere, lapse rate can be extended to any gravitationally supported parcel of gas.