When air of the atmosphere rises up,it cools. Why?

(N/A) As air rises,the atmospheric pressure decreases. Due to this decrease in pressure,the air parcel expands. Since the expansion occurs rapidly,it can be considered an adiabatic process where the air does work on the surroundings at the expense of its internal energy. According to the first law of thermodynamics,$dQ = dU + dW$. For an adiabatic process,$dQ = 0$,so $dU = -dW$. Since the air does positive work $(dW > 0)$,its internal energy decreases $(dU < 0)$,which leads to a decrease in temperature.