Adiabatic rate is used to describe the change in temperature as a result of the rising or the sinking of an air parcel.
Knowing that the dry adiabatic rate of change for unsaturated air is 10°C/1000 m means that the temperature of the unsaturated air parcel would increase (get warmer) as the air parcel sinks and will decrease (get cooler) as the air parcel rises.
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