Burj Dubai and the adiabatic lapse rate

The amount of decrease is governed by the dry adiabatic lapse rate. The reason for this decrease is as follows. When a parcel of air rises, it expands, because the pressure is lower at higher altitudes. As the air parcel expands, it pushes on the air around it, doing work; but generally it does not gain heat in exchange from its environment, because its thermal conductivity is low (such a process is called adiabatic). Since the parcel does work and gains no heat, it loses energy, and so its temperature decreases.

The formula is the following:
dT/dz = -9.8 C/Km which means approximately 1 degree Celsius drop each 100 meters of height.

However the above calculation is valid for dry atmosphere. In dubai, though sometimes in the winter it really gets dry - especially after heavy rain showers, the usual case is near 100% humidity. In this case we use the saturated adiabatic lapse rate. To save your time, here is the difference:
dT/dz = -6.5 C/Km which means 0.65 degree Celsius drop each 100 meters

In the case of Burj Dubai, at 819, the drop in temperature will be at 6-8 degrees.