A comparison of temperatures from mountaintops and the free atmosphere - their diurnal variation and mean difference.

Abstract

The diurnal temperature variation at the 850, 700 and 500 mb levels is evaluated using radiosonde data gathered at short time intervals in the Alpine region and is found to be very close to sinusoidal. The amplitude is of the order of 1oC and decreases with height. Mean temperature differences between mountaintops and the free atmosphere are found to be less than 1oC; they are clearly influenced by the wind at the mountaintop. -from Authors