Observations of Turbulence at Delhi during the winter months - November 1966 to February 1967 with the F-type Radiosondes

Abstract

Study of turbulence at Delhi during the winter months when the westerly jets prevail was made by special F-type radiosonde ascents from November 1966 to February 1967 and in April 1967" The vertical components of gusts and their thicknesses were determined by measuring the rate of rotation of the fan from the length of complete Olland cycles which consists of 1000 impulses" Since the duration of the gust may not last as much as a full cycle, lengths of tapes for 100 impulses and 500 impulses were measured. It was then found that the duration of the gnats is only of the order of 200-300 impulses. The vertical components of the gusts were therefore larger and thicknesses smaller when the length of 100 impulses were used. One of the interesting features at Delhi was the presence of turbulence fu thin layers of air (about 1500 m thick), fu which the lapse rate was different from those in the layers above and below. These regions were above the jet stream and were between 150 and 100-mb levels.