Observations of Turbulence over Minicoy with the F-type Radiosonde

Abstract

The paper discusses the F-type radiosonde ascents at Minicoy during the period May 1963 to Apri11964. It is observed that the rate of rotation of the fan remains unchanged upto about 150 mb and that it decreases above. The rotation is related to the rate of ascent of the balloon and its decrease beyond 150 mb shown to be the same or decreases due to leakage of hydrogen through balloon fabric. The regions of turbulence in the upper tropopause and stratosphere are studied from the rate of rotation of the fan. From January to March, turbulence occurs in the tropopause and stratosphere causing often the balloon to burst. This observation confirme the infcrences drawn from the blur at the end of the traces in the Dines’ meteorograph ascents. The vertical component of gusts is estimated to be between 10-20 kmph. The thickness of the region of turbulence is found to be about 4 km and the region of turbulence duping the monsoon months is in the upper troposphere below the tropopause.