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J. Barat

Abstract

A new high-resolution ionic anemometer was constructed using inexpensive electronics. Calibration and data procedures are outlined and preliminary results of field trials are given. The detection limit is better than 10−2 m s−1 and the frequency response ranges up to 400 Hz. The overall absolute accuracy of ±5% is constant in the 1-13 m s−1 range.

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J. Barat and P. Aimedieu

Abstract

Using a high-resolution stratospheric ozonometer it has been possible to obtain vertical ozone profiles in which microfluctuations may be interpreted as the consequence of eddy diffusion. Applying Kolmogoroff's theory to the signal, one can deduce values of the main parameters of stratospheric turbulence.

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Jean Barat and J. C. Genie

Abstract

Balloon-borne instrumentation for the measurement of three-dimensional air motion is described. Through the use of relative wind and static pressure, accurate wind profiles are obtained from the ground up to the stratosphere. The vertical resolution is between 100 and 200 m and perturbations with amplitudes of 1 m s−1 can be detected. Flight test results are given.

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J. Barat, C. Cot, and C. Sidi

Abstract

In this paper we analyze the feasibility of turbulence measurements below a rising balloon. From a typical case study we show the ability of the helisonde, hung below a large diameter balloon, to resolve the vertical profile of the dissipation rate in the troposphere and stratosphere. We examine the potential effect of the balloon wake, and the results emphasize the importance of a wind shear measurement in order to interpret properly the basic data.

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