An Audio-Modulated Tethersonde for Detailed Micrometeorological Soundings

Abstract

A tethered sonde for obtaining detailed micrometeorological soundings in the lower 500 m of the atmosphere is described. The instrument was developed to be directly compatible with the current audio-modulated radiosonde used extensively in North America; the radiosonde thermistor and hygristor are employed to measure temperature and humidity, but with a higher degree of sensitivity. A sensitive pressure transducer was specially designed to provide accurate height measurements, and sensor sequencing is accomplished by a miniature servo-switching system. Techniques of data telemetry, automatic recording and computation are very similar to those of the radiosonde system, and ancillary sensors can be adapted readily for special sounding requirements. The system is very convenient to operate, and flights made thus far have shown excellent detail in temperature and humidity profiles.