Studies and Developments of Meteorological Instruments for Cloud Physics and Micrometeorology (III)

New Instrument for Measurement of Wind Direction in Light Air

Abstract

A new instrument was designed for measuring the wind direction in light air. Four hot wire sensors are placed each at one of the cardinal points based on the principle of the hot wire anemometer. The wind direction is indicated as one of the eight directions. The instrument can be used for wind speeds down to 15 cm/sec. Some preliminary measurements using this instrument were made in connection with cloud physical observation of river fog.