INVESTIGATION OF REFRACTOMETER MEASUREMENTS IN THE ATMOSPHERE AT HIGH RELATIVE HUMIDITIES AND TEMPERATURES

摘要

Two techniques for the precise measurement of changes in air refractivity within the troposphere are examined in the present study. These are the microwave refract meter which uses a ventilated metal cavity as the sensing element, and the Hay refract meter whose sensing element is an air capacitor. The effects of water vapour adsorption and condensation upon the sensing elements of these instruments at high relative humidities make the interpretation of such soundings uncertain, in view of the conflicting evidence of previous workers. This report describes a laboratory study of the interaction between the refract meter sensors and the air humidity.