Abstract

A Radiometrics MP1516A Water Vapor Profiler now operates at CFARR; it was installed during August 2007. The instrument operates continuously and provides measurements of the zenith sky brightness temperature at 21 frequencies in the range 22-30 GHz; this region of the microwave spectrum includes a water vapour absorption line. From these measurements the integrated water vapour and total liquid water at zenith are derived, together with the vertical profile of water vapour density. Due to the complex nature of the relationship between brightness temperature measurements and the processed data products, some degree of uncertainty is inevitable.