A new 278 GHz ground-based radiometer for vertical profile sounding of ClO and O3 in the upper atmosphere

This paper describes the new radiometer system operating in the 278 GHz range, which is intended for long term ground-based monitoring of the vertical profiles of chlorine monoxide and ozone in the stratosphere over the Arctic area. To improve the measurement of weak lines, in particular in view of their diurnal variation and to allow operation over a wider range of weather conditions, an advanced balancing technique has been implemented. Results of recent measurements during February and March 1996 at Kiruna, Sweden, are presented