Abstract:Ice nuclei concentration in the atmosphere is measured by both the Bigg mixing cloud chamber and the static diffusion chamber of processing Millipore filter samples at northwest suburb of Beijing from 18 March to 30 April 1995. The typical weather of clear sky,sandstorm,and heavy air pollution were encountered during these parallel observation. The data were obtained by mixing cloud chamber for -15℃,-20℃,-25℃ and -30℃. 464 membranes sampled processed in the static diffusion chamber at -20℃ and -25℃ respectively under ice super-saturation condition. The data obtained from both devices was compared daily and the correlation with wind direction,surface visibility and atmospheric pressure is also analyzed.