Effects of particle shape on mass flux measurement of drifting snow by snow particle counter

Evaluation of the FlowCapt Acoustic Sensor for the Aeolian Transport of Snow

“…Both fluxes recorded by the two instruments agree considerably for fluxes close to the surface (,0.5 m) and with wind speed below 12 m s 21 (Sato et al 1993). The SPC has also been compared to two types of nets in a climatic wind tunnel.…”

“…Second, during precipitation, measurement errors may occur. On the one hand, the SPC may overestimate the snow particle density compared to precipitating snowflake density, and so it may overestimate the integrated flux: in wind tunnel experiments, the ratio of the snow mass flux obtained by an SPC on the snow mass flux obtained by a net was 2.6 for dendritic particles (Sato et al 2005). On the other hand, particles with an equivalent diameter above 500 mm will have an underestimated volume (it should be remembered that if the diameter of a snow particle is greater than the maximum diameter class-i.e., 500 mm-then the snow particle is considered to have a diameter of 500 mm), and so it may underestimate the integrated flux.…”

“…The sensor is described in detail in Sato et al (1993). The technique is based on the strong absorption of the infrared light by the snow.…”

“…In this study S i is equal to 1, assuming spherical snow particles. Sato et al (2005) estimate the theoretical snow mass flux values with different particle shapes. It was shown and confirmed by experiments that the mass flux tends to be overestimated by the SPC-S7 as the degree of nonsphericity increases for spheroidlike particles and when square-pillar-like particles become thinner or elongated.…”

“…It was shown and confirmed by experiments that the mass flux tends to be overestimated by the SPC-S7 as the degree of nonsphericity increases for spheroidlike particles and when square-pillar-like particles become thinner or elongated. To take this effect into account, a formulation for S i has been proposed (Sato et al 2005).…”