Z - R relation for snowfall using small Doppler radar and high sensitive snow gauges

Snowfall data was simultaneously recorded by a weather radar, two high sensitive snow gauges and an imaging system with high accuracy at short time intervals. The snowfall rate R was measured with two gauges and radar reflectivity factor Z was measured using a small bistatic X-band Doppler radar. The images of falling snow particles were used to obtain size and related parameters. Since all the measurements were located in a small area, it can be said that the obtained reference data corresponds well to radar data, and it is possible to analyze snowfall rate variations in sufficient detail for practical purposes. Snowfall was observed in Kanazawa, Japan, in the winter of 2009. A total of 22 snowfall events was extracted for type of snowflake or graupel, varying in duration from 4 to 31 minutes. These were then treated separately to calculate the coefficients of Z - R relation. The observations suggest that parameters of snow particle properties are useful to understand radar measurement.