Abstract
The possibility of short-time forecasting of snowfall by a Mie lidar, which can measure the depolarization ratio, is discusssed. The information which can be obtained by lidar observation on snow clouds are the integrated intensity of backscattered signal, ceiling height, information of wind velocity which is obtained from the short-time variation of signal intensity and the depolarization ratio. Among these, it was found in field studies (Yonezawa) that the time variation of the ceiling height is most useful, to forecast the beginning of snowfall. By combining lidar data which was obtained in Yonezawa and in Tokyo, it was found that the ceiling height began to drop approximately 2 hours before the snow fell when the temperature on the ground was less than 0°C. This implies that snowfall can be predicted about 2 hours in advance.
