Observations of a glaciating hole-punch cloud

Remote-sensing measurements of a hole-punch cloud or fall-streak hole are presented. The cloud was observed with a vertically pointing infrared ceilometer, Doppler lidar, sky camera and a polarimetric radar inclined at 45 degrees. The Doppler lidar and polarimetric radar observations show that the aircraft-induced fall streak was composed primarily of oriented thick plate crystals, and the vertical Doppler velocities suggest that vertical mixing may have been triggered by the large flux of ice into the dry air at the base of the virga.