Portable lidar ceilometer for cloud-base height measurement

The algorithm of a portable lidar ceilometer for cloud-base height measurement was developed. The zero-crossing of lidar return slope was considered the location of the cloud base. Since the cloud was different from the atmosphere in random noise in the slope and intensity and pulse width of the backscatter returns, the cloud base height could be determined by analyzing the difference of lidar returns carefully. The random noise could be eliminated by detecting cloud continuously on the same location. The measured data by portable lidar ceilometer were compared with that by traditional count ceilomenter and they agreed well.