Cirrus cloud macrophysical and optical properties over north China from CALIOP measurements

Global cloud climatological studies based on active remote sensing data sets benefit from more accurate resolution of vertical structure and more reliable detection of optically thin layers. The mean values for cirrus cases over North China are 0.19±0.18 for infrared emittance, 0.41±0.68 for visible optical depth, 0.26±0.12 for integrated depolarization ratio, and 0.72±0.22 for integrated color ratio.

When studied using reasonable assumptions for the relationship between extinction and ice crystal backscatter coefficients, our results show that most of the cirrus clouds profiled using the 0.532 μm channel data stream correspond with an optical depth of less than 1.0. The dependence of cirrus cloud properties on cirrus cloud mid-cloud temperature and geometry thickness are generally similar to the results derived from the ground-based lidar, which are mainly impacted by the adiabatic process on the ice cloud content.