Partitioning Ice Water Content from Retrievals and Its Application in Model Comparison

AbstractRetrieved bulk microphysics from the remote sensing observations is a composite of ice, snow and graupel in the three-species ice-phase bulk microphysics parameterization. In this study we use the density thresholds to partition the retrieved ice particle size distribution (PSD) into small, median and large particle size modes from the millimeter cloud Radar (MMCR) observation at the tropics and the global CloudSat and CALIPSO (2C-ICE) observation. It shows that the small mode can contribute to more than 60% of the total ice water content (IWC) above 12 km (colder than 220 K). Below that, dominant small mode transits to dominant median mode. The large mode contributes to less than 10-20% at all height levels. The PSD assumption in retrieval may cause about 10% error in the IWC partition ratio. The lidar only region in 2C-ICE is dominated by the small mode, while the median mode dominates the radar only region.For the three-species ice-phase bulk microphysics parameterizations, the cloud ice mass m...