CRPh - Convective Rainfall rate from Cloud Physical Properties

        CRPh product, which is available in the NWCSAF software package from version 2013, estimates rain rates fron convective clouds

        through cloud top microphysical information.

        Cloud top microphysical parameters used by CRPh are:

        Phase

                This is an example of a Phase image:

        Effective Radius (R_eff)

The effective radius is defined as the ratio of the third to second moments of the droplet size distribution.

Where N(r) is the concentration of particles having radius r.

        Cloud Optical Thickness (COT)

Cloud optical thickness depends on the moisture density as well as the vertical thickness of the cloud. The higher is the COT, the higher is the possibility of occurrence of rain formation processes.

        Using R_eff and COT, Cloud Water Path is computed (CWP):

        This is an example of the CRPh image for the same case:

               

The case showed in this example took place on 22 of August 2008 at 14:00 UTC.

The following image shows the PPI-Radar product for the same example: