Examining the CRTM with its New Radar Module

In their paper published in Atmospheric Measurement Techniques, CISESS Scientist Isaac Moradi and coauthors at NASA and NOAA examine how well the Community Radiative Transfer Model (CRTM) performs for different radar frequencies now that a radar module is included in this RTM. The CRTM is commonly used in the assimilation of satellite observations within numerical weather prediction (NWP) systems. EarthCARE Cloud Profiling Radar (CPR), Global Precipitation Measurement Dual-Frequency Precipitation Radar, and CloudSat CPR observations were used in their analyses, with a focus on the sensitivity of different frequencies to hydrometeor type and the impact of particle size distributions (PSDs) and hydrometeor shape assumptions on simulated radar reflectivities.

The authors show that overall, the choice of PSD and particle shape, especially snow particle habits, largely influence simulated reflectivities. They plan to cover more hydrometeor types like hail and graupel in future analyses and to determine observation errors for the assimilation of spaceborne radar observations in NWP models.