Collaborative assessment of reflectivity consistency between FY-3G precipitation measurement radar and ground-based radars

FY-3G is the first polar-orbiting satellite equipped with a precipitation measurement radar (PMR) operating at Ku- and Ka-band frequencies in China. In this study, we compare the reflectivity data from the FY-3G PMR Ku product and ground-based radars (GRs) during 2024. And the FY-3G PMR is also used as a third-party reference to evaluate the reflectivity consistency among different GRs. The FY-3G PMR and GRs share similarities in the general distribution, characteristics, and intensity of reflectivity in strong precipitation cloud systems, though the former presents less detailed system structure. Systematic deviations between the FY-3G PMR and GRs and between GRs are comparable, albeit the reflectivity of the FY-3G PMR is generally slightly stronger than that of GRs (especially X-band GRs), with a mean bias ranging from 0.7 to 1.7 dB. S-band GRs exhibit the smallest systematic deviation (STD = 3.09 dB) from FY-3G PMR, whereas the X-band GRs show the largest (STD = 3.61 dB), indirectly indicating the highest internal consistency among S-band GRs and the lowest among X-band GRs. Besides, both S- and C-band GRs display similar deviations when paired with the FY-3G PMR as well as paired with their adjacent S/C-band GRs, suggesting good consistency between these two bands. In contrast, X-band GRs exhibit relatively poor consistency with S-band GRs and the FY-3G PMR, showing a deviation ranging from 3.0 to 4.6 dB.