Abstract:
In order to better understand the hail and three-body scattering signature, improve the ability of operational warning and lay the foundation of automatic hail identification on the ground based on dual-polarization radar, a hail case observed by the S-band polarimetric radar on 20 March 2019 is used to examine the observational signature and microphysical process. The result shows that: (1) During the mature stage, the hailstorm has high echo top and strong echo area aloft that are characterized by negative
ZDR (<−0.5 dB), low
ρhv (~0.9) and negative
KDP caused by backscattering phase, indicating that hails existing within this area are reasonably identified by HCA; (2) during the period of hail falling on the ground, the reflectivity in high levels decreases, the strong echo area descends close to the ground, and
ρhv below the melting level increases, indicating that the size of ice particles falling from high levels decreases; hails fall to the ground at the time when the hails identified by HCA is decreasing; (3) the probability density distributions (PDD) of
ZH,
ρhv and (SD (
ZH)) within three-body scattering signature are similar to that in North American, and the PDD of Z
DR tends to be more negative, while the range of distribution for SD (
φDP) is about twice that in North America.