Characteristic analysis of early spring hail in Chengdu based on S-band polarization radar
In order to better carry out the monitoring,forecasting and early warning of hail weather in Chengdu,the characteristics of dual-polarization parameters of hail in early spring in Chengdu were studied by using the S-band dual-polarization radar detection of Chengdu,combined with the regional automatic weather station and conventional observation data.The fine structure of hail cloud was analyzed and compared with the short-term heavy precipitation in early spring of the same year.The results show that under the dy-namic condition of strong ascending motion formed by the coupling of the high and lower-level jets,the high-level cold advection com-bined with the surface cold air jointly triggered the hail weather of Chengdu"3·16".At the maturity stage,the central reflectivity factor(ZH)of hail cloud was more than 70 dBZ and there were obvious overhanging strong echo.Besides,the differential reflectivity(ZDR)and correlation coefficient(CC)of hail cloud were concentrated in-2-1 dB and 0.8-0.95,respectively,accompanied by specific differential phase shift rate(KDP)hole and CC valley structure in front of the cloud,and there was a typical ZDR column near strong updraft.With the weakening of the ascending motion,the ZDR large value area decreases with distance appeares in front of hail cloud,while CC shows in-creasing trend.Compared to hail cloud,the ZH of heavy precipitation convective cloud was smaller,while the ZDR and CC were signifi-cantly larger,and there was no overhanging strong echo and obvious ZDR column in front of the convective cloud.
NETL
NSTL
万方数据
