Dual-doppler Radar Inversion Storm Dimensional Wind Field Numerical Simulation Study

The fully elastic three-dimensional convective storm model (IAP-CSM3D) established and developed by the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences was used to simulate a strong convective storm that occurred in the northeast of Beijing on June 29, 1996. The initial field of the model is the in situ observational data. Combining the observational data by the Doppler weather radar, the distribution and evolution of macro-physical as well as micro-physical variations such as wind field structure, radar echo structure, overhang echo, bound weak echo region, strong echo wall, water content, etc. in the storm were analyzed. Some typical features of supercell structure were revealed on the basis of the analysis. The formation mechanism of hailstones in the storm was analyzed too. The results show that the auto-conversion of frozen drops and graupels (CNfh, CNgh) are the main sources of the hailstones in the strong convective storm studied in the paper, but the contribution of frozen drops is greater than that of graupels. Hailstones mainly depend on the processes of collecting supercooled water (CLch,CLrh) to grow.The relatively simple mass continuous equation was used to calculate vertical velocity, and use radial projection relation of Dual-Doppler Radar to retrieve the case's three-dimensional wind field. Contrasting with the results of the 3-D numerical model output shows that the general trends of the retrieved wind stream field are completely coincided with the simulated ones. The central position of the storm is about on the same altitude and the upward as well as the downward stream are almost the same. The error analysis shows that the retrieved results especially the vertical velocity is satisfactory and can reflect the real three-dimensional wind field by and large. Since the central positions of the mesoscale covective systems are approximately at the height of 4-6km and the retrieved results are perfect at 5.5km height, the retrieve algorithmic method that used in the paper can be used in the research work for the future.