Arid Zone Research ›› 2024, Vol. 41 ›› Issue (2): 200-210.doi: 10.13866/j.azr.2024.02.03

• Weather and Climate • Previous Articles     Next Articles

Observational analysis of a hailstorm event in Northeast Qinghai

WANG Qihua1(), LIN Chunying1(), LIU Xiao2, ZHANG Liyan1, ZHAO Zhanxiu3, ZHANG Boyue1, GONG Jing1   

  1. 1. Weather Modification Office of Qinghai Province, Xining 810001, Qinghai, China
    2. Shanxi Artificial Precipitation Enhancement and Lightning Protection Technical Center, Taiyuan 030032, Shanxi, China
    3. Haibei Meteorological Bureau, Haiyan 812200, Qinghai, China
  • Received:2023-03-24 Revised:2023-11-07 Online:2024-02-15 Published:2024-03-11

Abstract:

The Northeast of Qinghai Province is the key area for crop production and but is highly susceptible to hail. Hail forecasting, early warning, and artificial anti-hail operations are crucial strategies for reducing hail disasters. Understanding the features of hail monitoring data is fundamental to improving hail forecasting capabilities and initiating timely performing hail suppression measures. The hailstorm occurrence on June 29, 2021, Northeast of Qinghai, was analyzed using Doppler radar data, raindrop spectrum data, and high and ground data. The results revealed extreme unstable atmosphere stratification due to cold advection transportation at the upper levels, coupled with obvious temperature increases on the ground in this region, which is the weather background of this hailstorm process. During the hailstorm, the average raindrop spectrum and velocity spectrum at Pingan Station exhibited multipeak distribution. Differences between the maximum diameter of the Pingan hailstorm observed artificially and the raindrop spectrometer were insignificant, indicating the raindrop spectrometer’s efficacy in observing hail particles and determining the time of maximum hail occurrence. The developmental stages of the hail cloud were identified, encompassing occurrence, jump, hail formation, and extinction. There was an obvious “V” shaped inflow gap in the low-level radar reflectivity factor before the hail. In the mature stage, the hail cloud displayed a noticeable bounded weak echo area, with obvious southerly inflow in the middle and lower layers. The radial velocity map depicted a discernible “0 line” in the hail cloud, pointing vertically upward through the overhanging echo and bounded weak echo region, indicating the top of the hail cloud. The research results have important guiding significance for hail forecasting Northeast of Qinghai. Moreover, the characteristics of various elements preceding hail occurrence serve as important criteria for scientifically identifying sites and conducting timely and appropriate artificial hail suppression operations.

Key words: hail, raindrop spectrum characteristics, echo characteristics, observation and analysis, Northeast of Qinghai