基于双偏振雷达资料对南海弱台风降水 微物理结构的分析.

When some weak typhoons from the South China Sea land in Guangdong, they cause long-term and large-scale wind and rain disasters to the local area due to their complicated paths and slow movement. This paper uses dual polarization radar data to analyze the microphysical structure of precipitation induced by weak typhoons that came from the South China Sea and landed in Guangdong during 2018—2020. It is found that there were two main areas of strong precipitation before the landing of weak typhoons from the South China Sea. One, on the sea and south to the typhoon center, was the precipitation area of the typhoon eye wall and the other, on the right front of the typhoon’s moving direction, was located in the region where the spiral rain bands landed. In the eye wall, the large value areas of horizontal reflectivity (ZH) and differential propagation phase shift (KDP) were in the same phase in the lower levels, and the large value areas of differential reflectivity (ZDR) were located in the upwind direction. The precipitation particles started to be excited on the right side of the movement. The large concentration of small precipitation particles was distributed from the right side to the right front of the movement, while large-particle precipitation appeared on the right side and in the rear right region. In addition, typhoon precipitation particles were significantly different when they were over the ocean and the land. Due to terrain friction and uplift, the concentration of precipitation particles over the land was relatively large, but the water vapor and energy supply was insufficient, and the diameter of precipitation particle was small. Nevertheless, the sea surface had sufficient water vapor and energy supply, and the convection height was relatively high. The precipitation over the ocean was mainly composed of convective precipitation of heavy raindrops, but the concentration of precipitation particles was lower than that of land. [ABSTRACT FROM AUTHOR]