热带气旋“天鸽”与“山竹”大气风场过程变化及结构对比分析

Tropical Cyclones “Hato” and “Mangkhut” Atmospheric Wind Field Processes Changes and Structure Comparative Analysis

本研究利用香港天文台发布的热带气旋数据库、香港各站点气象数据、多普勒雷达回波图像、天气雷达回波图像以及日本气象厅向日葵八号卫星的红外线卫星图片等资料,对严重影响华南沿岸的热带气旋“天鸽”和“山竹”的大气风场过程变化进行对比及成因分析。结果表明:“天鸽”环流紧密且能量集中,对大气风场影响范围相对较小,持续时间较短, 风速极大值较大;“山竹”环流广阔,登陆菲律宾东北部后,核心对流能量分散至气旋距离中心100~150公里,对大气风场影响范围大,持续时间长,风速极大值相对较小。造成差异的原因是,“山竹”在远洋已经发展成熟,并经过眼壁置换中心环流扩大;而“天鸽”以较低强度进入南海发展时间空间受限,但因其靠近珠三角前并未登录减弱,核心区得到进一步发展。

This study uses tropical cyclone databases released by the Hong Kong Observatory (HKO), meteorological data from various stations in Hong Kong, Doppler radar echo images, weather radar echo images, and infrared satellite images from the Japan Meteorological Agency’s Himawari-8 satellite to compare and analyze the atmospheric wind field changes of tropical cyclones “Hato” and “Mangkhut” that seriously affect the southern coast of China. The results indicate that the circulation of “Hato” is so tight and energy is concentrated with a relatively small range impact on the atmospheric wind field, a short duration, and a larger maximum wind speed. The circulation of “Mangkhut” is broad. After landing in the northeast of the Philippines, the core convective energy is dispersed 100~150 kilometers away from the center of the cyclone, which has a larger range impact on the atmospheric wind field and a long duration, but the maximum wind speed is relatively small. The reason for the difference is that “Mangkhut” has already developed and matured in the ocean, and has expanded through the central circulation of eyewall replacement;however, the development time and space of “Hato” entering the South China Sea at a lower intensity are limited, but due to it making no landfall and weakening before approaching the Pearl River Delta, the core area has further developed.