南京大学学报（自然科学版）2025，Vol.61Issue(3)：409-424,16.DOI:10.13232/j.cnki.jnju.2025.03.006
台风"利奇马"(2019)发展演变过程的等熵分析
Isentropic analysis on the development and evolution of typhoon Lekima(2019)
摘要
Abstract
Isentropic analysis is a method that distinguishes high-entropy ascending air masses from low-entropy descending air masses through equivalent potential temperature(θe),effectively revealing the thermodynamic and dynamic structural characteristics of the atmosphere.In this study,we conducted high-resolution numerical simulations of the 2019 Northwest Pacific Super Typhoon Lekima using the fully compressible mesoscale numerical model(WRF V4.0)and analyzed the evolution characteristics of Lekima within the isentropic framework based on the simulation data.It has been found that the isentropic framework can effectively reflect the formation of the upper-level warm-core structure during the rapid intensification(RI)phase of Lekima,the significant decrease in relative humidity in the eye region,and the corresponding ascending motions in the primary and secondary eyewalls during the formation of concentric eyewalls.These findings indicate that the isentropic framework can capture the key structural changes during the rapid intensification and eyewall replacement processes of typhoons.Compared to the physical coordinate system,its advantage lies in not requiring the prior determination of the typhoon's center position.Based on isentropic analysis,this study further examined the energetics characteristics during the development and evolution of Lekima.The ability of Lekima to extract energy from the ocean and its corresponding heat engine efficiency gradually increased during its development and intensification,reaching a peak during the RI phase.Although it slightly declined during the eyewall replacement process,it remained at a relatively high level.This suggested that Lekima efficiently converted latent heat into mechanical energy during its rapid intensification and eyewall replacement processes,sustaining its intense dynamical structure.关键词
台风/双眼墙/等熵分析/能量循环Key words
typhoon/concentric eyewall/isentropic analysis/energy cycle分类
天文与地球科学引用本文复制引用
莫彩娟,王晨迪,方娟..台风"利奇马"(2019)发展演变过程的等熵分析[J].南京大学学报（自然科学版）,2025,61(3):409-424,16.基金项目
国家自然科学基金(42175004) （42175004）
