Physical Process Contributions to the Development of a Super Explosive Cyclone Over the Gulf Stream

Frontiers in Earth Science

Chunlei Liu¹  Jianjun Xu¹  Yufeng Xue¹  Shuqin Zhang¹  Ruoying Tang²  Hongfei Mao³  Zhuoqiang Guan⁴  Yanzhu Zheng⁴  Zhefan Huang⁴  Shaojing Zhang⁶ 

[1] CMA-GDOU Joint Laboratory for Marine Meteorology, Zhanjiang, China;College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, China;College of Ocean Engineering, Guangdong Ocean University, Zhanjiang, China;College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, China;Key Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Guangdong Ocean University, Zhanjiang, China;South China Sea Institute of Marine Meteorology, Guangdong Ocean University, Zhanjiang, China;

关键词: super explosive cyclone;    Gulf Stream;    structure;    diagnostic analysis;    physical process;   

DOI  :  10.3389/feart.2021.722555

来源: DOAJ

【 摘 要 】

Contributions of different physical processes to the development of a super explosive cyclone (SEC) migrating over the Gulf Stream with the maximum deepening rate of 3.45 Bergeron were investigated using the ERA5 atmospheric reanalysis from European Centre for Medium-Range Weather Forecasts (ECMWF). The evolution of the SEC resembled the Shapiro-Keyser model. The moisture transported to the bent-back front by easterlies from Gulf Stream favored precipitation and enhanced the latent heat release. The bent-back front and warm front were dominated by the water vapor convergence in the mid-low troposphere, the cyclonic-vorticity advection in the mid-upper troposphere and the divergence in the upper troposphere. These factors favored the rapid development of the SEC, but their contributions showed significant differences during the explosive-developing stage. The diagnostic results based on the Zwack-Okossi equation suggested that the early explosive development of the SEC was mainly forced by the diabatic heating in the mid-low troposphere. From the early explosive-developing moment to maximum-deepening-rate moment, the diabatic heating, warm-air advection and cyclonic-vorticity advection were all enhanced significantly, their combination forced the most explosive development, and the diabatic heating had the biggest contribution, followed by the warm-air advection and cyclonic-vorticity advection, which is different from the previous studies of ECs over the Northwestern Atlantic. The cross section of these factors suggested that during the rapid development, the cyclonic-vorticity advection was distributed and enhanced significantly in the mid-low troposphere, the warm-air advection was strengthened significantly in the mid-low and upper troposphere, and the diabatic heating was distributed in the middle troposphere.

【 授权许可】

Unknown