In this study, we conducted a domain-integrated vorticity budget analysis to quantitatively understand the developing mechanism of the Arctic Cyclone (AC) in August 2016 (AC16). The results showed that the vorticity enhancement of the AC16 was dominated by the horizontal flux convergence of vorticity at all layers with a maximum near the tropopause. The enhancement near the tropopause was characterized not only by the horizontal supply but also by the vertical transport of vorticity. In the boundary layer within the AC16, the convergence of horizontal winds and the corresponding divergence of vertical winds occurred. In addition, during the merging process, updrafts were dominant in the troposphere due to the structure of the mid-latitude cyclone. These structures caused the upward transport of vorticity to the tropopause, which is considered as an important internal process of the AC16. However, time-averaged vorticity budget during the developing stage indicated that the vertical flux term and the divergence term compensate with each other. As a result, it was concluded that the AC is excited and maintained by the merging of the vortices associated with the migrating mid-latitude cyclone and polar vortex.

在这项研究中，我们进行了领域集成的涡度预算分析，以定量地了解2016年8月（AC16）的北极旋风（AC）的发展机理。结果表明，AC16的涡度增强主要由所有层的涡度的水平通量收敛所决定，对流层顶附近的最大值。对流层顶附近的增强不仅以水平供应为特征，而且还以涡度的垂直输送为特征。在AC16的边界层中，发生了水平风的收敛和垂直风的相应发散。此外，在合并过程中，由于中纬度气旋的结构，对流层上升气流占主导。这些结构导致涡度向上输送到对流层顶，这被认为是AC16的重要内部流程。然而，在发展阶段的时间平均涡度预算表明，垂直通量项和发散项相互补偿。结果，得出结论，通过与迁移中纬度旋风分离器和极地涡旋相关的涡旋的合并，AC被激发并得以维持。