Liutex for Visualization of the Tropical Cyclone Structure

Tropical cyclones are among the most destructive weather systems, causing substantial societal and economic impacts worldwide. Accurate visualization and identification of tropical cyclone vortex structures are essential for understanding their organization and evolution. In this study, the Liutex method, a vector-based vortex identification technique that separates rigid body rotation from shear, is applied to two representative Atlantic hurricanes, Teddy and Dorian. The performance of Liutex is compared with conventional vortex identification methods: vorticity, the Q criterion, and the λ2 criterion. Liutex provides clear visualization of the eye, eyewall, and rainbands, enabling intuitive identification of localized regions of rigid body rotation. Furthermore, Liutex fields suggest that the eyewall and rainbands are made up of numerous localized vortical structures in the horizontal and vertical directions rather than forming a single continuous vortex ring or line, offering a new perspective on tropical cyclone organization. These findings demonstrate the potential of Liutex as a physically meaningful diagnostic and visualization tool for investigating tropical cyclone vortex structures and other complex rotating flows.