Refined Typhoon Geometric Center Derived From a High Spatiotemporal Resolution Geostationary Satellite Imaging System

GaoFen-4 (GF-4) and Himawari-8 (H8) imagery data were utilized to demonstrate and validate the impact of enhanced spatiotemporal imaging resolution when tracking Super Typhoon Nepartak (2016). The GF-4 remote sensing satellite is the China's first civilian high-resolution geostationary optical satellite, which has been launched at the end of December 2015.A classical TV-L1 optical flow (OF) algorithm and H8 cloud-top products were also presented to derive cloud-tracking motions, rotating centers, and geometric centers of Super Typhoon Nepartak to investigate the inner-core dynamics and structures of the typhoon. The typhoon positions of the rotating centers derived from the lowest velocities using GF-4 showed good agreement with centers derived using the H8 cloud-top pressure and height threshold-based method. The OF method failed to retrieve the typhoon center using H8 imagery data due to the relatively coarse spatiotemporal resolution. Conversely, refined features and shifts in the track of Typhoon Nepartak were apparent in the GF-4 imagery data as compared to H8. These findings illustrate the significant impact of a satellite imaging system with a higher spatiotemporal resolution when investigating the dynamics features of typhoon.