Wind Hazard Analysis of Typhoons Approaching the Coast Based on Typhoon Size Data

Despite frequent tropical cyclone (TC) activity over the western North Pacific (WNP), scarce offshore observational data hinders precise assessment of typhoon-induced wind hazards. This study used the CMA/STI Satellite-Analyzed Tropical Cyclone Size Dataset (V3.0) to reconstruct 0.5°×0.5°gridded wind fields from 1981 to 2020, proposing the Vortex Destructiveness Index (VDI) and Grid-based Potential Destructiveness Index (PDIg) etc. to analyze spatiotemporal changes in TC activity and hazards. Results indicate:(1) TC genesis and landfall frequency declined since1980, with landfall locations shifting notably north-eastward and lifetime maximum and landfall intensities rose by ~0.8 m s⁻¹ and 3.8 m s⁻¹ post-2000 respectively.(2) Mean radii of maximum winds (Rmax) and Beaufort 8-,10-,12-winds (R8, R10, R12) were 48 km, 65 km, 100 km, 179 km, with R8 showing the strongest asymmetry. (3) Typhoon impacts and maximum winds rose at higher latitudes and mainland China, with a 0.5–0.6 probability of winds ≥32.7 m s⁻¹ from the Yangtze River estuary to southern Taiwan Strait. (4) China’s offshore 50-yr and 100-yr Return Period Wind Speeds (Vp) exceeded 45 m s⁻¹ and 50 m s⁻¹respectively，and Vp in some northern coastal cities (e.g., Wenzhou, Fuzhou) surpassed design standards. (5) VDI peaked east of Taiwan, with a secondary high off Zhejiang and the South China Sea and Pearl River Delta had significant uptrends. (6) TC structural asymmetry was most pronounced at high latitudes and nearshore, enhancing hazards in the southern semicircle off Southeast China and western semicircle off East China. (7) Despite fewer landfalls, stronger TC intensity and northward-shifted activity have heightened wind risks and potential destructiveness across northern coastal and inland regions. This study provides a scientific basis for China’s long-term disaster prevention and climate-resilient financial planning.