Wind Hazard Analysis of Typhoons Approaching Coastal China Based on the Typhoon Size Data
摘要
Despite frequent tropical cyclone (TC) activity over the western North Pacific (WNP), scarce offshore observational data hinder precise assessment of TC-induced wind hazards. This study used the Satellite-Analyzed Tropical Cyclone Size Dataset (V3.0), developed by the Shanghai Typhoon Institute of China Meteorological Administration (CMA/STI), to reconstruct 0.5° × 0.5° gridded wind fields from 1981 to 2020, and a vortex destructiveness index (VDI) and grid-based potential destructiveness index (PDIg) were proposed to analyze spatiotemporal changes in TC activities and hazards. The main findings are as follows: (1) TC genesis and landfall frequency have declined since 1980, with landfall locations shifting notably north-eastward, and lifetime maximum and landfall intensities rising by ∼0.8 and 3.8 m s−1 after 2000, respectively. (2) Mean radii of maximum winds (Rmax) and Beaufort scale winds of grades 8, 10, and 12 (R8, R10, R12) were 48, 179, 100, and 65 km, with R8 exhibiting the most pronounced asymmetry. (3) TC impacts and maximum winds rose at higher latitudes and the Chinese mainland, 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- and 100-yr return period wind speeds (Vp) exceeded 45 and 50 m s−1, respectively, and Vp in some southern coastal cities (e.g., Wenzhou and Fuzhou) exceeded engineering design criteria. (5) VDI peaked east of Taiwan Island, with a secondary high off Zhejiang, while the South China Sea and Pearl River Delta exhibited 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. These findings provide a scientific basis for China’s long-term disaster prevention and climate-resilient financial planning.