SCS-TCWave: an event-based hindcast dataset of typhoon waves and reconstructed wind fields for the South China Sea (1979–2025)

Abstract. Extreme-wave estimates for the South China Sea (SCS) depend on the peak sea states of tropical cyclones, yet reanalysis winds smooth the storm core and no openly archived, event-resolved typhoon wave record exists for the basin. We present SCS-TCWave, an event-based hindcast of the 480 tropical cyclones that reached tropical storm intensity inside the SCS during 1979–2025. Each event is forced by 10-m winds reconstructed from best-track records (a Holland-type vortex with motion asymmetry and far-field gale-radius anchoring, blended into ERA5) and simulated with SWAN on one-way nested 0.25°/0.05° grids under a frozen, fully audited configuration. Each event ships three CF-1.8 NetCDF layers: hourly wave fields, the reconstructed wind forcing, and an extreme-value catalogue of per-cell event maxima. Validation against 64,529 calibrated altimeter super-observations from 187 events shows near-zero bias in background sea states and a single-signed core overestimation that grows with intensity (+1.15 to +2.99 m within 100 km of the centre). A distance-binned multiplicative correction annex with bootstrap confidence intervals centres the per-event peak distribution: the median relative error of per-event maxima moves from +9.5 % raw to −1.4 % corrected, with 78 % of events within ±25 %. At the highest observed peak (9.4 m, Pearl River estuary, Typhoon Mangkhut) the product stays within ±25 % where an identically configured ERA5-forced run does not; beyond 400 km ERA5-based products remain preferable, and this distance-based usage rule ships with the data. Method tiers, quality flags, the frozen configuration, and the full calibration record accompany the archive (https://doi.org/10.57760/sciencedb.011ul; Fang et al., 2026).