Validation of SWOT significant wave height against in situ and model observations on the northeastern Brazilian continental shelf

Resumo

The ability of the SWOT (Surface Water and Ocean Topography) satellite-derived significant wave height (SWH) estimates to represent conditions on the continental shelf of the Abrolhos Archipelago was assessed using an AWAC as the reference dataset; WAVEWATCH-III (WW3) was used as an auxiliary numerical field for spatial context. By collocating observations in space and time and applying standard statistical metrics, a high consistency between SWOT and AWAC was revealed (R ≈ 0.90; RMSE ≈ 0.25 m), with a small positive mean bias. Agreement with WW3 was likewise robust (R ≈ 0.88), indicating that the wave patterns observed by SWOT are physically consistent with the broader regional wave field represented by the numerical model. SWOT adequately represented temporal variability (including higher-energy events), although a slight overestimation tendency was detected. Overall, these findings indicate that SWOT-derived SWH reliably represents wave dynamics on the continental shelf when evaluated against in situ observations. The agreement with WW3 further supports the regional coherence of the satellite-derived wave field, reinforcing its applicability to coastal studies.