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

Yuri Onça Prestes; Alex Costa Silva; Ramilla Vieira de Assunção; Gabriel D'annunzio Gomes Junior; Marcus Silva; Aouf Lotfi; Angelo Lemos; Fabrice Hernandez

doi:10.1590/2675-2824074.25257

##article.authors##

Yuri Onça Prestes Federal University of Pernambuco https://orcid.org/0000-0002-2065-8403
- Conceptualization
- Investigation
- Methodology
- Writing – Original Draft Preparation
- Writing – Review & Editing
- Supervision
Alex Costa Silva Federal University of Pernambuco https://orcid.org/0000-0002-5828-3598
- Investigation
- Methodology
- Writing – Review & Editing
Ramilla Vieira de Assunção Federal University of Pernambuco https://orcid.org/0009-0000-4011-3657
- Investigation
- Methodology
- Writing – Review & Editing
Gabriel D'annunzio Gomes Junior Federal University of Pernambuco https://orcid.org/0000-0001-8969-3605
- Investigation
- Methodology
- Writing – Review & Editing
Marcus Silva Federal University of Pernambuco https://orcid.org/0000-0001-9749-6644
- Investigation
- Methodology
- Writing – Review & Editing
Aouf Lotfi Centre National de Recherches Météorologiques https://orcid.org/0000-0002-0279-6773
- Methodology
- Investigation
- Writing – Review & Editing
Angelo Lemos Federal University of Southern Bahia https://orcid.org/0000-0003-1229-9807
- Investigation
- Methodology
- Writing – Review & Editing
Fabrice Hernandez University of Toulouse https://orcid.org/0000-0003-2152-0657
- Writing – Review & Editing

DOI:

https://doi.org/10.1590/2675-2824074.25257

Keywords:

SWOT, Altimetry, Significant wave height, Remote sensing

Abstract

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.