Assessment of SWOT-derived wind speed and significant wave height observations in typical and cyclonic conditions

This study evaluates the performance of the Surface Water and Ocean Topography (SWOT) mission’s Level-2 (L-2) products in retrieving sea surface wind speed and significant wave height (SWH), with a specific focus on tropical cyclone (TC) conditions in the Atlantic Ocean. SWOT-derived retrievals are collocated with in situ buoy observations from the National Data Buoy Center (NDBC). Accuracy assessment of wind speed reveals a root mean squared error (RMSE) of 1.71 m/s, a correlation coefficient (COR) of 0.84 and a scatter index (SI) of 0.30. Corresponding SWH metrics demonstrate an RMSE of 0.45 m, a COR of 0.91 and an SI of 0.28. Furthermore, wave hindcasting is performed utilizing the coupled Weather Research and Forecasting (WRF) model and WAVEWATCH-III (WW3) at 0.05° spatial resolution for 7 TCs possessing available along-track SWOT observations. Statistical analysis of SWOT data collocated with hindcasting results indicates an RMSE of 0.76 m for SWH up to 8 m, accompanied by a COR of 0.83 and an SI of 0.39. TC wave characteristics derived from SWOT observations demonstrate strong agreement with WW3 model outputs for SWH values reaching 10 m. With their high precision and unprecedented spatial coverage, these SWOT-derived wind speed and SWH products offer a valuable new resource for advancing oceanographic research.