Assessment of Ocean Swell Height Observations from Sentinel-1A/B Wave Mode against Buoy In Situ and Modeling Hindcasts

Synthetic Aperture Radar (SAR) in wave mode is a powerful tool for monitoring sea states terms of long-period ocean swells specific directional partition. Since 2016, SARs aboard Sentinel-1A/B operating have provided swell spectra dataset as Level-2 Ocean products on continuous and global basis over open oceans. Furthermore, Level-3 are processed by Copernicus Marine Environment Monitoring Services (CMEMS) taking the benefit unique “fireworks” analysis. In this paper, heights from during period June 2016 to 2020 evaluated. The reference data include collocated situ measurements buoys WaveWatch III (WW3) hindcasts. Assessment results show systematic overestimation approximately 0.2 m partitioned compared buoy observations eastern Pacific western Atlantic. Based reliable SAR-WW3 collocations after quality-controls, empirical corrections been proposed Sentinel-1 heights. Independent comparisons against WW3 hindcasts demonstrate validity our postprocessing correction both eliminating biases reducing root mean square errors. consistency between CMEMS also examined discussed case studies.