Multi-Source Satellite Altimeters for Monitoring the Footprints of Storm Waves in Coastal Areas

Nowadays, most satellite altimeters have proven effective in providing datasets on sea surface changes in oceans towards nearshore zones. The need to extend satellite sea level and wave records closer to the coast has been a focus of several studies investigating the accuracy of observations in shallow water areas and coastal zones, with the aim of monitoring spatial and temporal changes in the hydrodynamics. The recently launched Surface Water and Ocean Topography (SWOT), is the first wide-swath interferometric altimetry mission. Here, we integrate SWOT observations with 9 existing altimeters for assessing the Significant Wave Height (SWH) at regional and local scales with a special focus on high energetic periods. The monitoring of storms using multisource altimeters offer the possibility to enhance their evolution with full coverages. The combination of SWOT with conventional altimeters improves the time-sampling to capture the variability modes from inter-monthly to inter-daily scales, including storms; and the spatial sampling that would be expanded thanks to the SWOT 2D consistent view. The frequency analysis of SWH along tracks highlights the wavelength of wave features and their changes during storms. This challenging issue benefits from ongoing works of new altimeters, including SWOT, to offer reliable estimates of coastal waves.