Work

On the use of SWOT altimetry data for monitoring coastal hydrodynamics

Year: 2025

Type: article

Abstract: Nowadays, most of satellite altimeters has proven to provide an effective dataset of sea surface changes in oceans and continental-shelf toward nearshore zones. The need to extend the satellite use to sea level and wave monitoring closest to the coast has introduced in several works to investigate the accuracy of observations at shallow water areas and coastal zones. This work has been conducted in the framework of the Surface Water and Ocean Topography (SWOT) wide-swath interferometric altimetry mission. Here, we provide insights into SWOT’s ability to monitor the nearshore and coastal Sea Surface Heights (SSH) and Significant Wave Height (SWH) in the English Channel, along the United Kingdom and French coasts with a special focus on high energetic periods, including storms. SWOT observations, including the 1-day Cal/Val and Scientific Orbit data, have been used to assess their performance, compared to in-situ measurements. This finding has exhibited good agreements between SWOT altimetry and in-situ measurements for both SSH and SWH with a maximum STD of 85 cm. A benchmarking analysis of SWOT observations for assessing coastal waves has shown significant results within a ~3-4 km radius and ~ 8-12 m depth from the coastline. This work presents the first investigation of the SWOT contribution for monitoring coastal hydrodynamics at shallow water areas. This challenging issue will benefit from SWOT ongoing works to offer reliable estimates of coastal hydrodynamics, which is crucial for improving numerical models at both regional and local scales.

Source: International Journal of Applied Earth Observation and Geoinformation

DOI: 10.1016/j.jag.2025.104982