Deriving intertidal topography from SWOT data and Sentinel-2 data

Journal article, 2025

The Surface Water and Ocean Topography (SWOT) mission,initially designed to observe oceans and inland waters, proves valuable for mapping intertidal flat topography. This study presents a fusion method that integrates freely available SWOT interferometric altimetry data with Sentinel‐2 imagery. The density‐based spatial clustering of applications with noise algorithm is employed to accurately identify observation data located in the intertidal zone. Intertida ltopography with a 10m resolution were generated from L2_HR_PIXC data collected during SWOT's science phase (July2023–October2024) in the intertidal region along the coast of Jiangsu Province, China. These Digital Elevation Models were compared with laseraltimetry observations from
the ICESat‐2. SWOT observations show high accuracy, with RMSEs of 0.24m (multi‐cycle) and0.41m (single‐cycle), confirming their potential for intertidal monitoring. This study presents adata processing strategy that does not rely on ground‐base d observations, demonstrating potential for application in abroader range of regions.