Monitoring Surface Water Bodies in Taiwan by SWOT Lake And Pixel Cloud Products

In recent years, advancements in radar altimetry, particularly the Synthetic Aperture Radar (SAR) approach, have revealed fine-scale features over coastal ocean and inland waters. SWOT mission has offered unprecedented details and accuracy in observing the nuance of water surface gradient since its launch at the end of 2022. It provides a great opportunity to monitor the ungauged rivers and waterbodies timely and repeatedly. This study aims to utilize SWOT L2 Lake and Pixel Cloud products to monitor multiple lakes, ponds, and reservoirs in Taiwan. In our fieldwork consisting of 14 small ponds and 12 major reservoirs, it has been verified that the surface height and its temporal changes could be observed by SWOT at an accuracy of submeter level during cycles 3-26. After our reprocessing by clustering of pixel clouds within the predefined water masks, the accuracy can be further improved to <10 cm level. It is concluded that SWOT offers an alternative view of hydrological parameters, which can play a critical role in future water resources management.