Backwater Effects From River Ice Jams Observed With SWOT Pixel Cloud Data

Abstract This study examines the backwater effects from ice jams in Arctic rivers using the Surface Water and Ocean Topography (SWOT) satellite. Ice jams occur when chunks of ice accumulate and obstruct the river flow, causing rapid water level rises and flooding. The ice cover on the Klondike River (April 2024) and the Peace River (April 2023) is identified from optical images and compared with SWOT‐derived water surface elevations (WSE). Estimated water surface slope from high‐resolution river elevation profiles reveal notable backwater effects upstream of the ice jams; water surface slopes decrease markedly (Peace: from 80 to 10 cm/km and Klondike: from 300 to 150 cm/km). The Peace River profiles are compared with ICESat‐2 and Sentinel‐3 measurements, highlighting the advantages of SWOT's spatial and temporal resolution. SWOT's ability to resolve WSE profiles in rivers demonstrates its value for quantifying Arctic ice jams, improving both hydraulic process understanding and flood risk assessment.