[19-May-2026] Feng, D., and Devkota, P. River widths and water surface elevation (WSE) measured by satellites (e.g., Landsat and SWOT) provide essential information for river discharge estimation. We developed a physics-based modeling-data assimilation framework to assimilate satellite–derived discharge into hydrological model simulations, which significantly improved the accuracy of the discharge estimates. We also developed a deep learning framework to directly integrate SWOT WSE data for discharge estimation. The results show that SWOT WSE observations can help improve discharge estimation for the Arctic rivers. Through the integration of satellite data with physics-based or data-driven models, we can produce continuous (every day, every river reach) discharge estimates for pan-Arctic rivers with improved accuracy. This product provides essential data for tracking freshwater discharge from rivers to the oceans.