Estimation of river discharge and surface water storage from spaceborne data: full catchment coverage with optimal space and time resolution

• Applicants: Professor Dr.-Ing. Nico Sneeuw; Dr.-Ing. Mohammad javad Tourian
• Subject Area: Geodesy, Photogrammetry, Remote Sensing, Geoinformatics, Cartography
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 324641997

Insufficient observational evidence of hydrological parameters at the global scale is a major impediment for progress in hydrological modeling. As the data provision from in situ gauge networks is deteriorating, satellites come to the rescue. Although spaceborne sensors offer a synoptic and global view by their very nature, satellite products do have their own limitations in terms of accuracy, temporal resolution and spatial coverage. This project aims to greatly improve the observational database for two key hydrological variables, river discharge and surface water storage, by innovative modeling of results from satellite altimetry (water level) and satellite imagery (surface area) and also SWOT observations. To this end, existing densification methodology for high-resolution discharge estimation along rivers will be developed into a full-catchment approach. In the second phase, methods developed in the first phase will be further improved, not only methodologically, but also by using novel Sentinel and SWOT observations. The developed methods in the first phase rely on an implicit assumption of temporal stationarity of the time series involved. Therefore, phase 2 addresses non-stationarity of surface storage and discharge due to changes in geometry (sedimentation, erosion, etc.), to human interference (dams, levees, etc.) and to climate change.

• DFG Programme: Research Units
• Subproject of: FOR 2630: Understanding the global freshwater system by combining geodetic and remote sensing information with modelling using a calibration/data assimilation approach (GlobalCDA)