University of Liverpool, UK
Dr Richard Boothroyd is a Lecturer in Physical Geography at the University of Liverpool. He works at the interface of remote sensing, fluvial geomorphology, and river-related hazards. His research advances an integrated programme on digital riverscapes, combining Earth observation, big geospatial data, and numerical modelling to understand river dynamics across spatial and temporal scales.
Systematic appraisal of geomorphic river mobility across the Ganga basin
Multi-decade satellite data are frequently used to assess changes in the wetted extents of large rivers, yet few studies investigate changes across their entire active width. Here, we analyse 15 major rivers in the Ganga basin to quantify geomorphic river mobility across active river channels, defined as the wetted channel and unvegetated alluvial deposits. Using Google Earth Engine, we derive biennial active channel masks from Landsat imagery (1990-2025) and calculate locational probabilities at kilometre intervals along each river.
At the system scale, results reveal differences in mobility between Himalayan and cratonic rivers. At the reach scale, many rivers exhibit spatially non-uniform mobility, with marked variation between reaches. We quantify this variability using cumulative frequency distributions and the Wasserstein distance metric, enabling the identification of reaches where changes are most pronounced.
To explore controls on mobility, observations are aggregated over 10 km reaches and were related to variations in active channel width and confinement. Planform metrics (e.g., braiding index, entropic braiding index, and sinuosity) provide additional geomorphic context. With increasing anthropogenic pressures in the Ganga basin (e.g., climate change, flow regulation, structural interventions), this approach can support river management activities.
