Research Projects

High Mountain Asia (HMA), home to the third largest concentration of glaciers on Earth, is one of the most prominent areas of glacial retreat. The region also experiences natural disasters such as glacial lake outburst floods, catastrophic landslides, ice-rock avalanches, and debris flows (see, e.g., Chamoli disaster, Uttarakhand, 2021). The frequency and magnitude of these events have recently increased, owing to climate-warming-induced environmental changes. Although glacial mass loss and the rate of increase in landslides and flood activity in HMA are widely reported, the dynamics and long-term impacts of these earth surface processes on fluvial systems are poorly understood. This work therefore aims to present a comprehensive understanding on the linkage between glacier-fluvial interactions, and sediment budget in the HMA by employing remote sensing and ground-based approaches integrated with machine learning and artificial intelligence. To achieve our aim, the following specific objectives are set: (i) assess fluvial morphological changes such as migration in the drainage divide, knickpoint development, and river width dynamics in the headwater regions of Himalayan catchments caused by glacial retreat and landslides, (ii) quantify the sediment production and evacuation from the headwater catchment, and (iii) estimate the fluvial erosion and sediment discharge in future scenarios. Objective (i) can be achieved by using high-resolution topographic mapping based on UAV photogrammetric surveys, InSAR based deformation analysis and optical image offset tracking of the valley topography, which provide new insights into channel-erosion dynamics and mechanics to mobilize huge amount of sediments that accelerate channel erosion; objective (ii) can be achieved by monitoring the sediment export from the catchments using suspended sediment concentration measurements and sediment core sampling from reservoirs; and objective (iii) can be achieved by simulating the future glacial retreat and discharge scenarios using global climatic models, and then perform numerical simulations to estimate fluvial erosion. Concrete understanding of glacier retreat-induced fluvial geomorphic changes in HMA will maximize synergies among hazard mitigation and climate change adaptation efforts while improving early warning models.