Development of a GLOF forecasting system through a novel concept of pre-simulated library over the Hindu Kush Himalaya region

The Himalayan belt contains over 12,000 glaciers that have witnessed accelerated glacial melt due to concomitant climate change, leading to the formation of numerous unstable glacial lakes. These lakes, dammed by glacial deposits, pose significant mountain hazards due to their potential for sudden discharge of water and debris, causing devastating floods in the downstream reaches. To address the precipitous Glacial Lake Outburst Flood (GLOF) risks, there is a dire need to account for the impacts at near-real time, given their lesser warning times. The study proposes to develop a pre-simulated GLOF inundation library through a set of scenarios based on breach depths, breach widths, and moraine failure times to model extreme GLOF events over Safed Lake, a sensitive glacial lake in the Uttarakhand, India. At the first place, a geospatial analysis is carried out with a set of Landsat 9 images to ascertain the spatio-temporal dynamics. Using a set of scenarios within the 1D-2D coupled MIKE+ model, we perform flood inundation simulations to create a GLOF inundation library. This library will facilitate the selection of the closest inundation map based on near-real-time data; Thus, enhancing effective flood risk communication and preparedness. This innovative approach to GLOF modeling and flood risk communication is crucial for managing unstable glacial lakes with high flooding probabilities and short warning times. The findings underscore the importance of advanced modeling and timely communication in mitigating the impacts of glacial lake outburst floods and improving resilience in the Himalayan region.

 

Keywords: Climate change; Flood Risk Management; Glacial Lake Outburst Flood; Inundation library; Landsat 9; MIKE+;