River Damming Threats by Climate-Driven Glacier Detachments

Yarlung Tsangpo on the Tibetan Plateau is the highest large river in the world. Valley glaciers in the Yarlung Tsangpo Grand Canyon pose high risk to the infrastructure in the region. In particular, the Zelunglung glaciers at the entrance of the canyon are experiencing rapid movements in the warming climate. This study presents a comprehensive assessment of glacier detachment risks based on remote sensing and physically based numerical analysis. Long-term meteorological records and debris-ice rheological modeling are used to reveal the volume and thickness of the instable source mass. An erosion–deposition debris flow analysis simulation program is employed to analyze multi-scenario hazard dynamic processes to predict the run-out distance, velocity, and deposition distributions. The deposition distributions along the river course in different glacier detachment scenarios are quantified to assess the size of possible barrier dam, which lays a good foundation for a quantitative risk assessment.