Improved Process Management of Glacial Lake Outburst Flood Hazards by Integrating Modular Monitoring, Assessment, and Simulation

摘要

Southwestern Tibet is one of the areas seriously affected by glacial lake outburst floods (GLOFs). In this study, a systematic GLOF hazard management process chain for moraine-dammed lakes was constructed by integrating remote sensing (RS), geomorphology investigations, geographic information systems (GIS), statistical methods, and hydrological models. The evolution of two moraine-dammed lakes and their mother glaciers across the region from 1976 to 2018 were investigated and the susceptibility of 74 moraine-dammed lakes outburst was evaluated. The actual and potential GLOF risks of former Cirenmaco Lake GLOF was modeled based on a single hydrological model. The monitoring results showed that two moraine-dammed lakes in southwestern Tibet, including Yanongco and Rongxiazangbu, were continuing to expand and were at risk of GLOF. The parameters used for assessing GLOF risk were filtered through a grey correlation model with a modeling accuracy of 84. The FLO-2D hydrological model was adopted to simulate GLOF hazards of a moraine-dammed lake in Southwest Tibet for the first time. Results showed that the modeled errors of fluid depth and velocity were within 10. The combined method proposed in this study could be potentially used to assess the status of the regional GLOF in Tibet and provides effective suggestions for local governments to prevent disasters and reduce damages of GLOF.