Abstract ID: 3.11135 | Accepted as Talk | Talk/Oral | TBA | TBA

Glacial Lake Outburst Floods (GLOFs) are significant natural hazards, posing substantial threats to mountain communities worldwide. Early Warning Systems (EWS) are essential in reducing loss of life during GLOF events. However, efficacy of EWS is contingent upon factors including how warnings are disseminated and how communities respond. Despite the crucial role of EWS, there remain a paucity of study examining community experiences with GLOF early warnings, imperative for improving existing systems and making them more efficient. This study presents for the first time comprehensive documentation of public warning issuance, dissemination, and evacuation during the June 2019 Thorthormi GLOF event in Lunana, Bhutan. Through a household survey covering 102 at-risk households (over 70% of the affected population), we gathered detailed data on community perceptions of the warnings, the channels and sources of information, subsequent warning messages, evacuation processes, and actions taken by the at-risk people before evacuation as well as their future preparedness. Our preliminary analysis featured natural indicators such as unusually loud sounds from the river and ground vibrations served as the main source and channel of first warnings during the GLOF event. Additionally, mobile phone calls emerged as a common channel for disseminating both initial and subsequent warning messages. Notably, 37% of respondents reported helping others in evacuating, 29% told others to evacuate, and 24% packed their belongings before evacuating themselves. Although government’s outreach program has achieved instilling high-risk awareness, preparedness among the at-risk people was inadequate: evacuation to higher ground was the sole widely recognized action, with many uncertain about additional protective measures. Alarmingly, some individuals risked verifying floods by physically inspecting rivers before evacuating. Our study demonstrates the importance of integrating the firsthand knowledge and lived experiences of downstream communities affected by natural hazards (an element frequently overlooked in current approaches) into efforts to enhance scientific and institutional understanding of GLOF risks.