Glacial lake outburst floods (GLOFs) are a substantial hazard for downstream communities in vulnerable regions, yet unpredictable triggers and remote source locations make GLOF dynamics difficult to measure and quantify. Here, we revisit a destructive GLOF that occurred in Bhutan in 1994 and apply cross-correlation–based seismic analyses to track the evolution of the GLOF remotely (~100 kilometers from the source region). We use the seismic observations along with eyewitness reports and a downstream gauge station to constrain a numerical flood model and then assess geomorphic change and current state of the unstable lakes via satellite imagery. Coherent seismic energy is evident from 1 to 5 hertz beginning approximately 5 hours before the flood impacted Punakha village, which originated at the source lake and advanced down the valley during the GLOF duration. Our analysis highlights potential benefits of using real-time seismic monitoring to improve early warning systems.

冰川湖爆发洪水（GLOF）对脆弱地区的下游社区构成了重大危害，但不可预测的触发因素和偏远的源头位置使GLOF动态难以测量和量化。在这里，我们回顾了1994年在不丹发生的破坏性GLOF，并应用了基于互相关的地震分析来远程追踪GLOF的演变（距震源区约100公里）。我们使用地震观测以及目击者报告和下游测距站来约束数值洪水模型，然后通过卫星图像评估不稳定湖泊的地貌变化和当前状态。在洪水影响普那卡（Punakha）村庄大约5个小时前，从1赫兹到5赫兹明显出现了相干地震能量，它始于源湖，并在GLOF持续时间内向谷底发展。我们的分析突出显示了使用实时地震监测来改进预警系统的潜在好处。