With rising temperatures, the water from melting glaciers collect at the lowest point of a mountain basin, forming glacial lakes. During periods of heavy rainfall, the amount of meltwater flowing into these glacial lakes causes water levels to rapidly rise.
Glacial lake outburst floods (GLOFs) occur due to a combination of factors including landslides, avalanches or increased rainfall threatening the structural integrity of the dam. This leads to the sudden release of water; endangering communities around the glacial lake as well as those living further downstream.
Doctoral student and lead researcher Sonam Rinzin said, “These communities can be struck by a GLOF with very limited warning or evacuation time. Because they are often located in remote and highly disconnected areas, they can also be more vulnerable after the event.”
...the team was able to model hypothetical GLOF scenarios to create a hazard map.
The research focused on Lunana, a remote village in Bhutan which neighbours Lake Thorthormi Tsho, the most dangerous glacial lake in the country. With the use of low-cost sensors to collect data on surrounding topography, the team was able to model hypothetical GLOF scenarios to create a hazard map. The development of these early warning systems provides a systematic basis for monitoring the risk of GLOFs.
The team is funded through the Natural Environment Research Council (NERC) while simultaneously working with the Royal Government of Bhutan (RGoB) and Druk Holding and Investments (DHI).
...integrating local knowledge is very important because it can provide an alternative source of information...
Rinzin also noted, “formal warning systems, which typically involve detecting a flood event and sending warnings to people at risk, may not always work as anticipated. Therefore, integrating local knowledge is very important because it can provide an alternative source of information during an event.”
The integration of local knowledge into these support systems has proven to be effective, with instances of residents taking to WeChat to warn those residing further downstream in areas previously affected in Bhutan. Community efforts such as using social media to warn residents reduces response time and facilitates evacuation.
The floods that devastated Nepal this August is proof of the sheer devastation GLOFs are capable of. With a death toll exceeding 1,000 and over 4,000 individuals unaccounted for, the impact on communities as well as their infrastructure has yet to be assessed. Rebuilding from the wreckage will prove to be a herculean task, as entire families have had their livelihoods wiped out by the floods.