The assessment also projects a three-fold increase in GLOF risk by the end of the century, with peak risk expected by 2050. The Hindu Kush Himalaya region, which boasts over 25,000 glacial lakes, contains 47 potentially dangerous glacial lakes.
A catastrophic glacial lake outburst flood (GLOF) struck the village of Thame in Nepal’s Khumbu region on August 16, 2024, causing extensive damage and loss of property. According to initial reports, 14 structures were destroyed, including a school, a health post, five hotels, and seven homes.
Thame, a key settlement in the Namche region of Solukhumbu, is known for its connection to Everest mountaineering, being home to prominent figures like Kami Rita Sherpa, a record-holding climber. The village lies downstream from several glacial lakes, which have shown considerable changes in size over recent years.
Satellite images from 2017, provided by the International Centre for Integrated Mountain Development (ICIMOD) and sourced from the European Space Agency’s Copernicus Earth Observation Programme, reveal that these lakes frequently expand and contract. ICIMOD researchers have noted that this variability makes the lakes highly susceptible to breaches, which can lead to dangerous outburst floods.
The region surrounding Thame, including the popular Tashi Lapcha Pass, contains several potentially hazardous glacial lakes. One such lake, Tsho Rolpa, is identified as particularly dangerous. ICIMOD scientists are conducting further investigations into the causes and impacts of the GLOF, utilizing both pre- and post-event satellite imagery. Their efforts aim to support national and local agencies, including Nepal’s Department of Hydrology and Meteorology.
ICIMOD’s 2023 assessment, titled “Water, Ice, Society, and Ecosystems in the Hindu Kush Himalaya,” highlights the unprecedented and largely irreversible changes occurring in the glaciers, snow, and permafrost of the region. The report warns that these changes are primarily driven by climate change, making the region one of the most vulnerable to such impacts globally. With 260 million people living in the Hindu Kush Himalayas, the accelerated melting of glaciers, shifting snowfall patterns, and increasing incidences of cryosphere-related hazards are severely affecting their lives and livelihoods.
Three-fold increase in GLOF risk
The assessment also projects a three-fold increase in GLOF risk by the end of the century, with peak risk expected by 2050. The Hindu Kush Himalaya region, which boasts over 25,000 glacial lakes, contains 47 potentially dangerous glacial lakes (PDGLs) within the Koshi, Gandaki, and Karnali river basins across Nepal, China’s Tibet Autonomous Region, and India. This area, known as High Mountain Asia, is a global hotspot for GLOF risk, with approximately one million people living within 10 kilometres of these lakes.
Tenzing Chogyal Sherpa, an ICIMOD Cryosphere Analyst and founder of the #SaveOurSnow campaign, expressed his anguish: “This flood has devastated a village I know well, affecting friends, neighbours, and relatives with deep ancestral ties. It is a stark reminder of the devastating impacts of climate change on mountain communities. Despite contributing minimally to greenhouse gas emissions, these communities face increasingly severe impacts.”
Dr. Nima Sherpa, a media and mountaineering outfitter from Khumbu and supporter of #SaveOurSnow, emphasized the urgency of global action: “The destruction in Thame underscores the severe and often catastrophic effects of climate change on mountain communities. It’s crucial for world leaders to act decisively to mitigate these impacts and support affected regions.”
Miriam Jackson, ICIMOD’s Cryosphere Lead, encapsulated the urgency of the situation: “Climate change is a crime scene, and the glaciers are making it visible. We cannot afford to look away.”