Recent observations have brought into light retreat of snow cover atop Mount Everest. Researchers have noted a reduction of 150 metres in snow accumulation during the winter season of 2024-2025. This trend has been documented through NASA satellite imagery analysed from October 2023 to early January 2025. The findings indicate a concerning rise in the snow line, which reflects broader climate changes affecting the region.
About Snow Line and Its Implications
The ‘snow line’ is the elevation where snow remains throughout the year. A rising snow line indicates that snow is melting at lower altitudes. This phenomenon is a clear indicator of a warming climate. As temperatures increase, the boundaries of snow accumulation shift upwards. This trend has been observed consistently over recent winters, particularly in 2021, 2023, 2024, and 2025.
Factors Contributing to Snow Cover Loss
Several factors contribute to the loss of snow cover on Mount Everest. Warmer and drier winters have resulted in reduced snow accumulation. Notably, sublimation plays important role. Sublimation is the process where ice transitions directly to vapour, leading to mass loss in glaciers. Researchers have noted sublimation rates of up to 2.5 millimetres daily, exacerbating glacier retreat.
Impact of Drier Conditions in Nepal
The winter of 2024-2025 has been marked by exceptionally dry conditions in Nepal. Reports indicate that snow cover was only 20-25 per cent of normal levels. These dry conditions have led to extreme droughts in various provinces, particularly in Koshi Province. The persistent warmth and lack of precipitation have resulted in high snow lines, which have been consistently rising.
Recent Weather Patterns and Their Effects
January 2025 continued the trend of dry conditions, with above-average temperatures. This has allowed snow lines to remain elevated. As of January 28, 2025, the average snow line was recorded at 6,100 metres, a notable 150 metres higher than the previous December. The winter of 2023-2024 was characterised by limited snow cover, emphasising the ongoing changes in weather patterns affecting the region.
Long-Term Consequences of Climate Change
The ongoing changes in snow cover and rising snow lines on Mount Everest serve as a stark reminder of the impacts of climate change. The implications for local ecosystems, water resources, and global weather patterns could be deep. Continued monitoring and research are essential to understand the full extent of these changes.
Questions for UPSC:
- Discuss the implications of rising snow lines on global climate patterns.
- Critically examine the relationship between sublimation and glacier retreat in the context of climate change.
- What measures can be taken to mitigate the effects of climate change on high-altitude ecosystems? Explain.
- With suitable examples, discuss the socio-economic impacts of extreme drought conditions in mountainous regions.
Answer Hints:
1. Discuss the implications of rising snow lines on global climate patterns.
- Rising snow lines indicate a warming climate, leading to altered weather patterns globally.
- Changes in snow cover affect the albedo effect, which influences temperature regulation on Earth.
- Glacier retreat impacts freshwater availability, affecting ecosystems and human populations downstream.
- Increased evaporation rates can lead to more extreme weather events, such as heavy rainfall or droughts.
- Rising sea levels due to melting glaciers contribute to coastal erosion and habitat loss worldwide.
2. Critically examine the relationship between sublimation and glacier retreat in the context of climate change.
- Sublimation is the process where ice converts directly to vapor, contributing to glacier mass loss.
- Increased temperatures enhance sublimation rates, leading to accelerated glacier retreat.
- Researchers have recorded sublimation losses of up to 2.5 millimeters daily on Everest glaciers.
- Glacier retreat due to sublimation affects water supply for millions who depend on glacial meltwater.
- This process exemplifies how climate change directly impacts glacier dynamics and contributes to global sea level rise.
3. What measures can be taken to mitigate the effects of climate change on high-altitude ecosystems? Explain.
- Implementing sustainable land-use practices can help preserve high-altitude ecosystems.
- Restoration of degraded areas can enhance biodiversity and resilience to climate impacts.
- Monitoring and research initiatives can provide data to inform conservation strategies effectively.
- Community engagement and education can raise awareness about the importance of these ecosystems.
- Policies aimed at reducing greenhouse gas emissions are crucial for long-term climate stabilization.
4. With suitable examples, discuss the socio-economic impacts of extreme drought conditions in mountainous regions.
- Extreme droughts can lead to water shortages, affecting agriculture and food security in mountainous communities.
- Tourism, reliant on natural landscapes, can decline due to reduced snow cover, impacting local economies.
- Increased forest fires during dry conditions can destroy habitats and threaten livelihoods dependent on forestry.
- Droughts can exacerbate migration as communities seek more viable living conditions, leading to social strain.
- Health impacts, such as increased respiratory issues from dust and heat, can arise in drought-stricken areas.
