Monitoring the glaciers of the Himalayas

Geographical location:

Asia/Pacific > Southern Asia > Nepal

View of the Everest massif from the Singalila hills (Sikkim, India) from a distance of about 150 kilometers. From left to right: Mount Lhotse, Mount Everest and Mount Makalu, Nepal.


Known as the water towers of Asia, the Eastern Himalayas have the largest concentrations of glaciers outside the polar region. These feed seven of Asia’s great rivers, including the Ganga, Indus, Mekong and Yangtze, ensuring drinking water for millions of people.

But continued climate change is predicted to have a significant impact on the glaciers, leading to major changes in freshwater water flows. This will in turn affect biodiversity, people and their livelihoods. To better understand the potential environmental crisis, WWF is working in Nepal to document the threats posed by retreating glaciers Information will be used for communities to plan effective management and contingency plans.


Glaciers are highly sensitive to minor changes in the atmospheric temperature. They are therefore considered good indicators to help us to quantify changes in the Earth’s climate. It is widely accepted that climate change is the main factor behind the accelerated glacier retreat observed in the Himalayas.

The Eastern Himalayas has the largest concentrations of glaciers outside the polar region, with nearly 33,000 km2 of glacier coverage. This provides water amounting to 8.6 x 106m3 per year (Dyurgerov and Maier, 1997). The Himalayas are therefore deservedly known as the ‘Water Towers of Asia’. Recent research shows that Nepal Himalayas have 3,252 glaciers with a coverage of 5,323 km2 and an estimated ice reserved of 481 km3 (UNEP/ICIMOD, 2001).

Continued climate change is predicted to lead to major changes in freshwater water flows with dramatic impacts on biodiversity, people and their livelihoods. However, the relationship between climate change and glacial retreat, although confirmed by scientists at a general level, is not yet well enough understood to drive a detailed policy response.

The problems associated with glacier retreat in the face of climate change are not straightforward. On the one hand current increased melting induces a gradual increase in discharge. In the longer term, however, as glacial mass decreases there will be a ‘tipping point’ as runoff begins a decrease trend with massive implications. Perennial rivers could be changed into seasonal streams giving rise to freshwater scarcity in the summer months when melt waters contribute the bulk of the water (around 75%) to the Himalayan rivers.

The region’s agriculture and power generation are fully dependent on the freshwater supply fed by the discharges of the Himalayan glaciers. In the Ganga river only, the loss of glacier melt water would reduce July-September flows by two thirds, causing water shortage for 500 million people and 37% of India’s irrigated land.

Local people directly experience the impact of climate change and glacier melting through various hazards like landslides and floods. In Nepal, landslides and floods cause about 400 deaths annually (Khanal 1996 and destruction of important infrastructure worth USD 2.5 millions).

Several glacial lakes have been formed as a result of glacier retreat which could lead to catastrophic events like glacial lake outburst floods (GLOF) in valley’s downstream, resulting in destruction of valuable resources such as forests, farms, costly mountain infrastructures and even human life. In August 1985 a GLOF from the Dig Tsho (Langmoche) glacial lake destroyed 14 bridges and caused about USD 1.5 million damage to the nearby-completed Namche small hydropower plant. GLOF events bring significant changes in discharges in the perennial rivers originating from Himalayan glaciers and has severe implications on downstream freshwater regime.

The entire system of hydropower generation situated on these river systems will also be jeopardised. To avoid a major conflict over water in these regions, there is a need for proper management of water resources as well as proper understanding of the variability of water resources, particularly due to impacts of climate change and deglaciation process.

In order to manage the impacts of climate change on glaciers, the nature of these impacts with respect to individual glaciers or drainage basins need to be understood. In the Himalayas, although there has been research at a large scale on glacier retreat, there has been no work at the scale of the individual glacier or drainage basin.


- Contribute to the preservation of biodiversity and the livelihoods of local people, by improving their ability to cope with the consequences of glacial retreat in the Himalayas caused by climate change. Use evidence of climate change impacts on the Himalayas regionally and globally to spur decision makers and the general public to reduce greenhouse gas (GHGs) emissions.

- Document the threats posed by retreating glaciers to specific vulnerable community, ecosystem and economic sectors and begin the process of planning an appropriate community driven management response.

Specific objectives:

1. Validate existing scientific research on the relation between climate change, glacial retreat and changes in the freshwater regime in the region and develop a prediction model for glacial behaviour under different climatic scenarios.

2. Develop a freshwater vulnerability assessment for selected key sectors.

3. Develop a community driven management response for selected key sectors.

4. Communicate local climate impact stories through the WWF network to raise the sense of urgency on climate change in support of solution oriented work ( e.g. Powerswitch campaign).


The project will follow a 4-module approach:

- Module 1 will study the effect of climate change on 5 glaciers in the Nepal and Indian Himalayas through collection and collation of secondary data (at least for the past 20 years) and validation of those data through primary data collection by the project team on the representative glaciers identified through expert consultations. The result will be used to develop a model to predict the behaviour of these glaciers under future climate scenarios.

- Module 2 will develop a Freshwater Vulnerability Assessment (FVA). This will first examine (for the same 5 glaciers) the effect of glacier retreat on the downstream freshwater regime. It will then assess for the 3 larger glaciers, the implications of these changes for the people, economic sectors and biodiversity in the downstream areas. This will likely include issues such as consequences for canal irrigation systems, hydro-electric power generation systems, water quality and vulnerable species.

- Module 3 will develop and facilitate the implementation of a Community Driven Management Response (CDMR) for a particular community and economic sector or ecosystem. The strategy will be developed and implemented with the full participation of the relevant local stakeholders. It is expected that the continued implementation of the strategy will continue beyond the project lifetime as glacial retreat issues are integrated into local planning systems. This crucial issue of demonstrating how a community driven response can lead to climate impacts being integrated into existing planning frameworks and institutions will also have high potential for replication outside of the project.

- Module 4 will, in parallel with Modules 1-3, disseminate the findings among the key stakeholders at local, regional and national levels, local Institutions such as village committees, grassroot civil society organizations, scientific and research organizations, media (both at local, regional, national and where appropriate international), international community and donors, etc.

The objectives of the communication is threefold:

1. Sensitise national and local planners that climate impacts are major issues, the management of which can be integrated within existing planning frameworks and institutions.

2. Show general public and policy makers at a national level that climate change is real and having an impact today and that a national policy on climate issues is necessary.

3. Show international negotiators and international media that the emissions of industrialised countries are threatening species and livelihoods of hundreds of millions and need to be reduced.

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