Climate change and Nepal

Climate scientists warn us that Nepal is likely to be one of the countries hardest-hit by climate change, despite being one of the smallest contributors to climate change (0.025% of the global share of GHGs). Climatologists are also clear that unless global greenhouse gas emissions are reduced significantly (to 350ppm) within a short period of time (2-10 years), our region will be unable to avoid the worst impacts of climate change. Worst impacts for this region include a) melting of much of the Himalayas by 2035 and the associated flooding, droughts, water shortages and rise in infectious-diseases, and b) changes in monsoon patterns and consistency and associated increase in extreme weather incidents and food shortages (due to changes in crop yields).

Nepal, unfortunately, is also likely to bear the consequences of global warming earlier than most other regions as temperatures have been found to be increasing more rapidly, on average, in Nepal than most other places the around the world. One study indicates that the average temperature in Nepal has been increasing at a rate of approximately 0.06 ºC per year (0.04 ºC per year in the Terai, and 0.08 ºC per year in the Himalayas) between the years 1977 and 1994. Another temperature analysis reveals that the average temperature in Nepal has increased by 1.8 ºC from 1976 to 2005. Both of these increases are far greater than the 0.74 ºC increase in average global surface temperature seen in the last 100 years.

Himalayan Meltdown

Climate change is causing a rapid meltdown of the Himalayas. The Himalayas, often referred to as the third pole of world, account for roughly 30% of global glaciers with 3,252 glaciers and 2,323 glacial lakes in Nepal alone. Snow and glaciers from the region provide vital fresh water supplies for all of Nepal and a sixth of humanity feeding seven of Asia’s major waterways, the Ganges, Indus, Brahmaputra, Salween, Mekong, Yangtze and Huang Ho. Climate change is, however, causing an unprecedented rate of melting; Himalayan glaciers in the Hindu-Kush region have been found to be retreating between 0.3 – 1 m per year while Nepalese glaciers are retreating from several meters to 20 meters per year.

The rapidly melting snow and glaciers pose catastrophic threats to the livelihoods of over 1.3 billion people living in the region, in the immediate future as well as in the long-run. Immediate risks include outbursts of glacial lakes wiping out villages and infrastructure damage in downstream regions; Nepal has already seen at least five major glacial lake floods since 1970 and more than 40 glacial lakes are known to be on the verge of bursting. In the long-run, there is the threat of a dramatic reduction in Himalayan waters, posing an unparalleled water scarcity threat to millions across Asia depending on Himalayan-fed rivers.

Unreliable river water availability

The melting of the Himalayas and the expected changes in the consistency of the monsoon rain patterns will likely lead to increases in extreme fluctuations in river water levels which will compromise water availability for general use and power generation. For instance, a Department of Hydrology and Meteorology study shows that flow levels in the Karnali River will increase by 13% with a 4 C temperature rise and a 20% precipitation increase. These fluctuations in water levels pose severe threats to drinking water supplies in urban and rural communities in Nepal that are heavily dependent on rivers and streams for water. Changes in monsoon patterns will also likely lead to inconsistent periods of intense precipitation and dry spells.

Reduced Electricity Generation Capacity

The hydropower sector, which currently provides a majority of Nepal’s electricity will likely be hard hit. Extreme weather conditions and GLOFs will also make hydropower installations more vulnerable and less reliable as an energy source. Fluctuations in water levels, for example a possible dramatic reduction in water levels in the winter dry period, could pose significant uncertainties on power generation capacity. Changes in sediment load can also cause problems.

Health Impacts

Higher maximum temperatures and warmer days can lead to:

• An increase in vector borne diseases such as malaria
• Increased endemic mortality and serious illness in older age groups and urban poor
• Increased damage to a wide-range of crops
• Extended range and activity of some pests
• Increased heat stress in livestock and wildlife

Higher temperatures are a potential contributor to the increasing trend of Malaria, Kala-azar and Japanese Encephalitis cases in Nepal, particularly in warm and sub-tropical regions of the country.

Variability of monsoon

Rainfall data for the last 30 years in Nepal shows that while total annual rainfall has increased, overall consistency of the monsoon has reduced; rainfall is more concentrated and dry periods last longer. The changing monsoon threatens to dramatically impact the livelihoods of millions of Nepalis through:

• Decreased crop yields
• Increased flood, landslide, avalanche and mudslide damage
• Increased soil erosion
• Increased flood runoff
• Increasing recharge of some floodplains aquifers
• Increase in flood and drought magnitude and damages
• Increased summer drying and associated risk of drought
• Increased risk of forest fires

Social Impacts

The warming climate will also provide challenges in other areas as well:

• Rural women and urban poor will be under higher stress
• Poverty is likely to increase
• Large-scale international and local migration and conflicts