Introduction
Climate change is significantly disturbing the Himalayan ecosystem, and environmental factors such as an increase in temperature in high mountains, reduced snowfall, and extreme weather events are at the forefront of the issue. High mountain villages and the accessibility and mobility of people unique to the Hindu Kush Himalaya (HKH) region must be considered when examining the vulnerability of Nepal to climate change (Dhimal et al., 2021). Glaciers are melting at alarming rates and accelerating from the development of glacial lakes, along with glacial lake outburst floods (GLOFs) being an immediate, increasing threat. It is certain that river flow rate will increase and then decrease as glaciers melt, jeopardizing water, food and energy security of Nepal and other countries that depend on glacial melt fed rivers. Diseases will expand into these areas as extreme weather events and temperatures increase. Ultimately, the general health and function of communities and ecosystems in Nepal will be significantly affected by the melting of glaciers in the Himalaya.
Glacial Melting
The melting of Himalayan glaciers has happened slowly but continuously, and glacier mass loss has been documented over at least the last five decades. Using 1975 ice mass levels as a baseline, about 87% remained in 2000 and 72% remained in 2016, showing an acceleration of mass loss (Maurer et al., 2019) The HKH is warming at a higher rate than the global average, along with precipitation significantly increasing over the last six decades (Dhimal et al., 2021). Many glaciers in the HKH are thinning vertically at a rate of 0.3-1 m/year, faster than the world average and threatening the health of the entire region. (Talukder et al., 2021). The average rate of ice loss is twice as rapid in the 21st Century compared to the end of the 20th Century, and trends show melt rates increasing each year through the 21st Century and beyond (Maurer et al., 2019).
The HKH hosts approximately 95,000 glaciers and holds the largest ice volume outside of the polar regions, and the topography and remoteness of the region makes expeditions and research difficult (Nie et al., 2021). The trending warming and melting rates in the region being faster than the rest of the world’s mountain glaciers shows how heightened concern is necessary (Nie et al., 2021). Small and low elevation glaciers have been found to be shrinking the fastest, and continuous mass loss has occurred and been documented over the last five decades (Azam et al., 2018). Most of the glaciers in the region exist between 5,000 and 7,000 meters, and these are the most at risk because warming temperatures could change precipitation patters from snow to rain (Prakash, 2020). A lot of snow exists year-round at these elevations, and rain would both decrease accumulation of snow and the albedo of the area. In a 1.5º C warming scenario, it is projected that these low elevation small glaciers are likely to lose approximately 50% of their mass by 2100, and the runoff is projected to decrease by 10% by the end of the 21st Century (ICPP, 2022).
BBC News. (2022, June 17). Nepal to Move Everest Base Camp Away From Melting Glacier- BBC News [Video]. Youtube. https://www.youtube.com/watch?v=1ESHqBVd8XM
Maurer, J. M., Schaefer, J. M., Rupper, S., & Corley, A. (2019). Acceleration of ice loss across the Himalayas over the past 40 years. Science Advances, 5(6), eaav7266. From https://doi.org/10.1126/sciadv.aav7266
Hazards Associated With Glacial Melting
Water Security
The greatest threat to communities in High Mountain Asia that glacial melting is imposing is on water supplies. Hundreds of millions of people rely upon naturally occurring glacial meltwater as a buffer to water supplies in the dry season (Nie et al., 2021). The amount of surface water available in the pre-monsoon season will increase as glaciers and snowpack melts, but in the long-term future there will be eventual pre-monsoon water scarcity as the glaciers and snowpack disappear (Dhimal et al., 2021). The main source of groundwater recharge is from glaciers, combined with surface runoff from mountain snow (Prakash, 2020). These changing water regimes, coupled with high population growth, create even more stress on water supplies which are being seen in the drying up of some springs (Prakash, 2020). Nepalese people living in the HKH depend on springs to transfer water to the surface in the dry season, and in the long-term future regions will get less for irrigation and drinking (Talukder et al., 2021).
Food Security
The decline of springs from changes in the hydrological cycle due to climate change induced glacial melting has recently become a key source of concern given that a significant population in Nepal depend on them for daily water access for drinking and farming (Prakash, 2020). In a developing country where approximately 50% of the population is suffering from malnutrition, this lack of irrigation water will further impact the diets of millions of Nepalese people (Talukder et al., 2021). The food security for communities at higher altitudes is much more sensitive to glacial melting than ones at lower elevations. This is because their farming practices rely much more heavily on seasonal melting since precipitation decreases with altitude (Wood et al., 2020).
Energy Security
Nepal and other countries in the HMA have invested heavily in hydropower plants to support growing populations. The short-term increase in water availability might not be universally advantageous for hydropower plants, as predicted floods and droughts will negatively alter the efficiency of electricity generation (Nie et al., 2021). As glaciers deplete and stream flow decreases, the dams will produce disproportionately less power than the amount of water flow lost, as a 1% reduction in stream flow can reduce the output by 3% (Laghari, 2012). This means that in the long-term they will be not be able to generate enough electricity to stay in use, prompting an increase in fossil-fuel generated electricity
Emergence of Diseases and Human Health
Studies suggest that the increasing temperature and frequency of extreme rainfall events is now more conducive for the survival and reproduction of diseases, such as dengue virus, which is predicted to expend in Nepal and to higher elevation regions (Dhimal et al., 2021). Importantly, these diseases will disproportionately affect the poorest populations in the region (Talukder et al., 2021). Outbreaks of infectious diseases historically follow natural disasters that displace large populations of people and promote the transmission of diseases (Kouadio, 2012). Flooding is one such natural disaster that has the potential to displace entire communities, and is predicted to increase in frequency in the coming years. Human health is the greatest when all ecosystem services are working at full capacity because they make vital contributions to disease prevention and improved human wellbeing, however glacier depletion will affect how well these ecosystems work, and lead to increased stress, malnutrition, immune suppression, greater susceptibility to disease, and the emergence of new diseases (Talukder et al., 2021).
Scientific American. (2020, January 15). This is What a Glacial Lake Outburst Flood Looks Like [Video]. Youtube. https://www.youtube.com/watch?v=BDPbtP-0AW8
Glacial Lake Outburst Floods
The melting of glaciers and warming temperatures has expanded many proglacial, supraglacial, and subglacial lakes, with more than 5000 glacial lakes that are at risk to glacial lake outburst floods (GLOFs) (Talukder et al., 2021). The proglacial lake area expanded by more than 50% in the Himalaya between 1990 and 2015 (King et al., 2019). These ponds and lakes also impact glacial changes, as they absorb thermal energy from the sun and then transmit the energy back into glacier ice, causing even faster melting (Nie et al., 2021). The frequency and magnitude of GLOFs have increased in recent decades, as the warming climate of the region weakens the moraines and dams that hold these lakes back (Dhimal et al., 2018). A total of 65 glacial-lake outburst floods in the Himalaya since 1930 have been observed and recorded, with an increasing trend since 1950 being reported (Nie et al., 2021). In 2013 a sudden GLOF killed upwards of 6000 people, which raised concerns about flood risk management in the region (Fischer et al., 2022).
Exposure and Vulnerability
Climate change is impacting nearly all aspects of life for people living in Nepal. The expected trend of water insecurity in the long term future will heavily affect Nepalese communities because it is a developing country- ranking 143rd of 191 countries in the world on the Human Development Index (UNDP, 2022). It is known that the effects of water insecurity has a disproportionate impact on developing and low-income countries than on middle or high-income countries, and will also affect women, children, elderly and Indigenous peoples the most (ICPP, 2022). It is expected that women and children, who suffer more from malnutrition and access to water, will generally carry a higher health burden and have less power to adapt to the effects of climate change (Dhimal, 2021).
Nepal's adaptation measures are also vulnerable, as they have been plagued by the inequalities based on gender, caste, and class that are deeply embedded into Nepalese culture (Nightingale, 2018). The country's economy is agrarian based, and therefore is high sensitive to climate change due to its effect on natural resource availability like food and water (UNDP, 2010).
Nepal hosts more glacial lakes than any other Himalayan country, which poses serious threats to communities living downstream in the form of GLOFs. There is a growing need for glaciologists to monitor these lakes as they form, as there is not enough data currently to provide an accurate understanding to make decisions regarding adaptation (Nightingale, 2018). High mountain communities are very vulnerable to the threat of GLOFs due to this lack of data, and loss of life could be prevented with a greater understanding of this threat.
Adaptation and Resilience
More Research Needed
The number of studies on Himalayan glaciers is very limited, and even fewer have the quantitative aspect needed to better understand how their melting affects the planetary health of the region (Talukder, 2021). While of the quantitative research that is out there has very similar results, there are some data gaps that need to be filled. Wider reaching and longer timescale assessments of glacier masses, ecosystems dependent upon or surrounding glacial areas is needed (Xu, 2009). Weather stations, river flow gauges and glacier mass monitoring sites are needed to provide data to close any knowledge gaps and better inform planning current and future adaptation measures (Nie et al., 2021). Collaboration between different nations will be helpful when conducting further research as well, and will create better adaptation plans for the future (Talukder, 2021).
Current Adaptation Strategies
Adaptation planning in Nepal is focused on physical threats combined with social and economic indicators (Nightingale, 2018). Innovative climate change adaptation planning has been launched, with clarity on climate change threats given to local communities, and many promising adaptation options have been identified (Schumacher, 2020). These include water conservation measures, improved pasture management, and providing alternative income opportunities (Schumacher, 2020). Nepal engages in a multi-stakeholder process when deciding on adaptation plans, which is unusual globally but is normalized in the local culture as consensus decision is highly valued (Nightingale, 2018).
NAPA and LAPA
The Nepal National Adaptation Program of Action (NAPA) and the Nepal Local Adaptation Program of Action (LAPA) are two governmental organizations that are currently leading adaptation planning in Nepal. The focus of the two groups are to first identify the most vulnerable areas to climate change and then to promote activities that can increase the adaptive capacity and resilience of vulnerable areas (Nightingale, 2018). There is a national and local group because some of the climate change threats that Nepal is facing are very unique to different groups and communities, which is something that a strictly national plan cannot fully address (Nightingale, 2018). So far, the capacity of villages to plan the management of natural resources and make decisions has been strengthened through LAPA, and these measure will make the residents of high mountain regions better able to adapt to their changing climate (Schumacher, 2020).
Future Adaptation Strategies and Recommendations
Vulnerability needs to be integrated into the planning and managements of climate change adaptation, and measures need to be taken to prevent the risk of uncertainties, such as data gaps in glacial research being compounded and threats being magnified (Rasul, 2019).
Management of health systems. An action plan to address the health risks that will arise in the future from climate change in the region is necessary. These plans are an extremely useful tool, especially for women, children and Indigenous peoples who are hard to reach (Dimal, 2021). While the creation of such a plan is a daunting task, the implementation is possible and can empower those people who are most vulnerable to the effects of climate change.
Early warning systems for flooding. Before tragic GLOF events in 2012 and 2013, there was no warning of the impending flood. In the aftermath, public awareness and preparation was heightened and early-warning systems were implemented, but interviews with local residents showed that the systems lacked maintenance and were inoperable in the past years (Fischer et al., 2022). These early warning systems should be improved, implemented in more places, and maintained better in future years to prevent the loss of life from GLOFs.
World Wildlife Fund. (2013, May 30). Climate Change Adaptation (Langtang)[Video]. Youtube. https://www.youtube.com/watch?v=Yvk7bu65BQQ&t=2s
United Nations. (2018, January 17). Nepal: Adapting to Climate Change [Video]. Youtube. https://www.youtube.com/watch?v=f6ca99wJ9g4
About The Author
About the author
Nicholas Ware studied environmental-economics at St. Lawrence University and graduated in 2024. From a small town in Massachusetts, he is passionate and experienced in outdoor recreation, specifically skiing, hiking and climbing. He has always loved spending time in nature and his fervor for climate science arose from the changes he saw first-hand throughout his experiences in the outdoors. He hoped that his research on glacial melting in Nepal would educate people on a lesser-known impact of climate change and inspire them to be more engaged in the fight to stop the effects of climate change.
References
Nightingale, A. J. (2018). Nepal’s Towering Climate Adaptation Challenges. Current History, 117(798), 135–141. https://www.jstor.org/stable/48614341
Schumacher, P. (2020, July 2). The conservation standards-based method for planning and implementing ecosystem-based adaptation strategies. Panorama- Solutions for a Healthy Planet. Retrieved from https://panorama.solutions/en/solution/conservation-standards-based-method-planning-and-implementing-ecosystem-based-adaptation
Kouadio, I. K., Aljunid, S., Kamigaki, T., Hammad, K., & Oshitani, H. (2012, January 10). Infectious diseases following natural disasters: Prevention and control measures. U.S. National Library of Medicine. From https://pubmed.ncbi.nlm.nih.gov/22149618/
Talukder, B., Matthew, R., vanLoon, G. W., Bunch, M. J., Hipel, K. W., & Orbinski, J. (2021). Melting of Himalayan glaciers and planetary health. Current Opinion in Environmental Sustainability, 50, 98–108. From https://doi.org/10.1016/j.cosust.2021.02.002
Laghari, J. (2013). Climate change: Melting glaciers bring energy uncertainty. Nature, 502(7473), 617–618. From https://doi.org/10.1038/502617a
Wood, L., Neumann, K., Nicholson, K., Bird, B., Dowling, C., & Sharma, S. (2020, April 29). Melting Himalayan Glaciers Threaten Domestic Water Resources in the Mount Everest Region, Nepal (C. Song, Ed.) [Review of Melting Himalayan Glaciers Threaten Domestic Water Resources in the Mount Everest Region, Nepal]. Frontiers in Earth Science; Frontiers. From https://www.frontiersin.org/articles/10.3389/feart.2020.00128/full
Dhimal, M., Bhandari, D., Dhimal, M. L., Kafle, N., Pyakurel, P., Mahotra, N., Akhtar, S., Ismail, T., Dhiman, R. C., Groneberg, D. A., Shrestha, U. B., & Müller, R. (2021, June 30). Impact of climate change on health and well-being of people in Hindu Kush Himalayan region: A narrative review. Frontiers. From https://www.frontiersin.org/articles/10.3389/fphys.2021.651189/full
Prakash, A. (2020, September). Retreating Glaciers and Water Flows in the Himalayas: Implications for Governance [Review of Retreating Glaciers and Water Flows in the Himalayas: Implications for Governance]. ORF Online; ORF. From https://www.orfonline.org/wp-content/uploads/2020/09/ORF_IssueBrief_400_HimalayanGlaciers.pdf
Maurer, J. M., Schaefer, J. M., Rupper, S., & Corley, A. (2019). Acceleration of ice loss across the Himalayas over the past 40 years. Science Advances, 5(6), eaav7266. From https://doi.org/10.1126/sciadv.aav7266
Azam, M. F., Wagnon, P., Berthier, E., Vincent, C., Fujita, K., & Kargel, J. S. (2018, January 9). Review of the status and mass changes of Himalayan-karakoram glaciers: Journal of Glaciology. Cambridge Core. From https://www.cambridge.org/core/journals/journal-of-glaciology/article/review-of-the-status-and-mass-changes-of-himalayankarakoram-glaciers/BDF72DED08FC3BC6584CD4F745EB1595
King, O., Bhattacharya, A., Bhambri, R., & Bolch, T. (2019, December 2). Glacial Lakes exacerbate himalayan glacier mass loss. Nature News. From https://www.nature.com/articles/s41598-019-53733-x
Nie, Y., Pritchard, H. D., Liu, Q., Hennig, T., Wang, W., Wang, X., Liu, S., Nepal, S., Samyn, D., Hewitt, K., & Chen, X. (2021, February 2). Glacial change and hydrological implications in the Himalaya and Karakoram. Nature News. From https://www.nature.com/articles/s43017-020-00124-w
World Bank Group. (2022). Nepal - country climate and development report. International Finance Corporation. From https://www.ifc.org/wps/wcm/connect/publications_ext_content/ifc_external_publication_site/publications_listing_page/nepal-country-climate-and-development-report
IFCC, 2022: Technical Summary. In: Climate Change 2022: Impacts, Adaptation and Vulnerability. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 37–118, doi:10.1017/9781009325844.002
UNDP. (2022, September 12). Nepal moves up one place in human development, ranks 143rd: United Nations Development Programme. United Nations Development Program. Retrieved from https://www.undp.org/nepal/press-releases/nepal-moves-one-place-human-development-ranks-143rd
Schumacher, P. (2020, July 2). The conservation standards-based method for planning and implementing ecosystem-based adaptation strategies. Panorama- Solutions for a Healthy Planet. Retrieved from https://panorama.solutions/en/solution/conservation-standards-based-method-planning-and-implementing-ecosystem-based-adaptation
Rasul, G., & Molden, D. (2019, May 27). The Global Social and economic consequences of Mountain Cryospheric Change. Frontiers in Environmental Science. Retrieved from https://www.frontiersin.org/articles/10.3389/fenvs.2019.00091/full
Fischer, M., Brettin, J., Roessner, S., Walz, A., Fort, M., & Korup, O. (2022, September 26). Rare flood scenarios for a rapidly growing high-Mountain City: Pokhara, Nepal. Natural Hazards and Earth System Sciences. Retrieved from https://nhess.copernicus.org/articles/22/3105/2022/