In this week’s Video of the Week, former GlacierHub writer Sam Inglis shares footage from a traverse of the Gangja La––a 5,130 meter pass in Nepal––filmed in September 2019. The vantage point is from the High Camp, which according to Inglis was a debris-laden area, treacherous to walk on because of unstable rocks and snow cover, which was deeper than expected, concealing potential hazards.
In January, the International Centre for Integrated Mountain Development published the most comprehensive analysis to date of how climate change will affect the glaciers of the Hindu Kush Himalaya region. The high mountain area, known as roof of the world, is melting faster than anticipated, the report warned. Due to the remote location of many of the Himalaya’s 56,000 glaciers, however, ice collapse events are infrequently capture on camera.
Inglis, who is now a Nepal-based glacial hazards specialist, was part of a team trekking south out of the Langtang Valley. His video is a sobering glimpse of the third pole melting into a land of unstable lakes. “From the High Camp we could look straight into the supraglacial hollow and see the ice cliffs on either side of a glacial lake,” Inglis told GlacierHub. “It is clear that the lake has been burrowing its way down through the ice mass for some time.”
According to Inglis, the ice cliffs are no longer shielded by an insulating layer of debris. Exposure to direct sun and elements during the day is causing a continual shedding of debris into the lake.
A High Mountain Summit has issued a Call for Action in the face of rapid melting of the Earth’s frozen peaks and the consequences for food, water, and human security, as well as for ecosystems, the environment, and economies.
The three-day summit, convened by the World Meteorological Organization and a wide range of partners, identified priority actions to support more sustainable development, disaster risk reduction, and climate change adaptation both in high-mountain areas and downstream.
“The high mountain regions are the home of the cryosphere, and source of global freshwater that are transmitted by rivers to much of the world. Preservation of ecosystem function and services from these regions is essential to global water, food, and energy security,” says the Call for Action.
“Climate change and development are creating an unprecedented crisis in our high mountain earth system that threatens the sustainability of the planet. There is great urgency to take global action now to build capacity, invest in infrastructure, and make mountain and downstream communities safer and more sustainable. This action must be informed by science, local knowledge, and based on transdisciplinary approaches to integrated observations and predictions,” it says.
“We, the participants at the WMO High Mountain Summit 2019, hereby commit to the goal that people who live in mountains and downstream should have open access to hydrological, cryospheric, meteorological, and climate information services to help them adapt to and manage the threats imposed by escalating climate change,” says the Call to Action.
It commits itself to a new Integrated High Mountain Observation and Prediction Initiative as one of the tools to address the challenges of climate change, melting snow and ice, and water-related hazards and stress.
It urges that sustainable mountain development and mountain ecosystem conservation should be an integral part of international development policy, and that there should be strengthened transboundary cooperation in open data sharing, forecasting and prediction, policy development, and knowledge generation and sharing.
“It is very clear that the choices we make and urgent action we take now are critical for safeguarding our high mountain regions. This Summit has succeeded in connecting science, policy, and practice to define the roadmap for climate action,” said Mountain Research Initiative Executive Director Carolina Adler, who was co-chair of the summit. “We need to ensure that the science responds to people’s needs, supporting the information services they rely on to address risks.”
Water towers of the world
Mountain regions cover about a quarter of the Earth’s land surface and are home to around 1.1 billion people. They are known as the ‘water towers of the world’ because river basins with headwaters in the mountains supply freshwater to over half of humanity, including in the Hindu Kush Himalaya and Tibetan Plateau region, known as the Third Pole.
Presentations from around the globe highlighted that glacier and snow melt translates into a short-term increase in hazards like landslides and floods, and a long-term threat to the security of water supplies for billions of people.
Swiss Federal Councillor and Interior Minister Alain Berset described how Swiss glaciers have lost 10 percent of their volume in the past five years, including 2 percent in the last year. Five hundred smaller glaciers have disappeared, and by the end of the century, 90 percent of the remaining 4,000 glaciers may melt.
During the summer 2019 heatwaves, the equivalent of Switzerland’s
annual national drinking water consumption melted from its glaciers in
just 15 days, according to MeteoSwiss.
The summit declaration voices concern that “water security is becoming one of the greatest challenges of the world’s population, and that the uncertainties on the availability of freshwater from mountain rivers is a significant factor of risk for local and downstream ecosystems, agriculture, forestry, food production, fisheries, hydropower production, transportation, tourism, recreation, infrastructure, domestic water supply, and human health.”
Avoiding the impending crisis
The summit brought together more than 150 participants, representing
meteorology, hydrology, environmental and atmospheric sciences,
development agencies, research and academia, voluntary partnerships, and
The Call for Action is entitled: ‘Avoiding the Impending Crisis in Mountain Weather, Climate, Snow, Ice and Water: Pathways to a Sustainable Global Future.’
International observations show an acceleration in the retreat of 31 major glaciers in the past two decades. But lack of observations hinder reliable monitoring.
The summit noted “the scarcity of meteorological, hydrological, climate, and cryosphere observations in mountain regions, and the difficulties in accessing existing data.” But it also stressed the potential of space-based observing systems to improve the situation.
It also highlights the need for early warning and risk prediction systems that reach the people as well as decision makers in mountain areas so they are able to plan more resilient communities and take early action in the anticipation of hazardous weather, climate, and water events.
Integrated High Mountain Observation and Prediction Initiative
“WMO will provide leadership and guidance in the Integrated High Mountain Observation and Prediction Initiative. We need to improve observations, forecasts, and data exchange in mountain ranges and headwaters around the world. This is needed to address accelerating climate change, which has increasing impacts on vulnerable populations,” said WMO Deputy Secretary-General Elena Manaenkova.
WMO is working towards an integrated Earth System Forecasting and Prediction System, with strong engagement from the research community. To support this new integrated approach, WMO has reformed its constituent body structures. WMO’s newly formed Commission for Observation, Infrastructure, and Information Systems will be instrumental in the new Integrated High Mountain Observation and Prediction System Initiative, according to the commission president, Michel Jean.
The IPCC report said that current trends in cryosphere-related changes in high-mountain ecosystems are expected to continue and impacts to intensify. Snow cover, glaciers, and permafrost are projected to continue to decline in almost all regions throughout the 21st century.
This press release was republished from the Mountain Research Initiative. It first appeared on the WMO website,
Avalanches ripped across the landscape. Colorful prayer flags draped between rocks and blocks of ice stood out in bright contrast as they whipped in the wind. Icicles over five meters long dripped into white and blue streams that rushed along smooth, rippled, cavernous walls of ice. Meanwhile, streams of aspiring climbers—I among them—fought gravity and thin air to summit some of the world’s highest mountains.
I recently returned to the US after almost three months—March to June 2019—visiting a tiny portion of the “Third Pole” in the Himalayas of Nepal as part of a scientific research expedition in the Hinku, Gokyo, and Khumbu Valleys in Sagamartha and Makalu Barun National Parks. Part of the expedition focused on collecting high-altitude snow samples on the summits and glaciated flanks of Mera, Lobuche, and 8,516-meter (27,940-foot) Lhotse—the fourth highest mountain on the planet. Other research components of the expedition included botanical surveys in the lower valleys and interviewing locals about subjects as diverse as park management, changes in glaciers, and shifting politics in the region—utilizing Nepali students as translators.
My role on the expedition was primarily as social scientist with a research focus on perceptions of glacier recession, particularly comparing those of scientists with the lived experience and traditional beliefs of park residents. One question I had was how scientific literacy intersects with traditional beliefs and the future implications this may have for conservation and park management—an extension of prior long-term studies. I also investigated how expeditions and journey narratives can be used as tools in communicating climate change, as well as science and environmental issues more broadly.
My research trip happened to coincide with two separate National Geographic expeditions in the area—one attempting an ascent of Lhotse South Face and the other, Everest. In Kathmandu, I interviewed various individuals, including staff of the Nepal-based International Centre for Integrated Mountain Development (ICIMOD), who study, among many other things, Himalayan glaciers. At ICIMOD I spoke with a Nepali scientist who grew up in the Khumbu. Later in Kathmandu, I met a Sherpa owner of a trekking and climbing company, who also grew up in the Khumbu. Their dual perspectives as native residents of these areas and as scientists or business owners were extremely valuable. They provided specific details about the perceived risks of glacial lake outburst floods, long-term impacts of glacial loss on hydropower and drinking water, and how traditional conceptions of Sagamartha (Everest) and other mountains, lakes, and valleys as inhabited by gods, goddesses, and spirits might interact with scientific presentations of climate change and climate adaptation efforts.
In addition to my formal social science research aspirations, I participated in physical science data collection. Due to a variety of mishaps and illnesses, I was the sole member of the expedition to summit Mera and Lobuche, where I collected crucial snow samples, which, when processed, will reveal the quantity and origin of black carbon deposited on the glaciers. Black carbon accelerates the glacial mass loss already occurring due to climate change by reducing the albedo of glacier surfaces, thus absorbing more solar energy. My sample site on the summit of Mera tied the prior record for the highest elevation black carbon sampling site, which has been published in a formal paper (on the summit of Mera as it happens). This was soon broken however by samples collected on the summit push up Lhotse (though not yet published).
The expedition’s initial plans were to send two climbers to the summit of Everest and three to the summit of Lhotse. Once again, however, due to a variety of misfortunes, no Everest aspirants spent a night above Camp 2, leaving no one in position to attempt Everest. Only the expedition leader and I successfully summited Lhotse, as our third had to rescued by helicopter from Camp 2 due to bloody froth in his lungs—a clear symptom of high-altitude pulmonary edema. Our summit day began under a full moon and in the distance we watched a continuous line of headlamps crawling up Everest’s south summit.
Due to the slow process of acclimatization and some
weather delays, I was able to spend an exceptionally long time at Everest Base
Camp (EBC). Though it was a bit taxing, it gave me the unique opportunity to explore
sections of the Khumbu Glacier around EBC that are rarely seen by otherwise
occupied climbers and Nepali staff. I documented, through photography, short
videos, and writing, the quickly disappearing ice formations in this area. In
other words, I spent time with the glacier, getting to know and appreciate it
at multiple levels—developing a deep aesthetic appreciation.
I see my work here in part as a fledgling spinoff of photographer James Balog’s wonderful documentation of ice—the subject of the equally wonderful film Chasing Ice by Jeff Orlowski. I hope that my unique contributions include exploring little crevices that are missed by a wider view, creative writing, and an academic investigation into the scientific and indigenous cultural aspects of ice.
As I explored, I was struck by several recurring formations: countless and ever-transforming icicles, “mushrooms,” or small columns of ice capped by rocks; “snails,” which eerily resembled rock-shell-toting ice-creatures; intricately-textured and cracked spires, caves, and waves of ice; and the rare cluster of nieves penitentes—triangular blades of ice formed through sublimation. Each of these dwarfed by the great hanging and mountain glaciers surrounding EBC on all sides.
Avalanches—occasionally of awe-inspiring size and power—were numerous. One night at Camp 2, as I lay buried in my thick down sleeping bag, a nearby avalanche exploded downward at such volume that I was certain it would envelop me in the darkness. I resigned myself to my fate, which never came. Another avalanche roared outside my tent at Base Camp. I was later told by a National Geographic GIS specialist that it partially enveloped our camp in a cloud of snow. At least one client of our company was struck by the tail end of an avalanche, while a member of our expedition came within 10 meters of a different avalanche. It seems likely that the quantity and size of avalanches I witnessed was affected by climate change, part of a larger world-wide trend, well-documented in other regions.
I spent nearly a month and a half camping right on top of
a glacier. If not on a relatively thin layer of rock, as at EBC, then directly
on the ice. The glacier would often creak, pop, and groan, especially at night
as it expanded and contracted with changing temperatures. At Camp 2, I sometimes
felt deep vibrations ripple into my body. On one occasion, I heard a pop right
near my tent, followed by one after another moving off into the distance. By
the end, my tent at EBC hung precariously from its high platform of ice and
rock—undercut by melting and ready to fall.
I cherish the time I spent getting to know these glaciers
at multiple levels—as an object of scientific inquiry and source of data, a
nexus of traditional lifeways and beliefs, an aesthetic and sensual phenomenon,
and an ever-changing, perilous obstacle for summiting one of the highest
mountains on Earth. I hope that I will have future opportunities to come to
know other glaciers in all these ways.
See more photos and a forthcoming essay about this expedition here.
A recent video by NASA summarizes how the rapid melting of Asia’s high mountain glaciers, also know as Earth’s “Third Pole,” is affecting water availability. The video explains how NASA’s High Mountain Asia Team (HiMAT) aims to help in adaptation efforts by providing data and tools.
The video accompanies a feature article that highlights the project, which is described as “the most comprehensive survey ever made of snow, ice and water in these mountains and how they are changing.” Now in its third year, the team studies “three decades of data on this region in three broad areas: weather and climate; ice and snow; and downstream hazards and impacts.”
Due to the difficulties and dangers of visiting these high glaciated regions, “for most of human history, a detailed scientific study of these mountains was impossible,” according to the article. But “the satellite era has given us the first opportunity to observe and measure snow and ice cover safely in places where no human has ever set foot.”
The goals of the program include creating “an authoritative estimate of the water budget of this region and a set of products local policy makers can use in planning for a changing water supply,” called the Glacier and Snow Melt (GMELT) Toolbox.
NASA’s video explains the mission of HiMAT and provides contextual information on the receding of glaciers of the Third Pole.
It is well known that warming will deeply affect glaciers and ice at the poles. Many of the effects are observable today and will continue to impact wildlife, people, and their environments. Scientists are now beginning to better understand climate change in cold regions, such at the Andes and the Alps, outside the polar regions of the Arctic and Antarctica.
In a recent news article by Nature, researchers look at the climatological and glacial changes in the ‘third pole’, which encompasses the Himalayas, Hindu Kush, Karakoram and the Tibetan Plateau. They also consider the need for enhanced monitoring of the glaciers and water supply, to help scientist better understand the extent of glacier retreat now and in the future.
Third Pole Water in Sustaining Asian Societies
The third pole is one of the major freshwater resources in Asia. Meltwater from glaciers feed into some of the major rivers in Asia, including the Ganges, Yangtze, and Brahmaputra rivers. According to the article, these river basins provide critical freshwater resources to about one-fifth of the world’s population.
Water is inextricably linked to the rise of Asian societies, bestowing them with rich agricultural output and ensuring stability and longevity in a sometimes brutal climate region. “The struggle for water in modern history is a global story… But nowhere has the search for water shaped or sustained as much human life as in India and China” says Sunil Amrith in a feature by Quartz India.
A dependable, predictable supply of meltwater is the pillar upon which these societies rest. Climate change could topple that foundation. As groundwater and aquifers dry up in India, water resources from glaciers will become even more necessary. Analysts from NITI, a policy think tank in India, said to New Security Beat “Critical ground water resources that account for 40 percent of India’s water supply are being depleted at unsustainable rates”. Hydropower is a growing clean and renewable energy resource for many sectors across China, and irrigation plays a substantial role in crop production for rural communities. The loss of glaciers and rivers could mean dire economic impacts on these regions.
Projected Changes in Climate and Peak Water
Climate patterns over the third pole are now shifting. As temperatures rise and glaciers continue to melt, more glacial lakes will form and river will begin to dry out. The authors cited recent research which indicated that a projected weakening of the annual Indian monsoon will bring significantly less precipitation and snow over the Himalayas. As a result, the current mass-balance of glaciers in the region will be offset by more runoff than snow accumulation.
The change in mass-balance results in glacier retreat, occurring faster today than historic rates of decline. Eventually, many glaciers will reach their peak water output, with some as early as 2020. Peak water is the level at which glacier melt water output is at its maximum, and it’s considered to be the “tipping point” of water supply. Societies may benefit from the peak water with temporary outflow of more meltwater in rivers, yet the long-term effects will be detrimental.
Although peak water is short-lived, it will be particularly advantageous to some areas projected to experience less precipitation. However, once glaciers reach this level, they will continue to output less and less water. Other regions such as the Andes will also experience peak water, with many glaciers having already have met this max water output level. The loss of glaciers and rivers could be disastrous to dependent societies.
Room for Improvement: Monitoring Retreat and Risks
The authors also wrote about the hazards and risks associated with glacier retreat. Communities living in mountainous regions face with the risk of collapsing debris from glaciers. According to the piece, in October 2018, glacier debris and the resulting landslide dammed the Yarlung Tsangpo River. This led to flooding downstream, affecting regions as far as Bangladesh. According to an article by AGU100, a prompt evacuation prevented any lives from being lost.
Glacial avalanches pose a considerable threat to millions along Asia’s vast network of rivers and streams. According to researchers from the article, only 0.1 percent of glaciers and lakes in the region have monitoring stations, and few high-altitude areas have weather stations. There are plans to install over 20 new stations in the third pole area, which is a big improvement from the current 10 stations in the area. Proper training is necessary to properly operate weather monitoring technology and adequate collection of data.
The study also prioritized the importance of sharing this data with global and regional climate models, and making the needs of the local people central in climate change discussions. It is imperative that the changes in the third pole to be globally recognized, to better serve local communities and societies in safeguarding water security and cultivating sustainability.
From American Geophysical Union: “To this day, the ice volume stored in the many glaciers on Svalbard is not well known… This surprises because of the long research activity in this area. A large record of more than 1 million thickness measurements exists, making Svalbard an ideal study area for the application of a state‐of‐the‐art mapping approach for glacier ice thickness….we provide the first well‐informed estimate of the ice front thickness of all marine‐terminating glaciers that loose icebergs to the ocean.”
Read more about scientific advancements in measuring glacier thickness here.
Hydropower in Iceland: Opinions of Visitors and Operators
From Journal of Outdoor Recreation and Tourism: “The majority of visitors are against the development of hydropower in Skagafjarðardalir. They believe that the associated infrastructure would reduce the quality of their experience in the region that they value for perceived notions of it being untouched and undeveloped. If the quality of their experience is reduced, so would their satisfaction with that experience.”
Read more about the views regarding the impact of a proposed hydroelectric plant on the tourist experience in Skagafjarðardalir here.
8 Experts Explain What Mountain Communities Need Most
“What happens [in the Third Pole] can affect over 1.4 billion people and have regional and global ramifications.” – Tandong Yao
“Researchers and the media tend to focus on big glaciers, but it’s the much smaller and much less glamorous glaciers and ice fields that are going to affect mountain communities the most.” – Anil Kulkarni
Read more about future difficulties mountain communities will face, and how they should be addressed here.
A major conference highlighted significant evolution in research and international cooperation across the world’s so-called “Third Pole”. The Byrd Polar and Climate Research Center (BPCRC) hosted the “Third Pole Environment Workshop”, which featured 80 researchers from 15 countries, specialised in researching Earth’s “Third Pole”. It was the sixth event since 2009.
The Third Pole (TP) comprises 1.9 million square miles (5 million km2) — equivalent to over half of the continental United States — centered over the Tibetan Plateau. It extends from the Pamirs of Tajikistan, along the length of Hindu-Kush Himalayas, through to the Hengduan, Kunlun and Qilian mountain ranges of China.
The “Third Pole Environment (TPE) Workshop” — held at The Ohio State University on May 16-18 — was a rare opportunity bringing together specialists from around the world who “share an interest in the Third Pole region and wish to communicate their latest research results”, said the conference’s first circular.
GlacierHub caught up with Dr Paolo Gabrielli – a Principal Investigator and ice core specialist at Ohio State University’s BPCRC. He credited the TPE series’ success to the “longstanding collaboration and friendship between The Ohio State University’s Professor Lonnie Thompson, and the Institute of the Tibetan Plateau Research’s Professor Yao Tandong.” The American-Chinese duo began their pioneering work on China’s glaciers in the 1980s, before “the importance of studying glaciers and their connection to climate change” had been realised.
Asked about his impressions of the research being conducted at the TP, Dr Gabrielli remarked that “the study of the TPE region is still at the beginning.” However, “impressive monitoring programs” have been established, especially on the Tibetan Plateau. He believes that whilst it is “still too early to draw firm conclusions,” the data presently being gathered will bear significant fruits in years to come.
Understanding the TP is critical, as changes there have regional and global impacts. In addition to being the source region for rivers which sustain over 1.5 billion people across ten countries, the TP “significantly impact[s] climate systems in the northern hemisphere and even the whole globe,” remarked Professor Yao Tandong in his opening address. It is also home to thousands of glaciers which cover over 38,600 square miles (100,000 km2).
The cryosphere and hydrosphere are central components of the TPE workshops, however, experts who research the atmosphere, biosphere and anthroposphere (a ‘sphere’ of Earth specifically modified or made by human activity or habitats) were also represented. Professor Lonnie Thompson — a founding father of the TPE initiative — stated, “The Third Pole Environmental program is an international, multi-disciplinary collaboration among scientists, students, engineers, technicians, and educators.”
Building on this sentiment, Professor Thompson said, he “hoped that the TPE office will serve as a home base for collaborative research, as well as fulfil one of TPE’s most important missions: international collaboration through training of young scientists.” Dr Gabrielli revealed that students “were financially supported…[enabling them] to take part [in] this conference. ”
Asked what he thought the most pressing issues facing the TP are, Dr Gabrielli said, “The continuity of…freshwater (both in terms of quantity and quality) in the future is the main concern.” Whilst the research may well be in in its early phases, clear and troubling trends have already been revealed.
Temperature projections indicate that the region will be subject to a minimum increase of 1°C, and as high as 3.5-4°C in certain regions, by 2100. These could contribute to destabilisation of food or water, which could spell disaster for the people of the region. Research by Australia’s science agency CSIRO and the Scottish Crop Research Institute (SCRI) stated that the TP’s glaciers and snows supply 55% of Asia’s irrigation for cereal — 25% of what is produced globally — which feeds 2.5 billion people.
Bangladesh is a clear harbinger of the plight to come. It is heavily dependent on the TP, as the nation’s three major rivers — the Meghna, Ganges and Brahmaputra — originate in the Himalayas and Tibetan Plateau. In fact, 90% of Bangladesh’s water emanates from abroad, and controlled by fellow thirsty nations China and India.
A key barrier to many TP studies is the geopolitical and environmental hostility, compounded by the remoteness of areas under investigation. It can require days to weeks of travel to get to a study site, before the groundwork can even begin. Despite these significant challenges, attendees of this year’s conference called for the extension of their joint efforts, suggesting that their work expand to cover the “so-called Pan-Third Pole Region”. It was proposed to address the numerous and expansive voids in the data across remoter Asia.
Vigorous support that TPE programs have garnered is undoubtedly thanks to Professor Yao’s passion and commitment to uncovering the region. Yet China’s ambitious long-term targets may also be in play. The “One Belt, One Road”, a revival of Marco Polo’s ‘Silk Road’, will carve its way straight through the middle of the Third Pole. And China has been expanding its influence at the other two poles as well, by gaining observer status in the Arctic Council in 2013 and increasing its presence in Antarctica in recent years.
In conclusion, we asked Dr Gabrielli if there were any projects announced at the conference that were especially promising. He cited a new ice core in Guliya (Western Tibet) as a project of particular merit. Overseen by TPE’s Science Committee Chair Yao Tandong, “[it] may provide evidence of the oldest ice ever retrieved at low latitudes and thus an exceptionally long climate and environmental history of the TP,” remarked Gabrielli. Fellow paleoclimatologist and TPE Co-Chair Professor Lonnie Thompson said to China Daily that they hoped to “assess the regional characteristics of climatic and environmental variability over decadal to millennial time periods.” They were endeavouring “to determine how they compare with conditions elsewhere, including the Polar Regions.”
Last year, the team reportedly recovered over six tonnes of ice cores from the TP, as part of what Thompson called a “global salvage mission.”
Following the success of their sixth conference on the TPE – Professors Yao and Thompson are no doubt sharpening their ice-axes and strapping on crampons in preparation to recover rapidly disappearing ice from the world’s Third Pole.
Recent research has provided valuable information on glacier processes in the Hindu Kush Himalaya (HKH) mountains of South Asia, a region often called the “Third Pole” because it contains the largest area of ice outside the Arctic and Antarctic. Glacier retreat in this region has attracted considerable scientific and media attention. The 2007 Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) stated that Himalayan glaciers were shrinking faster than those in other parts of the world, and would likely be gone by the year 2035. This comment became controversial in 2009 because of its inaccuracy and weak basis in scientific research, and because glacier retreat in this region has major consequences for water supplies in one of the most densely-populated regions of the world. The IPCC made subsequent corrections in 2010.
This video from 2010, ‘Himalayan Glaciers Melting Faster Than Anywhere Else in World,’ conveys the tone of concern during the period of the controversy.
Stemming from this controversy, documenting the glacier coverage in the HKH has become a topic of critical importance. A recent study by Bajracharya et al. (2015) helps establish the extent of glacier coverage in the HKH region and the rate of glacier change in several basins in this region.
The rugged topography and the poor road networks in the HKH region have limited ground-based data collection. Remote sensing is therefore an attractive alternative. Bajracharya, a researcher at ICIMOD in Kathmandu, and his colleagues utilized satellite images, combining them in some cases with available ground-based data.
The study maps glacial coverage and retreat for a period extending from about 1980 (the precise date varies from location to location) through 2010. They map the decadal glacial change for the 1980s, 1990s and 2000s for four large representative basins which span the HKH region from west to east. The study basins are the Wakhan Corridor in Afghanistan, the Shyok Basin in Pakistan, the Imja Valley in Nepal, and the Lunana region in Bhutan. Glacier melt is a critical source of drinking and irrigation water for large populations in the regiona and critical to hydropower generation as well; glacial processes are also important because of the associated risks of glacier lake outburst floods (recap Imja Lake in Nepal).
So what can be learned from these newly assembled and analyzed data? First, the study reports, that despite the importance of glaciers in the HKH region, they cover only 1.4% of the region. In addition, it finds that glacier retreat is proceeding at different rates in different places. The most rapidly retreating glaciers are the ones located below 5000 m above sea level and the ones that are smallest in area. Combining these factors, the most impacted basin in the study is the Wakhan Corridor in Afghanistan.
The contributions of this study notwithstanding, scientific challenges in the HKH remain. The researchers note that there is continued uncertainty about glacier retreat and downstream impacts, because of uncertainties about future climate change and about the responses of glaciers to this change in this region, for which research remains incomplete. This study sets the stage for future research, looking to past data and suggesting directions of future work.
This prize-winning video from UNDP, the ‘Himalayan Meltdown,’ provides a thorough overview of the region and shows the need for ongoing research.