Joint expedition to Yala Glacier, Langtang, Nepal


From 2 to 12 May, ICIMOD and Kathmandu University joined an expedition organized by the Institute for Tibetan Plateau Research, Chinese Academy of Sciences (ITP/CAS) and Tribhuvan University to take measurements on Yala Glacier in the Langtang Valley of Nepal. The measurements were taken as a part of the Cryosphere Monitoring Project (CMP), funded by the Norwegian Ministry for Foreign Affairs. Collaboration between the institutes is important because resources are shared for glacier research to understand the climate signals and processes on the glacier influencing the downstream water regime in the Hindu Kush Himalayan region. The goal of the expedition was to take glacier mass balance measurements and to survey Yala Glacier, as well as to maintain and download data from automatic weather stations. Additionally, there were other collaborating research teams in the Langtang Valley conducting measurements on debris-covered glaciers, which complement the conducted glacier measurements.

The expedition team reached Yala Glacier in a trip including a 1-day bus ride and several days of trekking. This is a long but necessary journey to acclimatize to the high altitudes between 5100 m and 5500 m a.s.l. on the glacier. During the expedition, there were generally early mornings with great weather and clear skies, with clouds building up in the late morning and variably overcast skies with rain in late afternoon, or hail and snow at high elevations. Therefore, the researchers got up early to make best use of the good weather in the mornings, when also the snow cover was hard and easy to walk on. The work went ahead well, despite thick snow cover at higher altitudes and on the glacier. The team read melt and snow accumulation from bamboo stakes that were installed in the glacier ice in the years before. At each stake location they also dug a snow pit to record the snow profile, measured the snow depth to the glacier ice and the snow density. Especially in the higher reaches of the glacier where the snow pack was very thick, they used an ice corer to retrieve snow cores up to 2.5 m deep. The researchers noted the depth where they found ice layers in the snow core and weighed the snow to derive the snow densities. 

Trekking back to Langtang Village, the clouds gave free view on the hanging glaciers above Singdum Village. Ice breaking off the hanging glaciers poses a threat to the village below, especially when big chunks of ice break off onto rock and creates a dust avalanche. The pressure wave preceding the ice particles of the dust avalanche have a very destructive force and have damaged several houses in Singdum Village and killed a young father and infant baby girl in the spring of 2011. Countless mani walls, chortens, and rocks with prayer flags line the track from Singdum to Mundu Village and are evidence for the piousness of the villagers, who have been living with natural and other hazards for a long time. The mani walls and chorten are roughly estimated to be up to 400-500 years old.

All photos by Dorothea Stumm

Expedition team in front of the Chinese Automatic Weather Station in Kyangjing, Langtang

Snow-covered Yala Glacier with the frozen proglacial lake in the foreground in May 2013

Drilling with the ice corer up to 2.5 m deep to measure snow accumulation

A wall with prayers in Singdum Village and hanging glaciers in the background