A glacier monitoring journey to the Himalayas

Glaciers in the Himalayas have been melting faster than in other places in Asia. Last October, WSL doctoral candidate Achille Jouberton from the HIMAL group of Francesca Pellicciotti joined a scientific expedition to study the fast-melting Trakarding-Trambau Glaciers, close to the Everest region. In the WSL logbook, he relates his experiences in eastern Nepal.

From my personal diary: Day #16, 27 Oct 2023, Camp 4, 5600m a.s.l.Woke up at 2am with a headache, then again multiple times until 6:30am. Strong headache, felt like at Camp 1 a week ago. I prepared myself with difficulty and went for breakfast but could only eat half of it. Koji gave me pills for headaches and one for altitude sickness. At that time, I was almost sure I could not go with them to the glacier. Just when they were about to leave, I took the decision to try and go with them, and turn back if it’s too difficult after 30min, the time it takes for the medicine to kick-in. While a slight headache remained, I felt better soon and stayed with the team for the whole day, returning to Camp 4 at 3pm. [...] Tomorrow is the last major workday [...]. We should also be able to see Mount Everest! Weather forecast looks good, let’s hope I sleep reasonably well and wake up full of energy.

Auf meiner Expedition mit Koji Fujita und seinem Team von der Universität Nagoya bin ich auf fast 6000 m über dem Meeresspiegel (ü.d.M.) gestiegen, um die Gletscher Trakarding und Trambau im Osten Nepals zu untersuchen. Der japanische Professor besucht diese Forschungsstätte seit 2016 (mit einer COVID-Pause in den Jahren 2020 und 2021). Die Feldarbeit wäre ohne die Hilfe eines professionellen Trekkingunternehmens nahezu unmöglich. In diesem Jahr wurde unser wissenschaftliches Team von vier Sherpas und bis zu 27 Trägern begleitet. Wir brauchten sieben Tage, um vom letzten mit dem Bus erreichbaren Dorf (Gongar, 1276 m’ü.d.M.) bis zum Gletscherende (4600 m’ü.d.M.) zu wandern. Während der gesamten Expedition kümmerten sich die Sherpas um die Lagerlogistik, versorgten uns mit warmem Tee und Mahlzeiten und leisteten enorme Hilfe bei der Feldarbeit, der Routenfindung und der Sicherheit auf dem Gletscher.

Wir schliefen in sechs verschiedenen Lagern, die sich in zunehmender Höhe bis zu 5600 m’ü.d.M. befanden, wobei die nächtlichen Temperaturen auf -10/-15°C sanken. Die Aussicht von unserem Lager wurde immer atemberaubender, je höher wir kamen, und am Ende waren wir von Gletschern und über 6000 m’hohen Berggipfeln umgeben. Während wir nach und nach aufstiegen, waren Kopfschmerzen, unruhiger Schlaf und Kurzatmigkeit beim Wandern an der Tagesordnung. Ein weiterer Beweis, wie wichtig die unschätzbare Unterstützung durch einheimische Sherpas ist, die es gewohnt sind, in dieser Umgebung zu navigieren. Die Nächte fühlten sich sehr lang an, da wir zwischen 18:30 Uhr und 7 Uhr morgens in unseren Schlafsäcken lagen und sie regelmässig für unbequeme, aber notwendige Toilettenpausen verließen. Ich hätte auf jeden Fall mehr Bücher mitnehmen sollen, denn ich musste die Anzahl der Seiten, die ich mir jeden Tag erlaubte zu lesen, rationieren.

Our field sites, the Trakarding and Trambau glaciers, are flanked by two automatic weather stations (AWS) at 4850 and 5450m a.s.l. and dotted with more than 15 mass balance stakes covering most of the glacier’s elevation range. The highest of them is up at breath-taking 6000m a.s.l. It is very rare to have such observations from the upper areas of Himalayan glaciers. However, the relatively easy access to the accumulation area - the upper part of the glacier where more snow accumulates than is lost each year - of Trambau Glacier is why Prof. Fujita chose it as a research site. I say relatively for a reason: it does require a great amount of planning beforehand, and three weeks carrying hundreds of kilograms of equipment up the mountains. I was very impressed by the strength and friendliness of all the porters who accompanied us, without whom this expedition would not have been possible.

I am studying the Trambau-Trakkarding glaciers area to understand the past and future dynamics in snowfall accumulation and glacier mass changes. While for most of the work I sit in front of my computer, I still need to go out in the field to check whether my model outputs are reasonable. During this fieldwork, I installed a digital camera at the highest weather station, to gain information on snow depth and precipitation dynamics, two important variables not monitored previously. I can only hope that the camera will withstand the extremely low temperatures and still be working when we come back next year.

2023 was another bad year for glaciers in Europe, with little winter snowfall and high summer temperatures. At the Nepalese Trambau-Trakarding glaciers, unfortunately, the situation was similar. I have witnessed myself that even at the highest measurement stake at about 6000m a.s.l. the surface sank by 1 meter. That’s the second largest loss since the beginning of observations in 2016, after 2022. "It doesn’t really look like an accumulation area" told us Professor Fujita, where only a twenty centimeters thick layer of snow was covering the glacier ice.

Because of the complex influence of the Indian summer monsoon on the simultaneous glacier ablation and accumulation, the explanation for such high mass loss will require further analysis of the meteorological data we just collected. Unlike in the European Alps, most of the precipitation here falls during the warmer summer months, whereas winters are cold and dry and do not influence the glacier mass balance substantially.

Walking back down to the village, I thought to myself that although this had been a once-in-a-lifetime experience, I would still be glad to be back to civilization and its comforts. I was sure it would take months, if not years before I would feel the desire to go back to such a remote and cold place. In reality, though, I already felt I was ready to go back to the mountains before the end of the first week back in Kathmandu.