High Mountain Asia

Séminaires de Martin Hoetzle et Evan Miles, Lundi 28 Septembre 2020 de 14h30 à 16h00 en salle Lliboutry, Bât. Glaciologie

Special meeting "High Mountain Asia" on September 28 and 29, 2020, Lliboutry room

Nous recevrons ces 2 jours de fin septembre des collègues suisses et allemands avec qui nous collaborons. Ce sera l’occasion de plusieurs séminaires, auxquels vous êtes tous et toutes convié(e)s. Venez nombreux(ses) !

  • Lundi 28 septembre, à 14h30 : Martin Hoetzle (Department of Geosciences, Fribourg) nous parlera des glaciers d’Asie centrale, et Evan Miles (Swiss Federal Research Institute, Zurich), spécialiste des glaciers couverts de débris, nous présentera sa dernière étude sur les gradients de bilans de masse de tous les glaciers des hautes montagnes d’Asie.

We will welcome these 2 days at the end of September some Swiss and German colleagues with whom we collaborate. It will be the occasion of several seminars, to which you are all invited. Come and join us !

  • On Monday, September 28, at 2:30 pm : Martin Hoetzle (Department of Geosciences, Fribourg) will talk about Central Asian glaciers, and Evan Miles (Swiss Federal Research Institute, Zurich), a specialist in debris-covered glaciers, will present his latest study on the mass balance gradients of all the glaciers in the high mountains of Asia.

Séminaires du Lundi 28 septembre, de 14h30à 16h00 :

Re-establishment of cryospheric monitoring and capacity building in Central Asia

Martin Hoelzle1, Martina Barandun11, Tomas Saks1, Erlan Azisov2, Abror Gafurov3, Abdulhamid Kayumov4, Ruslan Kenzhebaev2, Marlene Kronenberg1, Horst Machguth1, Halim Mamirov5, Tamara Mathys1, Bolot Moldobekov2, Maxim Petrov5, Nadine Salzmann1, Ryskul Usubaliev2, Andrey Yakovlev6 & Michael Zemp7

1Department of Geosciences, University of Fribourg, Fribourg, Switzerland (martin.hoelzle unifr.ch)
2Central Asian Institute of Applied Geosciences, Bishkek, Kyrgyzstan
3GFZ German Research Center for Geosciences, Potsdam, Germany
4Center for Research of Glaciers of the Academy of Sciences Tajikistan, Dushanbe, Tajikistan
5Glacial Geology Laboratory, Tashkent, Uzbekistan
6Uzbek scientific investigation and design survey institute, UzGIP, Tashkent, Uzbekistan
7Departement of Geography, University of Zurich, Zürich, Switzerland

Climate change poses a major challenge for humanity and the related global implications will influence and threaten future economies and livelihood of coming generations, especially in developing countries. One region, where climate change has major impacts is Central Asia. With the Tien Shan and Pamir, the region contains two of the largest mountain systems of the world, which serve as water towers in arid and continental region. Future water resources in these regions depend strongly on the cryosphere, particularly on snow, glaciers and permafrost. These cryospheric components store enormous amounts of water in its solid form. These resources will play an important role for future water availability under the ongoing climate warming influencing future water resource management. Several recent studies point out clearly that a) in arid regions like Central Asia, water release by glaciers is fundamental to keep runoff sufficient during the dry summer months and b) at the end of this century the water contribution of glaciers will be drastically reduced and certain catchments will completely dry-out. This setting creates a complex set of future challenges in the areas of water management, energy production, irrigation, agriculture, environment, disaster risk reduction, security and public health.
Notably this also poses challenges in the field of climate services, as the lack of reliable data and commitment of the governments to fully integrate their observatory systems inhibits the sustainable development of the region. Exactly at this point, the project CICADA (Cryospheric Climate Services for improved Adaptations) is currently contributing to the improvement of the Cryospheric Climate Services in the Central Asian countries by installing modern monitoring stations, by training local students and researchers and using this information in order to provide climate scenarios and services for water runoff and natural hazards (e.g. GLOFs, debris flows). This is a prerequisite to allow early planning and adaptation measures within the water resource management (WRM) and disaster risk reduction (DRR) sectors. These scenarios and services have to be based on calibrated models linked to high quality baseline data.
The project is organized and partly financed by the University of Fribourg under the auspice of the World Glacier Monitoring Service (WGMS) with a large contribution of the Swiss Agency for Development and Cooperation (SDC).

Photo : Abramov glacier, Pamir Alay, Kyrgyzstan

ALTITUDINAL MASS BALANCE OF GLACIERS IN HIGH MOUNTAIN ASIA
Evan Miles1, Michael McCarthy1,2 Amaury Dehecq1,3, Marin Kneib1,4, Stefan Fugger1,4, Francesca Pellicciotti1,5

1Swiss Federal Research Institute WSL, 8906 Birmensdorf, Switzerland
2British Antarctic Survey, Natural Environment Research Council, Madingley Road, Cambridge, UK
3Laboratory of Hydraulics, Hydrology and Glaciology, ETH Zurich, 8093 Zurich, Switzerland
4Institute of Environmental Engineering, ETH Zurich, 8093 Zurich, Switzerland
5Department of Geography, Northumbria University, Newcastle, NE1 7RU, UK

ABSTRACT
Glaciers in High Mountain Asia have experienced intense scientific scrutiny in the past decade due to their hydrological and societal importance. The explosion of freely-available satellite observations has greatly advanced our understanding of their thinning, motion, and overall mass losses, yet our understanding of glacier accumulation and ablation rates is limited to a few individual sites. We combine recent assessments of ice thickness and surface velocity to adjust observed glacier thinning rates for mass redistribution, and estimate altitudinal mass balance across the region’s glaciers. We evaluate our results at glaciers with available field measurements (35 glaciers), then apply our approach to 5527 glaciers comprising 58% of mass for glaciers larger than 2 km2 in the region. The specific mass balance results allow us to determine the effective equilibrium line altitude for each glacier for the period 2000-2016, and enable us to partition the ablation budget.
Our results indicate that 40% of glaciers accumulate mass over less than 20% of their area. These unhealthy glaciers are concentrated in Nyainqentanglha, whereas accumulation area ratios of 0.7-0.9 are common in the Karakoram and Kunlun Shan regions. Our results suggest that at least 29% of regional ice volume cannot be sustained by current mass inputs, and 35% of glaciers are committed to lose at least half of their volume given the 2000-2016 mass balance distribution. In the Ganges-Brahmaputra basin, at least 41% +/- 6% of ice volume is unsustainable. However, we find that the most important and vulnerable glacier-fed river basins (Amu Darya, Indus, Syr Darya, Tarim Interior) are currently supplied with >50% ‘sustainable’ glacier ablation due to the extensive accumulation areas of the glaciers affected by the Karakoram Anomaly. Our results provide a baseline for the health of the High Asian ice reservoirs in the early 21st Century, and highlight the potential synthesis of distinct remote-sensing observations to understand patterns of recent glacier change.