Back to news
30 Apr 2020 | Cryosphere

New study finds that crevasses in Himalayan glaciers can play a key role in influencing ice temperature

2 mins Read

70% Complete
The research team surveying Rikha Samba Glacier with GPR in 2015 (Photo: Tenzing Chogyal Sherpa/ICIMOD)

Glaciers in cold and arid climates, such as in High Mountain Asia, can warm up much faster than expected because atmospheric warming is resulting in meltwater moving into glaciers through surface crevasses.

Temperate ice is at the pressure melting point, which is the melting temperature of ice at a given pressure, and contains water. Glaciers in high mountains are often considered to consist only of cold ice (ice temperature below pressure melting point). A 2020 study published in The Cryosphere by ICIMOD and its partners shows that Rikha Samba Glacier in the Himalaya is polythermal, meaning that it consists of both temperate and cold ice. In the study, the team found that the transition period from cold to temperate ice in high-altitude mountain glaciers could be much shorter than earlier assumed.

“We found that the basal ice in the upper part of Rikha Samba Glacier could switch from cold to temperate in 50–60 years instead of the expected 100–150 years without the crevasse effect”, says Adrien Gilbert, lead author of the study from the University of Oslo, Oslo, Norway.

The research team combined field measurements made on Rikha Samba Glacier, a benchmark glacier monitored in Nepal, with remote sensing and numerical modelling to better understand the thermal structure of high-altitude mountain glaciers.

Originally, the team conducted ground-penetrating radar (GPR) surveys to estimate the ice volume of Rikha Samba Glacier. “To our surprise, in addition to the ice thickness, we saw large amounts of temperate ice within the glacier in the radar data”, explains Tika Gurung, ICIMOD, one of the authors of the paper.

A 4.5 km GPR profile of Rikha Samba Glacier
A 4.5 km GPR profile of Rikha Samba Glacier shows bedrock topography and large temperate ice zones within the glacier. (Source: Gilbert et al., 2020)

 

The team linked the temperate ice zones within the glacier with locations of surface crevasse fields. Numerical modelling demonstrated that deep water movement into the glacier through surface crevasses plays a crucial role in influencing the thermal structure of Rikha Samba Glacier. This indicates that similar processes apply elsewhere as well.

Rikha Samba Glacier is one of the benchmark glaciers being monitored as part of the Cryosphere Monitoring Programme in Nepal, being implemented by ICIMOD in collaboration with the Department of Hydrology and Meteorology, Government of Nepal; Kathmandu University; Tribhuvan University; and the Water and Energy Commission Secretariat.

Source Gilbert et al 2020
(Source: Gilbert et al., 2020)

 

Stay current

Stay up to date on what’s happening around the HKH with our most recent publications and find out how you can help by subscribing to our mailing list.

Sign Up
19 Jun 2018 Cryosphere
Institutional Recognition for Promoting Women in Glaciology Research in the HKH

Since its inception in 2011, the Cryosphere Initiative at the International Centre for Integrated Mountain Development (ICIMOD) has made a ...

21 Mar 2019 Gender in Koshi
Transforming gender and social perceptions in the brick industry

With rapid urbanization and demand for construction materials in Nepal, brick kilns have proliferated across the country, providing livelihoods to ...

12 Feb 2015 News
Women from Jumla learn to make bio-briquettes and cultivate herbs

During the training, the women learned the techniques for propagating Lott Salla (Taxus wallichiana) and Chirayita (Swertia chirayita) and for ...

25 Dec 2015 Himalica
P3DM in Myanmar

  A training on Participatory 3-Dimensional Model (P3DM) building was held in Letmaungwe, Kyaung Taung Village, Nyaung Shwe Township in Myanmar ...

24 Jul 2019 Cryosphere
Reassessing Tsho Rolpa glacial lake

Tsho Rolpa is a large, potentially dangerous glacial lake in Nepal that has been the subject of extensive research and ...

26 Dec 2016 News
Poster Presentation at the AGU

[caption id="attachment_7734" align="aligncenter" width="560"] Gunjan Silwal all set for her poster presentation.[/caption] Gunjan Silwal, ...

15 Apr 2015 News
Mobilizing early response for combating forest fire

The SERVIR-Himalaya Initiative of ICIMOD, in collaboration with theDepartment of Forests (DoF) of Nepal, carried out field level awareness campaign in ...

Workshop to improve brick kiln policy and technologies

A workshop on Brick Kilns Policy and Advocacy Network (PAN) was jointly organized by Climate and Clean Air ...