Global News

Some four months ago, a devastating flood ravaged the Chamoli district in the Indian Himalayas, killing over 200 people. The flood was caused by a massive landslide, which also involved a glacier. Researchers at the University of Zurich, the WSL and ETH Zurich have now analyzed the causes, scope, and impact of the disaster as part of an international collaboration.

On 7 February 2021, a massive wall of rock and ice collapsed and formed a debris flow that barreled down the Rishiganga and Dhauliganga river valleys, leaving a trail of devastation. The flood took more than 200 lives and destroyed two hydropower plants as well as several roads and bridges. A large international team including researchers from the University of Zurich (UZH), the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) and the ETH Zurich came together immediately after the disaster and began to investigate the cause and scope of the flood and landslide. Their study used satellite imagery, digital models of the terrain, seismic data and video footage to reconstruct the event with the help of computer models.

Avalanche of rock and ice

Twenty million cubic meters of rock had broken off from Ronti peak in Chamoli district in Uttarkhand at about 5,500 meters above sea level, including a steep hanging glacier with about 5.5 million cubic meters of ice. The massive avalanche, made up of rock (80%) and ice (20%), hurtled down the valley and the narrow gorge. Resulting energy from the friction melted almost all of the ice and led to a devastating mudflow.

The international cooperation analyzing the extreme event was coordinated by GAPHAZ, a scientific group of leading experts on glacier and permafrost hazards in mountains. Holger Frey from UZH’s Department of Geography and GAPHAZ board member says: “The speed and breadth with which we analyzed the disaster is unprecedented. Only five years ago, having such extensive and high-resolution satellite imagery available so quickly was almost unthinkable.”

Chamoli

Pictured: Computer modeling of the Chamoli rock and ice avalanche (Ashim Sattar; UZH).

Research work started immediately

The UZH researchers have been working in the Indian Himalayas for several years and were contacted by the Indian government’s National Disaster Management Authority (NDMA) only hours after the event. In the days that followed, they were able to provide the Indian authorities with initial insights on how the disaster unfolded and the processes involved. “Among other things, our reports and assessments were used to plan the on-site investigation,” says Frey.

Hazardous hydropower projects

The deaths of more than 200 people, most of whom were non-local workers, and the destruction of the two hydropower plants added fuel to the ongoing debate about power plant projects in fragile alpine ecosystems. Following the devastating floods in Uttarakhand back in 2013, the hydropower industry was accused by the Supreme Court of India of having exacerbated the consequences of such floods with its practices.

“The Chamoli disaster sadly confirms that many hydropower companies operating in the Himalayas are not doing enough to survey and monitor the increasingly unstable alpine environment.” – Co-author Christian Huggel, Professor in the UZH Department of Geography and MRI Principal Investigator.

Impacts of climate change

The effects of climate change can also be felt below the surface. Temperatures inside mountains are rising in permafrost regions, increasing the likelihood of rockslides in alpine zones. Given the growing energy requirements in the Himalayan states, this problem is expected to get worse. “The Chamoli disaster was a rare extreme event,” says Holger Frey. “But it’s only a matter of time before the next such massive event will happen somewhere in the Himalayas.” With several additional hydropower plants in planning, fast and sustainable solutions are needed – as well as close collaboration with scientists.

“We must take advantage of the most advanced technologies and knowledge to better protect human lives and assets in the future,” Christian Huggel says. Such rare disastrous events cannot be ruled out for other mountain regions either, and they can have disastrous effects, especially in regions with relative dense infrastructure such as the Alps.


This media release was first published by the University of Zurich. The original release can be found on the University of Zurich website.


Read more: 


Cover image: Destroyed Tapovan Vishnugad hydroelectric plant after devastating debris flow of 7 February 2021. Image by Irfan Rashid, Department of Geoinformatics, University of Kashmir.

With global warming decreasing the size of New Zealand’s alpine zone, a University of Otago study found out what this means for the altitude-loving kea.

The study, published in Molecular Ecology, analysed whole genome DNA data of the kea and, for the first time, its forest-adapted sister species, the kākā, to identify genomic differences which cause their habitat specialisations.

New research based on information from the European Space Agency’s CryoSat mission shows how much ice has been lost from mountain glaciers in the Gulf of Alaska and in High Mountain Asia since 2010.

As our climate warms, ice melting from glaciers around the world is one of main causes of sea-level rise. As well as being a major contributor to this worrying trend, the loss of glacier ice also poses a direct threat to hundreds of millions of people relying on glacier runoff for drinking water and irrigation.

One tends to think of mountain glaciers as slow moving, their gradual passage down a mountainside visible only through a long series of satellite imagery or years of time-lapse photography. However, new research shows that glacier flow can be much more dramatic, ranging from about 10 metres a day to speeds that are more like that of avalanches, with obvious potential dire consequences for those living below.

Glaciers are generally slow-flowing rivers of ice, under the force of gravity transporting snow that has turned to ice at the top of the mountain to locations lower down the valley – a gradual process of balancing their upper-region mass gain with their lower-elevation mass loss. This process usually takes many decades. Since this is influenced by the climate, scientists use changes in the rate of glacier flow as an indicator of climate change.

Research published this month in BMC Ecology and Evolution explores the link between the size of white dead-nettle flowers and pollinator size and, using population genetic analysis, suggests that large flower size evolved independently in populations on different mountains in Japan as a convergent adaptation to locally abundant large bumblebee species.

The morphological compatibility between flowers and insects was given in the famous textbook example of Darwin's orchids and hawkmoths. As in this example, many studies have shown that geographical variations in flower size match the size of insects in each region. In other words, studies have shown 'flower-sized regional adaptation' in which large flowers evolve in areas pollinated by large insects and small flowers evolve in areas pollinated by small insects.

The United Nations Environment Program (UNEP) and partners call for case studies of initiatives to manage plastic waste in remote and mountainous areas.

Rapidly increasing amounts of plastic waste are polluting remote and mountainous areas across the world. The Secretariat of the Basel, Rotterdam and Stockholm Conventions (BRS Secretariat), in cooperation with Grid-Arendal and funding from the Governments of France and Norway, is implementing a project addressing the environmentally sound management of plastic waste in remote and mountainous areas. In this context, case studies are collected to inform future interventions and thus improve the management of plastic waste in remote and mountainous areas. 

The International Science Council invites comments on the Scientific and Technological Community Major Group position paper for the 2021 High-level Political Forum on Sustainable Development. We encourage the mountain research community to add a mountains perspective to this important document. Deadline 6 May 2021.

The International Science Council, together with the World Federation of Engineering Organizations (WFEO), leads the UN Major Group for Science and Technological Community (STC MG) for the Sustainable Development Goals (SDGs). Its mandate is to promote science and to strengthen the scientific basis of decision-making and governance of sustainable development.

An international research team including scientists from ETH Zurich has shown that almost all the world’s glaciers are becoming thinner and losing mass’ and that these changes are picking up pace. The team’s analysis is the most comprehensive and accurate of its kind to date.

Glaciers are a sensitive indicator of climate change – and one that can be easily observed. Regardless of altitude or latitude, glaciers have been melting at a high rate since the mid-​20th century. Until now, however, the full extent of ice loss has only been partially measured and understood. Now an international research team led by ETH Zurich and the University of Toulouse has authored a comprehensive study on global glacier retreat, which was published online in Nature on 28 April. This is the first study to include all the world’s glaciers – around 220,000 in total – excluding the Greenland and Antarctic ice sheets. The study’s spatial and temporal resolution is unprecedented – and shows how rapidly glaciers have lost thickness and mass over the past two decades.

Newsletter subscription

Login