Nepal quake: Everest Sherpas warn of mountain risks
Everest Sherpas say they have seen potentially dangerous changes in their landscape after Nepal's 7.8-magnitude earthquake and aftershocks.
Nepal has more than 2,300 glacial lakes
29 May, 2015
They say they are living in fear of flooding and tumbling rock and ice because they have witnessed cracks in the ground and in glaciers.
Some glacial lakes have sunk underground with their outlets appearing at new place.
With temperatures increasing and the monsoon on the way, anxiety is rising.
Glacial lakes at risk of flooding following the 25 April earthquake
Hundreds of people from Sherpa villages fled to higher ground for safety on Monday night after a small glacial lake burst its banks, sweeping away two small bridges and a cowshed. It caused rumours that a major glacial lake had flooded.
Sherpas are members of an ethnic community that descended from Tibet hundreds of years ago - they use Sherpa as their surnames
A large number tend to be employed in helping climbers in expeditions or guiding trekkers, while others run lodges and tea houses for trekkers and mountaineers
Nepal has more than 2,300 glacial lakes and the most feared is Imja.
Government officials say a helicopter survey showed Imja was intact, but they admit a ground study of the area is yet to be done.
Imja Lake - the most feared - is intact, according to government officials
Locals say they are relieved about Imja but uncomfortable about other changes they have observed.
During a field visit this week a team from Sherpa villages found ice and debris in a place they should not have been.
"That was a place where we used to see certain flowers bloom," said Ang Chiri Sherpa, chairman of the Sagarmatha buffer zone users' group.
"But when we went to see what had happened, we saw an unusual, small glacier-like body of ice and soil and rock debris that could potentially fall on our village.
"We have no idea where this potentially dangerous thing came from."
With the summer season sending temperatures up and monsoon rains approaching, locals say they are increasingly worried.
"Rising temperatures mean glacier meltdown will accelerate and rains will mean moraines [rock and sediment deposited by a glacier] could become loose," said Tshering Sherpa, an official whose non-governmental organisation manages Everest base camp and the climbing route to the highest peak.
"All these could multiply the risk of outbursts, more so because the earthquake and continued tremors may have made the moraines of glacial lakes already weak.
"And then we have the recent horrifying experience of a lake breaking on Monday, even if it was a small one."
Most locals in the villages in the Everest region are still sleeping outdoors for fear of aftershocks and they say the concern over possible destabilised glacial lakes and glaciers are making them feel worse.
Pasang Sherpa, a lodge owner in Namche said the cries of women and children on Monday night still ring in her ears.
"We were all holding torches and running uphill crying and shouting in fear, it was miserable."
Scientists say they have not seen any evidence of risks so far but they also warn that things could change in these shaky times.
"Except for this little event of a lake which somehow released all its waters on Monday, there has been no evidence [of risk] as such," said Walter Immerzeel, assistant professor of physical geography at Ultrecht University in the Netherlands.
"But I think it's a fair concern on the part of Sherpas [because] you have those moraine dams which block those lakes and they can be destabilised by earthquakes and aftershocks."
Dr Immerzeel was in a team that recently produced research on Everest glaciers published this week in The Cryosphere journal of the European Geosciences Union (EGU).
"Avalanches and earthquakes can breach the dams, causing catastrophic floods that can result in river flows 100 times greater in the Kosi basin," the EGU said.
The Kosi basin stretches from the Everest region in the north to the Kosi river that joins the Ganges in India across the border in eastern Nepal.
Although the government and scientists say they have seen no immediate threat, members of the Sherpa community argue say their focus has been limited to the Imja glacial lake.
"So many other glacial lakes have formed in recent years and none of them have been studied, all they talk about is Imja," said Ang Chiri Sherpa.
Rishiram Sharma, head of the government agency responsible for monitoring and taking care of the glaciers and glacial lakes in the Nepalese Himalayas, said his office was trying to co-ordinate with other government agencies for an urgent field study.
"We understand the frustration of the Sherpa community and we will conduct a ground study at the earliest," he said.
The Sherpas from villages right below the glacial lakes and glaciers say they have formed a committee to monitor the threat themselves.
"Our committee will now make a dam to protect a village that was hit by Monday's flood from a glacial lake and then we will prepare a database of all the risky glacial lakes including those around the Khumbu glacier," said Ang Chiri Sherpa.
"We have heard enough of the government and foreign agencies' plans and projects to help us."
Previous material on this. The video below is of special interest
Risk of Nepal Glacial Lake Outburst
Risk of Nepal Glacial Lake Outburst
1 May, 2015
At least 10,000 people live directly in the path of the three very unstable glacial lakes, Imja Tsho, Thulagi and Tsho Rolpa. These areas include the dozens of towns on the main trekking route to Mt Everest Base Camp. These lakes are extremely vulnerable to Glacial Lake Outburst Floods (GLOF) from aftershocks following the 7.8 Ricther earthquake on Saturday, 25 April 2015.
GLOFs occur when earth structures damming large glacial lakes collapse. Formed out of deposited rocks and mud these dams are inherently unstable and can be ruptured by a single landslide or avalanche into the lake. Past floods have obliterated small hydro electric plants in their path. In 1980 a GLOF in north eastern Nepal devastated villages over 70km downstream.
The UN and World Bank have a number of development projects in place to improve warning systems about GLOFs, but they have not been adequately successful. Most towns have limited awareness of these risks and few (if any) have evacuation plans. Due to lack of resources many of the monitoring systems that did exist have degraded. The glacier lakes themselves serve as major tourist attractions, so locals’ incomes rely on remaining in endangered areas. In fact, as visitor numbers to Mt Everest have increased significantly over the past ten years, the local population living the the path of the Imja glacier lake has swelled.
Local District Disaster Relief Committees generally have very little knowledge about climate change or GLOF risk management. There is also insufficient coordination between different agencies for systematic information sharing on GLOF risk management and no efficient mechanism for communicating GLOF warnings effectively. UNDP Report September 2012
The natural moraine banks that form the dam for these lakes are unstable and are vulnerable to earthquakes. This instability is exacerbated by the fact that the volume of the glacial lakes has been increasing due to climate change.
Government and disaster management authorities have limited understanding and experience of managing growing climate risks, including current variability and the projected impacts of climate change, that are increasing the range and magnitude of disasters that Nepal is having to cope with UNDP Report September 2012
As these lakes only began forming in the late 1950s, they were not a threat when Nepal last experienced major earthquakes in the 1930s. Given the volume of water and steep terrain, World Bank flood models predict walls of water and debris up to 10 metres high, even 100km from the source. There is also a chain reaction risk where a comparably small lake, situated above larger lake, causes a sudden surge of water that then bursts the larger lake’s moraine dam.
Nouveau Eco created this risk map (above) because we want people in this zone, both local and international first responders, to be made aware of the risks facing them so that they can take steps to prevent further disaster in this already devastated region.
Nepal - I Have Seen the Earth Change
Solukhumbu is one of the 75 districts in Nepal. It gathers most of the 3300 glaciers and 2300 artic lakes of the country. Inhabitants witness huge climatic changes in the Everest area. The most striking being the fast glacier recession, which have given birth to new lakes where there was only ice and snow. Those lakes are a danger for the population, natural bombs, ready to explode. If the water overflows, it will sweep away inhabitants, bridges, houses and villages.
Not only that, but this
Monsoon rains increase risks of landslides in Nepal
Nepal needs to act quickly to reduce the destruction of landslides in earthquake-affected areas before the monsoon rains arrive, warn scientists
8 May, 2015
Nepal needs to urgently assess the risks from existing and potential landslides in earthquake affected areas before the monsoon rains come, say scientists who have produced a detailed map of landslide risks using satellite data.