On Monday, in the journal Nature, a team of scientists, led by Dr. Dan H Shugar published a paper mapping the glacial lakes of the world.
Their findings are extraordinary. Between 1990 and 2018, the physical number of glacial lakes has increased from 9,400 to 14,300 (a 53% increase) and the total global volume of glacial lake water has increased to an estimated 156.5 km3 (a 51% increase).
Glacial lakes have formed and expanded at the fastest rates in the highest of high altitude regions. The Himalayas, and therefore Nepal, is the epicentre.
For the work we enable in Nepal, there are two major implications:
Glacial Lake Outburst Flood: Each glacial lakes is held back by a stone, earth and ice formation called a Morraine. The Morraine acts like a dam, but many are fragile. They can collapse if one, or all of three things happen: (a) the ground ice that holds them together thaws; (b) if the volume of water they are holding back gets too large; or (c) if a large avalanche of snow or rock falling into the lake from the mountain above causes a tidal wave that overtops and destroys the morraine. Any of these things can cause a Glacial Lake Outburst Flood (GLOF) that sends water and rock hurtling down the mountainside and valley below.
Ending the supply of fresh water: GLOFs can cause immense damage to houses, farmland, bridges and roads and can of course kill the people, plants and animals in its path. But there is also a longer term problem, before any GLOF happens, water from glacial lakes seeps through its Morraine and graudally feeds the streams and rivers below. If the glacial lakes disappear, this year round supply of fresh water - that in some cases hundreds of thousands of people are reliant on - goes with it.
In the high mountains, above our project areas of Deusa and Waku in Solukhumbu, we know of a newly formed glacial lake, West Chamlang lake [which until recently was only known as Lake 464], that is in the shadow of the giant Mount Chamlang.
We want to send an expedition to West Chamlang lake
Mount Chamlang is just east of Mount Everest and yet has hardly ever been visited. Scientists who have been there to do preliminary studies of West Chamlang lake are concerned by the speed at which it has grown; they have called it a ‘ticking time bomb’. It seems to be a matter when, not if, a GLOF will occur.
A GLOF event at Chamlang would be a catastrophe for the farmers who live in the valleys below. More research into the size of the lake is desperately needed. Very little is known about its depth and therefore volume; we don’t know how fast it is growing. We don’t know how stable the snow and ice on the 2,000 metre high cliff that hangs above it is; and we don’t know how stable the Morraine that holds the lake back is.
A mapping exercise also needs to be done to ascertain how many people, plants and animals are at risk in the valleys below and a plan needs to be developed to work out how best to mitigate the risks.
This research is not easy, not without risk, and not cheap. These, however, are the expeditions of the 21st Century and we hope that those with deep pockets can be motivated to fund them.
Climate change is changing the world and we need to understand how, so that we can take action to save lives, both in the short and long term.
The Glacier Trust is ready to partner with anyone interested in a research expedition to West Chamlang lake. We have the local connections to the indigenous people who live below it and links to the major institutes in Nepal to pull a research team together.
If you want to know more, or are interested in supporting this work, please get in touch.