Climate Witness: Ang Tshering Sherpa, Nepal

Posted on
17 septiembre 2007
My name is Ang Tshering Sherpa and I was born on 15 November 1953 in a picturesque Himalayan village of Khumjung (3790m) in the Solu-Khumbu district.  It is one of the famous Sherpa villages on the way to Mt Everest. 

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I spent most of my childhood in Khumjung as a pupil of Sir Edmund Hillary’s first school, and consequently I was fortunate enough to be the one of the first batch of graduates. I also studied Buddhist scripture with my grandparents at the Tengboche monastery.

It has been more than 35 years that I have been working in the mountain tourism sector.  Twenty-five years ago, in 1982, I established Asian Trekking Pty. Ltd, which organizes trekking and tour packages, mountain expeditions in the Himalayas, including Everest, and other activities related t mountain tourism. 

Over the years, Asian Trekking has grown into one of the biggest operators in Nepal and Tibet. We are also the general sales agent of China-Tibet Mountaineering Association. Besides being the Chairman of Asian Trekking, I am also the president of the Nepal Mountaineering Association, as well as the Honorary Consul of Belgium to Nepal.

Retreating glaciers
My personal and professional experiences have been witness to vast changes in mountain areas, especially in Everest region. Most noticeable in my lifetime has been that glaciers are rapidly retreating and new glacial lakes have formed where there was only ice and snow before.

When I was a child, I could easily cross the Ngusumba Glacier near Mt. Cho Oyu with our herd of yak.  Today, the glacier has been transformed into innumerable small lakes. We also used to cross Lho La pass (6026m), situated on the western ridge of Mt Everest, on our way to trade in Tibet. Today, all that remains of this huge ramp of ice and snow are precarious ceracs clawing desperately to the top of rocky cliffs. In both cases it is no longer possible to use this historic route.

Over the years, I have seen new glacial lakes form, and their size has increased dangerously. Before 1960, Imja Lake (5000m) did not even exist. It first appeared in 1962 as a small pond. Now, the lake is almost 1.6-kilometres long and could burst at any moment.

On 4 August 1985, another glacial lake, called Dikcho Lake (4365m), burst resulting in huge loss of live, property and infrastructure. Imja Lake is twice the size of Dikcho Lake and is located upstream of the famous Everest trail which takes people the highest mountain in the world. If we allow Imja Lake to burst it would be the most shameful example of our ignorance to our rapidly changing world.

A similar trend is seen on the Ngusumba Glacier and others throughout the Himalayan region. These small lakes will eventually follow Imja Lake’s example and grow into dangerously big lakes. I dread thinking about the calamities and human loss when these lakes burst.

Changing weather
Besides potential glacial lake outburst floods, our mountaineering profession is also facing problems due to unpredictable weather condition. Just over a decade ago, the appropriate climbing season for mountaineering used to be September, October and November. Today, it has shifted to late May and is shifting later and later into the summer. The weather has become unreliable — it snows when it is time to rain, and rains when it should snow. Because of this, there has been increase in the rate of accidents during mountaineering expeditions.

Another danger to our profession is the rapid rate at which snow melts. Only a few years ago, it used to take about two months to melt a foot of snow, whereas nowadays it takes only a couple of weeks to melt twice as much snow. This phenomenon is very obvious when we set up our camps. We constantly find ourselves adjusting and relocating our camp sites as the snow around our tents melt. Another threat we find at camp sites are the huge boulders scattered on the glaciers which over a few weeks find themselves raised on icy platforms, ready to tumble down on to the tents below.  

I don’t think local pollution and tourism is the cause for this trend. I think it is because of global warming.

Act now!
The leaders of the world should come up with appropriate policies to deal with this. However, it is our responsibility to act now to address the issues, especially of Imja Lake.

It is very important that water in the lake is drained properly so that potential danger is reduced. It is essential for us to take immediate measures to reduce the water pressure on the lake and take similarly drastic measures in other critical lakes, like we have done to secure Tsho-Rolpa Lake. We also have to keep a cautious eye on new glacier lakes that are forming.

Our biggest asset is our environment, and Nepal’s natural beauty belongs not only to us but to the entire world and the future generations. I pride myself on teaching these values to my own children but I fear the day that they will have to tell their own children that it was our generation that did nothing to stop its destruction. 

We Nepalese are doing as much as we can to resolve these issues, but without international recognition of the problems and support to resolve them it is almost futile for us to tackle such globally rooted issue.


Scientific review

Reviewed by:  Dr Om Bajracharya, Nepal Department of Hydrology and Meteorology

The observation on the development of glaciers and glacier lakes in the Everest region by Ang Tshering Sherpa is noteworthy during the time of his 35 years working experience in mountaineering trekking expedition. I agree with Mr. Sherpa’s remark that the size of Imja glacier lake is increasing since its development recorded in the year 1953.

The topographical map of 1953–1963 showed that there were supra glacial lakes on the surface of Imja Glacier and the area of the lake was found to be 0.03km2 only.  Field investigation of Imja Glacier lake in 1999 showed the lake area has increased to roughly 0.75km2, with an average growth rate of 0.02km2 /year.

Analysing temperature recorded in the last 30 years, it is obvious that the temperature is increasing rapidly.  The average warming in annual temperature between 1977 and 1994 was 0.06 ºC/yr (Shrestha et al. 1999).  The warming phenomenon is more obvious at high altitude and is even more noticeable in winter seasons.

Temperature data of Kathmandu (1940 to 1970) further shows that temperature was in decreasing trend and thereafter noticed increasing trend. It can be concluded that the climatic variations in Nepal are very much connected to global climatic changes. This suggests that the Himalayas, being high regions of the globe, are sensitive to and affected by climate change. 

All articles are subject to scientific review by a member of the Climate Witness Science Advisory Panel.