UPSC IAS Prelims 2021: State of Himalayan Glaciers
Shrinking of the glaciers has been a phenomenon throughout the world with major glaciers in the world receding. In this article, read about the withering state of Himalayan Glaciers and the steps to contain it.
Worldwide, the glaciers have reduced considerably in mass and surface area since the little ice age period.
Shrinking of the glaciers has been a phenomenon throughout the world with major glaciers in the world-Melaspina in Alaska, Hubbard in Antarctica and even in Norway, Alaska and Patagonia have all been receding. Every continent offers unmistakable evidence of the recession of glaciers. This recession comes with its own attendant problems.
Like World, Indian glaciers too have been receding. Himalayan glaciers have been retreating and losing their mass faster than anywhere else in the world. Study of the last eight glaciers of the upper Rishiganga catchment Uttari Nanda Devi, Changbang, Ramni Bank, Bethartoli, Trishul, Dakshni Nanda Devi, Dakshni Rishi Bank and Raunthi Bank —had lost over 10% of their mass in less than three decades.
South-facing glaciers receded faster than north-facing ones, possibly because of longer exposure to insolation (solar radiation). It’s a different matter as glaciers also respond to climate and also dependent on their size and geometry.
Glacier recession in Himalaya
Image Source: The Diplomat
Glacier recession is best studied by the fluctuation of its equilibrium line. The equilibrium line which represents a balance between glacial accumulation and wastage, (the zone on a glacier where its mass lost is balanced by its mass gained over a year) swings in its altitude suggesting that glaciers in the Himalayas have responded to deprived precipitation conditions since 1980. Although temperatures have been increasing since the 1980s, glaciers are more sensitive to changes in precipitation.
The equilibrium line altitude fluctuated between 5,200m above sea level and 5,700m.
In the Himalayas, glaciers create a very different problem that includes
There 1,000 big and small lakes in the high mountains of Uttarakhand. Many of them are increasing in size. A lot of them do pose a threat of some kind.
Interestingly, there are not many GLOF (Glacial Lake Outburst Flood) that take place in Uttarakhand as they occur in Sikkim. This is because Uttarakhand has very steep slopes, and the water manages to find a way out.
Can glacial hazards such as GLOF be forecasted?
Image Source: The Outlook
It is not possible to completely prevent GLOF and other glacial hazards. But their potential to cause destruction can certainly be minimized. There are examples. The Lhonak lake in Sikkim is one of the largest glacial lakes in the country. Recently, scientists have found a way to let the waters of this lake slowly drain at the nearby river at a regulated rate, so that there is no flooding, and the pressure on the lake does not become unbearable. Such solutions can be applied in Uttarakhand, and some work is being done in this regard.
The first step in tackling the threat from these glacial lakes is to start monitoring the glaciers more actively and regularly. Of course, there is no need to monitor every glacier. Glaciers in one basin do not have remarkably different properties from another basin. Thus, if one or two benchmark glaciers in every basin are identified, particularly those that are more easily accessible, and their detailed studies done, then the results can be extrapolated to the rest of the glaciers in the basin or the state. It is important to get people and measuring instruments on the ground to monitor the situation. That is why accessibility becomes an important factor. Monitoring glaciers mean the measurement of the bathymetric changes, the mechanisms of expansion of the glaciers, changes in water levels, discharge balance, mass balance, and other attributes. It requires a lot of manpower and money.
• Forecasting can be based on several parameters.
Surveillance through Satellite forecasting humidity sensors, wind sensors and snow depth sensors, can be done by setting sensitivity zones. But relying only on satellites and remote sensing is not going to be enough.
• Structural geotechnical measures that includes Construction of channels for gradual and regular discharge.
It is possible to construct channels for gradual and regulated discharge of water from these lakes, which will reduce the pressure on them, and minimize the chances of a breach. At the same time, it also reduces the volume of water that goes into the flash flood. Also, alarm systems can be set up at the lakes, that will warn the community downstream whenever an overflow is likely to happen.
• Setting of comprehensive alarm systems. Besides classical alarming infrastructure consisting of acoustic alarms by sirens, modern communication technology using cell and smart phones can complement or even replace traditional alarming infrastructure. A preparatory response drill will also have to be worked out, like what India has done for cyclones and tsunami. Moreover, glaciology needs to be taken and instead as a part of policy intervention.
• Behaviour of fishes needs to be studied in detail as their movement and concentration can give a natural indication of such an event.
Moreover, Avalanches can be also be managed through mitigation. This includes
(a) Tree trunk support snow cover and provide an anchor to prevent the movement of the avalanche
(b) Snow drifting is slowed down.
(c) Tree canopy retains snow and releases it gradually to form a stable cover on the ground
(d) Forest canopy stabilises the snow.
5. Avoid travelling during daytime from 09.00 AM to 04.00 PM. Usually, avalanches get occur at this time.
6. Travellers and Trekkers should carry with them safety and sound alarm, as the time that one can remain trapped under an avalanche is about 10 to 15 minutes.
7. Snow Dogs, avalanche dogs like St Bernard are efficient in detecting people, trapped under the snow.
About the Author
K Siddhartha is a renowned Civil Services Preparation Mentor and Thought Leader. He has more than 20 years of experience and has mentored over 1550+ civil servants, film personalities, entrepreneurs, and policymakers. Mr. K Siddhartha is the author of 43 books & 116 research articles. He is frequently invited as a speaker on global platforms. (Views are personal)