Pakistan is ranked amongst one of the most affected country by climate change. Record high temperatures, drought or unusual rainfall, and floods are very common since a decade or so. With special reference to Gilgit-Baltistan, glacier lake outburst floods (GLOBF), flush floods, rockfall, avalanches, landslide and erosion have become synonymous with climate change. Rapid melting of Glaciers in the Karakoram area has been frequently debated due to supposed result of climatic change. Nevertheless, more in-depth research in the field gives slightly different picture regarding the perception of receding glaciers in the Karakoram chain. According to Rakesh Bhambri and other co-researchers, “Glaciers in the Karakoram exhibit irregular behavior. Terminus fluctuations of individual glaciers lack consistency and, unlike other parts of the Himalaya, total ice mass remained stable or slightly increased since the 1970s.”
In the previous two articles, an effort was made to explain the natural development in Shishper and Muchowar valleys, based on historical context as well as latest developments. The geographical location of this natural development and its potential implications downstream have also been highlighted to some extent. This article is in continuation of the same as the glacier continues to advance and surge along with the lake growing larger with passage of time.
Location of the natural Development
Shishper and Muchowar Glaciers are, among many, two of the off-shoots of Batura Wall in the western Karakoram Range in Northern Pakistan. Many glaciers, originating from Batura Peak extend south-east, south, and southwest. (See Map 1)
The confluence of both the valleys is located in central Hunza and can be accessed four kilometers away from the main Karakoram Highway in Hassanabad. A link road along the Hassanabad stream, built for the purpose of installing a two-megawatt hydro-electric powerhouse leads to the confluence of Shishper and Muchowar valleys, where snout of the expanding glacier can also be seen. However, as part of safety measures, the District administration has recently banned peoples’ movement into the valley by imposing section 144.
Shishper Glacier has stretched significantly towards south-west direction from north-east. Minor movement were observed for the last three years but since May-June this year, a drastic growth can be evidently observed both forward and upward. Sher Khan, a passionate climber and hiker, based on his latest observation narrated that “The peak rise of the glacier upward in vicinity of the snout is more than 600 feet. The constant upwards rise and forward movement is rapid and further layers or high tides on the glacier surface are evident at some distance in the Shishper valley”. While moving forward the middle part of the glacier has struck against the mountain in the front, left-side part moved towards Hassanabad and right-side part has expanded towards Muchowar Valley.
The research paper “Surge-type and surge-modified glaciers in the Karakoram” concluded that “The shift into and out of fast flow can occur in a matter of days or weeks and it may persist from a few months to several years. In a few cases surging continues for more than a decade. During the active or surge phase, large volumes of ice are transported from an upper reservoir zone into a lower, receiving zone. A wave of rapid thickening and thinning moves down-glacier, typically causing intense crevassing and over-riding of ice margin areas”.
Muchowar glacier, a parallel to Shishper is positioned to the north-west and is stretched towards south- east. Both the glaciers converged into one to form a confluence in the past but since a decade, Muchowar Glacier has detached itself from the other and has retreated about more than four kilometers. This has resulted in vacating a deep and long gorge at the mouth of the Muchowar valley.
How has the Lake formed?
The constant aloft and headlong expansion, Shishper Glacier has completely blocked water flow coming from Muchowar stream. This stream has been accumulating to form a giant lake. The stream earlier penetrated through or underneath the glacier bed and flowed downstream. Since the glacier, during its forward movement struck the opposite mountain foot in May-June last year thus overlying the open gorge, still water made its way through the glacier till mid-November this year. It was possibly considerable decrease in water flow from Muchowar side due to harsh winter and constant forward movement of the Shishper Glacier forced to block water flow.
Only experts in the relevant field can determine the actual cause of advancing glacier. However, local observers opine that there is unusual surge in one of the two tributaries (connecting glaciers locally called Faye Ghamo) which has triggered the advance. The said glacier is connected to Ultar Peak at its backside and it is worth-mentioning that a huge and mysterious abrupt development in Ultar Ravine in central Hunza turned into desert a centuries old pasture and caused three causalities in June last year.
The amount of water flowing into the lake is about 30 Cusic in winters. However, from April onwards, the inflow increases with increase in temperature and in May to September, the stream grows into a strong river gushing and roaring downstream. At present the lake has spread over a kilometer in length, near the same in width and more than 500 feet deep towards the side of the glacier.
Sher Khan observed that water level in the lake increased two feet every day during mid-January. “The lake water has penetrated into nearly half of the crevasses and has made the glacier surface very fragile. The crevasses are in spiral shape- thus don’t allow water to flow straight into the Hassanabad stream. Overall situation seems to be grim.” The water had topped over and released by January had the glacier not continued to up surged constantly. The glacier surface is so treacherous to tread upon that it is almost impossible to reach to the lake to further assess its continuous development.
The interesting phenomena is that with rising water level in the lake, glacier upsurge takes place simultaneously. In case water doesn’t release, the lake has the potential to expend more than four kilometers long towards its tail end by late spring and pose an impending catastrophic situation downstream in general and Hassanabad village in particular.
There is no expert opinion in hand on how the water will release. Some locals state that as the breath of the glacier is nearly a kilometer, it will withstand the water pressure and will not abruptly collapse. Water will, as it rises, penetrate through crevasses and release gradually. However, majority of the people, including those who recently visited the lake side are in panic about its disastrous effect.
Human settlements and major infrastructure such as electric power houses, irrigation channels, lifeline water supply lines, flour mills, all exist along the Hassanabad stream. It will be impossible to carry out any restoration work on above-stated infrastructure in summer as even in normal situation, the fast flowing stream with huge quantity of water doesn’t make it possible.
Nearly 70 house-holds in Hassanabad village can directly affect in a worst scenario in addition to their agriculture land, and infrastructure particularly on both sides of the stream. Karakoram Highway and mainly the bridge over the stream are also at threat. The KKH road is only source of land connectivity for central and upper Hunza and with China via Khunjerab Pass.
The location, nature and intensity of the natural development seems so huge that any mechanical effort to release water is not practical. Nevertheless, safety and dignified rehabilitation of the potential affectees of Hassanabad and beyond should be the top priority. Secondly continuous monitoring of the developments in Lake and glacier through installing monitoring cameras at the site is vital. Thirdly there should be an emergency plan for restoration of drinking water lines, irrigation channels, electricity and road. Neighboring China, being stakeholder under CPEC can also be kept in the loop with regard to restoration of the KKH in a worst scenario.
The author is a teacher by profession with interest in environment and human rights. He can be reached at firstname.lastname@example.org