Glacier-Related Hazards Along the International Karakoram Highway: Status and Future Perspectives

Abstract

The China–Pakistan international Karakoram Highway passes through the core area of the “Karakoram Anomaly,” whose glaciers have maintained or increased their mass during a period when most glaciers worldwide have receded. We synthesized the literature and used remote-sensing techniques to review the types, distribution, characteristics, causes and frequency of major glacial hazards along the Karakoram Highway. We found that the glacier-related hazards could be divided into direct and indirect hazards, including glacier surges, glacial lake outburst floods, and glacial floods, which are concentrated in East Pamir and the Hunza River Basin. In the past 100 years, hazards from glaciers surges and glacial floods only occurred once and twice, respectively, which appear suddenly, with the hazard-causing process being short-lived and occurring mainly in the summer. Glacial lake outburst floods mainly occur in the spring and summer in the Hunza River Basin. Among these, ice-dammed lakes have the highest frequency of flooding, their formation and outbursts being closely related to the sudden advancement of surge-type glaciers. Under the background of global climate warming, we speculate that the glacier surge cycle may shorten and the frequency of the formation and outbursts in the glacial lakes may increase. In the future, we should combine models and new field observations to simulate, and deepen our understanding of the physical mechanisms of different glacier-related hazards. In particular, on-site monitoring should be carried out, to include the evolution of glaciers subglacial hydrological systems, the thermal state at the base of the glaciers, and the opening and closing of drainage channels at the base of the ice dams.

A regionally resolved inventory of High Mountain Asia surge-type glaciers, derived from a multi-factor remote sensing approach

“…The source of many large glacial lake outburst floods (GLOFs) in the Karakoram can be traced back to lakes which have formed behind the advancing terminus of a surge-type glacier (Hewitt and Liu, 2010;Bhambri et al, 2019). The timing and magnitude of the drainage of such lakes is difficult to predict because of the active nature of the lake's ice dam, but several GLOFs may occur from the same lake during the active phase of the damming glacier (Round et al, 2017;Gao et al, 2021;Bazai et al, 2021). The recent surge and associated glacial lake formation alongside Shishper Glacier (Bhambri et al, 2020;Muhammad et al, 2021) is just one example of the threat posed by surge-related hazards to high-mountain infrastructure such as the international Karakoram Highway -a route which provides a vital link to mountain communities in Tibet/southwest China and Pakistan (Ding et al, 2018).…”

A regionally resolved inventory of High Mountain Asia surge-type glaciers, derived from a multi-factor remote sensing approach

“…The source of many large Glacial Lake Outburst Floods (GLOFs) in the Karakoram can be traced back to lakes which have formed behind the advancing terminus of a surge-type glacier (Hewitt and Liu, 2010;Bhambri et al, 2019). The timing and magnitude of the drainage of such lakes is difficult to predict because of the active nature of the lake's ice dam, but several GLOFs may occur from the same lake during the active phase of the damming glacier (Round et al, 2017;Gao et al, 2021;Bazai et al, 2021). The recent surge and associated glacial lake formation alongside Shishpare Glacier (Bhambri et al, 2020) is just one example of the threat posed by surge-related hazards to high mountain infrastructure such as the International Karakoram Highway -a route which provides a vital link to mountain communities in southwest China/Tibet and Pakistan (Ding et al, 2018).…”

Spatiotemporal variations in runoff and runoff components in response to climate change in a glacierized subbasin of the Upper Indus Basin, Pakistan

“…The selected study area is very important for the economic development of both Pakistan and China because part of the trade route that starts from China is passing through this region. This route is also known as the China-Pakistan Economic Corridor (CPEC) and it is an integrated part of the "One Belt One Road" initiative policy (Gao et al, 2021). The study area is highly glaciated and has several potentially dangerous glacial lakes.…”