The decadal pace at which glaciers are receding in Ladakh's Drass region, a key battleground during the 1999 Kargil war, indicates a grave threat to Himalayan glaciers. A recent study attributes this to the growing vehicular traffic in the region, which is also witnessing a massive build-up of military on both the sides of Line of Actual Control (LAC) since 2020.
The study published by the journal Environmental Science and Pollution Research is based on satellite images of 77 glaciers observed over two decades, from 2000 to 2020, in the Drass basin of western Himalaya. The glaciers studied ranged in size from 0.27 sq. km. to 14.01 sq. km, with an average size of 2.30 sq. km. The study reports that the glacier area decreased from 176.77 sq. km. in 2000 to 171.46 sq. km. in 2020, which is about 3% of the total glacier area.
"The pace of glacial recession varies greatly among glaciers ranging from 0.24% to 15%. The snout retreat for the period ranged from 30 to 430 meters. Debris cover had a significant impact on glacier melting, with clean glaciers losing 5% more than debris-covered glaciers. The average thickness change and mass loss of glaciers have been 1.27 to 1.08 meters," the study pointed out.
Climatologist Shakil Ahmad Romshoo and five research scholars, Khalid Omar Murtaza, Waheed Shah, Tawseef Ramzan, Ummer Ameen and Mustafa Hameed Bhat, participated in the study.
The analysis shows that glaciers at lower elevations receded by 4.10% whereas glaciers at mid- and higher elevations receded by 3.23% and 1.46% over the period observed.
The study found that heavy vehicular movement is the main cause for the rapid pace at which glaciers are receding in the region. Black carbon concentration ranged from 287 to 3,726 nanograms per cubic metre, with an average of 1,518 nanograms per cubic metre, "which is markedly higher compared to the black carbon concentration reported from other high-altitude locations in the Hindu Kush Himalayas".
"From 1980 to 2020, black carbon concentration has increased significantly from 338 nanogram per cubic meter in 1984 to 634 nano gram per cubic meter in 2020. It is inferred that the increasing black carbon concentration, due to the proximity to the national highway (NH), has significantly affected the glacier health," the study said.
The study points out that 17 glaciers situated close to the national highway showed higher glacier shrinkage (4.11%) and snout retreat (209 m) than the glaciers situated further away from the national highway, numbering 60, with glacier shrinkage (2.82%) and snout retreat (148 m). "Heavy vehicles are responsible for 60% of black carbon emissions," it added.
“Given the global nature of climate change, it is challenging to distinguish between the effects of civilian and military infrastructure and mobilisation on the environment and glaciers in the absence of data. However, when you consider the number of military vehicles on the Srinagar-Leh national highway, they make up a very small portion of the overall traffic on the road,” Mr. Romshoo told The Hindu. “In absence of any data or information on Indo-Chinese military mobilisation and manoeuvring in the greater Ladakh region, it’s not possible to reach any scholarly conclusion on the subject immediately,” he added.
Warning of the consequences, the study says: “It is feared that if the observed trends of the climate change continue in the future due to increased green house gas emissions and increase in black carbon concentration and other anthropogenic pollutants, glaciers in the Himalaya may disappear entirely, having a significant impact on regional water supplies, hydrological processes, ecosystem services and transboundary water sharing.”
