Ladakh glacier retreat due to warming, low winter precipitation, finds study

The study is based on four years of field observations

Whether Zanskar Valley in Ladakh or the Zemu in Sikkim, India’s overall loss of glacier volume between 1963 and 1997 was about 23%. Seen here is a camp in the Zanskar range. Photo: Special Arrangement

The Pensilungpa Glacier located in Ladakh’s Zanskar Valley is retreating due to increase in temperature and decrease in precipitation during winters, a recent study has found. Since 2015, the Wadia Institute of Himalayan Geology (WIHG) at Dehradun, an autonomous body under the Department of Science and Technology, has been working on various aspects on glaciology – glacier health (mass balance) monitoring, dynamics, discharge, past climatic conditions, speculation for future climate change and its impact on glaciers in this region. A team of scientists from the institute ventured to study the less explored region of the Himalayas at Zanskar in Ladakh.

Stake networking

”Based on field observations for glacier mass balance collected via stake networking... over the glacier surface since 2016-2019, they assessed the impact of climate change through the lens of past and present response of the Pensilungpa Glacier, Zanskar Himalaya, Ladakh,” the study said. In stake networking, stake made of bamboo, is installed on the glacier surface using the steam drill for mass balance measurement.

Rate of decline

The study also said that field observations for four years (2015–2019) showed that the glacier is now retreating at an average rate of 6.7 plus/minus 3 metre per annum. In the study published in the journal Regional Environmental Change, the team attributes the observed recessional trends of the Pensilungpa Glacier to an increase in the temperature and decrease in precipitation during winters.

Debris cover

The study also points at the significant influence of debris cover on the mass balance and retreat of the glacier's endpoint, especially in summer.

Furthermore, the mass balance data for the three years (2016–2019) showed a negative trend with a small accumulation area ratio.

The study also suggests that due to continuous rise in the air temperature in line with the global trend, the melting would increase, and it is possible that the precipitation of summer periods at higher altitudes will change from snow to rain, and that may influence the summer and winter pattern.