From Jammu Kashmir to Everest and Ladakh, the risk of floods increases

As global temperatures continue to rise and glaciers melt faster, new research suggests the risk of flooding in the Himalayas of Ladakh, Jammu and Kashmir and the Tibetan Plateau could triple. Jammu and Kashmir are bracing for the risk of flash flooding after a spring heat wave accelerated the melting of glaciers in the Himalayas.

Glacial lakes in the Himalayas are becoming increasingly unstable and at risk of flooding, a trend evident in regions as distant and disparate as the Everest area and the arid highland deserts of Ladakh and Jammu and Kashmir.

As well as endangering communities and infrastructure, the projected increase in lake outburst flooding, detailed in the journal Nature Climate Change, could jeopardize water supplies in Jammu and Kashmir.

In recent decades, global rates of ice loss have accelerated rapidly. Many of those glaciers are located at the Third Pole of the Earth, the region that encompasses the Himalayas, the Tibetan Plateau, and surrounding mountain ranges.

The Third Pole is home to thousands of glaciers and glacial lakes that act as a huge water tower, supplying water to billions of people across Asia.

Both natural and man-made dams help control these water reserves, but increased melt rates have caused glacial lakes to swell and put pressure on local levees.

To better understand how ongoing warming trends will affect flood risks in the region, the scientists combined satellite imagery and topographic models. The analysis helped the researchers classify thousands of glacial lakes as high or very high risk.

According to researchers at the University of Potsdam, "the sustained melting of glaciers in the Himalayas has gradually generated more than 5,000 glacial lakes that are dammed by potentially unstable moraines."

Glacial Lake Outburst Floods (GLOFs) are extremely unpredictable, as they can be triggered by sudden pulses of meltwater. They can also be very destructive as they move downhill carrying debris that destroys lives, homes and the fragile landscapes that locals and wildlife depend on.

In addition, climate change is increasing the number of supraglacial lakes, small bodies of water that sit on top of glaciers, surrounded by rock debris and tend to exacerbate the overall instability of the ice.

Researchers from the University of Kashmir, Srinagar analyzed satellite data from 1969 to 2019. Using this and interviews with villagers, they reconstructed the flood of August 6, 2014, with computer models.

They found that the total area of ​​the glacier shrank by 45.6% in the 50 years to 2019, while Lake Gya almost quadrupled in size from 3 hectares to about 11 hectares in the same period.

Roughly 25% of the Gya glacial lake’s waters poured out in the 2014 flood, inundating about 4 square kilometres around the village. However, “a future worst-case GLOF could be 5.5 times larger than the 2014 event,” said Irfan Rashid, senior assistant professor at the University of Kashmir’s department of geoinformatics, and one of the authors of the study.

However, in recent years, the risk has increased markedly. Thus, an analysis of satellite images carried out in 2020 revealed that the number of glacial lakes had increased by 53% during the period 1990-2018. One of the reasons is the progressive global warming that the planet is experiencing that is causing the rapid melting of the glaciers.

If policy changes fail to curb global warming and temperatures continue to rise, models show that the number of glacial lakes at high or very high risk of flooding will increase from 1,203 to 2,963 by 2100.

The findings, based on 30 years of NASA satellite data published in the journal Nature Climate Change, will help researchers assess potential dangers to communities downstream of these often unstable lakes and help improve the accuracy of sea-level rise estimates by advancing our understanding of how meltwater is transported from glaciers to the oceans.

Glaciers are retreating on a near-global scale and this study gives scientists a clearer picture of how much water has been stored in lakes.

The research, embodied in the study, has analyzed the changes that have occurred during the last four decades in the Himalayan regions of India.

Unfortunately, the melting of glaciers in the Himalayas of Jammu Kashmir and Ladakh is not the only way that climate change is affecting this region. Simulations designed and carried out by researchers at the University of Potsdam suggest that thousands of lakes are at risk of causing dangerous flooding. This would happen because rising global temperatures continue to melt snow and ice.

Most glacial lakes are found in sparsely populated areas. However, communities living downstream could be affected by these floods, which also affect agricultural land and can damage infrastructure.

Support us to keep independent environmental journalism alive in India.

Keep Reading

Part 1: Cloudburst  in Ganderbal's Padabal village & unfulfilled promises