The footprints of climate change in the Himalayas and Karakoram mountain ranges have become very clear. This area is also called the Third Pole and glaciers are melting here, harmful phenomena are happening, snowfall patterns are changing. This is bad news for countries that depend on the rivers originating from these mountain ranges for their water supply. The latest study, ‘Glacio-Hydrology of the Himalaya-Karakoram’, published today in the journal Science, emphasizes that the total area of melting glaciers and the seasonality of flows are projected to increase by the 2050s. There will be some expectations and big uncertainties involved.
Dr Farooq Azam, Assistant Professor at the Indian Institute of Technology and lead author of the study, said, “The water needs of more than one billion people are met by glacial melting of the Himalaya-Karakoram mountain ranges. If a large part of the glacier melts during this entire century and there is a gradual reduction in the supply of the required amount of water, then this population will be affected. There is a region-wise change in the total impact on water supply every year. The impacts of glacier melt water and climate change on glaciers are more significant in the Indus basin than those of the Ganges and Brahmaputra basins, which are mainly fed by the waters of monsoon rains. These two river basins are more likely to be affected by climate change due to changes in rainfall patterns.
In this research paper prepared by analyzing various studies done in recent years, the effects of various climatic conditions on glaciers frozen in the Himalaya-Karakoram mountain ranges have been revealed. Along with this, it has also been told how it affects the rivers flowing below.
Jeff Kargel, a co-author of this research paper and from the Planetary Science Institute in the US, said, “To reach a more accurate understanding, the research team collected the findings of more than 250 study papers. Which seem to some extent to reach a consensus about the interrelationship between warming of the environment, changes in rainfall patterns and shrinkage of glaciers.
This study gives us a better understanding of the picture raised on a larger scale. It also tells us which are the areas where there is a need for regional, remote sensing and modeling research. The information gaps the researchers identified included a lack of accurate representations of the glacier’s total volume, a detailed understanding of the precipitation gradient in the region, and the role of permafrost, sublimation, glacier dynamics, black carbon and debris cover. Includes a detailed understanding of important studies on
Researchers have suggested adopting a multi-pronged approach to bridge these gaps. Level-1 includes an extensive observation network under which fully automated weather stations will be set up at selected glaciers. They have also suggested developing comparison projects to test the area and volume of glaciers, glacier dynamics, permafrost melting and ice and snow sublimation. In the meantime, it is recommended to apply this knowledge to build detailed models of glacial hydrology to reduce the uncertainties of future changes under Level 2.
The Himalaya-Karakoram river basin is spread over an area of 27 lakh 50 thousand square kilometers. It has the largest agricultural area of 577000 square kilometer which feeds five metropolitan cities namely Delhi, Dhaka, Karachi, Kolkata and Lahore. These cities have a population of more than 9.40 million and have the world’s largest hydroelectric power capacity installed at 26,432 MW in this region.
Dr Azam said, “While glaciers are melting rapidly due to climate change, which has affected the flow of rivers in the Himalaya-Karakoram mountain ranges, due to this, harmful events related to mountains are happening more than ever. The recent natural calamity in Chamoli district is shouting that no more development projects should be made on the weakened mountains of Himalayas.
Dr Azam said, “While glaciers are melting rapidly due to climate change, which has affected the flow of rivers in the Himalaya-Karakoram mountain ranges, due to this, harmful events related to mountains are happening more than ever. The recent natural calamity in Chamoli district is shouting that no more development projects should be made on the weakened mountains of Himalayas.
Dr. Azam has also co-authored another research paper ‘A Massive Rock and Ice Avalanche Caused by the 2021 Disaster at Chamoli, Indian Himalaya’. It has also been published today in the journal Science. This research paper describes what was the cause of the disaster that occurred in Chamoli in the Garhwal Himalaya region in February 2021, in which more than 200 people were missing or killed and two hydropower projects were seriously damaged. The researchers, based on satellite images, seismic records, modeling results and eyewitness videos, have revealed that a 27X106 cubic meter piece of rock and glacier ice broke off a massive amount of debris, which swept through the canyon walls. Scrubbing it up to 220 meters and brought with it very heavy stones. The hazard intersection and the location of the structures on the valley below added to the intensity of the disaster. This recognizes the need for sustainable development in these areas with adequate monitoring (in which these growing threats are included in the scope of consideration) and environmental impact assessment.
Dan Sugar, the lead author of the paper and of the University of Calgary, confirmed that there are no glacial lakes of any size large enough to cause flooding anywhere near the site.
He said, “The high-resolution images obtained from the satellite of the onset of the disaster help us to understand the event almost in real life. We saw clearly visible piles of dust and water at the height of a steep slope. It was the main source of massive landslides that triggered a series of disasters that caused heavy casualties and destruction.
There is a consensus among scientists related to both the papers that there is a need to further improve remote sensing and modeling research to bridge the marked information gaps. The risk of disaster is expected to increase in these extremely vulnerable areas. Whether it is the variations in water supply in the river or disasters like Chamoli, policy makers will also have to take into account the uncertainties associated with it while formulating development and water-related plans.
Joseph Shay, assistant professor at the University of Northern British Columbia and co-author of the Himalaya-Karakoram study, says, “The region’s major mountain ranges act as huge barriers to block moisture that comes with monsoons and winter storms. Huh. Basins adjacent to each other may also actually respond differently to these rapid variations in the environment.”
Smriti Srivastava, PhD student at the Indian Institute of Technology and co-author of the Himalaya-Karakoram research paper, says, “The predicted trends in the amount and seasonality of river runoff in the 21st century are consistent across a whole range of climate change scenarios. The total river runoff, the rate of glacier melt and the seasonality of the flow are projected to increase by the 2050s. There will be exceptions and huge uncertainties.