Take Tiered Approach To Tackle Climate Change Effects In The Himalayas: Study
NEW DELHI — Climate change is causing river runoffs and melting of glaciers located in the Himalayan range, and the seasonality of flow in rivers in the region like the Indus, Ganga, and the Brahmaputra will continue to increase till the 2050s, says a new study which suggests a tiered approach to tackle the crisis.
The study stated that “total river runoff, glacier melt, and seasonality of flow in these rivers are projected to increase until the 2050s, with some exceptions and large uncertainties.”
The Ministry of Science and Technology on June 23 said, quoting the new study, that snow and glaciers are melting rapidly in the Himalayan range due to climate change, altering water supplies in rivers like the Indus, Ganga, and the Brahmaputra in the Himalaya-Karakoram (HK) ranges.
The Himalaya-Karakoram region in South Asia is often called the water tower of Asia or the Third Pole. It is one of the most heavily glacierized mountain regions on Earth. Understanding the response of the Himalaya-Karakoram rivers to climate change is crucial for almost 1 billion people who partly depend on these water resources.
Azam gathered the results from more than 250 scholarly research papers to arrive at a more accurate understanding — something approaching a consensus — of the links between climatic warming, precipitation change, and glacier shrinkage.
The study shows that glaciers and snowmelt are essential components of Himalaya-Karakoram rivers with greater hydrological importance for the Indus than Ganga and Brahmaputra basins.
“The Himalayan river basins cover an area of 2.75 million square kilometers and have the largest irrigated area of 577,000 square kilometers, and the world’s largest installed hydropower capacity of 26,432 MW,” said Azam. “The melting glaciers fulfill the water requirements of more than a billion people of the region who will be affected when much of the glacier ice mass melts throughout this century and gradually stops supplying the required amount of water.”
“Region-wide, the total impact on each year’s water supply varies,” he added. “Glacier meltwater, and climate change impacts on glaciers, are more crucial for the Indus basin in comparison to the Ganga and Brahmaputra basins, which are predominantly fed by monsoon rains and are affected mainly due to the changing rainfall patterns.”
“Projected trends in river runoff volume and seasonality over the 21st century are consistent across a range of climate change scenarios,” said Smriti Srivastava, a Ph.D. student of Azam and co-author of the study. “Total river runoff, glacier melt, and seasonality of flow are projected to increase until the 2050s, and then decrease, with some exceptions and large uncertainties.”
The work supported by INSPIRE Faculty fellowship funded by the Department of Science and Technology (DST) identified gaps in understanding the impacts of climate change on the Himalayan water resources. It highlighted prospective solutions to bridge these gaps.
Policymakers need to assess rivers’ current status and potential future changes for sustainable water resource management for agriculture, hydropower, drinking, sanitation, and hazard situations.
The authors recommend a tiered approach to address the identified gaps: Tier-1 includes an expanded observation network that places fully automatic weather stations on selected glaciers. They also suggest developing comparison projects to examine glacier area and volumes, glacier dynamics, permafrost thaw, and snow and ice sublimation. Meanwhile, Tier-2 recommendations implement the knowledge of these studies in detailed models of glacier hydrology to reduce the uncertainty in projections of future change.
(With inputs from ANI)
(Edited by Anindita Ghosh and Ojaswin Kathuria)