hi INDiA Copyright 2020
Tribune News Service
Chandigarh, June 23
Snow and glaciers are melting rapidly in the Himalayan range due to climate change, altering water supplies in the rivers like Indus, Ganga and Brahmaputra that flow through the Himalaya-Karakoram (HK) ranges.
Total river runoff, glacier melt, and seasonality of flow in these rivers are projected to increase until the 2050s, with some exceptions and thereafter is expected to decrease, according to a study, “Glacio-hydrology of the Himalaya-Karakoram,” undertaken at the Indian Institute of Technology, Indore.
The research, led by Dr Farooq Azam, analyzed the results from more than 250 scholarly research papers to arrive at a more accurate understanding of the links between climatic warming, precipitation change and glacier shrinkage.
The HK region in South Asia, often called the water tower of Asia or the Third Pole is one of the most heavily glacierised mountain regions on Earth and understanding the response of HK rivers to climate change is crucial for almost a billion people who depend on these water resources.
Policymakers need to assess the current status and potential future changes of rivers for sustainable water resource management for agriculture, hydropower, drinking, sanitation, and hazard situations, according to a statement issued the Ministry of Science and Technology on today.
“The Himalayan river basins cover an area of 2.75 million square kilometers and have the largest irrigated area of 577,000 square kilometers along with the world’s largest installed hydropower capacity of 26,432 MW. The melting glaciers fulfils 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,” Dr Azam said.
Region-wide, the total impact on each year’s water supply varies. Glacier-melt water 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, he added.
Pprojected trends in river runoff volume and seasonality over the 21st century are consistent across a range of climate change scenarios. 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,” Smriti Srivastava, a PhD student and co-author of the study said
The study, funded by the Department of Science and Technology and has been published in the peer reviewed journal, Science. It identified gaps in understanding the impacts of climate change on the Himalayan water resources, and highlighted prospective solutions to bridge these gaps.
To address these gaps, the authors have recommended an expanded observation network that places fully automatic weather stations on selected glaciers along with developing comparison projects to examine glacier area and volumes, glacier dynamics, permafrost thaw, and snow and ice sublimation.