Total river runoff, glacier melt and seasonality of flow in the Himalayan-Karakoram (H-K) rivers are projected to increase until the 2050s, with some exceptions and large uncertainties, according to a new study.
The study, ‘Glacio-hydrology of the Himalaya-Karakoram’, published in the journal Science has been led by Dr Mohd. Farooq Azam, assistant professor at the Indian Institute of Technology, Indore.
The study 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.
In a statement, the Science and Technology Ministry said the study shows that glacier and snow melt are important components of Himalayan-Karakoram rivers with greater hydrological importance for the Indus than Ganga and Brahmaputra basins.
“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 study said.
“The Himalayan river basins cover an area of 2.75 million km2 and have the largest irrigated area of 577,000 square kilometres, and 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,” said Azam.
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, he said.
Smriti Srivastava, a PhD student of Azam and co-author of the study, said, “Projected 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.