Frequency of extreme rainfall is likely to increase over the Western Ghats and Northeast river basins, while an increase in heavy rainfall intensity is projected over the Upper Ganga and Indus basins, a study by the scientists from Banaras Hindu University (BHU) has warned.
The research led by Prof RK Mall, Coordinator of the Department of Science & Technology-Mahamana Centre of Excellence in Climate Change Research (DST-MCECCR) at BHU, including Pawan Kumar Chaubey, used high-resolution simulated precipitation from Coupled Model Intercomparison Project-6 (CMIP6) experiments to examine the future hydroclimate extremes over the different River Basins of India.
The work supported under the Climate Change Programme of the Department of Science & Technology (DST), projected intense precipitation specially over the Western Ghats and Northeast river basins, and an increase in heavy rainfall intensity (14.3%) over the upper Ganga and Indus basins as well as intensification of severe droughts.
The study highlighting an agricultural drought in the lower Ganga basin due to a decline in mean rainfall was published in the journal Earth’s Future, American Geophysical Union (AGU).
It urged policymakers to devise strategies to cope with water surplus or scarcity.
The research elaborated that approximately 4% to 10% of the heavy rainfall is projected to increase over the western part of Indian River basins. In the mid-future, under certain carbon emission scenarios, a significant increasing change of about 30% precipitation per day was likely over the West flowing River Kutch & Saurashtra, including Luni, Indus, and Upper Ganga River Basins.
The results also showed that the significant changes in the frequency of hydro-climate extreme events may have a considerable impact on agriculture, health, and other socio-economic conditions of the society.
The major hotspots of highly populated cities identified for future urban flooding could help policymakers design appropriate basin-wise climate adaptation and mitigation strategies, including water and emergency services policies to minimise risk due to extremes in the basins.