Team members: Prof. Aditi Bhadra, Prof. Arnab Bandyopadhyay, Liza G. Kiba, Ngahorza Chiphang, Pooja Mishra (Department of Agricultural Engineering)

URL to published work

http://dx.doi.org/10.1007/s12665-023-11086-9

The climate in the future is expected to become warmer and wetter under most scenarios and as temperature determines the fraction of precipitation that will fall as snow, regions having large portion of runoff contribution from melting of snow is more susceptible to change in temperature. A slight shift in the climatic pattern due to rising temperature and varying precipitation is expected to largely affect the mountainous regions and therefore, the Himalayan region being highly dependent on snow storage is susceptible to suffer from the effects of climate change the most.

To improve the understanding of the influence of climate change on the future runoff in the Indian Himalayan Region (IHR), projected climatic variables (temperature and precipitation) and projected snow parameters (snow depth, SWE, and snow cover %) were incorporated in the Spatially Distributed Snowmelt Runoff Model (SDSRM), a hydrological model developed by researchers from NERIST, and future runoff under two climatic scenarios, RCP 4.5 and RCP 8.5 for Mago river basin (Eastern) and Alaknanda river basin (Western) of the IHR were simulated.

The result obtained from this study suggested that with the projected increase in temperature and precipitation, snow will decrease in both the river basins as the rise in temperature will lead to more melting of snow which will ultimately result in higher runoff. Higher percentage change in snow parameters was predicted in the Eastern Himalayan basin as this region is expected to have no to very less snow by the end of this century. Both the river basins are projected to undergo similar change in runoff in the future. By the end of 21^st century, a rise in mean temperature of about 2.4 °C may result to an increase of 13.17% of future runoff while an increase of about 4.5 °C may result in 36% increase in future runoff under RCP 4.5 and RCP 8.5 respectively, in both the river basins. This expected increase in future runoff urges for better management and conservation of the resources in the IHR.