Abstract

Atmospheric aerosols influence the regional hydroclimate through several pathways. Aerosol radiative forcing affects the monsoon, heatwaves, and air quality over the South Asian region. The transport of absorbing aerosols like black carbon and dust to the Himalayan-Tibetan region raises a serious concern for the seasonal cycle of snow and thus the health of glaciers. The deposition of absorbing aerosols on the snow decreases its albedo and traps more radiation in the snowpack. This anomalous absorption increases the surface temperature and enhances the snow melt and runoff over this region. Though aerosol loading decreases with elevation, the aerosol-induced warming and snow cover change further strengthen the elevation dependence of warming trends observed over these high mountain regions due to global warming. Hence, the aerosol-induced snow albedo feedback has direct consequences for the increasing trend in surface temperature and depleting water resources over the Himalayan-Tibetan region. This forcing pathway is investigated using a regional climate model coupled with aerosols and snow modules and the effects of aerosol deposition on the hydrological cycle and regional climate over the Himalayan-Tibetan region will be discussed in detail during the presentation.

About speaker:

Dr. Vijayakumar S. Nair has been working as a Scientist at SPL-VSSC since 2011. He received his PhD from SPL in 2010. His research interests focus on Climate change, regional climate modelling, and Aerosol-Climate interactions. He as been authored and co-authored in 67 research papers published in peer-reviewed journals.He is an associate Editor of the Journal of Earth System Science and a reviewer of various peer-reviewed journals. He received several awards, including the prestigious Swarna Jayanti Fellowship in 2020.