Research

Winter precipitation is observed in the northern parts of Indian subcontinent through December to March due to the passage of western disturbances embedded in the sub-tropical westerly jet stream. This precipitation is a primary irrigational source for agriculture and plays a critical role in replenishing the water resources in the northern plains and maintaining the snow cover of the Himalayan glaciers. Being thickly populated, North India is prone to heavy destruction due to the increased frequency and intensity of extreme precipitation events such as, flash floods, cloudbursts, landslides, avalanches, etc. We aim to understand and simulate the winter precipitation dynamics and its key mechanisms over the Himalayas at a range of resolutions, including cloud-resolving scales. 

Cold waves are extreme weather events prominent during the winter season (November to February) of India. A cold wave is characterized by a sharp drop of air temperature near the surface, steep rise of pressure and strengthening of wind speed associated with hazardous weather. Cold waves are most commonly associated with the passage of a western disturbance (WD) although several other factors such as ENSO, Siberian High (SH), low-pressure system over Arabian sea plays critical role. Cold wave has detrimental effect on the health of human beings as it can increase the mortality rate owing to the socio-economic conditions. In addition to this cold wave also has serious impacts on agriculture, livestock, marine and several other sectors. We aim to understand and predict the influence of cold waves over the north Indian region.

The atmospheric aerosols demonstrate spatial and temporal heterogeneity across the different part of India due to variable climatic conditions, intense urbanization and industrialization in the past decades. The abundances in aerosols concentrations can cause severe impacts on various sectors such as the ecosystem, atmospheric visibility, human health. Using state-of-the-art atmospheric modellig, available in-situ and remote sensing observations and global reanalyses, we aim to understand the physical process responsible for DSs and their influence on regional dynamics. We further develop the regional early warning system using numerical models to mitigate their impacts.