Probable mixing state of aerosols in the Indo-Gangetic Basin, northern India

To investigate the probable mixing state of aerosols in the Indo-Gangetic Basin, six different mixing cases, viz. external mixing, internal mixing, and four combinations of core-shell type mixing (black carbon, BC over dust, water-soluble over dust, BC over water-soluble and water-soluble over BC) have been considered. Composite single scattering albedo (SSA) have been computed for six cases for post-monsoon, winter and pre-monsoon seasons and are compared with the Aerosol Robotic Network (AERONET) retrieved SSA values. The most probable mixing state in the post-monsoon season seems either to be external mixing or water-soluble coating over dust and in the winter season, the external mixing seems to be the probable mixing state. However, in the pre-monsoon season, BC coating over dust seems to be the most probable mixing state. This type of mixing leads to enhanced absorption and needs future attention to better understand the aerosol radiative effect in this region.