Fig. 7: Ratios of V/Pb at various locations illustrating the influence of coal combustion towards atmospheric aerosols across India.

Map illustrating the aerosol sampling sites and nearby coal-fired thermal power plants. The available V/Pb ratios were compiled from key locations, including Madhya Pradesh (Singrauli)9, Jharkhand (Jharia)11, Assam (Jorhat)10, West Bengal (Bandel and Kolaghat)1,8, Odisha (Bhubaneshwar)12, Andhra Pradesh (Vizag)16, Telangana (Hyderabad)15, Maharashtra (Trombay)14, Chhattisgarh (Raipur)13, Delhi4, and Uttar Pradesh (Kanpur)2. The red dotted line indicates V/Pb > 1. Aerosols demonstrating V/Pb > 1 can be sourced from coal combustion while those having V/Pb < 1 and ≪ 1 can be sourced from vehicular exhaust and high temperature industrial processes1. The base map has been adopted from the open-source online repository Opendatasoft (https://public.opendatasoft.com/explore/dataset/world-administrative-boundaries/export/) and the locations have been illustrated using ArcGIS Pro 10.8. The V/Pb ratios were plotted using Origin Pro 2024a and all the components were compiled in Adobe Illustrator 2021, to form the final illustration.