A GIS based emissions inventory at 1 km × 1 km spatial resolution for air pollution analysis in Delhi, India

In Delhi, between 2008 and 2011, at seven monitoring stations, the daily average of particulates with diameter <2.5 μm (PM2.5) was 123 ± 87 μg m−3 and particulates with diameter <10 μm (PM10) was 208 ± 137 μg m−3. The bulk of the pollution is due to motorization, power generation, and construction activities. In this paper, we present a multi-pollutant emissions inventory for the National Capital Territory of Delhi, covering the main district and its satellite cities – Gurgaon, Noida, Faridabad, and Ghaziabad. For the base year 2010, we estimate emissions (to the nearest 000ʹs) of 63,000 tons of PM2.5, 114,000 tons of PM10, 37,000 tons of sulfur dioxide, 376,000 tons of nitrogen oxides, 1.42 million tons of carbon monoxide, and 261,000 tons of volatile organic compounds. The inventory is further spatially disaggregated into 80 × 80 grids at 0.01° resolution for each of the contributing sectors, which include vehicle exhaust, road dust re-suspension, domestic cooking and heating, power plants, industries (including brick kilns), diesel generator sets and waste burning. The GIS based spatial inventory coupled with temporal resolution of 1 h, was utilized for chemical transport modeling using the ATMoS dispersion model. The modeled annual average PM2.5 concentrations were 122 ± 10 μg m−3 for South Delhi; 90 ± 20 μg m−3 for Gurgaon and Dwarka; 93 ± 26 μg m−3 for North-West Delhi; 93 ± 23 μg m−3 for North-East Delhi; 42 ± 10 μg m−3 for Greater Noida; 77 ± 11 μg m−3 for Faridabad industrial area. The results have been compared to measured ambient PM pollution to validate the emissions inventory.