Emerging pattern of anthropogenic NOX emission over Indian subcontinent during 1990s and 2000s

The fossil fuel and bio–fuel burning in a developing country like India can have a significant impact on global climate. In the current work, we have set–up a more realistic, accurate and spatially distributed, all India, NOX emissions from different fuel combustion and industrial activities at 1°×1° grid resolution by incorporating the most recently available micro–level activity data as well as country specific emission factors (EFs) at high resolution. The emission scenarios and their trends are studied in a comprehensive way for approximately 593 districts (sub–region) in India. We have developed three scenarios to construct the possible range of past and present NOX emissions using Geographical Information System (GIS) based methodology. The total NOX emissions are estimated to be 2 952 Giga gram (Gg)/yr, 4 487 Gg/yr and 7 583 Gg/yr for three different base years, i.e., 1991, 2001 and 2011. NOX emission trends in India during 1990s and 2000s due to different major anthropogenic activities are estimated and their growth is discussed. A strong growth of NOX is found during 2000s as compared to 1990s. All major cities remain as top emitters of NOX. The present work depicts that the contribution of fossil fuel will gradually increase in coming years and will be around 91% by 2011. The present new gridded emission inventory will be very useful as an input to Chemical Transport Modeling study over Indian geography.