Air pollution is a growing problem for of the most world cities. In response to the deteriorating urban health and growing civic demand, scientists and policy makers have recognized the need for an integrated air quality management, for better urban planning and clean air. A majority of the existing tools for integrated assessment are complex and data-intensive. There is a need to develop an organized knowledge base to feed into a robust decision support tool that takes into account the various institutional and technical challenges in developing countries.

The SIM-air family of tools “Simple Interactive Models for better air quality” are developed with one objective – make use of the best available information with the academic, government, and non-governmental bodies, in order to support integrated air quality management, whose schematics are presented to the right. The tools are designed to collate the necessary information, to estimate key parameters (e.g. emissions from various sources) and to simulate the interactions between emissions, pollution dispersion, impacts, and management options in an environmental and economic context.

Please cite appropriately and if you have any questions on the tools, suggestions to improve the tools, or want to share your experiences while using the tools, please email to

So far, the SIM-air family of tools include the following

  • The SIM-air Model (V1.3, V2.0, and V3.0) – An integrated air pollution analysis tool to go from estimating emissions to pollution to impacts for a set scenario and also perform optimization among options for better air quality; Browse under the “Modeling Tools/SIM-air” tab to access the case studies from various cities
  • VAPIS – Vehicular Air Pollution Information System – A vehicular emissions calculator to estimate and compare emissions inventory; including a repository of emission factor databases
  • Air Quality Index Calculator – A simplified calculator, which is commonly used in a number of cities across the world, designed to plug your monitoring data to estimate either real time or forecasted AQI (Click here for an infograph on how to calculate AQI)
  • ATMoS Dispersion Model – The Atmospheric Transport Modeling System – A (fortran language based) simplified lagrangian dispersion model to generate transfer matrices for multiple source and multiple pollutant types; for direct input to the SIM-air model

Along with the tools, we maintain SIM-air working paper series published in addition to our peer-reviewed publications, where methodologies, applications, and references on the air pollution modeling, emissions inventories, source apportionment, air quality management, and co-benefits analysis from cities and regions are published. The series is an open-resource and available for free. However, please cite the articles appropriately when used.

Latest in the series are

  • SIM‐39‐2012 ‐‐ Urban air pollution and co-benefits analysis for Indian cities
  • SIM‐38‐2012 ‐‐ A Multi‐pollutant emissions inventory for National Capital Region of Delhi, India
  • SIM‐37‐2012 ‐‐ An Analysis of health & carbon co‐benefits for Pune, India
  • SIM‐36‐2011 ‐‐ Air Quality Forecasting System for Cities: Modeling Architecture for Delhi, India
  • SIM‐35‐2010 ‐‐ AQI for Delhi, India: Trend Analysis & Implications to 2010 CW Games
  • SIM‐34‐2010 ‐‐ Air Quality Index (AQI): Methodology & applications for public awareness in Cities

Regular updates on the SIM-air tools and the SIM-air working paper series are sent to the members of the SIM-air mailing list. If you want to join the list, please send an email to with a brief description of your research.


Simple Interactive Models for better Air quality (SIM-air)