Air pollution respects no boundaries; therefore, pollutant concentrations over any region are influenced by both local emissions and transboundary pollutant transport. It is thus essential to simulate the movement and distribution of pollutants to understand the processes that govern their spread and to design effective control strategies to reduce their levels.
Atmospheric concentrations of air pollutants can be modelled using Chemical Transport Models (CTMs) or Reduced Complexity Models (RCMs). At CSTEP, we are working on developing models at both ends of this spectrum. We are developing CTMs setups that can precisely predict pollutant concentrations, transboundary contributions, source apportionment of PM₂.₅ and calibrating RCMs for any given region. CTMs provide a more accurate representation of atmospheric processes but are computationally intensive which makes them unsuitable for evaluating multiple emission control scenarios efficiently.
In contrast, RCMs offer faster computation and require fewer resources, albeit with slightly reduced accuracy. Also RCMs needs to be well-calibrated against measurements and CTMs and locally adapted. To address this need, we are developing Rapid Estimation of Air Concentrations for Health over India (REACH-India), an RCM in collaboration with Dr. Medinat Akindele and Professor Peter Adams of Carnegie Mellon University. When used with an emissions inventory, REACH-India can estimate changes in PM₂.₅ concentrations resulting from marginal changes in emissions under different reduction scenarios. These computations can be performed on a regular PC with minimal training. To further streamline the process, we are developing the REACH Policy Assessment Tool, which will be publicly released in early 2026. This tool is designed to support policymakers and researchers in making informed decisions to reduce air pollution and improve public health.
Over the past two years, we have also been involved in capacity-building efforts, conducting a modelling workshop and full-day tutorials as part of our annual flagship event, ICAS 2025:
By integrating both CTMs and RCMs, we aim to enable effective air quality management at various spatial scales.
Interested in beta testing? Please contact piyush.bhardwaj@cstep.in
