IMD’s improved air quality models capture air pollution spike in Delhi

A very high-resolution city scale model has been operationalised for Delhi to identify air pollution hot spots and street-level pollution

The air quality forecast models for Delhi and the rest of India have improved according to India Meteorological Department, which will lead to better forecasts this year and identification of air pollution hot spots.

An image showing SO2 concentration in Delhi.(Sourced)

The October 15 forecast for India shows PM 2.5 concentrations ranging from 100 to 200 micrograms per cubic metre. The 24-hour safe standard for PM 2.5 is 60 micrograms per cubic metre.

When it comes to PM 2.5 concentrations in Delhi, the entire city seems to be impacted by concentrations of over 200 micrograms per cubic metre as per IMD’s ENFUSER model.

The air quality forecast model system for integrated modelling of atmospheric composition (SILAM) for India has been improved by implementing global emission inventories for coarse and fine particulate matter at 10 km resolution. “Earlier we had 50 km resolution. Plus, we have also added land cover and land-use data to obtain a better forecast,” explained Vijay Soni, a scientist at the air pollution division of India Meteorological Department (IMD).

A very high-resolution city scale model has been operationalised for Delhi to identify air pollution hot spots and street-level pollution. The model utilises air quality observations, road network, building, land use information, high resolution satellite maps, population data etc to generate forecasts. The results are being evaluated to capture pollution hot spots in Delhi, Soni said.

PM2.5 concentration in the country. (Sourced)

Now the air quality warning system will also provide forecasts for Lucknow, Kanpur and Varanasi at 2 km resolution. “For the Delhi model, we are using real time air quality data from ground monitors, traffic congestion data, road network data, etc. to identify hot spots. We will be able to share this information on our bulletins also,” he added.