Amid all these concerns, the city turned to drones to monitor hotspotsexcept those spraying water to suppress PM2.5. “Drones are useful in gaining access to areas that are difficult to monitor manually, such as crowded urban areas or industrial regions,” says R. Subramanian, head of air quality at the Center for Study of Science, Technology and Policy, a think tank based in Bangalore. However, although they can identify sources of contamination, further inspections and actions are required to correct the problems. “Local officers must observe and enforce changes, such as re-routing traffic or stopping specific polluting activities,” he explains.
Subramanian also emphasizes the importance of expanding pollution forecasts. “Delhi uses SAFAR, an air quality dashboard maintained by the Indian Institute of Tropical Meteorologywhich provides three-day forecasts combining computational models and machine learning. However, extending the forecasting period to 10 days would give authorities more time to implement preventive measures,” he says.
Even if Delhi’s plethora of pollution control techniques can be improved and made effective – and this will take a lot of work – this does not solve the fact that air pollution is part of a much larger regional problem, as recently stated satellite photos from NASA show. A thick layer of smog now covers the entire Indo-Gangetic Plain, stretching into northern India and Pakistan. Pollution affects the entire area of the plain, the area where air flows and accumulates, moving across state and national borders, crossing political boundaries. “Efforts to address this problem must extend beyond Delhi,” says Kumar.
Sagnik Dey, a professor at the Center for Atmospheric Sciences at the Indian Institute of Technology in Delhi, says satellite data helps shift the focus from city-centric solutions to a regional approach, as reflected in India’s National Clean Air Program. “We can now track the pollution of entire swaths of air, which shows that rural areas, especially in the Indo-Gangetic Plain, are just as polluted, if not more so, due to biomass burning,” Dey says.
Subramanian suggests that satellite monitoring could go further. He would like to see it used to track methane emissions from industrial facilities to identify super emitters, as well as for ground-based remote sensing of vehicles to assess tailpipe emissions and identify damaged vehicles requiring repair or scrapping. He argues that these interventions could support broader evidence-based policy decisions.
“We cannot solve Delhi’s pollution problem by focusing solely on the city,” Dey adds. “It requires cooperation between national ministries, central and state governments, and local governments.” While data is crucial to tracking progress, Dey emphasizes that solving the problem requires action from regulators. There is a big gap between working under the National Clean Air Program and what needs to be done.
Experts believe that despite advances in pollution control technologies, Delhi’s air quality is unlikely to improve significantly over the next decade without decisive policy action. Growing energy demand, urbanization and industrial development will only raise the burden on highly polluting sectors. thermal powersteel and transport remain poorly regulated. “We already have enough science, data and solutions,” says Chanchal. “We need political will to implement them.”