Delhi's Air Pollution Crisis: Beyond Symbolic Measures

As Delhi's skyline turns into a toxic haze with air quality indices breaching hazardous levels, the pressure to act swiftly intensifies. The latest response, a pilot cloud seeding experiment, aimed to induce rainfall that can temporarily wash pollutants from the atmosphere. However, experts maintain that such an intervention cannot truly address Delhi's deeply entrenched complex air pollution problem.

Key Takeaways:

• Cloud seeding, a weather modification technique, involves dispersing substances into clouds to encourage rainfall, but its use to reduce air pollution remains rare and scientifically inconclusive.
• Rainfall can temporarily wash away suspended particulates, but its effects are short-lived and depend heavily on suitable clouds, humidity, and wind conditions.
• Delhi's pollution pattern is well understood, with anthropogenic and meteorological factors contributing to its seasonal behaviour, including large-scale agricultural residue burning in Punjab and Haryana.
• Studies by IIT Delhi, TERI, and the System of Air Quality and Weather Forecasting and Research (SAFAR) have consistently identified the sources and seasonal behaviour of Delhi's pollution.
• Policy responses often take the form of short-term or symbolic measures, neglecting sustained interventions and known sources and solutions.
• Even if the cloud seeding experiment had succeeded, its effect would have been confined to a small area, and for a short duration, unable to solve the regional crisis of air pollution.
• Delhi has experimented with various emergency measures, such as smog towers, odd-even vehicle schemes, and artificial rain, but these divert attention and resources from comprehensive, long-term action.
• Air pollution is a systemic issue tied to energy use, transport systems, waste management, and agricultural practices, requiring effective implementation of existing plans and coordinated governance.

Statistics:

• Air quality indices in Delhi have breached hazardous levels repeatedly, with a high of 527 AQI in November 2019 (SAFAR).
• The entrance of stubble burning emissions from Punjab and Haryana contributes to Delhi's pollution, with an estimated 30% of the pollutants coming from outside Delhi (IIT Delhi).
• Delhi's pollution is a regional phenomenon influenced by emissions from across the National Capital Region (NCR) and neighboring states, with localised rain only addressing a small area (SAFAR).
• Low-cost air quality sensors, AI-driven emissions monitoring, and satellite-based forecasting can support efforts to address air pollution, but they must be embedded within a long-term governance framework.

Sources:

• IIT Delhi
• TERI
• System of Air Quality and Weather Forecasting and Research (SAFAR)
• Commission for Air Quality Management (CAQM)
• iFOREST