Delhi’s air quality saw a significant improvement on Saturday morning, transitioning from the ‘poor’ category to ‘moderate,’ with an Air Quality Index (AQI) reading of 179. This welcome change followed continuous rainfall over the past few days, which helped clear the air of pollutants and brought relief to the city’s residents.
The improvement marks a shift from the ‘severe’ levels earlier this week, as pollution curbs under the Graded Response Action Plan (GRAP) Stage III were lifted on Friday. The city also recorded a morning temperature of 13.8°C, with an expected low of 12°C later in the day.
The Journey from Severe to Moderate Air Quality
Delhi has long struggled with hazardous air pollution, particularly during the winter months. Earlier in the week, the city’s AQI had risen to ‘severe’ levels due to stagnant weather conditions and increased emissions from vehicles, industries, and stubble burning in neighboring states. However, the rainfall over the past two days played a crucial role in dispersing particulate matter, leading to a marked improvement in air quality.
Impact of Rainfall on Pollution Levels
- Washout Effect:
The rainfall helped wash away suspended particulate matter (PM2.5 and PM10) from the atmosphere, significantly reducing pollution levels. - Improved Visibility:
The rains not only improved air quality but also enhanced visibility, making it easier for commuters to navigate the city. - Drop in Temperature:
The Indian Meteorological Department (IMD) recorded a temperature of 13.8°C at 5:30 am on Saturday, with a low of 12°C expected. The cooler temperatures, combined with the rainfall, contributed to better air quality.
Revocation of GRAP Stage III Measures
The Graded Response Action Plan (GRAP) is a set of emergency measures designed to combat air pollution in Delhi-NCR based on AQI levels. Under Stage III, restrictions included a halt on construction activities and enhanced monitoring of industrial emissions.
With the improvement in air quality, authorities decided to lift these curbs, allowing construction and other activities to resume. However, officials have urged residents and industries to continue adopting environmentally friendly practices to sustain the progress.
Why Does Delhi Face Severe Pollution in Winter?
Delhi’s air pollution woes are exacerbated during winter due to several factors:
- Stubble Burning: Farmers in neighboring states like Punjab and Haryana burn crop residues, releasing large amounts of smoke into the atmosphere.
- Low Wind Speeds: Winter weather often brings calm winds, preventing pollutants from dispersing.
- Temperature Inversions: Cold air near the ground traps pollutants, leading to higher concentrations of particulate matter.
- Increased Emissions: The use of heaters, generators, and vehicles contributes to higher emissions during winter months.
Efforts to Combat Pollution
- Policy Measures:
The Delhi government has implemented several measures, including the Odd-Even vehicle scheme, bans on firecrackers, and the use of anti-smog guns in construction zones. - Public Awareness:
Campaigns encouraging the use of public transport, carpooling, and reducing the use of private vehicles have been promoted. - Technological Interventions:
The introduction of smog towers and plans to adopt cleaner fuels are part of the long-term strategy to address pollution.
The Role of GRAP
The Graded Response Action Plan is an adaptive framework that enables authorities to take targeted actions based on real-time air quality data. The stages range from I to IV, with Stage III focusing on curbs like halting construction, restricting industrial emissions, and encouraging remote work.
With AQI levels now in the ‘moderate’ category, the lifting of GRAP Stage III measures reflects the city’s improving air quality but also underscores the need for sustained efforts to maintain this progress.
Looking Forward
While the rains have brought temporary relief, experts caution that air quality can deteriorate rapidly without consistent interventions. The improvement offers a glimpse of what can be achieved with a combination of favorable weather conditions and proactive policies.
Delhi’s battle against air pollution is far from over. As winter progresses, residents and authorities must remain vigilant, ensuring that recent gains in air quality are not lost. The challenge lies in balancing developmental activities with environmental sustainability, a task that requires cooperation from all stakeholders.
For now, Delhiites can breathe a little easier, enjoying cleaner air and the hope that a concerted effort will lead to a healthier future for the city.