As Diwali approaches, there is keen interest in understanding how the current weather conditions in Delhi will affect pollution levels, keeping in mind the worsening air quality levels due to bursting of firecrackers. Although the overall climate conditions of the city present a mixed picture, however, a detailed analysis provides some insights and predictions.
November 1, the day after Diwali, will offer more favorable weather conditions for polluting. With expected high daytime temperatures of around 35 degrees Celsius and nighttime temperatures of around 20 degrees Celsius, there are chances to help the spread of particles.
During the day, heat can increase the diffusion process, removing pollutants more efficiently than usual.
However, Thursday night and Friday morning are forecast to pose challenges for air quality management. Relatively calm wind speeds, expected to be around 8 km/h, are insufficient to rapidly disperse pollutants, possibly from fireworks, persisting until early morning. The wind speed should not increase to 16 km per hour.
In addition to temperature and wind speed, two important factors affecting pollutant dispersion are mixing depth and ventilation index.
Fortunately, Delhi's mixing depth is expected to be around 2,280 meters on Thursday. This indicates that the pollution will mix more in the atmosphere, which can help prevent the concentration of pollution near the ground.
Furthermore, the ventilation index is estimated to be 21000 m²/s, which is significantly above the favorable limit of 6000 m²/s, suggesting a strong pollutant potential.
So, while Diwali night may see a temporary accumulation of pollution, the next day promises to improve air quality in Delhi. A combination of predicted weather factors offers some respite, urging residents to be optimistic but cautious.
Delhi recorded the second hottest day in October.
On Wednesday, on the eve of Diwali, Delhi recorded its second hottest day of the month.
According to the India Meteorological Department (IMD), the national capital recorded the second highest October temperature at 36.1 degrees Celsius, 5.1 degrees above normal.
The highest temperature of the month was recorded on October 19 at 36.2 degrees Celsius.
Meanwhile, the city's 24-hour average Air Quality Index (AQI) was recorded at 307 at 4 pm on Wednesday, according to Central Pollution Control Board (CPCB) data.
Of the 40 monitoring stations, two — Anand Vihar and Mandka — were in the “severe” category with AQI levels above 400.
On Thursday, the IMD predicted fog in the morning with clear skies during the day.
The maximum and minimum temperatures are expected to be around 36 degrees Celsius and 21 degrees respectively.
(with inputs from PTI)