Air quality drops but may improve slightly todayUpdated: Nov 27, 2019 00:00 IST
Contrary to the forecast, air quality in the national capital plunged marginally on Tuesday, though remaining in the ‘poor’ zone. Scientists at the India Meteorological Department (IMD), however, said air quality may improve slightly on Wednesday on account of an expected drizzle and gusty winds.
While light rain was the forecast for Tuesday that would improve the air quality, only traces were recorded in the early hours. According to the Central Pollution Control Board (CPCB), air quality will remain in the ‘poor’ zone and may deteriorate slightly on November 28.
The overall average air quality index (AQI), as calculated by the CPCB’s 4 pm bulletin on Tuesday was 270, as against 252 on Monday.
At 8pm, many of the monitoring stations including Anand Vihar, Dwarka, Najafgarh, Vivek Vihar and Wazirpur, among others recorded ‘very poor’ air quality while IHBAS Dilshad Garden was the only one to have an AQ I of 181 in the ‘moderate’ zone.
The average PM 2.5 (fine particulate matter with diameter less than 2.5 micrometres) levels at 8 pm was 118 ug/m3, nearly two times the prescribed safe limit of 60ug/m3.
According to meteorologists, “The Western Disturbance was not strong enough to induce rainfall in Delhi. However, rain in the neighbouring regions such as Haryana and parts of Punjab is having a good impact on Delhi’s air. Also, the wind direction has now become southeasterly. There might be some deterioration in air quality on November 28 with wind direction again changing to northwesterly,” said Kuldeep Srivastava, head, IMD’s regional weather forecasting centre.
The north westerly winds usually travelling from Punjab and Haryana bring in the pollutants. However, officials in Punjab and Haryana had said on Monday that farm fires would end soon since paddy harvesting season is going to be over.
The average wind speed was 8-10 kmph on Tuesday and is expected to remain similar over the next few days, he said. The minimum temperature settled at 16.2 degrees C, five notches above normal while maximum settled at 27.9 degrees C, two notches above normal.
A drop in temperature is expected on November 30 when it is expected to be around 12 degrees C and further to 10 degrees C on December 1, said IMD officials.
The System of Air Quality and Weather Forecasting and Research (SAFAR), ministry of earth science’s weather and air quality monitoring wing, data also shows that on Tuesday, the share of crop stubble burning in the neighbouring states of Punjab and Haryana contributed to 4% to overall pollution in Delhi. On Wednesday, it will go down to 2%, the SAFAR forecast said.