On Monday, the level of pollution slightly decreases in the national capital, moves from “severe” to “very poor” category, with an increase in the speed of the wind that reduced the noxious haze that obscured skies for over a week in Delhi.
A day after the level of pollution peaked to a three-year-high (494), the city’s air quality index at 4:00 PM, read 407. It dipped further at 8:30 PM the AQI stood at 370, which comes under the category of “very poor”.
The relief was reported as the number of vehicles on the roads came down considerably with the AAP Government rolling out its car rationing scheme.
Central Pollution Control Board’s former Air Lab Chief Dipankar Saha has said that “though there is a significant, visible change in pollution levels, the national capital’s air quality index remained in the “severe” category till 4 pm. This is because the AQI reading at any given time is an average of AQIs recorded in the previous 24 hours.”
With winds in the national capital gusting up to 20 km per hour dissolving pollutant faster, the visibility level has improved to 2000-meters.
IMD (India Meteorological Department) has said that Cyclone Maha and a western disturbance will cause pouring in several parts of the northern plains, covering Punjab, Rajasthan, Delhi-NCR, Western Uttar Pradesh, and Haryana, which is expected to improve the situation.
Weather Department Experts has said that a significant increase in wind speed disturbed the pollutants faster. Cloud covering over the national capital and its adjacent areas also dissolute, reveals that the Sun has caused the air close to the ground to rise up and flush out pollutants.
The Government of Delhi has shared information that displays a drastic improvement in PM10 and PM2.5 level in the city.
As per the data, the level of PM2.5 – tiny particular matter less than 2.5 microns in diameter that can enter the lungs and the bloodstream, reduced from 562 micrograms per cubic meter at 6:00 AM to 94 micrograms per cubic meter at 6:00 PM.
PM10 level reduced at 6:00 AM from 710 micrograms per cubic meter to 216 micrograms per cubic meter at 6:00 PM.
Veteran Scientist Kuldeep Srivastava was quoted saying, “The two main reasons for the improvement in air quality are increased wind speed and no cloud cover. The situation will improve on Tuesday with wind speed increases further.”
Skymet Weather’s Mahesh Palawat has said that rainfall is expected in Delhi and adjacent areas on the following days under the influence of Cyclone Maha.
Mr. Palawat continued, “A western disturbance will also increase wind speed…Strong easterly winds due to Cyclone Bulbul will reduce the impact of smoke from stubble burning in (Haryana and Punjab).”
The Ministry of Earth Sciences’ Air Quality Monitor, SAFAR has said that “high surface and boundary layer winds are expected on Tuesday also. A fresh western disturbance, scattered rainfall, and change in wind direction are likely to positively influence the AQI in the region.”
In the National Capital Region (NCR), Ghaziabad (392), Noida (391),) and Greater Noida (392), Faridabad (378), Gurgaon (355) also recorded improvement in air quality.
An AQI between (0-50) is considered “good”, (51-100) as “’satisfactory”’, (101-200) as “moderate”, (201-300) as “poor”, (301-400) as “’very poor”, and (401-500) as “severe”, above 500 falls in the “severe-plus” category.