Ghaziabad, Noida record better AQI due to ‘insufficient data’
Ghaziabad: The twin cities of Ghaziabad and Noida that were reeling under “very poor” air quality on Monday, moved to “poor” category of air quality index (AQI) on Tuesday due to unavailability of readings from two air-quality monitoring stations — Loni in Ghaziabad and Sector 62 in Noida.
These cities, running high on pollution levels post-Diwali, on Monday recorded AQI levels of 314 and 319 respectively, under the “very poor” category with 24-hour average AQI readings of all four stations each in two cities. On Tuesday, the daily AQI bulletin released by the Central Pollution Control Board (CPCB) on Tuesday stated AQI levels of 268 and 265 for Ghaziabad and Noida respectively, and Greater Noida at 291 under the “poor” category. Readings for Ghaziabad and Noida were computed from only three stations each.
The Ghaziabad district has four monitoring stations at Indirapuram, Loni, Sanjay Nagar and Vasundhara. Of these, Loni had been witnessing high pollution levels and contributing majorly to the city’s AQI levels of 377, 383 and 350 (past 24-hours average at 4pm) on November 2, 3 and 4, respectively, according to CPCB. Loni’s figures did not add up in the AQI figures released on Tuesday, officials said.
“We do not know about Loni station, but it could have been due to some malfunction or technical snag that its readings were not available. Otherwise, the activities under the Graded response action plan are underway to help improve polluted conditions,” said Vikas Mishra, regional officer, Uttar Pradesh pollution control board (UPPCB).
The CPCB classifies AQI between 0-50 as “good”, between 51 and 100 as “satisfactory”, between 101 and 200 as “moderate”, between 201 and 300 as “poor”, between 301 and 400 as “very poor”, and over 400 as “severe”.
In Noida, the station at Sector 62 recorded high average AQI levels of 349, 323 and 349 November 2, 3 and 4, respectively.
“The Sector 62 station had been running high on pollution levels and its readings were not available on Tuesday due to some issue. This monitoring station is managed by India Meteorological Department. There must be some snag or technical issue in getting the reading. So, reading of only three stations was averaged. However, it was also observed that Noida’s AQI also started to lower down since Tuesday afternoon,” said Utsav Sharma, regional officer of UPPCB, Noida.
Environmentalists said that the cities in the NCR require more monitoring stations at different locations to get comprehensive picture of pollution levels.
“The overall AQI of the city is provided only on the basis of reading of four stations and this is not comprehensive. If there are more stations, the overall scenario may change due to more readings available from different areas,” said Sushil Raghav, a Ghaziabad-based environmentalist.
Meanwhile, the AQI for nearby Delhi and Gurugram stood at 373, 298, respectively, on Tuesday.
On the other hand, the air quality early warning system for Delhi said in a forecast on Tuesday, that the lower ventilation index “with average wind speed less than 10 kmph is unfavourable for dispersion of pollutants. Meteorological conditions are likely to be extremely unfavourable for dispersion of pollutants.”
It also predicted wind speed of 4-8kmph over Delhi on November 6 and 7. The forecast also indicated that the contribution of stubble burning to Delhi’s PM2.5 concentration rose from 19.72% on Sunday to 23.36% on Monday.
