Noida, Ghaziabad in for long pollution haul with lower temperature, wind speed this season

Ghaziabad: The pollution levels have been high in the two cities of Noida and Ghaziabad, with the air quality index (AQI) not falling below the “very poor” category

Ghaziabad: The pollution levels have been high in the two cities of Noida and Ghaziabad, with the air quality index (AQI) not falling below the “very poor” category since October 22, except on one day in Noida on November 2. The data of the Central Pollution Control Board (CPCB) reveals that the period starting October 1 to November 6 this year has been relatively colder, with less wind speed, which has resulted in the two cities facing higher pollution levels.

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The experts of the India Meteorological Department (IMD) said that both the parameters of wind speed and direction, as well as temperature, play a vital role in determining dispersal of pollutants.

The CPCB’s data, assessed by HT, indicates that a 24 hours average temperature at four different monitoring stations in Noida was in the range of 28.9 to 31.13 degrees Celsius during October 1 to November 6 last year, while the same was 28.2 to 29.77 degrees Celsius during the same period this year.

Likewise, temperature during the same period at four monitoring stations in Ghaziabad was average of 30.12 to 31.64 degrees Celsius last year, while in the same period this year it was recorded in between 28.14 to 29.93 degrees Celsius.

“Temperature also plays a vital role in dispersal of pollutants. If the mercury is high, it heats up the earth surface and moves the air upwards. Otherwise, the pollutants remain stagnant near the ground. October this year has been relatively cooler as we also recorded the lowest temperature of 58 years at Safdarjung in Delhi this October,” said Kuldeep Srivastava, head of IMD’s regional weather forecasting centre, Delhi.

He added that apart from the mercury, the wind speed and also its direction also play vital roles in dispersal of pollutants. IMD officials on Friday had indicated that high pollution levels are likely to go till Diwali.

“If the wind speed is below 5kmph then dispersal of pollutants becomes difficult. They disperse better in a wind speed range of 10-12kmph, while wind speed ranging 15-18kmph will clear more of the trapped pollutants. If the wind direction is north-westerly, they will bring in effects of stubble-burning from states like Punjab and Haryana, while easterlies will lower the effect as they come from eastern Uttar Pradesh,” he added.

According to official statistics of the Consortium for Research on Agro-ecosystem Monitoring and Modelling from Space (Creams) Laboratory, the instances of stubble burning in Punjab, Haryana and UP, combined, have risen to 55,287 from October 1 to November 5 this year, as compared to 42,437 and 40,140 during the same period in 2019 and 2018, respectively.

The CPCB data recorded at four monitoring stations of Noida from October 1 to November 6 last year indicates average wind speed was in the range of 2.88 to 5.07kmph, while it was recorded in lower range of 2.12 to 4.7kmph during the same period this year.

For Ghaziabad, the average range during the same period last year was 4.28 to 6.9kmph, while during the same period this year the average range was 1.4 to 6.08 kmph at the four monitoring stations.

“It is due to the combined effect of lower temperatures and relatively low wind speed that we have seen an early spike in pollution levels this year. The contribution of stubble-burning and local pollutants has also impacted,” said Utsav Sharma, regional officer of UP Pollution Control Board (UPPCB).

“Last year, Noida and Ghaziabad started to witness high pollution levels at least three days before Diwali (Diwali was on October 27 last year) and the two cities reached a peak on November 1 and then there was gradual decline. However, this year, we are witnessing a peak since October 22 and with present conditions, it seems that it is likely to continue up to Diwali and a couple of days after, due to any effect of bursting crackers,” he added.

City-based environmentalist Akash Vashishtha said that a longer period of high pollution levels should attract strict enforcement.

“The pollution levels have already started rising and it is likely that such conditions will prevail till Diwali and a couple of days thereafter,” he added.