Air quality continues to remain in the 'severe' category in Delhi and surrounding cities on Wednesday morning with pollution levels expected to enter the "severe-plus" or "emergency" category.
According to the Central Pollution Control Bureau (CPCB), air quality index (AQI) in Delhi's Lodhi Road read 500 at 6 am and 472 in Noida. On Tuesday, Delhi's AQI stood at 425 at 4 pm and 437 at 9 pm. It was 360 at 4 pm on Monday.
The levels of PM 2.5 -- tiny particulate matter less than 2.5 microns in diameter that can enter deep into the lungs and even the bloodstream -- shot up to 337 micrograms per cubic metre, breaching its emergency threshold of 300, by 9 pm in Delhi-NCR.
The levels of PM10 increased to 484 micrograms per cubic metre, nearly five times the safe limit of 100 micrograms per cubic metre. Most of the 37 air quality monitoring stations across Delhi recorded air quality in the severe category.
An AQI between 201 and 300 is considered 'poor', 301-400 'very poor' and 401-500 'severe'. An AQI above 500 falls in the 'severe plus' category.
WHY THE DIP AGAIN
The noxious haze returned to Delhi and its suburbs on Tuesday with raging stubble fires in neighbouring states and fall in the temperature.
Experts said the spike in pollution levels can be attributed to a significant decline in wind speed. Incidents of stubble burning in Haryana and Punjab have increased and northwesterly winds have been bringing more farm fire plumes to the Delhi-NCR region, they said. The condition may slightly improve by November 15, experts added.
According to SAFAR, the share of stubble-burning accounted for 25 per cent of Delhi's pollution on Tuesday, up from 18 per cent on Monday.
A dip in wind speed and temperature makes the air cold and denser, leading to accumulation of pollutants, said Kuldeep Srivastava, head of the India Meteorological Department's regional weather forecasting centre.
WHAT IS GOVT DOING AS POLLUTION LEVEL INCREASES
Also Read: Delhi pollution: Air quality deteriorates again
Last week, the apex court had pulled up the Centre and state governments for their inability to curb stubble-burning in Punjab and Haryana and bring air pollution in Delhi under control. It had asked the governments if they feel ashamed that people are no longer safe even in their houses.
The top court had also ordered that all farmers be given a Rs 100 per quintal incentive to prevent them from setting their fields on fire in preparation for the next crop and provide them free machines to get rid of the agriculture residue.
The period between October 15 and November 15 is considered critical as a maximum number of stubble-burning incidents take place in this span in Punjab and adjoining states, which is one of the main reasons for the alarming spike in pollution in Delhi-NCR.