Light rain, wind bring down pollution level in Delhi, still in 'severe' category

Pollution levels in Delhi and neighbouring cities dropped marginally on Saturday with slight increase in wind speed and light rains, a day after the region recorded its worst air quality forcing authorities to shut schools, ban all construction activities and declare a public health emergency.

Light scattered rainfall due to a western disturbance slightly brought down the city's overall air quality index (AQI) to 402 at 8 pm from 407 at 10 am. It was 484 at 4 pm on Friday, according to official data.

However, 20 out of 37 monitoring stations recorded AQI in the 'severe' category (401-500). Vivek Vihar was the most polluted at 450 followed by Anand Vihar and ITO, both at 448.

In the National Capital Region (NCR), Ghaziabad, Noida and Greater Noida recorded AQIs of 455, 432 and 429, respectively, at 8 pm on Saturday. On Friday, Ghaziabad and Greater Noida had an AQI of 496 at 4 pm, the Central Pollution Control Board (CPCB) said.

An AQI between 0-50 is considered "good", 51-100 "satisfactory", 101-200 "moderate", 201-300 "poor", 301-400 "very poor", and 401-500 "severe". Above 500 is "severe-plus or emergency" category.

In a crackdown on violators, authorities arrested 34 people including a director and three engineers, from sites of five real estate groups in Noida and Greater Noida for carrying out construction activities despite the ban.

The South Delhi Municipal Corporation issued challans of Rs 5 lakh to each of the four companies involved in the ongoing development work at Pragati Maidan for violating the National Green Tribunal order pertaining to construction work.

Over 22,000 cases of stubble burning had been witnessed in Punjab and more than 4,200 incidents in Haryana in the recent days, officials said.

The share of stubble burning in Delhi's pollution, however, reduced from 44 per cent on Friday, the season's highest, to 17 per cent on Saturday, according to government air quality monitor SAFAR.

Weather experts said there is a significant improvement in wind speed and it will increase gradually. Winds gusting up to 20-25 kilometres per hour are likely in the region from Sunday to Tuesday, they said.

Scattered rainfall in Punjab, Haryana, Rajasthan and Delhi is likely on November 7 and November 8 under the influence of Cyclone Maha and a fresh western disturbance, the weather office said.

This rainfall, however light, will be significant in terms of reducing the effect of stubble burning, and will wash away pollutants, they said.

On Friday, the Supreme Court-mandated Environment Pollution (Prevention and Control) Authority declared the public health emergency, following which the Delhi government decided to shut all schools. The EPCA also banned construction activities in Delhi-NCR till November 5.

The AQI entered the 'severe plus' or 'emergency' category late Thursday night in Delhi, the first time since January this year.

Amid a blame game over failure to check toxic haze that has enveloped the national capital and neighbouring areas, the governments of Delhi, Punjab and Haryana on Saturday called for urgent intervention by the Centre to develop and implement a joint plan with the states to address the "serious" situation.

Delhi's Deputy Chief Minister Manish Sisodia accused Union Environment Minister Prakash Javadekar of postponing meetings with state environment ministers thrice, on September 12, October 17 and on October 19, saying either he has no time or does not consider treating the national capital's poor air quality a priority.

Kejriwal, meanwhile, wrote to Javadekar saying air pollution "is not a Delhi specific issue, it is a North India issue and therefore, requires a North India solution under the "chairmanship" of the Union Minister.

Haryana Chief Minister Manohar Lal Khattar also wrote to Javadekar requesting him to convene a meeting of chief ministers of Delhi and neighbouring states to prepare a joint strategy to address the problem of severe pollution in the National Capital Region.

In a letter to Prime Minister Narendra Modi, Punjab Chief Minister Amarinder Singh too stressed on the need for the Centre's urgent intervention, underscoring that his state was not oblivious to the misery of people in the national capital, "whatever many around the country might have been led to believe.