Behind Delhi’s polluted air: Early stubble fires, weather

The cause for Delhi’s air high quality to worsen over the previous week is antagonistic meteorological circumstances and the early begin of stubble burning, primarily in Punjab, officers from the Central Pollution Control Board (CPCB) mentioned on Friday.

The silver lining? The peak of stubble burning might not coincide with the worst meteorological circumstances .

Last yr, in September and October (until October 14), there have been seven wet days that introduced round 121 mm rain. This yr, there have been solely three wet days in the identical interval, and so they have introduced solely 21 mm rain. The common air flow index on this interval has been 1389 sq. metres/s, with a low of 636 sq m/s. The air flow index is a operate of the blending top and the wind pace and defines the flexibility of the environment to disperse contaminants. A air flow index under 2350 sq metres/second is taken into account poor. The mixing top is the peak at which the pollutant mixes within the air.

On Friday, the contribution of stubble burning to Delhi’s PM 2.5 (particulate matter 2.5 microns or smaller in width) focus was 11% based on CPCB, maybe a operate of the exceptionally excessive air flow index of 8800 sq m/s.

At its peak, stubble burning accounts for nearly half of Delhi’s air pollution. Last yr, this was 44% on October 31.

Also Read: CPCB divides Delhi into four zones to focus higher on anti-pollution conflict

Prashant Gargava, member secretary, CPCB mentioned that as a result of the harvest of the kharif (monsoon) crop and stubble burning began sooner than regular this yr, the peak of the fires might not coincide with essentially the most antagonistic meteorological circumstances in Delhi.

Indeed, based on the India Meteorological Department, the harvest season until October 15 this yr has seen 3515 fires in Punjab and Haryana, nearly 3 times the 1217 in the identical interval final yr, and 5 occasions the 773 fires recorded in 2018.

“This year because stubble fires have started relatively early we are hoping that the peak contribution from fires reduces by the time minimum temperature starts falling significantly and before Diwali,” mentioned Gargava. Diwali will probably be celebrated on November 14 this yr. Diwali was celebrated on October 27 final yr.

Interestingly, contribution from stubble fires might also be decrease this yr this yr as a result of the space below non-Basmati paddy (which leaves stubble that must be disposed) has decreased in each Haryana and Punjab this yr after a really very long time based on officers. In Punjab, the realm below non-Basmati paddy has decreased from 2.291 million hectares (ha) to 2.076 million ha this yr; in Haryana the realm has decreased from 648000 ha to solely 427000 ha, Gargava mentioned.

“This year around 400000 ha non-Basmati area has gone to other crops like cotton and maize according to our assessment. Out of 2.076 million ha area under non-Basmati in Punjab only 482000 ha is under under long duration variety Pusa 44 this year. This means that most farmers grew short duration paddy variety and had more time to dispose stubble. We are hopeful that stubble fires will be lower this year. Our concerns are that there should be efficient use of the straw management machines that have been distributed,” ,” mentioned Trilochan Mohapatra, director basic, Indian Council of Agricultural Research.

Also Read: Supreme Court constitutes one-member committee to observe farm fires in Punjab, Haryana and Uttar Pradesh inflicting air air pollution in Delhi-NCR

To be certain, information on the variety of straw administration machines distributed this yr, in comparison with final yr, and the usage of these machines isn’t accessible. The enhance in fires to information would appear to counsel that sufficient of those machines aren’t getting used.

Mohapatra added that “another apprehension is that because of attention of farmers going to farm bill agitation, they may be resorting to burning stubble”.

Elaborating on CPCB’s plans for the winter, Gargava mentioned discipline inspections will probably be carried out from October 15 to February 28—a interval of practically 5 months. Industries and building companies must present an enterprise for adhering to prescribed environmental norms equivalent to preserving mud down, protecting the development house and so on. Delhi Pollution Control Committee can even deploy inspection groups.

Gargava mentioned that there’s round 20% discount in annual PM 2.5 concentrations from 2016 to 2019 and 25% discount in PM 10 concentrations.