Pollution, winter, and Delhi’s annual tryst with bad air
Every year, agencies along with the state and Union environment ministers suggest air quality may not deteriorate like the previous years because of several new measures. But invariably, the onset of winter brings a massive public health challenge
New Delhi: In the middle of September, people in Delhi were sharing pictures of azure blue skies, while exclaiming how the clean air in the Capital made a difference to their lives.
Gradually, air quality started declining, hitting “poor” levels (air quality index of 201 to 300) on October 16 when a grey sky hung over the Capital. After two episodes of unseasonal thunderstorms and rain came to Delhi’s rescue, air quality monitoring agencies have warned of a downward spiral this week onwards.
Every year, agencies along with the state and Union environment ministers suggest air quality may not deteriorate like the previous years because of several new measures that have been put in place. But invariably, the onset of winter brings a massive public health challenge, leading to increased hospitalisations with complications of chronic pulmonary obstructive disease, strokes, asthma, cardiac issues and so on.
“As doctors, we see the impacts of pollution on people first-hand, especially on the more vulnerable sections like senior citizens and children. In many health-related issues, you might not see an immediate impact of pollution exposure, but in more chronic cases, pollution does play a role in deteriorating a patient’s condition,” said Arvind Kumar, founder of Lung Care Foundation and chairperson of the Institute of Chest Surgery, Chest Onco Surgery and Lung Transplantation.
This is significant because the World Health Organization (WHO) tightened its air quality guidelines last month bringing down the annual PM 2.5 (respirable pollution particles) guideline from 10 micrograms per cubic metres to 5 micrograms per cubic metres, and the 24-hour PM 2.5 guideline from 25 micrograms per cubic metres (µg/m³) to 15 micrograms per cubic metres based on the latest evidence of health impacts from air pollution.
In comparison, India’s thresholds are much higher. According to the 2009 National Ambient Air Quality Standards still in force, the acceptable PM2.5 exposure limit over 24 hours is 60µg/m³ (four times the new WHO limit), and for exposure over a year-long period, 40µg/m³ (eight times the revised WHO threshold).
What happens in the winter?
While various factors come together to deteriorate Delhi’s air quality in the winter — including a range of local and external factors — the weather plays a dominant role in keeping fine, respirable pollution particles (PM 2.) closer to the surface, not allowing them to disperse as easily as they would during any other time of the year.
When the monsoon starts retreating from northwest India around October, wind direction changes from easterly to north-westerly. During monsoons, the winds, travelling from over the Bay of Bengal, carry moisture and bring rains to northwest India washing away accumulated pollutants frequently. But after monsoon withdrawal, wind speed is low and north-westerly winds are dry.
October also coincides with the harvest season in agrarian states such as Haryana and Punjab, from where winds blow into Delhi. Following the harvest, farmers burn paddy stubble which leads to the release of severe particulate pollution over Haryana, Punjab, Uttar Pradesh, and Delhi.
This year, Punjab reported 4,006 and Haryana reported 1,835 stubble fires from September 21 to October 14, according to an analysis by the Central Pollution Control Board. On October 16 alone, there were 429 fire points in Punjab, and 176 over Haryana.
“Along with the change in wind direction, the rise in pollution levels can also be attributed to a fall in temperatures. As temperature dips, the inversion height — a layer of the atmosphere beyond which pollutants cannot disperse — is lowered. Here is how to understand it: Visualise the pollution particles in the atmosphere as students in a classroom. While the same number of students can move around and play freely in a larger classroom, as the size of the classroom shrinks, they look more packed and have difficulty in moving freely,” said RK Jenamani, senior scientist, India Meteorological Department (IMD).
The current interventions
The Union environment ministry is trying a basket of measures to keep the number of stubble fires low this time.
Environment minister, Bhupender Yadav, said in September, during a press briefing on his meeting with environment ministers of Haryana, Punjab, Rajasthan, UP, and Delhi, that a bioenzyme developed by the Indian Agricultural Research Institute (IARI), Pusa which helps decompose stubble in around 30 to 35 days is being used widely. The decomposer capsules will also be used over a million ha in Uttar Pradesh; 100,000 ha in Haryana; 1680 ha in Delhi and 3000 ha in Punjab. The agriculture ministry had, under the Promotion of Agricultural Mechanization for In-Situ Management of Crop Residue in the State of Punjab, Haryana, Uttar Pradesh and the National Capital Territory (NCT) of Delhi, allotted ₹700 crore for five years until 2020. Around 156,000 machines have been distributed, there are over 12,000 machine hiring centres in Punjab alone which will also be utilised.
Yadav said that one of the important interventions this year will be of using stubble as biofuel. The National Thermal Power Corporation has floated a tender for 20 million tonnes of stubble for 4 years, according to Yadav. There are also projects in Kutch and parts of Rajasthan to procure paddy stubble for fodder which will be added to other forms of fodder to make it suitable for cattle.
A senior environment ministry official had said the area under Pusa 44 — which matures late and leaves a lot of stubble — has reduced this year. Punjab also ran a campaign called “Mera Pani Meri Virasat” in which area under paddy has reduced marginally. The overall area under Basmati has increased, which normally doesn’t cause trouble with stubble because it decomposes easily.
A senior scientist of the Punjab Agricultural University said that while the number of stubble fires in Punjab this year has been considerably lower compared to the previous years, it will be difficult to assess if these are a result of government interventions or if these fires are merely delayed because of unique weather conditions that north India has witnessed this time.
“The usual trend is that from mid-October fires start peaking and by end of October and the first week of November the numbers peak to 3,000-4,000 a day. But currently, we are only reporting 300-400 fires a day. However, it is still too early to establish any trend because this could be a temporary situation because we saw a late monsoon withdrawal in the region this time and even in October there were episodes of heavy rain and hail in the state,” the scientist explained.
The emissions and the commission
Hostile weather and stubble fires are added to the city’s local pollution sources, which include construction and road dust, vehicular pollution, and open burning of waste.
Over the last few years, Delhi has seen the formation and dismantling of several pollution monitoring and overseeing bodies tasked with controlling this annual air emergency. Little has changed in terms of action on-ground. And this year might not be too different.
The Commission for Air Quality in the National Capital Region and Adjoining Areas Act was notified in August. It replaced the Supreme Court-mandated Environment Pollution Control Authority in overseeing air pollution-related issues in Delhi. The newly constituted commission has sweeping powers in controlling air pollution in Delhi-NCR.
Any non-compliance or contravention of any provisions of the act, rules made thereunder, or any order or direction issued by the commission is a punishable offence with imprisonment of up to five years or with a fine which may extend up to ₹1 crore, or both. The commission has exclusive jurisdiction in matters covered by the act. No other body or authority or committee or individual will have any power or jurisdiction in that matter.
In addition, the Delhi government this year has announced the formation of a dedicated winter action plan to tackle various aspects of winter pollution in the city, and also pin accountability on agencies. This plan promises to focus on 10 primary sources, which tend to flare up during the pollution season and tackle it.
While submitting its individual action plan to the Delhi government, the three municipal agencies (north, south, and east corporations) plan to curb pollution from waste burning and dust, focusing on intensive patrolling, increased mechanical sweeping, targeted operation of GPS-monitored water sprinkling tankers, and a new portal being developed with the help of the Delhi Pollution Control Committee (DPCC) to monitor large construction sites.
This year, agencies will also have to focus largely on construction sites. Because of the Covid-19 pandemic, several construction projects in the city are racing to meet their deadline, which means that many pockets are lying dug-up with dust flying around and construction material slipping out of tin sheets, which in most sites are merely a boundary for show.
Currently, in Delhi, there are at least six major ongoing construction projects. This includes the Central Vista, the underpass at Pragati Maidan, the Ashram underpass, the Barapullah extension, the Delhi Metro Phase-IV corridors, and the Regional Rapid Transit System (RRTS).
“The idea behind formulating a dedicated winter action plan for Delhi is to identify the problem and fix responsibility on agencies. As we go into the season, we will constantly keep monitoring the pollution sources and identify agencies that need to act on them. This will lead to systematically handling all the sources,” said a senior official of the DPCC.
Environment experts, however, said that Delhi has, over the last few years, seen several “action plans”, but results can only be seen when agencies act on those plans. Many also said that Delhi already has a holistic action plan in place — the Graded Response Action Plan (GRAP) —which details what each agency needs to do.
“It is not like Delhi has been moving aimlessly in managing winter pollution in the last few years. There is a detailed GRAP in place, which tells each agency exactly what to do when pollution reaches a certain level. It is good that the government is taking the matter seriously and is forming an action plan, but the true test comes to how well these plans are implemented,” said Anumita Roychowdhury, executive director (research and advocacy), Centre for Science and Environment.
Karthik Ganesan, fellow and director (research coordination) at the Council on Energy, Environment and Water, said that while there have been efforts year after year to manage the pollution crisis in the Capital, source-specific action is needed.
“There is an increasing level of effort each year and the administrative machinery is on ‘high alert’ to the impending air quality deterioration. However, the efforts are required on a number of fronts ranging from addressing issues within Delhi waste burning, high load from private vehicle use, poor service levels of buses which are the most used mode of transport, unabated emissions from large construction sites and none of these have been addressed in a concerted manner,” Ganesan said.
He added, “A well-functioning app to report transgressions helps fire-fighting, but the sources outside the boundary of Delhi and indeed entrenched sources within need to be addressed year-round and not just as we enter the autumn season.”