Air Pollution in Delhi and Mumbai- Explained Pointwise

Introduction

Air Pollution in Delhi and Mumbai has again hit the national headlines. Delhi’s air quality has breached the 400 AQI mark to hit the ‘severe’ category and plummeted to reach 575. Before Delhi, Mumbai in October witnessed  ‘severe’ air quality. 

According to the recently published ‘Respirer Reports’ by Respirer Living Sciences, PM 2.5 levels in both Delhi and Mumbai has been increasing in the last five years.

Delhi’s air pollution worsening for the past two years	Mumbai’s air quality steadily deteriorates from 2019 to 2023

What is air Pollution and how is it measured in India?

Air Pollution- Air pollution is the introduction of chemicals, particulates or biological materials into the atmosphere that cause discomfort, disease or death to humans.

Measurement of Air Pollution In India

In India, air pollution is measured according to the National Air Quality Index developed by Central Pollution Control Board (CPCB) in 2014.

The measurement of air quality in the NAQI framework is based on eight pollutants , namely-
Particulate Matter (PM10), Particulate Matter (PM2.5), Nitrogen Dioxide (NO2), Sulphur Dioxide (SO2), Carbon Monoxide (CO), Ozone (O3), Ammonia (NH3) and Lead (Pb).

What are the reasons for the rise in air pollution in Delhi and Mumbai?

Reasons for the increase in air pollution in Delhi

(1) Stubble Burning- Stubble burning in Punjab, Rajasthan and Haryana emits large amounts of toxic pollutants in the atmosphere. These pollutants contain harmful gases like methane (CH4), carbon monoxide (CO), volatile organic compounds (VOC) and carcinogenic polycyclic aromatic hydrocarbons.

(2) Reduced Wind Speed- Low-speed winds in winters are unable to disperse these pollutants effectively. Further, Delhi lies in a landlocked region and does not have the geographical advantage of sea breeze to disperse the suspended pollutants.

(3) Effect of Northwesterly winds- After the withdrawal of monsoons, the predominant direction of winds in northern India is northwesterly. These northwesterly winds bring the dust from the gulf region, northern Pakistan and Afghanistan.

(4) Dip in Temperatures lowers the inversion height- With the decrease in temperature, inversion height lowers down, leading to concentration of pollutants in the lower atmosphere. (Inversion height is the layer beyond which pollutants cannot disperse into the upper layer of the atmosphere).

(5) Vehicular Pollution- Delhi has one of the highest number of registered private vehicles in India. Official emissions inventories of 2018 show that vehicles emit about 40 per cent of the particulate load in the city of Delhi.

(6) Construction Activities and Open Waste Burning- Pollution due to landfill burning and construction debris enhances the pollution levels in the Delhi NCR region.

(7) Firecrackers- Firecrackers burning during Diwali further adds to the increase in air pollution levels.

Reasons for the Increase in air Pollution in Mumbai

(1) Delay in the sea wind reversal pattern- The sea wind reversal pattern has been delayed. Hence the pollutants in the atmosphere could not be taken away to the sea. (Sea wind reversal is the alternating movement of winds from land to sea and sea to land). 

(2) Increased temperature in Mumbai- Due to the unusually high temperature in October, a steep temperature gradient developed between the city and nearby hilly regions. This resulted in winds from the hilly region areas moving towards Mumbai. These winds picked up dust from major construction projects in Navi Mumbai and surrounding areas.

(3) Refineries, industries and garbage-burning- These anthropological factors have further contributed to increase in the pollution levels.

Apart from this, the following factors common to major Indian cities lead to air pollution:

1) Urban development strategy in India — The current strategy focuses on real estate development, a widening of roads and allowing large fuel guzzling vehicles which are major reasons for increased pollution.

2) Expansion of ‘Grey’ infrastructure — Water bodies, urban forests, green cover, and urban agriculture have all reported shrinkage, and “grey” infrastructure has seen rapid expansion.

3) Land use change — The handing over of open spaces to real estate developers and lack of any meaningful afforestation affects the city’s ecology.

4) Promotion of car sales — Widening roads induces people to buy more cars, thus leading to more pollution levels.

5) Construction activities — It contributes roughly 10% of air pollution in Delhi-NCR. There are hardly any steps being taken to monitor construction activities.

What are the harmful effects of air pollution?

The harmful effects of air pollution have been tabulated below-

What Govt initiatives have been taken to reduce air pollution in Delhi?

(1) Crop Residue Management Scheme- Crop Residue Management (CRM) scheme which provides subsidy to farmers for buying ‘Turbo Happy Seeder‘, ‘Super SMS attachment’, ‘rotavators‘ and ‘superseeder’.

(2) Commission for Air Quality Management (CAQM)- CAQM is a statutory body formed under the Commission for Air Quality Management in National Capital Region and Adjoining Areas, Act 2021. CAQM has provided a framework to tackle the problem of air pollution due to stubble burning.

(3) Initiatives to reduce Vehicular Pollution- The shift from BS-IV to BS-VI, push for Electric Vehicles (EVs), Odd-even Policy have all been implemented to reduce Vehicular pollution.

(4) Graded Response Action Plan (GRAP)-  GRAP measures like shutting down thermal power plants and a ban on construction activities are implemented to curb air pollution.

What should be the way ahead to curb air pollution in Delhi and Mumbai?

A start has been made to recognise the severity of air pollution on the health of the population and the economy. Delhi and Mumbai are the two financial backbones of our country. The following measures need to be undertaken to curb air pollution in Delhi and Mumbai-

(1) Increase the AQI monitoring stations- The adequate numbers of AQI monitoring stations as mandated by the National Clean Air Programme (NCAP) must be installed. Also, sensor based AQI monitoring units that give hyperlocal data must be set up.

(2) Enhanced powers to the authorities to take action according to the hyperlocal data- It will help the authorities take pre-emptive actions and allow denser monitoring. For example, if it is found that construction is taking place in a certain pocket without following norms, the authorities can identify the location and immediately penalise the violators. 

(3) National Nodal Authority for Air pollution- India needs a nodal authority with constitutional powers to ensure collaborative pre-emptive action on air pollution with timelines for all stakeholders.

(4) Setting up Independent commissions for management of AQI- Independent commissions like the Commission for Air Quality Management (CAQM) for NCR and adjoining regions, should be set up in other major cities like Mumbai and Chennai. It will help in taking actions against the violators irrespective of the geographical region. Regional or airshed approach must be used to counter the geographical challenge to air pollution management as done in Los Angeles, Mexico City and many mega-urban regions in China.

(5) Stricter guidelines for industrial emmissions- SEBI’s Business Responsibility and Sustainability Report (BRSR) framework can lay down tighter guidelines to ensure uniformity in the unit of reporting pollutant emissions, declaration of air pollution mitigation targets (like companies do for carbon emissions), and reporting of disaggregated emissions data. We must reduce exposure across the value chain from production to consumption to recycling of goods and delivery of services.

(6) Making ‘Clean air’ an investment sector- The push for substitution of fossil fuels will increase investment opportunities in clean energy transition sector like green mobility, clean cooking. This will open up a new sector for investment and will help in reducing the air pollution simultaneously.

(7) Funds and Manpower Training to combat pollution- The Sixteenth Finance commission should provide finance to urban local bodies for climate change and air pollution reduction interventions. The urban local bodies manpower must be properly trained and the dysfunctional State pollution Control Boards must be empowered to take punitive actions. 

(8) Increased awareness and incentive for civil society- Different stakeholders need to know why cleaning the air will benefit their livelihoods and businesses. For instance, farmers will not curb stubble burning until a viable circular economy for alternative uses of biomass emerges. We must adopt sustainable lifestyles which are in line with government’s LiFE initiative.

(9) Increased use of Public transport and reduced dependence on private vehicles- The Delhi Master Plan target of 80 per cent of motorised trips by public transport by 2020 has not been met yet. The deadline has been shifted to 2041. This deadline needs to be met by augmenting the public transport system. The private vehicles use must be disincentivised by introducing ward-wise parking management area plans and parking tax.

(10) Limit crop residue burning- We must implement known solutions like shifting to less water-intensive crops, altering irrigation arrangements, timing, harvesting, baling practices and building a wider year-round market for straw.

(11) End-to-end construction and waste management– It is pivotal to reducing tonnes of dust and waste released in the air and water bodies.

(12) Learnings from London, China, Singapore, Hong Kong must be incorporated- London does not allow private vehicles in areas well-connected by public transport. China uses ‘fixed number of car sales per year‘ in Beijing. We must improve the public transport like London, China, Singapore and Hong-Kong.