Delhi's 'satisfactory' air was temporary, pollution crisis continues

Year after year, India cities are failing to breathe easily due to hazardous levels of pollutants

Delhi started the year breathing better. Between January 1 and March 15, average Air Quality Index (AQI) was 85, 'satisfactory' by pollution parameters. It was the first time in five years that Delhi had a 'satisfactory' AQI in March, according to the Commission for Air Quality Management. The statutory body considers AQI from 51 to 100 satisfactory.

 

Such respite from pollution is rare in Indian cities. The concentration of poisonous PM2.5 particulate matter averaged 50.6 micrograms per cubic metre (µg/m³) in the country last year, according to the ‘World Air Quality Report 2024’ by IQAir, a Swiss company. India is the fifth most polluted country in terms of concentration of PM2.5. In 2018-24, only Bangladesh and Pakistan had considerably higher PM levels than India. 

 

PM2.5 is small enough to go deep into the lungs, enter the bloodstream and it can cause severe respiratory diseases. New Delhi was the most polluted capital city in the world in 2024, having an average PM2.5 concentration of 91.8 μg/m³. Cities in the National Capital Region (NCR), of which Delhi is a part, are worryingly polluted. Delhi and Gurugram’s PM2.5 concentration rose from 102.1 μg/m³ and 84 μg/m³ in 2023 to 108.3 μg/m³ and 87.4 μg/m³ in 2024, respectively. Noida, Faridabad and Ghaziabad witnessed slight improvements in their PM2.5 numbers. India’s PM2.5 concentration in 2024 marginally improved from the year before. 

 

The World Health Organization’s air quality guideline in 2021 said that annual average concentrations of PM2.5 should not exceed 5 μg/m³, while 24-hour average exposures should not exceed 15 μg/m³ for more than three or four days per year.

 

Beijing, China’s capital, has cleaned up after earning notoriety for its extreme pollution. In 2020, Beijing suffered PM2.5 concentration of more than 50 μg/m³ for 24.4 per cent of the time. It reduced to 17.6 per cent in 2022 but increased to 20 per cent in 2024. Delhi had a PM2.5 concentration of more than 50 μg/m³ for 53.5 per cent of the time in 2020 and 56 per cent in 2023. In 2024, the concentration increased to 61.7 per cent. 

 

Recent improvements in NCR’s air quality must not cloud the severity of the problem. A recent paper by researchers at the Indian Institute of Technology Delhi said that climate change poses significant challenges to solar power generation and the future photovoltaic potential in the country. As India looks to switch to renewable energy sources, it becomes imperative to undertake climate and pollution mitigation efforts for a sustainable and resilient energy future.