India has once again ranked one with the Twenty-one of the world’s 30 cities having the worst air quality according to the compiled data of IQAir AirVisual’s 2019 World Air Quality Report, with six in the top ten. However, continuous improvements noticed in Chinese cities from the previous year.
Ghaziabad, capital New Delhi’s satellite city in the north of the state Uttar Pradesh, is ranked as the world’s most polluted city. In 2019, an average PM 2.5 concentration measurement was 110.2. It’s nine times more than the level which the US Environmental Protection Agency regards as healthy.
A public health emergency was declared in November after the air quality index (AQI) level exceeded 800, more than three times the “hazardous” level in certain parts of New Delhi.
An estimated 7 million premature deaths occur due to air pollution every year globally, according to the World Health Organization, and there is increased mortality from cardiovascular diseases, respiratory infections, and cancers.
More than 80% living in urban areas is exposed to air quality levels that exceed WHO guideline limits, and low and mid-income countries are most at risk.
“Air pollution constitutes the most pressing environmental health risk facing our global population,” the AirVisual report said.
According to AirVisual data, 27 of the 30 most polluted cities are in India, Pakistan, or Bangladesh of South Asia. Pakistan’s Gujranwala, Faisalabad, and Raiwind are among the ten, and the rank of major population centers of New Delhi, Lahore, and Dhaka is 5th, 12th, and 21st respectively.
Regionally, only six of 355 cities in South Asia, Southeast Asia, and the Middle East, all combined meet WHO annual targets and are worst affected, the report said.
However, some improvements have been noticed in South Asia compared to the last year. National air pollution in India decreased by 20% compared to 2018. The points highlighted by the report behind the decrease are economic slowdown, favorable weather conditions, and efforts towards cleaning the air. Ghaziabad had an average AQI 144.6 in 2017, 135.2 in 2018, and 110.2 this year.
The report also points the first National Clean Air Programme (NCAP) launched in India with the target of reducing PM 2.5 and the bigger particulate PM 10 air pollution by 20-30% in 102 cities by 2024 compared to 2017 levels.
Effect of Climate Crisis and Urbanization on Air Quality
There are “clear indications that climate change can directly increase the risk of exposure to air pollution” through events like desertification and increased frequency of forest fires and sandstorms.
The emission of greenhouse gas, a key driver of the climate crisis along with the burning of fossil fuel, is also a significant cause of dirty air.
Coal, on which many countries are still dependent because of their energy production, is the biggest contributor to PM 2.5 emissions. For example, China is the world’s largest producer and consumer of coal.
Rapid urbanization in industrializing Southeast Asian cities is also a major cause of air pollution that makes it hard to manage PM 2.5 levels, the report found.
For the first time, Indonesia’s Jakarta and Vietnam’s Hanoi overtook Beijing among the most polluted capital cities in the world, “in a historic shift reflecting the region’s rapid industrialization.” Now the annual PM 2.5 levels of these two capitals are 20% higher than those of Beijing, the report said.
“Fast growing cities need to make a choice if they want to grow in a sustainable manner,” said Yann Boquillod, director of air quality monitoring at IQAir.
However, it’s not all bad news. People power is bringing about change, he said.
“Up to recently, growth was more important than the environment, but we’re seeing a very clear trend that people are demanding more from their local governments,” Boquillod said.
“During the year 2019, citizens of Hanoi have massively become aware of the air quality in their city, thanks to the deployment of air monitors. This is an example how air quality data has helped to push government to improve the environment.”
Last year residents of Jakarta, which is Southeast Asia’s most polluted city and the fifth most polluted capital, have sued the government over worsening air pollution in the city. It will soon become the world’s biggest megacity by 2030, with a population of 35.6 million, according to a 2018 Euromonitor report.
“The city’s rapid growth has coincided with heightened PM 2.5 levels, as the growing population adds to its notorious traffic congestion, and coal-based energy demand,” the AirVisual report said.
A Few Positives
In Chinese cities, the average concentrations of pollutants reduced by 9% in recent years from 2018 to 2019, according to the report.
In Beijing, China’s capital, the annual PM 2.5 levels over the past decade has been reduced more than half and has dropped out of the world’s 200 most polluted cities by the efforts of controlling air pollution.
Still, 98% of Chinese cities exceeded WHO guidelines and 47 feature among the top 100 most polluted cities as per the 2019 World Air Quality Report.
The desert city of Hotan, in the Xinjiang region of western China, is the world’s second most polluted city in 2019, with an average AQI of 110.1 because of dust and sandstorms.
Another positive sign is that last year more countries expand their air quality monitoring, “with the number of monitoring stations increasing by more than 200% since the year prior.”
The communities will be aware of the quality of the air they are breathing with more monitoring data, and that will also help tackle air pollution globally, the report said.
The public air quality data is now continuously available for the first time for Angola, the Bahamas, Cambodia, DR Congo, Egypt, Ghana, Latvia, Nigeria, and Syria, the report found.
However, a significant gap still exists in air quality data for many parts of the world, the report said. It means the number of cities exceeding the WHO PM 2.5 threshold could be higher.
For example, there are not even 100 monitoring stations in Africa, a continent of 1.3 billion people that makes air quality data available to the public in real-time.
“Often locations bearing the highest particulate pollution levels tend to also notably have the least monitoring data,” said Frank Hammes, CEO of IQAir. “Leaving the most vulnerable communities without access to timely and relevant air quality data, necessary to guide actions to safeguard their health.”