Data-led climate action essential for tackling air pollution in Asian cities

The WHO list of the world’s most polluted cities is almost a roll call of the largest cities in China and India

In some developed economies, there has been a movement away from cities amid the lockdowns of the past three years, but the reality is a far greater global migration into cities took place in recent decades.

The rise in pollution levels in these ever-growing cities presents a serious health and environmental challenge, but it is one that can be addressed with the right planning. This needs to be underpinned by a detailed understanding of local micro-environments and pressure points for emissions.

Urban areas are now home to 55% of the world’s population, a figure that is forecast to rise to 68% by 2050. At present, cities account for just 2% of the world’s land usage while creating 70% of the global waste and consuming almost 80% of the world’s energy. They account for more water, energy, and natural resources usage, and emit more heat and pollution than the countryside.

In Asia, the region’s two most populous countries illustrate why. In 2000, just 36% of China’s population lived in cities, while 50 years earlier it was only 13%. By 2020, it was 64%, having seen over 400 million moving into cities during a 20-year period. India, meanwhile, has seen the percentage of its population living in cities rise to 35% in 2021, up from 28% in 2000 and 17% in 1950

In China and India, the change in the urban-rural balance, alongside near unrestrained economic growth, has exacerbated already prevalent pollution. The dust storms from the Gobi Desert that affect Beijing, northeast China, Korea and Japan are more toxic as they collect factory and car fumes.

In Hong Kong, the narrow streets become highly polluted, while heavy shipping traffic, often with poor quality fuel, is also highly polluting. And in Indonesia, the fires from tree burning can create a pall of smog across the region. Geography and pollution create similar problems in India. In all these countries, coal use is the main source of energy.

Asian cities among the most polluted

The World Health Organisation (WHO) list of the world’s most polluted cities is almost a roll call of the largest cities in China and India. Five of the top ten are in India, while China accounts for a third of those in the top 100. South, Southeast, and Northeast Asia alone account for almost two-thirds of those cities in the top 100.

Local inhabitants are generally aware of the unhealthy air quality outdoors, but often feel helpless. Many leave when their circumstances allow. Conversely, it becomes very challenging to recruit staff from overseas to work in these cities, particularly if they have young children.

For city governments and planners, these issues should matter deeply. They are custodians of the city for future generations, so it’s incumbent on them to have a feasible long-term strategy in place to ensure the city is liveable and can thrive. 

A phenomenon of the 21st century is the emergence of megacities, populated by tens of millions. In the future, they will compete more aggressively for resources, talent, investment, jobs, and so forth. Quality of life and general liveability will be key selling points. Clean air, clean water and clean land have a big part to play.

So, for example, if Chengdu-Chongqing is considered less appealing, top talent will go to Beijing-Tianjin or Hong Kong-Shenzhen, or perhaps overseas to Tokyo-Yokohama.

Highly informed decision-making needed

It means that city planners need to make highly informed long-term decisions. They will need to understand local micro-environments, air quality, and pressure points for emissions, such as a busy road junction, a construction site, or perhaps a certain time of the day.

The margin of error is small, since the consequences can be profound – a city that is too difficult or unpleasant to live in will hollow out as people leave. City governments need highly localised data to enable effective pollution-cutting strategies to be put in place. Traffic management, water usage, utility needs, waste management, and more all play a part in a holistic city management strategy.

At present, 99% of the world’s population breathes air that exceeds WHO guidelines. Outdoor and indoor air pollution are responsible for 4.2 million and 3.2 million deaths a year. The need for data-led action against air pollution is clear, while the backdrop is a do-or-die one for city governments.