A new study shows that Delhi’s harmful air pollution is caused by a number of factors and not just increased traffic or population growth. Identifying the individual causes and placing them in their economic or cultural context will make it easier to draft and implement effective measures.
India’s most populous city is regularly being called the most polluted city in the world, with air pollution responsible for thousands of deaths each year. The problem is only expected to worsen in the coming years as Delhi’s population rises. The number of vehicles on the roads is expected to increase from 4.7 million in 2010 to nearly 26 million by 2030. Total energy consumption has already risen by 57 per cent from 2001 to 2011, according to the University of Surrey.
The grim statistics are putting scientists and policy makers alike under pressure to draft and implement effective measures. And key to those efforts are uncovering the underlying causes of the megacity’s poisonous air. Thanks to a team of researchers led by the University of Surrey, strides are being made in this direction.
Dismissing easy answers like the increased use of vehicles, industrial production or a growing population, Dr. Prashant Kumar of the University of Surrey says “the truth is that Delhi is a toxic pollutant punchbowl with myriad ingredients, all which need addressing in the round.”
His study identified a number of factors contributing to Delhi’s worsening air pollution. As a landlocked city, it has limited avenues to flush polluted air out of the city. Compounding this is that many of the regions surrounding the city are even more polluted than the city, itself including upwind industrial areas that use low-quality fuels such as raw wood, agricultural and plastic waste, cow dung and diesel generators.
Delhi’s architecture is also densely packed and the different building heights inhibit air circulation. These factors could help explain why fine particulate pollution rates are ten times higher in Delhi than coastal Chennai, which has ten times more cars.
While various measures can be designed to address each of these factors, Kumar also calls for a better understanding of the cultural context by those in charge of remedying Delhi’s air pollution problems: “Even the best science and technology will not succeed in reducing emissions and improving air quality if it is not considered in a broader framework of economic development of the country, rising awareness of public health risks and a change in attitudes and regulation towards poor quality fuels.”