Nagpur: So we thought Delhi is only to blame for contributing to the severe air pollution, India is battling with! We need to get our Math right as Nagpur is also one of the major contributors in emission. This was revealed in a research study of emissions and their sources in 20 cities including Nagpur. The researchers found that vehicle exhaust, suspended dust, construction activities, industrial exhaust, domestic cooking and heating are the primary sources of emissions in all cities.
Delhi turned out to be one of the most polluted cities in the world, the Air Quality Index (AQI), a metric to measure how polluted the air is, skyrocketed to 1000 in many areas of the city. These levels were at least thrice the deemed hazardous levels of 300. Air pollution has been linked to a host of issues, ranging from poor crop yield to innumerable health issues such as lung cancer, diabetes, cardiovascular diseases, asthma, bronchitis, dementia, and low birth weight, among others.
While this might seem a problem localized to Delhi, the rest of India doesn’t fare well either. Fourteen of the top fifteen polluted cities in the world are in India. So far, the primary focus of studies on air pollution in the country has been on Delhi, and to a lesser extent, on Mumbai and Kolkata. In fact, it is estimated that close to 99.5% of the 640 districts in India exceed the World Health Organization 2016 guidelines for particulate matter emissions of 10 μg/m. Now, a recent study has investigated the emission levels of multiple pollutants in twenty Indian cities, other than Delhi.
The study, undertaken by researchers from the Desert Research Institute, USA and Urban Emissions—a repository of research, information and analysis about of air pollution, has explored the ambient air quality of these cities and built a high-resolution ’emissions inventory’ of multiple pollutants.
The researchers chose 20 Indian cities, from 13 states, including Bengaluru and Chennai—two megacities with a population of over 10 million. The others include Nagpur, Chandigarh, Kanpur, Patna, Pune, Agra, Amritsar, Bhopal, Bhubaneswar, Coimbatore, Dehradun, Indore, Jaipur, Kochi, Ludhiana, Patna, Raipur, Ranchi and Varanasi. In all, these cities have 90 million inhabitants and cover an airshed of 44,000 sq. km.
The researchers collected four categories of data to build the emissions inventory. The first category involved data gathered from various ministries, professional organisations and policymakers. The second category consisted of dynamic data like vehicular speed maps for weekdays and weekends, power consumption and demand data, satellite feeds of open fires, dust events and weather forecasting models. In the third category, monitoring data from the websites of the Central Pollution Control Board and other organisations were considered. The fourth set of data came from Google, where it mapped commercial establishments like cafes, cinema theatres, hotels, hospitals and malls. Using this data, the researchers built the emissions inventory of various pollutants at a spatial resolution of 1 km x 1 km.
In tier-2 cities like Amritsar, Bhopal, Chandigarh, Coimbatore, Kanpur, Ludhiana, and Pune, small and medium-scale industries were found to be significant sources of emissions. They estimated the levels of hazardous pollutants like volatile compounds, black and organic carbon, sulphur dioxide, nitrogen oxides, carbon monoxide and dioxide and particulate matter.