Lack of official method a reason for India's air pollution data problem, says expert

India is one of the most polluted countries in the world, but still the country doesn't release how big the problem is. The reason: India doesn't have any standard official method for reporting air pollution, leading to missing data or huge data gaps. Globally, there are established official methods to address data gaps to construct a trend for compliance reporting. However, India has no such standard operating procedure in place to report air quality.

These findings are a part of the Centre for Science and Environment's report 'Breathing Space: How to Track and Report Air Pollution Under the National Clean Air Programme" released at the 2020 Anil Agarwal Dialogue and Annual Media Conclave held in Nimli, near Alwar.

The problem is not just missing data but inadequate data too. The report finds that 73 per cent of the air quality monitoring stations capture poor quality data on air quality trends. The norm is set at 104 days for manual monitors in a year but the available data from these stations is inadequate.

After a year of completion of the National Clean Air Programme (NCAP), a total of 122 cities were asked to reduce particulate pollution by 20-30 per cent by 2024 from 2017 levels -- they are expected to achieve an annual reduction of at least 6 per cent per year to meet the target.

"The cities are expected to immediately begin reporting on their annual progress. But for that, they must know the methods and standard operating procedures for such reporting. How will cities know if their pollution levels are rising or declining, asks Anumita Roychowdhury, Executive Director, Research and Advocacy, CSE.

Roychowdhury adds: "The report reviews global methods and demonstrates their application to Delhi's real-time data to assess the changes in air quality, and draws lessons for other cities."

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Currently, the Central Pollution Control Board (CPCB) releases annual average of stations and spatial average for cities based on analysis of only manual monitors. The real-time data is available on its portal, but it is not yet used for legal reporting.

The report says as the monitoring network expands for both manual and real-time monitors, cities need to know what kind of monitors should be used, how data should be averaged and what geography they should represent.

While air quality monitoring has begun to expand under the NCAP to address the data deficit, without a methodical system for reporting, the data will remain unusable and cannot drive change in cities.

"Given the limitation of missing data, India requires methods for addressing data gaps, as other governments do, to meet the legal requirement of air quality trend reporting and compliance. India has not adopted such methods yet," says Roychowdhury.

The report, after analyzing methodologies for compliance and trend analysis  across geographies such as US, Europe, Canada and Australia, found the US method was most applicable to address data gaps in India. It shows how such methods need to be adopted and how their application to Delhi's real-time data can show the change in air quality.

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