Uttar Pradesh is the largest emitter of PM2.5 according to an analysis by the Council on Energy, Environment and Water ( CEEW).

Major Findings:

=> The high emissions from U.P. were largely due to a significant share of PM2.5 emissions from solid-fuel use in households and, by virtue of being India’s most populous state, had a higher proportion of households relying on this form of fuel.

=> Maharashtra, Gujarat, Odisha, West Bengal, Madhya Pradesh, Bihar, Tamil Nadu, and Rajasthan feature in the list of top polluters but are differently ranked by the five sources.

=> Jammu and Kashmir, Himachal Pradesh, Uttarakhand, and the Northeastern States of Arunachal Pradesh, Nagaland, Manipur, and Mizoram, were among the lowest emitters of PM2.5.

Common pollutants:

There are differences in the periods over which these sources track the emissions as well as the pollutants, but most track the important ones: PM2.5, PM10, Nox (nitrous oxides), SO2 (Sulphur dioxide), CO (Carbon Monoxide), NH3 (Ammonia), and NMVOC (Non-methane volatile organic compounds).

They also track the sources of pollutants ranging from agriculture waste burning, power utilities, industry, dust, transport and waste which account for nearly 95% of the sources of air pollution.

Significant variation:

The CEEW analysis found “significant variation” in the estimates by various sources going up to as much as 37% for particulate matter (PM2.5 and PM10), Nitrogen oxide (NOx), Sulphur dioxide (SO2) and Carbon Monoxide (CO).

The overall variation in residential PM2.5 emissions was less than 25%. However, SMoG’s residential PM2.5 emission estimates are approximately 50% higher than those estimated by TERI.

These differences had to do with the way each agency calculated emissions and the data sources they relied on.

Recommendations:

=> Government departments need to collaborate with each other for updating the emissions estimates periodically.

=> Because of the extent of variation, the Council said India ought to “develop and maintain a comprehensive inventory of baseline emissions” to evaluate if its policy and technological interventions were succeeding in reducing air pollution.

=> India has a National Clean Air Campaign (NCAP) that aims to reduce pollution in 122 of the most polluted cities by 2024.

• To meet the NCAP target of 20-30% reduction in particulate concentration by 2024, we need to estimate emission reductions needed across sectors.
• Estimating these reductions will only be possible when we have an official, representative emission inventory for India.