Mumbai: IIT-B releases study on carbonaceous aerosol emissions

Mumbai: Amid the rising heatwave alerts in Mumbai, the Indian Institute of Technology (IIT) Bombay has released a study on the source apportionment and climate impacts of Carbonaceous Aerosol Emissions.

Carbonaceous aerosols are among the short-lived climate pollutants whose datasets are highly limited at global as well as national level hence narrowing our understanding of how they impact climate.

Under the aegis of the Ministry of Environment, Forest and Climate Change, the IIT-B spearheaded the COALESCE (Carbonaceous Aerosol Emissions) network project to investigate the origin, fate and climate impacts of carbonaceous aerosols on pan-India level. Started in 2017, the study involved over 20 institutions, 40 principal investigators and 125 researchers.

Far-ranging outcomes

Talking about the study's findings, IIT-B Prof Chandra Venkataraman said, “The far-ranging outcomes of the project include a new multi-pollutant emission inventory, a comprehensive data repository of ambient network measurements across India, emission factor measurements with detailed chemical speciation, and simulations of climate and air quality impacts with a suite of global and regional climate models.”

IIT-B Prof Harish Phuleria said, “The Speciated Multipollutant Generator (SMoG)-India emission inventory management system allows for online analysis and data download at multiple spatial scales from state, district to city levels.”

IIT Delhi Prof Gazala Habib said, “Particle and gaseous emission factors were measured with a newly developed and versatile source sampling system combined with activity surveys carried out in more than 100 districts of India, including the residential, agricultural, transport and brick production sectors. This (study) yielded perhaps the largest primary dataset of PM-2.5 chemical source profiles, emission factors and energy use estimates for a pan-India emission inventory.”

Elucidating the source apportionment efforts, Prof Ramya Sunder Raman, Indian Institutes of Science Education and Research (Bhopal), said, “The nationwide PM-2.5 speciation network yielded the most complete PM-2.5 speciation data for two full years across locations in India. It also resulted in important guidance documents; all the way from network design, particle sampling to instrumental chemical analyses, measurement of conventional bulk chemical species, organic molecular markers and carbon-isotopes.”

Compelling evidence

Illustrating the outcomes of climate impact simulations, IIT Delhi Prof Dilip Ganguly said, “We have found compelling evidence of the links between enhanced aerosol levels and worsening climate extremes, like heatwaves and rainfall suppression.”

IIT Delhi Prof Sagnik Dey pointed out, “New modeling results have thrown light on the aerosol lifecycle over India, including the ageing of black carbon, an important climate warming pollutant.”

Discussing future policy linkages of the project, Prof Venkataraman expressed hope that the data repositories, tools, and knowledge products emerging from the study would find wide application not only in India’s international commitments to the United Nations Framework Convention on Climate Change but also give an impetus to the National Clean Air Programme and disaster management activities.