'PM pollution increased by 20% in Himalayan region, Indo-Gangetic Plain and North-East'

New Delhi, May 25 -- A new study has found that particulate matter pollution across the Indo-Gangetic Plain (IGP), the Himalayan region and North-East India rose by more than 20 per cent in 2010-2019 compared with the 2000-2009 baseline, pointing to a growing air quality burden across some of India's most sensitive regions.

The study, Decadal shifts in aerosol hotspots and source attribution over IGP, north-east India and Himalayas: A 25-year (2000-2024) study, was published in the journal Atmospheric Environment and released on Monday.

Researchers found that carbonaceous aerosols in the eastern Indo-Gangetic Plain showed strong and rising trends between 2000 and 2024. These particles are largely produced by the burning of crop residue, wood and other organic material.

"The eastern Indo-Gangetic Plain, and increasingly North-East India, are carrying a disproportionate pollution burden and it is being driven almost entirely by biomass burning. That is the signal that stands out most clearly across 25 years of data," said Abhijit Chatterjee, co-author of the study and professor at the Bose Institute in Kolkata.

The study said the sharp increase in particulate matter levels in North-East India was linked to intensified slash-and-burn farming practices and widespread use of biomass as household fuel in rural areas during the study period. Researchers also found that pollution generated in the Indo-Gangetic Plain does not remain confined to the source regions but travels into the Himalayas.

According to the analysis, emissions from Punjab and Delhi affect the western Himalayan ranges, while pollution originating in Bihar and West Bengal reaches the eastern Himalayas.

"Our trajectory analysis shows that what is emitted in Punjab or Bihar does not stay there. It travels into the mountains. These are ecologically and climatically sensitive zones, and they are currently outside the scope of any structured clean air intervention in India," said Soumen Raul, senior research fellow at the Bose Institute.

The findings point to a widening regional air pollution challenge, with biomass burning emerging as a major contributor across multiple geographies over the 25-year study period.

Published by HT Digital Content Services with permission from Millennium Post.