Overview
- A peer‑reviewed study published on Monday, May 25, 2026, analysed 25 years of satellite data and found particulate matter rose more than 20 percent in the 2010s versus 2000s across the Indo‑Gangetic Plain, the Himalayan region, and North‑East India.
- Researchers identified carbonaceous aerosols from biomass burning — crop residue fires, slash‑and‑burn farming and household wood use — as the dominant and growing source, especially in the eastern IGP and North‑East where organic carbon and sulphate rose by about 50 percent in the 2010s.
- Backward trajectory modelling using MODIS and MERRA‑2 datasets showed pollution plumes from Punjab, Haryana, Bihar and West Bengal now travel into the western, central and eastern Himalayas, meaning the mountains are no longer insulated from lowland emissions.
- The study found limited reductions from India’s city‑focused National Clean Air Programme, noted a post‑NCAP rise of more than 30 percent in sulphates in Assam linked to power and refinery hubs, and called for expanded rural and ecosystem‑focused interventions.
- Higher aerosol loading in the Himalayas raises direct health risks for nearby communities and could speed glacier melt and alter river flows, posing wider threats to water security and regional climate stability.